Introduction
East African fruticose and foliose lichens were studied in detail through the joint efforts of Dougal Swinscow and Hildur Krog in the 1970s and 1980s, resulting in a synthesis in 1988 (Swinscow & Krog Reference Swinscow and Krog1988). The taxonomy and nomenclature of taxa treated in their identification book ‘Macrolichens of East Africa’ have been significantly changed as a result of molecular genetic studies carried out during the last decades in several taxonomic groups, especially in the family Parmeliaceae (e.g. Blanco et al. Reference Blanco, Crespo, Elix, Hawksworth and Lumbsch2004, Reference Blanco, Crespo, Ree and Lumbsch2006; Crespo et al. Reference Crespo, Lumbsch, Mattsson, Blanco, Divakar, Articus, Wiklund, Bawingan and Wedin2007, Reference Crespo, Kauff, Divakar, del Prado, Pérez-Ortega, de Paz G, Ferencova, Blanco, Roca-Valiente and Núñez-Zapata2010, Reference Crespo, Divakar and Hawksworth2011; Divakar et al. Reference Divakar, Lumbsch, Ferencova, Del Prado and Crespo2010; Thell et al. Reference Thell, Crespo, Divakar, Kärnefelt, Leavitt, Lumbsch and Seaward2012; Leavitt et al. Reference Leavitt, Kirika, Amo de Paz, Huang, Hur, Elix, Grewe, Divakar and Lumbsch2018; Grewe et al. Reference Grewe, Ametrano, Widhelm, Leavitt, Distefano, Polyiam, Pizarro, Wedin, Crespo and Divakar2020). This species-rich lichen family is widely distributed in the Southern Hemisphere and its largest clade, the parmelioid clade, contains one tenth of the lichen species known worldwide (with c. 1800 spp. (Kirk et al. Reference Kirk, Cannon, Minter and Stalpers2008; Thell et al. Reference Thell, Crespo, Divakar, Kärnefelt, Leavitt, Lumbsch and Seaward2012)). The group is also rich in lichen secondary metabolites with various bioactive and other potential roles. However, the identification of these taxa is difficult since the only key to macrolichens of East Africa (Swinscow & Krog Reference Swinscow and Krog1988) needs to be revised. In an attempt to update a considerable part of the key, we are concentrating on parmelioid taxa in Kenya. This family is not only rich in species, but also characterized by an enormous diversity in its lichen secondary metabolites (LSMs) (Divakar & Upreti Reference Divakar and Upreti2005). Additionally, our knowledge of the various biological and other roles of these unique substances has also increased (Molnár & Farkas Reference Molnár and Farkas2010; Nguyen et al. Reference Nguyen, Chollet-Krugler, Gouault and Tomasi2013; Petrova et al. Reference Petrova, Kello, Kuruc, Backorova, Petrovova, Vilkova, Goga, Rucova, Backor and Mojzis2021). However, little information is available regarding the application of LSMs in terms of their potential insecticidal and antiprotozoal activity (Muhoro & Farkas Reference Muhoro and Farkas2021). Since Parmeliaceae is largely found in the Southern Hemisphere with main distribution centres being in southern Africa, South America and Australia (Elix Reference Elix1993), field collectors in these regions frequently meet representatives of this taxonomic group. In the case of Kenya, 178 of the c. 900 lichen species belong to the parmelioid clade (Krog & Swinscow Reference Krog and Swinscow1987; Swinscow & Krog Reference Swinscow and Krog1988; Hale Reference Hale1990; Staiger & Kalb Reference Staiger and Kalb1995; Alstrup & Aptroot Reference Alstrup and Aptroot2005; Alstrup & Christensen Reference Alstrup and Christensen2006; Archer et al. Reference Archer, Elix, Fischer, Killmann and Sérusiaux2009; Alstrup et al. Reference Alstrup, Aptroot, Divakar, LaGreca and Tibell2010; Kirika et al. Reference Kirika, Mugambi, Lücking and Lumbsch2012, Reference Kirika, Divakar, Crespo, Gatheri, Mugambi, Leavitt, Moncada and Lumbsch2016a, Reference Kirika, Divakar, Crespo, Gatheri, Mugambi, Leavitt, Moncada and Lumbschb, Reference Kirika, Divakar, Crespo, Gatheri, Mugambi, Leavitt, Moncada and Lumbschc, Reference Kirika, Divakar, Crespo, Mugambi, Orock, Leavitt, Gatheri and Lumbsch2017a, Reference Kirika, Divakar, Crespo, Mugambi, Orock, Leavitt, Gatheri and Lumbschb, Reference Kirika, Divakar, Crespo and Lumbsch2019; Lücking & Timdal Reference Lücking and Timdal2016; Bjelland et al. Reference Bjelland, Bendiksby and Frisch2017; Kantelinen et al. Reference Kantelinen, Hyvärinen, Kirika and Myllys2021; Kirika & Lumbsch Reference Kirika and Lumbsch2021) .
Certain species of the parmelioid clade were investigated in our study to determine their potential insecticide role, the second author using his parasitological experience to carry out field and experimental studies on malaria vector mosquitoes. To aid further field collections of relatively frequent lichens, one of the main aims of this study was to prepare a practical key for identifying species of the parmelioid clade found in Kenya.
Materials and Methods
The list of parmelioid taxa in Kenya (see Supplementary Material, available online) was extracted from the species treated by Swinscow & Krog (Reference Swinscow and Krog1988). Additional species were added from recently published literature sources (Kirika et al. Reference Kirika, Divakar, Crespo, Gatheri, Mugambi, Leavitt, Moncada and Lumbsch2016a, Reference Kirika, Divakar, Crespo, Mugambi, Orock, Leavitt, Gatheri and Lumbschb, Reference Kirika, Divakar, Crespo, Leavitt, Mugambi, Gatheri and Lumbschc, Reference Kirika, Divakar, Buaruang, Leavitt, Crespo, Gatheri, Mugambi, Benatti and Lumbsch2017a, Reference Kirika, Divakar, Leavitt, Buaruang, Crespo, Mugambi, Gatheri and Lumbschb, Reference Kirika, Divakar, Crespo and Lumbsch2019). Altogether 178 species were listed belonging to the genera Bulborrhizina (1), Bulbothrix (9), Canoparmelia (9), Cetrelia (1), Crespoa (1), Flavoparmelia (4), Flavopunctelia (2), Hypotrachyna (37), Melanelixia (1), Myelochroa (1), Parmelia (2), Parmelinella (1), Parmotrema (64), Pseudoparmelia (2), Punctelia (9), Relicina (4), Remototrachyna (1) and Xanthoparmelia (29). In compiling the key to parmelioid lichen species of Kenya, the most important sources were the identification keys prepared by Swinscow & Krog (Reference Swinscow and Krog1988), Divakar & Upreti (Reference Divakar and Upreti2005) and Awasthi (Reference Awasthi2007). Several valuable works on various genera were also studied from the Neotropics (Adler Reference Adler1992, Reference Adler2014; Sipman et al. Reference Sipman, Elix and Nash2009; Canêz & Marcelli Reference Canêz and Marcelli2010; Benatti Reference Benatti2012a, Reference Benattib, Reference Benatti2013, Reference Benatti2014; Kukwa et al. Reference Kukwa, Bach, Sipman and Flakus2012; Divakar et al. Reference Divakar, Crespo, Núñez-Zapata, Flakus, Sipman, Elix and Lumbsch2013; Spielmann & Marcelli Reference Spielmann and Marcelli2020), and Smith et al. (Reference Smith, Aptroot, Coppins, Fletcher, Gilbert, James and Wolseley2009) was consulted for morphological details. Some of the important morphological characters are illustrated: lamina, lobe margin, lower and upper surface (Fig. 1A); cilia (Figs 1B & 2A); rhizines (Figs 1B, 2B & 3); isidia (Fig. 4); pseudocyphellae (Fig. 5A); soredia (Figs 5B & 6).
Fig. 1. Parts of a foliose thallus indicated by arrows. A, upper and lower surface, lamina, lobe margin (Flavoparmelia caperata, A. M. Muhoro 21/01). B, appendages on the thallus: cilia, rhizines (Parmotrema ultralucens, VBI 2217). Scales: A = 1 mm; B = 0.5 mm. In colour online.
Fig. 2. Appendages on the thallus. A, bulbate cilia indicated by arrows (Bulbothrix isidiza, VBI 1691). B, branched rhizine (Parmotrema ultralucens, VBI 2217). Scales: A & B = 0.5 mm. In colour online.
Fig. 3. Lower surface of the thallus (Flavoparmelia caperata, A. M. Muhoro 21/01). A, paler zone at the margin with pale rhizines. B, inner dark rhizines. Scales: A & B = 0.5 mm. In colour online.
Fig. 4. Laminal isidia. A, semiglobular to cylindrical isidia often with brown tips, mostly simple (Bulbothrix isidiza, VBI 1691). B, cylindrical and claviform isidia (Hypotrachyna vexans, VBI 1741). C, cylindrical granular isidia with brown tips (Parmelinella schimperiana, VBI 2309). D, subglobose to cylindrical or inflated isidia, simple or branched (Parmotrema tinctorum, VBI 4917). Scales: A‒D = 0.2 mm. In colour online.
Fig. 5. Morphological details (Flavopunctelia flaventior, VBI 2321). A, laminal pseudocyphellae. B, marginal linear soralia. Scales: A & B = 0.5 mm. In colour online.
Fig. 6. Laminal punctiform soralia. A, Canoparmelia texana (VBI 2308). B, Parmotrema sp. (A. M. Muhoro 20/01). Scales: A = 0.5 mm; B = 1 mm. In colour online.
The dichotomous main key leads to species where the genus has only a small number of representatives (maximum 4 species), but otherwise to genera. Larger genera are treated separately after the main key. Bulborrhizina (1) is treated in the generic key (Bulbothrix s. lat.) together with Bulbothrix (9); Canoparmelia (9) and Pseudoparmelia (2) are also treated in the same key.
The key was tested using East African (mostly Tanzanian) herbarium specimens deposited in VBI (abbreviation according to Thiers (Reference Thiers2022)) and recently collected samples. Fragments of parmelioid thalli were collected by the second author in Kenya in 2020 and 2021; localities are listed below. Morphology and anatomy were studied using a Nikon Eclipse/NiU compound microscope and a Nikon SMZ18 stereomicroscope. Micrographs were prepared using a Nikon Fi3 camera with NIS-Elements BR ML software. HPTLC analysis was carried out according to standard methods for analyzing lichen samples described by Arup et al. (Reference Arup, Ekman, Lindblom and Mattsson1993) and Molnár & Farkas (Reference Molnár and Farkas2011).
Specimen details
Localities visited
Kenya: Uasin Gishu County: Eldoret in Sukunanga estate opposite Toyota Kenya c. 1.5 km from Sosiani River along Nakuru road, 0°29ʹ32ʺN, 35°18ʹ06ʺE, alt. 2129 m, from bark of trees, 2020, A. M. Muhoro 20/01. Nyeri County: at the foot of Mt Kenya, c. 1 km from Naro Moru entry gate to Kenya Wildlife Service in Gitinga Village, 0°10ʹ25.84ʺS, 37°9ʹ3.40ʺE, alt. 2454 m, from bark, twigs and branches of trees in tropical rainforest, 2021, A. M. Muhoro 21/01, 21/02.
Specimens used for micrographs
Bulbothrix isidiza (Nyl.) Hale. Tanzania: Morogoro Region: Northern Uluguru Mts, near the town of Morogoro, valley leading S from Bigwa Mission to Lupanga peak, on E-facing slope, alt. 1100–1200 m, from bark of Dahlbergia lactea in dry rocky woodland, 1988, T. Pócs 88191/P (VBI 1691).
Canoparmelia texana (Tuck.) Elix & Hale (as Pseudoparmelia texana (Tuck.) Hale). Tanzania: Arusha Region: Ngorongoro Conservation Area, NE rim of Ngorongoro Crater, inner slope, NW of Oljoro Nyuki, alt. 2220 m, ramicolous in mature, mist affected, heavily grazed Acacia lahai stand, very rich in epiphytes, 1989, T. Pócs, A. Kijazi, P. Murphy 89011/PB, det. H. Krog, rev. E. Farkas (VBI 2308).
Flavopunctelia flaventior (Stirt.) Hale (as Punctelia flaventior (Stirt.) Krog). Tanzania: Arusha Region: Ngorongoro Conservation Area, NE rim of Ngorongoro Crater, inner slope, NW of Oljoro Nyuki, alt. 2220 m, ramicolous in mature, mist affected, heavily grazed Acadia lahai stand, very rich in epiphytes, 1989, T. Pócs, A. Kijazi, P. Murphy 89011/X, det. H. Krog, rev. E. Farkas (VBI 2321).
Hypotrachyna vexans (Zahlbr. ex W. L. Culb. & C. F. Culb.) Divakar et al. (as Cetrariastrum vexans (Zahlbr.) W. L. Culb. & C. F. Culb.). Tanzania: Mbeya Region: Southern Highlands, Poroto Mts, W of Isongole Village, SE of Ngozi Crater, alt. 2000 m, from bark of Hagenia sp. in montane rainforest, 1989, T. Pócs, E. Farkas, H. Krog 89128/H, det. H. Krog, rev. E. Farkas (VBI 1741).
Parmelinella schimperiana Kirika & Divakar (as Pseudoparmelia wallichiana (Taylor) Krog & Swinscow). Tanzania: Arusha Region: Mt Meru, W slope, on the ridge above Laikinoi, alt. 2600 m, corticolous in Juniperus-Podocarpus usambarensis forest, 1988, T. Pócs & Helsinki Univ. Bot. Dept. 88296/L, det. H. Krog, rev. E. Farkas (VBI 2309).
Parmotrema tinctorum (Nyl.) Hale. Tanzania: Tanga Region: Lushoto District, West Usambara Mts, W slopes of Gonja Hill, 5 km E of Mgwashi Village, alt. 1600–1700 m, from bark in montane evergreen forest, 1988, T. Pócs, H. Krog 88205/LC, det. H. Krog (VBI 1741).
Parmotrema ultralucens (Krog) Hale. Tanzania: Tanga Region: Lushoto District, East Usambara Mts, Hunga stream valley, below Derema Village, alt. 840 m, rupicolous on granitic river-bed rocks, 1987, K. Pócs 87037/U, det. H. Krog (VBI 2217).
Key to species of the parmelioid clade in Kenya
Parmelioid species share the following characters within Parmeliaceae: photobiont green alga; foliose growth form, not umbilicate, thallus corticate above and below, adnate or loosely attached to substratum; presence of rhizines; medulla solid, grey, yellowish green or brownish; if present, fruiting body apothecium with thalline exciple; simple ascospores; laminal pycnidia.
Further keys lead to species of the genera Bulborrhizina (1) and Bulbothrix (9), Canoparmelia (9) and Pseudoparmelia (2), Hypotrachyna (37), Parmotrema (64), Punctelia (9) and Xanthoparmelia (29) and follow the main key.
1 Pseudocyphellae present, may occur on both sides ……… 2
Pseudocyphellae absent, cortex continuous on both sides ……… 8
2(1) Pseudocyphellae may occur on both upper and lower surfaces in the genus but this species has pseudocyphellae on upper surface only, together with granular and coralloid isidia on large wide lobes, lower side is black with black rhizines; cortex K+ yellow, atranorin; medulla K−, C−, KC+ pink, Pd−, alectoronic acid, α-collatolic acid ……… ……… Cetrelia braunsiana (Müll. Arg.) W. L. Culb. & C. F. Culb.
Pseudocyphellae present on upper surface, thallus otherwise ……… 3
3(2) Thallus grey; cortex K+ yellow, atranorin ……… 4
Thallus yellow-green or brown; cortex K−, with or without usnic acid ……… 6
4(3) Pseudocyphellae mostly linear effigurate, reticulate, seldom punctiform, lobes sublinear; medulla K+ red, Pd+ orange, salazinic acid ……… 5
Pseudocyphellae punctiform to suborbicular, lobes rotund ……… Punctelia (9 species)
5(4) Pseudocyphellae linear effigurate, cylindrical isidia present with brown tips; lobes 1–3 mm wide, underside black; rhizines simple to bifurcate; lignicolous at c. 3000 m alt. ……… Parmelia saxatilis (L.) Ach.
Pseudocyphellae linear, reticulate, often developing into soredia; lobes 2–5 mm wide, underside black; rhizines simple to squarrose; saxicolous at 3500–4200 m alt. ……… Parmelia sulcata Taylor
6(3) Thallus olive to reddish brown; isidia present, cylindrical and punctiform soredia originate from pseudocyphellae, lower side brown to black with scattered simple rhizines; cortex without usnic acid, HNO3−; medulla C+ red, lecanoric acid ……… ……… Melanelixia subaurifera (Nyl.) O. Blanco et al.
Thallus yellow-green, pseudocyphellae punctiform to elongate; cortex with usnic acid; medulla C+ red, lecanoric acid 7
7(6) Soredia present, soralia marginal linear or laminal punctiform; underside black, with a brown and glossy, broad, naked marginal zone; rhizines few, scattered, usually black but towards the margin pale brown or with white tips; apothecia common, with sorediate thalline exciple; ascospores long ellipsoid, 15–18 × 6–8 μm. ……… Flavopunctelia flaventior (Stirt.) Hale
Soredia and isidia absent; underside black, glossy brown or white mottled in a broad marginal zone; rhizines short, inconspicuous; apothecia often numerous towards the centre of the thallus, with a pseudocyphellate thalline exciple; ascospores ellipsoid, 12–15 × 8–10 μm ……… Flavopunctelia praesignis (Nyl.) Hale
8(1) Thallus yellow, yellow-green or brown ……… 9
Thallus grey ……… 18
9(8) Thallus brown, grey-brown; upper cortex HNO3+ blue-green, without usnic acid ……… Xanthoparmelia pr. p.
Thallus yellow, yellow-green, pale yellowish grey; upper cortex HNO3−, with usnic acid ……… 10
10(9) Bulbate cilia present at lobe margin, lobes pale yellow ……… 11
Lobe margin without cilia, yellow-green to green (pale yellow in Relicina abstrusa) ……… 14
11(10) Isidia absent ……… 12
Cylindrical isidia present ……… 13
12(11) Thallus yellow-green to green, with 1–2 mm wide sublinear, dichotomous lobes; underside black; cortex with usnic acid; medulla K+ yellow, C+ pale yellow to orange (unknown substance) and Pd+ deep orange (unknown substance, ‘echinocarpic acid’); apothecia laminal, thalline exciple pilose; ascospores subglobose, 6–8 × 3–5 μm……… ……… Relicina echinocarpa (Kurok.) Hale
Lobes 3–6 mm wide, yellow-green to green, medulla pale yellow; apothecia laminal, thalline exciple crenate; ascospores subglobose, 8–10 × 7–8 μm; undetermined pigment and substances, ±atranorin (trace); corticolous at 1500–2200 m alt. ……… ……… Relicina limbata (Laurer) Hale
13(11) Lobes 1–2 mm wide, pale yellow, marginal cilia well developed, clearly bulbate; medulla white; apothecia absent in East African specimens; cortex, usnic acid; medulla K+ red, Pd+ orange, norstictic acid; corticolous in mangroves at 0–300 m alt. ……… ……… Relicina abstrusa (Vain.) Hale
Lobes 0.8–1.5 mm wide, bright yellow to yellow-green, ±eciliate; rhizines sometimes protruding beyond the lobe margins; medulla pigmented faintly yellow, especially near the upper cortex; apothecia common, up to 2 mm diam., thalline margin entire or crenate, disc flat; ascospores 8–10 × 4–6 μm; cortex, usnic acid; medulla Pd+ orange-red, protocetraric acid, ±fatty acid; corticolous on twigs and branches in mangroves, 0–500 m alt. ……… Relicina malaccensis (Nyl.) Kirika et al.
14(10) Lobes rounded ……… 15
Lobes elongated ……… Xanthoparmelia pr. p.
15(14) Laminal soralia present ……… 16
Laminal soralia absent, dactyls present or absent ……… 17
16(15) Lobes 5–10 mm wide, imbricate in central parts, soralia starting from individual pustules but soon coalescing to cover larger areas; underside black with a fairly wide brown, naked marginal zone; rhizines simple, slender, dense or scattered, black, often tipped with white or brown; apothecia not seen in East African material; pycnoconidia weakly bifusiform, 5–6 μm long; cortex, usnic acid, ±atranorin (trace); medulla Pd+ orange-red, protocetraric acid, caperatic acid; corticolous at 1500–3600 m alt. ……… Flavoparmelia caperata (L.) Hale
Lobes 1–5 mm wide, soralia punctiform, becoming confluent over larger areas; underside black, with a narrow, brown marginal zone; rhizines simple, black to brown, some tipped with white; apothecia and pycnidia not seen in material from Kenya; cortex, usnic acid; medulla K+ red, Pd+ orange, salazinic acid; corticolous, lignicolous, or saxicolous at 1100–2700 m alt. ……… Flavoparmelia soredians (Nyl.) Hale
17(15) Lobes 1–2.5 mm wide, dactyls laminal, crowded in central parts of the thallus, mainly closed but occasionally becoming eroded or with a small perforation at the apex; underside velvety black to the margins; rhizines short, black; apothecia rare, up to 2 mm diam., with a thick, crenate thalline margin; spores 10–16 × 5–8 μm; pycnoconidia filiform, 10–12 μm long; cortex, usnic acid; medulla Pd+ orange-red, protocetraric acid; saxicolous at 1750 m alt. ……… ……… Flavoparmelia pachydactyla (Hale) Hale
Lobes 5–8 mm wide, without dactyls; underside black, with a narrow, brown, naked marginal zone; rhizines simple, black or tipped with white; apothecia not seen in East African material; pycnoconidia weakly bifusiform, 7–8 μm long; cortex, usnic acid, ±atranorin (trace); medulla Pd+ orange-red, protocetraric acid, caperatic acid; saxicolous at 3600 m alt. ……… ……… Flavoparmelia rutidota (Hook. f. & Taylor) Hale
18(8) Upper surface mostly maculate ……… 19
Upper surface mostly emaculate ……… 20
19(18) Lobes large, rotund, wider than 0.5 cm, upper cortex often reticulately cracked; maculae may occur… ……… ……… Parmotrema pr. p. (65 species)
Lobes narrower than 0.5 cm, rotund, subrotund or sublinear; emaculate species may occur ……… ………Canoparmelia (9 species) and Pseudoparmelia (2 species)
20(18) Bulbate cilia present at lobe margin………Bulborrhizina (1 species) and Bulbothrix (9)
Lobe margin without bulbate cilia ……… 21
21(20) Lobes large, rotund, wider than 0.5 cm ……… Parmotrema pr. p. (65 species)
Lobes narrower, rotund or elongated, narrower than 0.5 cm ……… 22
22(21) Thallus with secalonic acid A yellow pigment ……… 23
Thallus without secalonic acid A yellow pigment ……… Hypotrachyna (37 species)
23(22) Medulla yellow to salmon pink, pigment K−; lobes sublinear to irregular, 3–5 mm wide, pale grey; rhizines mainly simple but a few branched, some growing out horizontally from the margins; pustular soralia and open dactyls laminally and submarginally situated; cortex K+ yellow, atranorin; medulla, triterpenoids, secalonic acid A ……… ……… Myelochroa aurulenta (Tuck.) Elix & Hale
Medulla white; lobes irregularly to subirregularly branched, 3–8 mm wide, margins ciliate; upper surface grey, grey-green, usually pruinose; isidia cylindrical, mostly simple, also branched; lower surface black with brown papillate margins; rhizines black, simple, evenly distributed; apothecia 1–5 mm; ascospores 5–10 × 5–7.5 μm; pycnidia not seen in material from Kenya; cortex K+ yellow, UV−, secalonic acid A and atranorin; medulla K+ yellow turning red, C−, KC−, Pd+ orange-red, UV−, salazinic acid ……… Parmelinella schimperiana Kirika & Divakar
Key to species of Bulborrhizina Kurok. (1) and Bulbothrix Hale (9)
Bulborrhizina: thallus pale straw-yellow, loosely adnate, divaricate, composed of linear lobes divided dichotomously, canaliculate below. Cortex with atranorin.
Bulbothrix: thallus grey, relatively small. Surface without pseudocyphellae, marginal cilia bulbate. Cortex with atranorin. Apothecia, isidia or phyllidia may occur.
1 Apothecia present or absent; soredia, isidia and phyllidia absent ………2
Apothecia rare; isidia or phyllidia present ………5
2(1) Underside pale ………3
Underside black ………4
3(2) Apothecia present; underside pale brown ……… Bulbothrix hypocraea (Vain.) Hale
Apothecia absent; underside pale straw-yellow; medulla, salazinic acid (major), gyrophoric acid (minor) ……… ……… Bulborrhizina africana Kurok.
4(2) Ascospores 8–12 × 6–8 μm ……… Bulbothrix sensibilis (Steiner & Zahlbr.) Hale
Ascospores 16–20 × 8–12 μm ……… Bulbothrix meizospora (Nyl.) Hale
5(1) Underside pale brown ………6
Underside dark brown to black ………7
6(5) Upper surface faintly to distinctly maculate, cilia bulbate ……… Bulbothrix isidiza (Nyl.) Hale
Upper surface emaculate, cilia reduced to bulbate nodules ……… Bulbothrix kenyana Kirika et al.
7(5) Phyllidia numerous, cylindrical isidia absent ……… Bulbothrix suffixa (Stirt.) Hale
Phyllidia rare or absent, cylindrical isidia present ………8
8(7) Rhizines branched; medulla C+ rose, Pd−, gyrophoric acid ……… Bulbothrix goebelii (Zenker) Hale
Rhizines simple; medulla C−, Pd+ orange ………9
9(8) Apothecia ecoronate; K+ yellow turning red, salazinic acid present ……… ………Bulbothrix sublaevigatoides (C. W. Dodge) Kirika et al.
Apothecia (rare) coronate; K+ red, norstictic acid present ……… Bulbothrix ventricosa (Hale & Kurok.) Hale
Key to species of Canoparmelia Elix & Hale (9) and Pseudoparmelia Lynge (2)
Canoparmelia: lobes usually narrower than 5 mm, rotund or subrotund. Marginal cilia absent. Medulla white. Apothecia, soralia, isidia or dactyls may occur. Rhizines usually simple, often with white, frayed tips. Cortex usually emaculate, with atranorin and/or usnic acid. Corticolous.
Pseudoparmelia: lobes usually narrower than 5 mm, sublinear or irregularly incised. Marginal cilia absent. Medulla white or pigmented. Apothecia and isidia occur. Rhizines usually simple. Cortex shiny, emaculate, with atranorin. Saxicolous.
1 Thallus pale yellow to yellow-green ……… Canoparmelia ecaperata (Müll. Arg.) Elix & Hale
Thallus pale grey to ash grey ………2
2(1) Thallus saxicolous ………3
Thallus corticolous ………4
3(2) Medulla white, with salazinic acid (Pd+ orange-red, K+ red); lobes sublinear, 4–8(– 10) mm wide; isidia laminal, semiglobular or cylindrical, simple; underside black with a brown apical zone; apothecia laminal, thalline margin isidiate ……… ……… Pseudoparmelia usambarensis (J. Steiner & Zahlbr.) Krog & Swinscow
Medulla faintly pink, with perlatolic acid aggr., echinocarpic acid (Pd+ deep orange, K+ yellow, C+ yellow, KC+ salmon); lobes irregularly incised, 2–2.5–(3) mm wide, imbricate; isidia short, fairly coarse, cylindrical to claviform, simple or sparingly branched; underside black with a dark brown, naked marginal zone; apothecia rare, with crenate thalline margin ……… ……… Pseudoparmelia singularis Krog & Swinscow
4(2) Soredia, isidia or dactyls present ………5
Soredia, isidia or dactyls absent ………9
5(4) Laminal, punctiform soralia present ……… Canoparmelia texana (Tuck.) Elix & Hale
Isidia or dactyls present ………6
6(5) Laminal dactyls with open tips present ……… Canoparmelia pustulescens (Kurok.) Elix
Cylindrical isidia present ………7
7(6) Upperside matt, emaculate, Pd+ orange-red (protocetraric acid) ……… ……… Canoparmelia amazonica (Nyl.) Elix & Hale
Upperside maculate, cracked and rugose, Pd−, containing perlatolic acid or divaricatic acid ………8
8(7) Medulla with perlatolic acid ……… Canoparmelia caroliniana (Nyl.) Elix & Hale
Medulla with divaricatic acid ……… Canoparmelia concrescens (Vain.) Elix & Hale
9(4) Lobes 1–3 mm wide………Canoparmelia rodriguesiana (Hue) Elix
Lobes 3–8 mm wide ………10
10(9) Upperside maculate; medulla with divaricatic acid and an unknown substance (C+ pale pink, KC+ purple) ……… ……… Canoparmelia nairobiensis (J. Stein. & Zahlbr.) Elix & Hale
Upperside emaculate; medulla with protocetraric acid (Pd+ orange-red).……… ………Canoparmelia somaliensis (Müll. Arg.) Elix & Hale
Key to species of Hypotrachyna (Vain.) Hale (37)
Lobes pale grey or pale yellow above, black below, generally sublinear, sometimes irregularly incised. Rhizines black, sparingly to densely branched, the branching dichotomous or squarrose, often with unbranched rhizines immixed or dominating. Branched or unbranched rhizines or cilia may also be marginally situated. Apothecia sessile to substipitate, with imperforate disc. Pycnoconidia bifusiform.
1 Soredia, isidia and dactyls absent ………2
Soredia, isidia or dactyls present ………7
2(1) Medulla Pd+ orange → red ………3
Medulla Pd− ………4
3(2) Rhizines simple to sparingly branched; medulla K− (protocetraric acid); saxicolous species ……… ……… Hypotrachyna fissicarpa (Kurok.) Hale
Rhizines densely branched; medulla K+ red (salazinic acid); corticolous species ……… Hypotrachyna sublaevigata (Nyl.) Hale
4(2) Rhizines mainly simple; di-O-methylgyrophoric acid and related substances (‘horrescens complex’Footnote 1) present ……… ……… . Hypotrachyna damaziana (Zahlbr.) Krog & Swinscow
Rhizines distinctly branched; chemistry otherwise ………5
5(4) Medulla C+ rose (gyrophoric acid) ……… Hypotrachyna scytophylla (Kurok.) Hale
Medulla C+ yellow-orange or C− ………6
6(5) Rhizines moderately branched; medulla KC+ orange, barbatic acid, 4-O-demethylbarbatic acid and obtusatic acid………Hypotrachyna ducalis (Jatta) Hale
Rhizines densely dichotomously branched; medulla KC+ orange, barbatic acid (major) obtusatic acid (minor) ……… ……… Hypotrachyna kenyana Kirika et al.
7(1) Thallus with isidia or closed dactyls ………8
Thallus with soredia or open dactyls ………16
8(7) Thallus with closed dactyls; substances in the lividic acid complex present ……… ……… Hypotrachyna polydactyla (Krog & Swinscow) T. H. Nash
Thallus with isidia; chemistry otherwise ………9
9(8) Medulla Pd+ orange ………10
Medulla Pd− ………11
10(9) Upper cortex yellow (usnic acid); medulla, norstictic and galbinic acids present………. . . . Hypotrachyna microblasta (Vain.) Hale
Upper cortex grey (atranorin); medulla K+ red, Pd+ orange, salazinic acid, protolichesterinic acid present ……… ………Hypotrachyna vexans (Zahlbr. ex W. L. Culb. & C. F. Culb.) Divakar et al.
11(9) Isidia with conspicuous apical and lateral cilia, KC+ rose, ‘horrescens complex’ ……… ………Hypotrachyna horrescens (Taylor) Krog & Swinscow
Isidia without or with inconspicuous cilia ………12
12(11) Medulla C+ rose (gyrophoric acid complex) ………13
Medulla C+ yellow-orange or C− ………15
13(12) Isidia in scattered submarginal and laminal groups; lobes 3–6 mm wide ……… ……… Hypotrachyna spathulata (Kurok.) Krog & Swinscow
Isidia crowded, covering most of the thallus; lobe width various ………14
14(13) Rhizines mainly simple; lobes short and 1–3 mm wide ……… Hypotrachyna minarum (Vain.) Krog & Swinscow
Rhizines frequently branched; lobes elongate and 2–3 mm wide (on twigs), or short and more than 5 mm wide (on tree trunks and rock) ……… Hypotrachyna neodissecta (Hale) Hale
15(12) Rhizines densely branched; medulla KC− (fatty acids) ………Hypotrachyna costaricensis (Nyl.) Hale
Rhizines moderately branched; medulla KC+ orange, barbatic acid, KC+ yellow- orange, 4-O-demethylbarbatic acid, faint traces of obtusatic and norobtusatic acids ……… Hypotrachyna orientalis (Hale) Hale
16(7) Upper cortex yellow (usnic acid) ………17
Upper cortex grey (usnic acid absent) ………19
17(16) Soralia subapical, subcapitate, with abundant soredia, salazinic acid present ………18
Soralia laminal, pustular, usually with sparse soredia ……… Hypotrachyna meyeri (Zahlbr.) Streim.
18(17) Norstictic acid present ………Hypotrachyna sinuosa (Sm.) Hale
Norstictic acid absent………Hypotrachyna meridionalis Kirika et al.
19(16) Medulla pigmented yellow to salmon pink, pigment K−, barbatic and obtusatic acids present ……… ……… Hypotrachyna endochlora (Leight.) Hale
Medulla white, at most pigmented ochraceous in patches, pigment K+ purple ………20
20(19) Thallus with subapical soralia ………21
Thallus with mainly laminal soralia, pustules, or open dactyls ………30
21(20) Medulla Pd+ orange or red ………22
Medulla Pd− ………24
22(21) Medulla K− (fumarprotocetraric acid) except for pigmented areas, K+ purple . . . . Hypotrachyna gondylophora (Hale) Hale
Medulla K+ red (salazinic acid) ………23
23(22) Soralia subcapitate; rhizines densely branched ……… Hypotrachyna brevirhiza (Kurok.) Hale
Soralia diffusely spreading; rhizines mainly simple ……… Hypotrachyna swinscowii (Hale) Krog & Swinscow
24(21) Medulla C+ rose or red ………25
Medulla C+ yellow-orange or C− ………28
25(24) Rhizines sparingly branched; gyrophoric acid present ………26
Rhizines densely branched; soralia subcapitate; chemistry various ………27
26(25) Soralia diffusely spreading, subapical; soredia green, powdery ……… Hypotrachyna revoluta (Flörke) Hale
Soralia subcapitate, subapically, marginally, or laminally situated in distal parts of the lobe; soredia coarsely granular ……… ……… . Hypotrachyna catawbiensis (Degel.) Divakar et al.
27(25) Upper cortex often maculate; evernic and lecanoric acids present ………Hypotrachyna rockii (Zahlbr.) Hale
Upper cortex emaculate; anziaic acid present ……… Hypotrachyna producta Hale
28(24) Upper cortex maculate; medulla KC+ orange with barbatic acid ………29
Upper cortex emaculate; thallus 10 cm or more diam.; medulla KC+ red, alectoronic and α-collatolic acids present ……… ……… Hypotrachyna densirhizinata (Kurok.) Hale
29(28) K+ red, 4-O-demethylbarbatic acid and obtusatic acid (+) present ……… Hypotrachyna laevigata (Sm.) Hale
K−, KC+ pale yellow, 4-O-demethylbarbatic acid absent, obtusatic acid (+) present ……… ………Hypotrachyna nyandaruaensis Kirika et al.
30(20) Rhizines mainly simple; K+ purple pigment absent ………31
Rhizines moderately branched; K+ purple pigment usually present ………34
31(30) Thallus closely adnate; lobes less than 1.5 mm wide; with open dactyls, situated laminally, bursting open at maturity without the formation of soredia ……… Hypotrachyna spumosa (Asah.) Krog & Swinscow
Thallus ±loosely attached; lobes more than 2 mm wide ………32
32(31) Thallus sorediate; soralia laminal and marginal; soredia farinose; medulla Pd+ orange, salazinic acid, protolichesterinic acid ……… ……… . Hypotrachyna sorocheila (Vain.) Divakar et al.
Thallus pustulate ………33
33(32) Pustules in part subapical, in part laminal, without soredia; medulla C− or fleetingly pale pink, ‘horrescens complex’ present ……… ……… Hypotrachyna subfatiscens (Kurok.) Krog & Swinscow
Pustules laminal, often near the lobe margins, with soredia; medulla distinctly C+ rose, gyrophoric acid present ……… ……… Hypotrachyna afrorevoluta (Krog & Swinscow) Krog & Swinscow
34(30) Cortex K−, UV+ bright yellow (lichexanthone) ……… Hypotrachyna formosana (Zahlbr.) Hale
Cortex K+ yellow, UV− (atranorin) ………35
35(34) Medulla C+ blood red (unidentified substances) ……… Hypotrachyna leiophylla (Kurok.) Hale
Medulla C− ………36
36(35) Medulla Pd+ orange-red, UV− (protocetraric acid) ………Hypotrachyna croceopustulata (Kurok.) Hale
Medulla Pd+ pale yellow, UV+ bluish white (lividic acid complex) ……… Hypotrachyna immaculata (Kurok.) Hale
Key to species of Parmotrema Massal. (65)
Lobes in most species widely rotund apically, pale grey or pale yellow above, pale to dark brown to black below, with brown, white, or mottled marginal zone. Marginal cilia present or absent. Rhizines unbranched or rarely bifurcate or squarrose, generally sparse or absent towards periphery of lobes, rarely dimorphous (in part long and coarse, in part short and slender). Apothecia substipitate to stipitate, disc perforate or imperforate. Pycnoconidia sublageniform or filiform.
1 Soralia, isidia, phyllidia and dactyls absent ………2
Soralia, isidia, phyllidia, or dactyls present ………35
2(1) Marginal cilia absent ………3
Marginal cilia present ………5
3(2) Apothecia imperforate; medulla C−, Pd+ orange-red (protocetraric acid) ……… Parmotrema zollingeri (Hepp) Hale
Apothecia perforate; medulla C+ red, Pd− (lecanoric acid) ………4
4(3) Thallus saxicolous, strongly attached; lobes less than 1 cm wide ……… Parmotrema soyauxii (Müll. Arg.) Hale
Thallus normally corticolous, loosely attached; lobes more than 1 cm wide ……… Parmotrema andinum (Müll. Arg.) Hale
5(2) Medulla pigmented pale yellow, ochraceous, or salmon pink, pigment K− ………6
Medulla white, at most with patches of an ochraceous, K+ purple pigment near the lower cortex ………7
6(5) Apothecia imperforate, with a dentate-ciliate thalline margin; medulla UV+ (undetermined substances); coastal species ……… ………Parmotrema pigmentiferum (Krog & Swinscow) Krog & Swinscow
Apothecia perforate, with a smooth, eciliate thalline margin; medulla UV− (gyrophoric acid); upland species……… ……… Parmotrema subcoloratum (Hale) Hale
7(5) Upper cortex with a reticulate pattern of maculae and cracks; rhizines in part squarrose; salazinic acid present ……… ……… Parmotrema cetratum (Ach.) Hale
Upper cortex without a reticulate pattern of maculae and cracks; rhizines not squarrose; salazinic acid present or absent ……… ………8
8(7) Underside with a distinct, white marginal zone ………9
Underside with a brown or mottled marginal zone ………13
9(8) Apothecia perforate, medulla UV− ………10
Apothecia mainly imperforate; medulla UV+ ………12
10(9) Underside almost entirely white; medulla C−, KC− (protolichesterinic acid) ……… Parmotrema leonis Krog & Swinscow
Underside black in the centre, white peripherally; medullary reactions various………11
11(10) Lobe margins flat or revolute; medulla C+ red (lecanoric acid) ………Parmotrema hololobum (Hale) Hale
Lobe margins ascending; medulla C− (norlobaridone and/or protolichesterinic acid) ……… ……… Parmotrema abessinicum (Kremp.) Hale
12(9) Spores < 20 μm long; alectoronic acid present ………Parmotrema uberrimum (Hue) Hale
Spores > 20 μm long; both alectoronic and α-collatolic acids present ……… ………Parmotrema durumae (Krog & Swinscow) Krog & Swinscow
13(8) Apothecia present ………14
Apothecia absent ………24
14(13) Spores > 20 μm long ………15
Spores < 20 μm long ………17
15(14) Upper cortex emaculate; apothecia imperforate ……… Parmotrema durumae (Krog & Swinscow) Krog & Swinscow
Upper cortex distinctly maculate; apothecia perforate or imperforate ………16
16(15) Medulla UV+ (alectoronic acid, ±α-collatolic acid, ±gyrophoric acid) ……… Parmotrema nilgherrense (Nyl.) Hale
Medulla UV− (gyrophoric acid and/or norlobaridone, ±norstictic acid) ……… Parmotrema eunetum (Stirt.) Hale
17(14) Upper cortex distinctly maculate ………18
Upper cortex emaculate or faintly maculate ………20
18(17) Rhizines dimorphous; salazinic acid and norlobaridone present ……… Parmotrema erubescens (Stirt.) Krog & Swinscow
Rhizines uniform; chemical properties different ………19
19(18) Underside brown; medulla Pd+ orange (stictic and norstictic acids); coast and coastal lowlands species ……… ………Parmotrema aldabrense (C. W. Dodge) Hale
Underside black in the centre, white, mottled, or brown peripherally; medulla Pd− (norlobaridone and/or protolichesterinic acid); upland species………Parmotrema abessinicum (Kremp.) Hale
20(17) Cortex Pd+ sulphur yellow near the apothecia (psoromic acid present); medulla C+ rose (gyrophoric acid) ……… ………Parmotrema jacarandicola (Krog & Swinscow) Krog & Swinscow
Cortex at most Pd+ pale yellow (psoromic acid absent); medulla C+ or C−………21
21(20) Medulla UV+ (alectoronic acid) ………Parmotrema maclayanum (Müll. Arg.) Hale
Medulla UV− (alectoronic acid absent) ………22
22(21) Thallus saxicolous; apothecia imperforate; medulla Pd+ orange-red (fumarprotocetraric acid)……… ………Parmotrema taitae (Krog & Swinscow) Krog & Swinscow
Thallus normally corticolous; apothecia perforate; medulla Pd+ or Pd− (fumarprotocetraric acid absent) ………23
23(22) Lobe margins flat or revolute; pycnoconidia filiform; medulla C+ red (lecanoric acid) ……… ………Parmotrema hololobum (Hale) Hale
Lobe margins ascending; pycnoconidia sublageniform; thalline exciple rarely ciliate; medulla C− (norlobaridone and/or protolichesterinic acid) ……… Parmotrema abessinicum (Kremp.) Hale
24(13) Medulla Pd+ orange or red ………25
Medulla Pd− (but cortex may be Pd+ sulphur yellow, see (32) P. jacarandicola) and upper cortex distinctly maculate ………29
25(24) Thallus saxicolous; fumarprotocetraric acid present………Parmotrema taitae (Krog & Swinscow) Krog & Swinscow
Thallus normally corticolous; fumarprotocetraric acid absent ………26
26(25) Upper cortex distinctly maculate ………27
Upper cortex emaculate or faintly maculate ………31
27(26) Salazinic acid and norlobaridone present ………Parmotrema erubescens (Stirt.) Krog & Swinscow
Salazinic acid absent, norlobaridone present or absent ………28
28(27) Norstictic acid present in combination with gyrophoric acid and/or norlobaridone; montane forest species ……… ………Parmotrema eunetum (Stirt.) Hale
Norstictic acid present in combination with stictic acid; coastal species ………Parmotrema aldabrense (C. W. Dodge) Hale
29(24) Species of dry, well-lit lowland or upland habitats; medulla C− (norlobaridone and/or protolichesterinic acid) ……… ……… Parmotrema abessinicum (Kremp.) Hale
Species of montane forests and the alpine zone ………30
30(29) Medulla UV+ (alectoronic acid, ±α-collatolic acid, ±gyrophoric acid) ………Parmotrema nilgherrense (Nyl.) Hale
Medulla UV− (gyrophoric acid and/or norlobaridone) ……… Parmotrema eunetum (Stirt.) Hale
31(26) Medulla C+ rose or red ………32
Medulla C−; substances in the lividic acid complex absent; norlobaridone and/or protolichesterinic acid or alectoronic acid, ±α-collatolic acid present ………33
32(31) Lecanoric acid present ………Parmotrema hololobum (Hale) Hale
Gyrophoric acid present; pycnoconidia filiform; psoromic acid present in association with apothecia ……… ……… Parmotrema jacarandicola (Krog & Swinscow) Krog & Swinscow
33(31) Medulla UV− (norlobaridone and/or protolichesterinic acid) ………Parmotrema abessinicum (Kremp.) Hale
Medulla UV+ (alectoronic acid, ±α-collatolic acid) ………34
34(33) Lobes mainly 1–2 cm wide; thallus corticolous or saxicolous; upland species above c. 1000 m altitude ……… ……… Parmotrema maclayanum (Müll. Arg.) Hale
Lobes < 1 cm wide; thallus corticolous; coastal and lowland species below c. 1000 m altitude ……… ………Parmotrema durumae (Krog & Swinscow) Krog & Swinscow
35(1) Isidia (including sorediate isidia), phyllidia, or dactyls present ………36
Isidia, phyllidia and dactyls absent; soralia present . ………50
36(35) Marginal cilia absent ………37
Marginal cilia present ………40
37(36) Medulla with protocetraric acid (Pd+ orange-red) and fatty acid, cortex with atranorin; lobes 1–2 mm wide, rounded, flat or convex; closed dactyls and crescent-shaped folds covering most of the thallus; upperside maculate; underside black to the margins; saxicolous ……… Parmotrema zimbabwense (Hale) Kirika et al.
Medulla Pd− ………38
38(37) Thallus large, loosely attached to tree bark or rock; isidia cylindrical and granular, or dactyls present; medulla C+ red (lecanoric acid) ………Parmotrema tinctorum (Nyl.) Hale
Thallus small, strongly attached to rock; only dactyls or coarse isidia present; medulla C+ or C− ………39
39(38) Medulla C+ red (lecanoric acid) ……… ……… Parmotrema stuhlmannii (C. W. Dodge) Krog & Swinscow
Medulla C− (physodic acid) ……… . Parmotrema tsavoense (Krog & Swinscow) Krog & Swinscow
40(36) Thallus yellow-green (usnic acid present) ……… Parmotrema nyasense (C. W. Dodge) R. S. Egan comb. nov. [MycoBank No.: MB 844542] basionym: Parmelia nyasensis C. W. Dodge, Annals of the Missouri Botanical Garden 46, 126 (1959). The nomenclatural novelty in Egan et al., Bibliotheca Lichenologica 110, 383 (2016) is published here by R. S. Egan.
Thallus grey (usnic acid absent) ………41
41(40) Upper cortex with a reticulate pattern of maculae and cracks; rhizines in part squarrose ……… ………Parmotrema subisidiosum (Müll. Arg.) Hale
Upper cortex without a reticulate pattern of maculae and cracks; rhizines not squarrose ………42
42(41) Medulla pigmented pale to bright yellow or orange, pigment K− ………43
Medulla white, at most with patches of an ochraceous, K+ purple pigment near the lower cortex; isidia cylindrical, submarginally or laminally situated ………44
43(42) Medulla pigmented bright yellow to orange throughout; cylindrical isidia present; coastal species ……… ………Parmotrema sulphuratum (Nees & Flotow) Hale
Medulla pigmented pale yellow, but sometimes inapparent; open dactyls present; lower montane forest species ……… ……… Parmotrema cryptoxanthum (des Abb.) Hale
44(42) Upperside distinctly maculate ………45
Upperside emaculate or faintly maculate ………46
45(44) Rhizines dimorphous; salazinic acid and norlobaridone present; upland species ……… ……… Parmotrema subtinctorium (Zahlbr.) Hale
Rhizines uniform; stictic and norstictic acids present; coastal species ……… ……… Parmotrema kwalense (Krog & Swinscow) Krog & Swinscow
46(44) Thallus coriaceous; isidia mainly laminal, never becoming sorediate ………47
Thallus usually membranaceous; isidia mainly submarginal, often becoming sorediate-granular ………48
47(46) Medulla C+ rose, Pd−, UV− (gyrophoric acid) ……… Parmotrema pseudocrinitum (Abbayes) Hale
Medulla C−, Pd+ orange, UV+ intensely yellow (salazinic acid, lichexanthone) ……… Parmotrema ultralucens (Krog) Hale
48(46) Upper cortex usually continuous; isidia rarely sorediate; medulla Pd+ orange (stictic acid) ……… ……… Parmotrema crinitum (Ach.) M. Choisy
Upper cortex fragile and flaking; isidia often sorediate; medulla Pd− ………49
49(48) Medulla C+ rose, UV− (gyrophoric acid)……… Parmotrema lophogenum (Abbayes) Hale
Medulla C−, UV+ (alectoronic acid) ……… Parmotrema mellissii (C. W. Dodge) Hale
50(35) Marginal cilia absent ………51
Marginal cilia present ………62
51(50) Saxicolous ………52
Corticolous ………55
52(51) Medulla Pd+ orange-red (protocetraric acid) ………Parmotrema pardii (Krog & Swinscow) Krog & Swinscow
Medulla Pd− ………53
53(52) Medulla C− (fatty acids) ……… Parmotrema praesorediosum (Nyl.) Hale
Medulla C+ red (lecanoric acid) ………54
54(53) Thallus small, coriaceous, strongly attached; upper cortex emaculate, shiny ………Parmotrema defectum (Hale) Hale
Thallus usually large, relatively thin, loosely attached; upper cortex faintly maculate, often matt ……… ……… Parmotrema austrosinense (Zahlbr.) Hale
55(51) Thallus yellow or yellowish grey (usnic acid present); medulla Pd+ orange-red (protocetraric acid) ………56
Thallus pale grey (usnic acid absent); medulla Pd+ or Pd− ………58
56(55) Thallus bright yellow to yellow-green; atranorin absent ……… Parmotrema apricum (Krog & Swinscow) Krog & Swinscow
Thallus yellowish grey; atranorin present ………57
57(56) Echinocarpic acid and various unknowns present ……… Parmotrema dilatatum (Vain.) Hale
Echinocarpic acid and unknowns absent ……… Parmotrema ravum (Krog & Swinscow) Sérus.
58(55) Medulla C+ red (lecanoric acid) ……… Parmotrema austrosinense (Zahlbr.) Hale
Medulla C− ………59
59(58) Medulla Pd− (fatty acids) ……… Parmotrema praesorediosum (Nyl.) Hale
Medulla Pd+ orange or red ………60
60(59) Medulla K+ red (salazinic acid)………Parmotrema cristiferum (Taylor) Hale
Medulla K+ pale brown (protocetraric acid) ………61
61(60) Lobes 0.8–1.5(–2) cm wide, rarely sparingly ciliate, (cilia 0.2–0.5 mm long); upperside emaculate (or faintly maculate); soralia marginal and submarginal, soredia granular; apothecia laminal, substipitate, thalline exciple sorediate; pycnoconidia sublageniform ……… Parmotrema gardneri (C. W. Dodge) Sérus.
Lobes 0.8–3 mm wide, eciliate; upperside maculate; soralia laminal, punctiform, more or less confluent in central parts; apothecia and pycnidia not seen in material from Kenya ……… Parmotrema epileucum (Hale) Kirika et al.
62(50) Upper cortex fragile and flaking; soralia erupting in a pustular fashion ………63
Upper cortex continuous; soralia rarely pustular ………66
63(62) Medulla pigmented pale yellow; echinocarpic acid and fatty acids present ………Parmotrema cryptoxanthum (Abbayes) Hale
Medulla white; chemistry otherwise ………64
64(63) Medulla Pd+ orange, UV− (stictic acid) ………Parmotrema bangii (Vain.) Hale
Medulla Pd−, UV+ (alectoronic acid) ………65
65(64) Soralia pustular, without isidia ………Parmotrema rimulosum (C. W. Dodge) Hale
Soralia not pustular, but occasionally interspersed with isidia ………Parmotrema mellissii (C. W. Dodge) Hale
66(62) Medulla pigmented (ochraceous yellow to salmon pink), K− ………67
Medulla white, K− (or K+ purple, if patches of an ochraceous yellow pigment occur near the lower cortex) ………68
67(66) Medulla C+ rose in upper parts (gyrophoric acid) ………Parmotrema permutatum (Stirt.) Hale
Medulla C− (fatty acids) ……… Parmotrema araucariarum (Zahlbr.) Hale
68(66) Upper cortex with a reticulate pattern of maculae and cracks; rhizines in part squarrose ……… ………Parmotrema reticulatum (Taylor) M. Choisy
Upper cortex lacking a reticulate pattern of maculae and cracks; rhizines not squarrose ………69
69(68) Underside with a distinct, white marginal zone ………70
Underside with a brown or mottled marginal zone ………72
70(69) Lobes deeply divided, with sublinear laciniae; medulla K+ red, Pd+ orange (norstictic, galbinic and salazinic acids); coastal species ……… Parmotrema parahypoptorum (W. L. Culb.) Hale
Lobes more or less rounded, sublinear laciniae absent; medulla K−, Pd−; inland species ………71
71(70) Underside black in the centre, white peripherally; medulla UV− (norlobaridone and/or protolichesterinic acid) ……… ……… Parmotrema hababianum (Gyeln.) Hale
Underside almost entirely white; medulla UV+ (alectoronic acid) ……… ……… Parmotrema louisianae (Hale) Hale
72(69) Rhizines dimorphous, often extending to the margins ………73
Rhizines uniform, rarely extending to the margins ………74
73(72) Soralia marginal; medulla Pd+ orange, KC− (salazinic acid) or Pd−, KC+ red (norlobaridone) ……… ……… Parmotrema subsumptum (Nyl.) Hale
Soralia laminal; medulla Pd−, KC− (fatty acids) ……… Parmotrema pilosum (Stizenb.) Krog & Swinscow
74(72) Upper cortex distinctly maculate ………75
Upper cortex emaculate or faintly maculate ………76
75(74) Medulla UV+ (alectoronic acid, ±α-collatolic acid, ±gyrophoric acid) ……… Parmotrema lobulascens (J. Stein.) Hale
Medulla UV− (gyrophoric acid and/or norlobaridone, ±norstictic acid)……… Parmotrema subschimperi (Hale) Hale
76(74) Thallus saxicolous ………77
Thallus normally corticolous ………78
77(76) Medulla UV+ (alectoronic acid) ………Parmotrema poolii (C. W. Dodge) Krog & Swinscow
Medulla UV−, Pd+ orange-red (fumarprotocetraric and protocetraric acids) ……… ……… Parmotrema pseudograyanum (Hale) Sérus.
78(76) Medulla Pd+ orange → red ………79
Medulla Pd−; soralia Pd− or Pd+ yellow ………83
79(78) Protocetraric acid present ………80
Protocetraric acid absent ………82
80(79) Medulla C+ rose, gyrophoric acid present ……… Parmotrema umbrosum (Krog & Swinscow) Krog & Swinscow
Medulla C−, gyrophoric acid absent ………81
81(80) Cilia well developed; medulla UV+ (alectoronic or α-collatolic acid) or UV− (protolichesterinic acid) ……… ……… Parmotrema subarnoldii (Abbayes) Hale
Cilia poorly developed, present only in the lobe axils; medulla UV− (±undetermined fatty acids) ……… ……… Parmotrema gardneri (C. W. Dodge) Sérus.
82(79) Stictic acid present ……… Parmotrema perlatum (Huds.) M. Choisy
Salazinic acid present ……… Parmotrema cristiferum (Taylor) Hale
83(78) Soralia Pd+ sulphur yellow (psoromic acid)………Parmotrema direagens (Hale) Hale
Soralia Pd− or at most Pd+ pale yellow (psoromic acid absent) ………84
84(83) Medulla UV+ (alectoronic acid)………Parmotrema poolii (Dodge) Krog & Swinscow
Medulla UV− ………85
85(84) Medulla C− (norlobaridone and/or protolichesterinic acid)……… Parmotrema hababianum (Gyeln.) Hale
Medulla C+ rose or red ………86
86(85) Lecanoric acid present ……… Parmotrema cooperi (Steiner & Zahlbr.) Sérus.
Gyrophoric acid present ………87
87(86) Soralia often ciliate, soredia granular; fatty acids present ………Parmotrema lophogenum (Abbayes) Hale
Soralia eciliate, soredia farinose; fatty acids absent………88
88(87) Norlobaridone present………Parmotrema indicum Hale
Norlobaridone absent ……… Parmotrema sancti-angelii (Lynge) Hale
Key to the species of Punctelia Krog (9)
Upperside with laminal, punctiform pseudocyphellae. Rhizines simple. Medulla white except for an ochraceous, K+ purple pigment (skyrin) in some species. Apothecia with imperforate disc. Pycnoconidia unciform (rod-shaped with a single hook-shaped end), bifusiform, or filiform.
1 Soredia, isidia and phyllidia absent ………2
Soredia, isidia, or phyllidia present ………3
2(1) Underside pale brown; lecanoric acid present ……… Punctelia semansiana (W. L. Culb. & C. F. Culb.) Krog
Underside black; gyrophoric acid present ……… Punctelia subpraesignis (Nyl.) Krog
3(1) Isidia or phyllidia present, soredia absent ………4
Isidia and phyllidia absent, soredia present ………5
4(3) Thallus with low, papilliform or sparingly branched isidia with a dull surface; always on rock ……… ………Punctelia punctilla (Hale) Krog
Thallus with coralloid isidia or phyllidia with a glossy cortex; underside pale brown; lecanoric acid present; commonly on trees ……… Punctelia rudecta (Ach.) Krog
5(3) Medulla C+ rose or red, KC+ red ………6
Medulla C−, KC−………8
6(5) Underside pale brown; medulla C+ red (lecanoric acid) ……… Punctelia subrudecta (Nyl.) Krog
Underside black; medulla C+ rose (gyrophoric acid)………7
7(6) Upperside predominantly grey; mainly corticolous; widespread ……… Punctelia borreri (Sm.) Krog
Upperside with a pronounced brown marginal zone; saxicolous in upper montane-alpine region; rare……… ……… Punctelia stictica (Duby) Krog
8(5) Underside pale brown; caperatic acid present ………Punctelia neutralis (Hale) Krog
Underside black; undetermined fatty acids present……… Punctelia reddenda (Stirt.) Krog
Key to species of Xanthoparmelia (Vain.) Hale (29)
Lobes irregularly incised, truncate, or rounded, separate to imbricate, 0.1–8 mm wide, marginal cilia absent. Upperside pale yellowish green or brown. Medulla white to ochraceous. Underside pale to dark brown or black, rhizinate to the margin or with a bare marginal zone (or rarely without rhizines). Rhizines simple, often with pale, frayed tips. With or without isidia, without soredia and pseudocyphellae. Apothecia adnate to substipitate, disc imperforate. Pycnoconidia shortly bifusiform.
Saxicolous, often in high elevations at several thousand metres.
1 Isidia absent ………2
Isidia present ………12
2(1) Underside brown ………3
Underside black ………5
3(2) Lobes usually wider than 2 mm; medulla with fumarprotocetraric and/or protocetraric acid ………4
Lobes linear-elongate, almost completely terete, 0.5–1.5 mm wide; medulla with salazinic acid and norstictic acid (trace); cortex with usnic acid ……… Xanthoparmelia cylindriloba M. D. E. Knox
4(3) Lobes imbricate, 0.8–4(–8) mm wide; medulla with fumarprotocetraric acid and associated substances; cortex with usnic acid ……… ………Xanthoparmelia phaeophana (Stirt.) Hale
Lobes mainly adjacent, 2–4 mm wide; medulla with protocetraric acid; cortex with usnic acid ……… ……… Xanthoparmelia austroafricana (Stirt.) Hale
5(2) Thallus subcrustose, tightly adnate to the substratum; lobes 0.5–1 mm wide, reddish brown; norstictic acid present……… ……… Xanthoparmelia nakuruensis (Essl.) O. Blanco et al.
Thallus foliose, loosely attached to the substratum ………6
6(5) Upperside distinctly and evenly maculate, pale yellow; protocetraric acid present; lobes imbricate, ascending, repeatedly branched, sublinear, slightly convex, 0.5–1.5 mm wide; medulla with protocetraric acid, ±fatty acid; cortex with usnic acid; below c. 2500 m alt. ……… . Xanthoparmelia hypoleia (Nyl.) Hale
Upperside emaculate or at most maculate here and there; chemistry various, protocetraric acid absent; above c. 3000 m alt. ………7
7(6) Salazinic acid present. ………8
Salazinic acid absent. ………9
8(7) Thallus pulvinate ………10
Thallus not pulvinate, membranous, lobes sublinear, 2–4(–5) mm wide, contiguous to imbricate, emaculate, slightly to moderately rhizinate; cortex with usnic acid ……… . Xanthoparmelia tasmanica (Hook. f. & Taylor) Hale
9(7) Lobes up to 8 mm wide, white-maculate, rhizinate to the margins; cortex with usnic acid ……… ……… Xanthoparmelia africana Hale
Lobes 0.8–2 mm wide, black rimmed, emaculate, sparsely to moderately rhizinate; cortex with usnic acid ……… ……… Xanthoparmelia salkiboensis Hale
10(8) Lobes sublinear, secondary laciniae lacking, 2–4(–5) mm wide, contiguous to imbricate, emaculate, sparsely rhizinate; medulla with fumarprotocetraric acid and associated substances; cortex with usnic acid ……… ……… Xanthoparmelia rogersii Elix & J. Johnst.
Lobes 0.1–0.3 mm in the centre, peripherally 2–3(–4) mm wide, with a rhizine-free marginal zone at apices; medulla with different substances ………11
11(10) Medulla K+ red (norstictic acid); lobes plane or in part subterete, 0.1–2(–3) mm wide; cortex with usnic acid……… ……… Xanthoparmelia kiboensis (C. W. Dodge) Krog & Swinscow
Medulla K− (fatty acids); lobes plane, 0.2–4 mm; cortex with usnic acid ………Xanthoparmelia atroventralis (Hale) Hale
12(l) Thallus adnate to appressed; lobes adjacent, normally < 1.5 mm wide (however, X. treurensis and X. verrucigera with wider lobes key out here)………13
Thallus adnate to loosely attached; lobes often imbricate, normally > 1.5 mm wide (however, X. endochrysea with narrower lobes keys out here)………23
13(12) Underside black ………14
Underside brown ………19
14(13) Stictic acid present ………15
Stictic acid absent ………17
15(14) Lobes 0.2–0.8 mm wide, irregularly incised, with a narrow black margin; isidia globose, often bursting open, but not becoming sorediose; cortex with usnic acid ……… Xanthoparmelia congensis (J. Steiner) Hale
Lobes wider than 1 mm, without black margin; isidia cylindrical ………16
16(15) Lobes 1–3 mm wide, subirregular, contiguous to imbricate; verrucigeric acid present; cortex with usnic acid ……… ………Xanthoparmelia verrucigera (Nyl.) Hale
Lobes 2–5 mm wide, sublinear, contiguous; verrucigeric acid absent; cortex with usnic acid ……… ………Xanthoparmelia treurensis Hale et al.
17(14) Lobes sublinear, 1.8–4 mm wide, contiguous to densely imbricate, weakly white-maculate; isidia cylindrical, becoming dense and coralloid branched with age; salazinic acid present; cortex with usnic acid ……… ………Xanthoparmelia australasica D. J. Galloway
Lobes 0.5–1.5 mm wide ………18
18(17) Thallus moderately to closely adnate, medium to dark brown; lobes irregularly incised, more or less imbricate, (0.5–)1–1.5 mm wide; isidia cylindrical, rarely clavate, simple or branched; PQ-4 and related substances of the ‘quintaria’ type I; medulla K+ red, Pd+ pale yellow; cortex with usnic acid ………Xanthoparmelia kenyana (Essl.) O. Blanco et al.
Thallus adnate to appressed, pale yellow-green, darkening at the centre; lobes adjacent or somewhat overlapping, 0.7–1.3 mm, lobe ends irregularly incised; isida subglobose to shortly cylindrical, unbranched or rarely, sparingly branched; salazinic acid present; cortex with usnic acid ………Xanthoparmelia diadeta (Hale) Hale
19(13) Thallus yellowish grey or pale grey; cortex with atranorin ………20
Thallus yellow-green; cortex with usnic acid ………21
20(19) Lobes deeply divided; isidia usually darker than the thallus; apothecia often numerous, laminal, 1–2 mm diam.; pycnoconidia weakly bifusiform, 5–7 μm long; medulla with lecanoric acid (C+ red) ……… Xanthoparmelia annexa (Kurok.) Elix
Lobes irregularly incised, often black rimmed, more or less imbricate; isidia concolorous with the thallus, sometimes darker grey; mature apothecia and pycnidia not seen in material from Kenya; medulla with norlobaridone (KC+ purple), loxodin ……… ……… Xanthoparmelia subtortula (Hale) Elix
21(19) Isidia coarse, dissolving into agglomerates of corticate granules; medulla K+ yellow, Pd+ yellow-orange, stictic acid aggr.……… ……… Xanthoparmelia glomerulata Krog & Swinscow
Isidia cylindrical, slender ………22
22(21) Medulla white, K−, Pd−, KC+ purple, norlobaridone ……… Xanthoparmelia amplexula (Stirt.) Elix & Johnston
Medulla ochraceous, pigment K−; cortex with usnic acid; medulla with protocetraric acid, fumarprotocetraric acid (Pd+ orange-red) and two undetermined substances (trace amounts) ………Xanthoparmelia krogiae Hale & Elix
23(12) Underside black ………24
Underside brown ………26
24(23) Stictic acid present ………Xanthoparmelia lusitana (Nyl.) Krog
Stictic acid absent ………25
25(24) Isidia uniformly cylindrical; medulla K− (fatty acids) ……… Xanthoparmelia meruensis Krog & Swinscow
Isidia cylindrical, semiglobular, claviform, or spatulate-lobulate; medulla K+ red (salazinic acid) ……… ……… Xanthoparmelia tinctina (Maheu & A. Gillet) Hale
26(23) Thallus adnate or tightly adnate on rock; medulla Pd+ pale orange ………27
Thallus loosely attached; isidia mostly slender; medulla Pd+ yellow-orange or orange-red ………28
27(26) Thallus tightly adnate, lobes 0.7–1.3 mm wide, moderately isidiate; hypoprotocetraric acid present ……… ……… Xanthoparmelia endochrysea (Müll. Arg.) Hale
Thallus adnate, lobes 2–3 mm wide; isidia coarse; hypoprotocetraric acid present ……… ……… Xanthoparmelia weberi (Hale) Hale
28(26) Medulla K+ pale brown, fumarprotocetraric acid present ………Xanthoparmelia subramigera (Gyeln.) Hale
Medulla K+ red, salazinic acid present ………Xanthoparmelia mexicana (Gyeln.) Hale
Discussion
The key obviously contains some species with only a preliminary taxonomic status. Several recent papers by Kirika et al. (Kirika et al. Reference Kirika, Divakar, Crespo, Gatheri, Mugambi, Leavitt, Moncada and Lumbsch2016a, Reference Kirika, Divakar, Crespo, Mugambi, Orock, Leavitt, Gatheri and Lumbschb, Reference Kirika, Divakar, Crespo, Leavitt, Mugambi, Gatheri and Lumbschc, Reference Kirika, Divakar, Buaruang, Leavitt, Crespo, Gatheri, Mugambi, Benatti and Lumbsch2017a, Reference Kirika, Divakar, Leavitt, Buaruang, Crespo, Mugambi, Gatheri and Lumbschb, Reference Kirika, Divakar, Crespo and Lumbsch2019) contain valuable novelties; these have been revealed by the application of molecular genetic methods on East African lichens which emphasizes the importance of studying further tropical collections to clarify unanswered questions. The most important changes were necessary to determine the status of Pseudoparmelia species, most of which were recombined as Canoparmelia, Flavoparmelia, Parmelia, Parmotrema, Relicina or Xanthoparmelia. Parmotrema nyasense (C. W. Dodge) R. S. Egan comb. nov. is formally recombined in this publication. Confirmation of this change by molecular genetic analysis is necessary as soon as fresh collections are available. A new combination for Pseudoparmelia usambarensis (J. Steiner & Zahlbr.) Krog & Swinscow was incorrectly cited in Index Fungorum Partnership (2022) as ‘Parmotrema usambarense (J. Steiner & Zahlbr.) Buaruang et al. [as ‘usambarensis’], MycoKeys 28 [actually 23], 58 (2017)’, and incorrectly listed in Buaruang et al. (Reference Buaruang, Boonpragob, Mongkolsuk, Sangvichien, Vongshewarat, Polyiam, Rangsiruji, Saipunkaew, Naksuwankul and Kalb2017) as ‘Parmotrema usambarense (J. Steiner & Zahlbr.) Krog & Swinscow, Lichenologist 19, 424 (1987)’, since this refers to the publication of Pseudoparmelia usambarense (J. Steiner & Zahlbr.) Krog & Swinscow, as maintained here in the newly presented key. Several other taxa may change their taxonomic status as a result of further research. Some species treated earlier as synonyms (e.g. Pseudoparmelia caroliniana (Nyl.) Hale and P. concrescens (Vain.) Hale) according to the chemical concept of Swinscow & Krog (Reference Swinscow and Krog1988) are independently added to the key (cf. Culberson Reference Culberson1993). The chemical variety (2) of Flavoparmelia soredians sensu Swinscow & Krog (Reference Swinscow and Krog1988) may represent smaller specimens of F. caperata with narrower lobes, or another species; it has therefore been omitted from the key. In other supposedly related species (e.g. the apotheciate Parmotrema abessinicum and the sorediate P. hababianum) with similar chemical compositions, different hypotheses may be reached. Several earlier literature sources (e.g. Hale Reference Hale1974a, Reference Haleb, Reference Halec, Reference Haled; Elix et al. Reference Elix, Johnston and Vernon1986; Kurokawa Reference Kurokawa1994) need to be restudied to revise or reinstate the various taxonomic concepts (Egan et al. Reference Egan, Pérez-Pérez and Nash2016; Del-Prado et al. Reference Del-Prado, Buaruang, Lumbsch, Crespo and Divakar2019; Diederich & Ertz Reference Diederich and Ertz2020). Furthermore, the molecular genetic and regulatory background of the biosynthetic pathways must be better understood (cf. Singh et al. Reference Singh, Armaleo, Grande F and Schmitt2021) in order to explain chemotype diversity.
Some species indicated as Hypotrachyna sp. A and sp. B, Neofuscelia sp. A, Parmotrema sp. A and sp. B (Swinscow & Krog Reference Swinscow and Krog1988) or certain species mentioned in other publications (e.g. Kirika et al. Reference Kirika, Divakar, Crespo, Leavitt, Mugambi, Gatheri and Lumbsch2016c, Reference Kirika, Divakar, Crespo and Lumbsch2019) as existing but not yet formally described, will no doubt increase the number of species in the near future, but further fieldwork will most certainly result in an increased number of newly described species.
Lichenologically, Kenya is one of the best studied countries in Africa. The search word ‘Kenya’ in the database ‘Recent literature on lichens’ (Culberson et al. Reference Culberson, Egan, Esslinger, Hodkinson and Lendemer2022) resulted in 79 papers out of 52 174, while 645 papers were found for ‘tropical’ (563) + ‘tropics’ (82) or 805 for ‘Africa’. Thus c. 10% of publications from Africa originate from Kenyan material. However, discoveries of species new to science can be expected since tropical and African lichens are generally understudied.
Since our knowledge of lichenicolous fungi in East Africa is still limited (Farkas & Flakus Reference Farkas and Flakus2016; Suija et al. Reference Suija, Kaasalainen, Kirika and Rikkinen2018), research into possible host species is very important. The key presented here will support further field studies and the identification work that follows, and thus contribute to a better knowledge of both lichens and their lichenicolous fungi in Kenya and East Africa, as well as promote conservation studies and the practical use of bioactive lichen secondary metabolites.
Acknowledgements
The present work was supported by the National Research Development and Innovation Fund NKFI K 124341 and the Stipendium Hungaricum Scholarship (2020–2024). We express our special thanks to Prof. Mark R. D. Seaward (Bradford University, UK) for his advice and revision of the English text. The authors are also grateful to Dr László Lőkös (Hungarian Natural History Museum, Budapest) for reading the manuscript and for his useful advice.
Author ORCID
Edit Farkas, 0000-0002-5245-1079.
Competing Interests
The authors declare none.
Supplementary Material
To view Supplementary Material for this article, please visit https://doi.org/10.1017/S0024282922000299.
