Whilst checking on some types of species in the lichen genus Physma, I came upon the type of Physma reflectens (Nyl.) Zahlbr., which is based on Collema reflectens Nyl. (Fig.1). This proved to be an older name for Pannaria sorediata C. Knight which I reluctantly took up for a characteristic species in the Pannaria lurida group as I revised this in Australia (Jørgensen 2004). The reluctance was due to the epithet being based on a misunderstanding by the publishing author that the juvenile apothecia on the thalline margin were incipient soralia. Since the Code does not allow us to reject names only because they are inappropriate, and this was too minor a case to go to the cumbersome process of a proposal for rejection, I settled for keeping the name for a rather local species, which Vainio later (1921) aptly had named Pannaria involuta Vain. (due to the inwardly bent thalline margins).
Nylander obviously placed the species in the genus Collema because of the gelatinous thallus. However, otherwise both this and the other species of the Pannaria lurida group have the typical characters of the genus Pannaria (Jørgensen Reference Jørgensen1994), an amyloid hymenium with asci lacking internal, apical amyloid structures with simple spores, as well as containing pannarin in the thallus. This combination of characters is not known in Physma, which does not contain pannarin at all, but recently in molecular studies (Wedin et al.Reference Wedin, Wiklund, Jørgensen and Ekman2009) surprisingly proved to belong in the Pannariaceae.
The correct nomenclature for this characteristic lichen is accordingly as follows:
Pannaria reflectens (Nyl.) P. M. Jørg., comb. nov
Collema reflectens Nyl., Bull. Soc. Linn. Normandie ser.2, II: 43–44 (1868); type: New Caledonia, Wagap, Viellard (H-NYL 41724—holotype!).
Pannaria sorediata C. Knight in F. M. Bailey, Proc. Royal Soc. Queensland 1: 90 (1882); type: Queensland, without date, locality and collector (probably C. Knight) (WELT—hb. Knight, lectotype! selected by Jørgensen & Galloway Reference Jørgensen and Galloway1992: 316).
Pannaria involuta Vain., Ann. Acad. Sci. Fenn. Ser. A 15: 18–19 (1921); type: Philippines, Mindanao, Davao distr., Mt. Apo, E.B. Copeland 1090 (TUR- V 12215—holotype!).
Phytogeography. The discovery of this species in the coastal region of New Caledonia is not surprising, since it was previously known mainly from coastal forests in Queensland, Australia, where it has recently been collected. The most surprising, very disjunct record is that from a montane forest (at 1900 m) in the Philippines. This suggests the species may belong in the Australasian element, just like some other Pannariaceae [e.g., Pannaria molkenboeri (Mont.) Hue, see Jørgensen & Sipman Reference Jørgensen and Sipman2006], but further collections are needed to prove this. It is alarming that so few recent collections are known (none in New Caledonia and the Philippines), so this is a species which needs to be Red-listed.
I am indebted to the curators and directors of the herbaria cited who located and sent me the relevant material on loan. Arve Elvebakk, Tromsø, kindly supplied me with data on the type locality in New Caledonia. Further thanks go to Jan Berge and Beate Helle who took and assisted in preparing the photograph.