INTRODUCTION
The awareness about protecting species and habitats has increased and the biodiversity crisis has prompted rapid inventories at all levels. Ideally, full species inventories based on basic taxonomy and phylogenetic research (Wheeler, Reference Wheeler1995) including the abundance and distribution of species both at regional and global levels are the first steps for conservation planning. Certainly, protected areas provide the basis for the protection of whole ecosystems (Mora et al., Reference Mora, Andréfouët, Costello, Kranenburg, Rollo, Veron, Gaston and Myers2006) but in many cases, local biodiversity and levels of endemism are unknown and ignored (Brooks et al., Reference Brooks, Mittermeier, da Fonseca, Gerlach, Hoffmann, Lamoreux, Mittermeier, Pilgrim and Rodriguez2006). Coral reefs in western Pacific Panama (Gulf of Chiriquí) are among the most diverse in scleractinian and octocoral species in the Marine Conservation Corridor of the Eastern Tropical Pacific (Guzman et al., Reference Guzman, Guevara and Breedy2004, Reference Guzman, Benfield, Breedy and Mair2008; Guzman & Breedy, Reference Guzman and Breedy2008). This high diversity area of Panama encompasses more than 445 islands, islets, and over 2300 km of coastline creating atypical habitats suitable for several species if compared with others in the region. Seventy-five coral species are reported including 52 octocorals (Guzman & Breedy, Reference Guzman and Breedy2008; Guzman et al., Reference Guzman, Benfield, Breedy and Mair2008). Centred in the Gulf of Chiriquí is the 2025 km2 Coiba National Park marine protected area, containing most of the endemic octocoral species and is presumably a regional diversity hot spot (Guzman & Breedy, Reference Guzman and Breedy2008).
The genus Pacifigorgia Bayer, Reference Bayer1951 is one of the most diverse and abundant. Pacifigorgia includes reticulated fan-shaped gorgoniids. Historically, 18 species have been recognized, all restricted to the Pacific Ocean from southern California to Chile and the Galápagos Islands, except for one western Atlantic species (Breedy & Guzman, Reference Breedy and Guzman2002). Further taxonomic research has unveiled several new species increasing the list to a total of 34 worldwide (Breedy & Guzman, Reference Breedy and Guzman2003a, Reference Breedy and Guzmanb; Breedy & Guzman, Reference Breedy and Guzman2004; Williams & Breedy, Reference Williams and Breedy2004).
Herein, we describe a new species of Pacifigorgia from Coiba National Park, and discuss its relationship with other members of the genus. This discovery is a contribution to the biodiversity knowledge in the area.
MATERIALS AND METHODS
Specimens were collected by SCUBA diving, down to 40 m in depth at Punta Hermosa, Coiba Island National Park, Gulf of Chiriquí, Panama, and the population was visually assessed in terms of abundance and size-structure. One colony sample was preserved in alcohol, two others were air-dried, and small fragments were preserved in 95% ethanol for further (and ongoing) molecular studies. Sclerites were prepared for light and scanning electron microscopy (SEM) following the standard techniques for structural analysis (Bayer, Reference Bayer1961; Breedy & Guzman, Reference Breedy and Guzman2002). Comparative material was obtained from the Museo de Zoología, Universidad de Costa Rica (UCR) collection, and our recent collections in Costa Rica and Panama. Standard techniques for morphological studies were applied (Breedy & Guzman, Reference Breedy and Guzman2002) giving measurements of branches, meshes, and sclerites corresponding to the maximum size found. The terminology used in the description follows Bayer et al. (Reference Bayer, Grasshoff and Verseveldt1983) and Breedy & Guzman (Reference Breedy and Guzman2002). The holotype and paratypes are deposited in the UCR. The abbreviation STRI stands for the Smithsonian Tropical Research Institute.
Type species: Gorgonia stenobrochis Valenciennes, 1846, by original designation (Bayer, Reference Bayer1951: 94).
DESCRIPTION
Flabellate gorgoniids with reticulated colonies composed of a single or multiple fans growing in one or several planes. Fan sizes are from a few centimetres to up to 1 m in height and 1.2 m in width. They are attached to the substrate by encrusting, expanded holdfasts. Stems are absent or short. Midribs could be present or not. When present they are thick and cross the fans or thin, almost blended into the network. Networks are regular or irregular with meshes of various dimensions and shapes. Axes horny, with a cross-chambered central core that includes a network of organic filaments mineralized with microspheres of CHAp (carbonate hydroxylapatite). Calyces absent, polyps retract into dome-shaped coenenchymal mounds. Polyp-mounds are prominent or slightly raised above surface of the coenenchyme. Coenenchymal sclerites basically of two kinds, with a number of intermediate derivatives: spindles with acute, blunt, or irregular ends and several whorls of warty tubercles, can reach up to 0.2 mm in length; and capstans ornamented with different levels of complexity, can reach up to 0.09 mm in length. Anthocodial sclerites are flattened rods with smooth, scalloped, indented or lobed margins.
DISTRIBUTION
Eastern Pacific, from southern California to Chile and the Galápagos Islands; Atlantic coast, only one species (Pacifigorgia elegans (Milne Edwards & Haime, Reference Milne Edwards and Haime1857)) from Trinidad to Brazil (Bayer, Reference Bayer1951; Breedy & Guzman, Reference Breedy and Guzman2002).
Fig. 1. Pacifigorgia marviva sp. nov. (A–C) Holotype STRI 1185; (A) dry preserved, whole specimen; (B) in situ at Punta Hermosa, 38 m in depth; (C) detail of branches; (D) paratype, STRI 1184, alcohol preserved, detail of branches.
Fig. 2. Pacifigorgia marviva sp. nov. Holotype, spindles from the coenenchyme.
Fig. 3. Pacifigorgia marviva sp. nov. (A–C) Holotype, sclerites from the coenenchyme; (A) irregular spindles; (B) capstans, radiates; (C) crosses; (D) anthocodial rods.
TYPE MATERIAL
Holotype: dry specimen. (Punta Hermosa, Coiba Island, Gulf of Chiriquí, Panama; coordinates: 07°31.385′N 081°53.515′W; water depth: 37 m) [STRI 1185]. Collected by: O. Breedy and H.M. Guzman, 29 April 2010.
Paratypes: alcohol preserved specimen (same as the holotype; water depth: 35 m) [STRI 1184]. Collected by: O. Breedy and H.M. Guzman, 29 April 2010. Dry specimen (same as the holotype; water depth: 35 m) [STRI 1185]. Collected by: O. Breedy and H.M. Guzman, 29 April 2010.
DIAGNOSIS
Small, erect sea fans composed of 1–4 fronds. Stems short or absent, midribs not present, network irregular and open. Colonies white to pale pink, polyp mounds slightly raised and sparsely distributed. Coenenchymal sclerites mostly composed of long spindles reaching up to 0.25 mm in length. Anthocodial rods long and thin, up to 0.16 mm in length. All sclerites are colourless.
DESCRIPTION
The holotype consists of a fan-shaped colony, 11 cm in height, and 14.5 cm with two erect fronds that arise from a common, oval holdfast (17 mm in diameter) and extend in the same plane (Figures 1A, B). Stem is short, 3.5 mm in height, and slightly flattened, 2 mm in diameter. No midribs cross the fan. Network is irregular. Meshes are open (4–6 meshes/cm2), and mostly angular 2–13 mm long (Figure 1C). Mesh branches are squarish in cross-section, mostly 1–1.5 mm in diameter, but up to 2 mm in diameter at the base of the colony. End branchlets are 1–1.5 mm in diameter: they reach up to 19 mm long, and have blunt tips. Free twigs are scarce and reach up to 4 mm in length (Figure 1C). Colour of colony was white when alive and immediately after collection, but cream or pale pink when dry. Polyps are white and fully retractile into dome-shaped coenenchymal mounds which are slightly raised with slit-like apertures, up to 0.5 mm long (Figure 1C). Polyp-mounds are sparsely arranged, about 0.5–1.5 mm apart. Polyps are distributed mostly in two rows on each side of branches, or in a single row on thinner branches (Figure 1C). There are 22–28 per cm around a branch. Longitudinal grooves are slightly marked between the polyp rows along the branches. All sclerites are colourless. Anthocodiae are weakly armed with rods in untidy points-like arrangements. Anthocodial rods measure up to 0.14 mm in length and 0.02 mm in width and have margins that are scalloped or just have a few, short tubercles (Figure 3D). Coenenchymal sclerites are strongly tuberculated and are mostly long spindles with acute ends. They reach up to 0.23–0.25 mm in length, and 0.06 mm in width, with up to 12 complete whorls of warty tubercles, and constitute the longest spindles reported for the genus so far (Figure 2). A number of intermediate forms also occur in the coenenchyme: smaller irregular spindles with blunt warty ends, up to 0.10 mm in length and 0.05 mm in width (Figure 3A); small capstans and radiates, up to 0.065 mm by 0.035 mm (Figure 3B); and crosses that reach up to 0.065 mm by 0.06 mm (Figure 3C).
DESCRIPTION OF PARATYPES
Wider than high, STRI 1186 is 12.8 cm in height, and 13.1 cm in width, and STRI 1184 is 6.8 cm in height, and 7.7 cm in width. They agree in all essential aspects with holotype (Figure 1D). Anthocodials of the smallest colony reach up to 0.16 mm in length. Colonies white when alive or alcohol preserved and cream to pale pink when dry.
ETYMOLOGY
The species is named in honour of Erica Knie, founder and President of Fundación MarViva. Her love and passion for the oceans, unique philanthropic vision, and continuous support for law enforcement to protect marine resources in Latin America, particularly in Coiba National Park have inspired a regional change toward conservation.
HABITAT
This uncommon species was found at the base of a rocky pinnacle that breaks the surface from about 50 m deep. It was living together with other octocoral species, e.g. Pacifigorgia sculpta Breedy & Guzman, Reference Breedy and Guzman2004 and Eugorgia daniana Verrill, 1868 (typical form and an orange variety). Pacifigorgia marviva sp. nov. was the most abundant species (~12 individuals) at the collection site below 35 m and growing on flat rocky patch of approximately 250 m2 along a gentle slope to 50 m.
DISTRIBUTION
A survey of the entire west coast of Coiba and nearby high diversity rocky areas revealed that the species is presently recorded only from the type locality, Punta Hermosa, Coiba National Park, Pacific Panama.
DISCUSSION
The new species differs from other Pacifigorgia species especially in having the following combination of characters. First, the colonies are white or pale pink and the sclerites are all colourless, whereas Pacifigorgia is generally characterized by having bright coloured colonies—dull and whitish colours not being common. Second, long spindles with more than eight whorls of tubercles are the main component of the coenenchymal sclerites in this species, and they reach up to 0.25 mm in length, and third, colonies are composed of a few fans growing in the same plane, with open meshworks, and lacking distinct midribs crossing the fans. This new species has some similarity with Pacifigorgia senta Breedy & Guzman, Reference Breedy and Guzman2003a and P. sculpta. These two species also have large spindles in the coenenchyme and they can reach up to 0.22 mm, but these large sizes are not as abundant as they are in the coenenchyme of P. marviva sp. nov. (Table 1). Pacifigorgia senta has white colonies; however, the colonies have thinner branches, midribs, prominent polyp mounds and more open meshes than those of P. marviva (Table 1). Pacifigorgia sculpta also differs from the new species in the colour of the colonies (reddish brown) and sclerites (red-orange/pale-yellow), the meshes are larger, the polyp mounds are prominent, and the branches are thicker (Table 1).
Table 1. Comparative features of Pacifigorgia marviva sp. nov. and other related species.
Pacifigorgia sculpta is endemic, with a wide distribution in the Gulf of Chiriquí; P. senta has a wider geographical range of distribution, having been reported from Costa Rica and Baja California South (Mexico) (Breedy & Guzman, Reference Breedy and Guzman2003a). Pacifigorgia sculpta occurs together with P. marviva in the type locality, retaining their respective morphologies, also no intermediate forms were found in the collection site. Pacifigorgia senta has a deeper distribution range, down to 45 m. Its coexistence in the type locality has not been researched.
The genus Pacifigorgia has increased to 35 species along the eastern tropical Pacific region with this new addition (Breedy & Guzman, Reference Breedy and Guzman2002, Reference Breedy and Guzman2003a, Reference Breedy and Guzman2004; Williams & Breedy, Reference Williams and Breedy2004). Panama continues to have the most diversity of Pacifigorgia spp. in the region (sensu Guzman & Breedy, Reference Guzman and Breedy2008) with 20 species, representing 57% of the genus, followed by Costa Rica and Ecuador with 14 and 10 species, respectively. However, a preliminary similar high degree of endemism is observed in Panama, Costa Rica and Galápagos Islands (Ecuador) with five–six likely endemic species.
ACKNOWLEDGEMENTS
We are grateful to Phil Alderslade (CSIRO Marine and Atmospheric Research, Tasmania), Stephen Cairns (Museum of Natural History, Washington, DC), Leen van Ofwegen (Netherlands Centre for Biodiversity Naturalis, Leiden), and Sergio Vargas (Molecular Geo- and Palaeobiology, Geobiology and Palaeontology, LMU München) for critical review of the manuscript. We thank Percy Denyer (University of Costa Rica) for making the figures. This work was supported by the Secretaría Nacional de Ciencia y Tecnología of Panama (grant number PNCOIBA08-024) and the Smithsonian Tropical Research Institute.
