Gecko phylogeography in the Western Indian Ocean region: the oldest clade of Ebenavia inunguis lives on the youngest island

Hawlitschek O, Toussaint EFA, Gehring P-S, et al. Gecko phylogeography in the Western Indian Ocean region: the oldest clade of Ebenavia inunguis lives on the youngest island. JOURNAL OF BIOGEOGRAPHY. 2017;44(2):409-420.AimWe studied the gecko genus Ebenavia to reconstruct its colonization history, test for anthropogenic versus natural dispersal out of Madagascar, and correlate divergence date estimates of our phylogeny with geological age estimates of islands in the region. LocationMadagascar and surrounding islands of the Western Indian Ocean (Comoros, Mayotte, Mauritius, Pemba). MethodsWe reconstructed the phylogeny of Ebenavia covering its entire geographical range using a molecular data set of three mitochondrial and two nuclear markers. We estimated divergence times based on calibrations using (1) previously calculated mutation rates of mitochondrial markers, (2) a combination of these rates with old or (3) young geological age estimates for some of the islands inhabited by the genus, and (4) an independent data set with fossil outgroup calibration points. ResultsEbenavia inunguis, one of two recognized species of the genus, comprises multiple ancient evolutionary lineages. The earliest divergence within this complex (Miocene, 13-20Ma; 95% credibility interval [CI]: 4-29Ma) separates the population of the Comoros Islands, excluding Mayotte, from all other lineages. The age estimates for island lineages coincide with the geological age estimates of the islands except for Grand Comoro, where the age of the local clade (3-5Ma; 95% CI: 2-7Ma) significantly predates the estimated island age (05Ma). A clade from north Madagascar+Mayotte+Pemba is estimated to have diverged from an eastern Malagasy clade in the Miocene. Main ConclusionsOur results suggest that Grand Comoro Island is geologically older than previously estimated. The islands of the Comoros and Pemba were probably colonized via natural dispersal out of Madagascar (>1000km in the case of Pemba). Mauritius was most likely colonized only recently from eastern Madagascar via human translocation

Astylosternus occidentalis Parker 1931

Astylosternus occidentalis Parker, 1931 Figs. 3–7 Astylosternus occidentalis Parker, 1931, Ann. Mag. Nat. Hist., Ser. 10, 7: 492. Holotype: BMNH 1947.2. 5.48. Type locality: "Sandaru, E. Sierra Leone " collected on 24 June 1930 by G.L. Bates. Hylambates yalense Angel, 1944, Bull. Mus. Natl. Hist. Nat., Ser. 2, 16: 420. Holotype: MNHNP 1944.128; female, 64 mm. Type locality: French Upper Guinea, Yale; in secondary forest, Mont Nimba region, Guinea. Synonymy with Astylosternus diadematus by Guibé, 1950 " 1948 ", Cat. Types Amph. Mus. Natl. Hist. Nat.: 58. Synonymy with Astylosternus occidentalis by Lamotte, in Schiøtz, 1967, Spolia Zool. Mus. Haun., 25: 67. Astylosternus diadematus sensu Lamotte & Zuber-Vogel 1954, Bull. Inst. fond. Afr. noire, Sér. A, 16, 1222. Astylosternus occidentalis sensu Guibé & Lamotte 1958, Mém. Inst. fond. Afr. noire, 53, 261. Material studied. See Appendix 1. Re-description of the holotype [BMNH 1947.2.5.48; Fig. 3; measures in mm]. The adult male has a snoutvent length of 59.3 (63 according to original description; Parker 1931); snout rounded in dorsal view, obtuse in lateral view, longer than eye diameter; head width 22.3, head as long as broad; interorbital distance (8) narrower than length of upper eyelid; large protruding eyes, diameter 7.6; pupil vertically elliptic; tympanum large, distinct and vertically elliptic, diameter 4.5, 2 / 3 of eye diameter; distance eye-nose only slightly larger (5.3), than distance nose-snout tip (4.8), internarial distance 4.7; canthus rostralis distinct and curved, slightly bulging; loreal region concave; vomerine teeth in two short transverse rows between choanae; supratympanal fold distinct, bending from posterior corner of eyelid ventrad to a position in-between angle of mouth and forearm base; hypertrophied forearm; first finger 8.8, longer than second, 6.3; relative finger length: III>I>II≥IV; no digital webbing; femur length 23.7, shorter than tibia 28.2; foot with longest toe 36.8; finger and toe tips slightly broadened without forming discs; sub-articular tubercles very prominent; relative toe length: IV>III>V>II>I; distinct rudiments of webbing on toe bases; no skin fringes along toes; inner metatarsal tubercle (3.0) almost as long as shortest toe; outer metatarsal tubercle absent; skin on back “smooth” (very small spines present everywhere, only visible with higher magnification), i.e. no warts or ridges; paired vocal sac mediad to angle of mouth; vocal sac skin granular and coarsely folded; spines on lower mandible, arranged in 2–3 rows parallel to lower lip; spines conical with dark tip; large nuptial pads on thumb; scattered small spines along lateral edges of other fingers and beneath tympanum; conical spines on belly (dark in original description; possibly fainted); skin on outer part of thighs granular; skin on dorsal parts of body light brown, irregularly beset with small, roundish, dark brown spots; snout tip darker; light inter-ocular bar, posteriorly bordered by dark marking; iris uniform grey; lateral aspects of head beige, tympanum darker, upper lip with two dark bars; brown on flanks towards belly gradually fainting; limbs with indistinct brown transverse, partly interrupted bars; outer parts of thighs and sole of foot darker; ventral parts of skin yellowish white; vocal sac white like belly. Additional characters not assessed in holotype and variation. Mandible with single, small, tooth-like process in front of lower jaw, with socket in between pre-maxillae; upper pre-maxillae and maxillae with numerous teeth; vomerine teeth in form of two hemispherical odontophores, perpendicular to body axis, not in contact to each other medially, each odontophore with row of teeth like tips; distance from odontophores to elliptical choanae ranging from slightly larger to slightly smaller than maximum length of odontophores; choanae smaller than odontophores; tongue broadly heart shaped, deeply notched anteriorly, densely beset with small papillae, extends along entire length of lower jaw; posterior 2 / 3 of tongue free. Females are larger than males; otherwise measures and body ratios do not differ substantially between sexes (summarised in Tables 1 & 2). Males have external vocal sacs, which can be white to deep black; dark brown to black nuptial pads (see below), slightly hypertrophied forearms and skin along canthus rostralis more prominent, slightly swollen; the latter region in females much less distinct. Breeding males from Guinea with black spines in pectoral region (Fig. 5 b; not seen in males from Ivory Coast, Liberia and Sierra Leone; spines exhibiting same colour as rest of belly, but see above for holotype); spiny ventral area slightly converging towards and almost reaching vent; caudal half of ventral surface of shanks with honeycomb-like structure, in each comb a black roundish spine; respective surfaces of females smooth or slightly granular (caudad part of shanks). Whereas spines on breast and belly in breeding males (black nuptial pads on thumb) of all populations are almost always present, spines on shanks may be absent (ZMB 75469, 75468, both males with black nuptial pads on thumb and black spines on throat) or only weakly developed. Spiny pectoral area with loose black skin on otherwise white venter in males from western Guinea (Fig. 5 a), skin loosens or even disappears in preservation; in these males the throat along the lower mandible is almost black and males from Boffa have distinct spines in the angle of the mouth (less distinct or absent in others). No or traces of pedal webbing (Fig. 4 h). The dorsal colour varies significantly between and within populations (Fig. 6 a–p) and ranges from almost uniform coloured dorsal surfaces in grey, beige, yellow, orange, light and dark brown; to animals with regular or irregular dark spots on back; spots or bars on extremities; unmarked flanks and flanks with darker spots. A clear intraocular band is almost always visible, as is a dark barred upper lip. The most common colour patterns are shown in Fig. 6 a, b and d, respectively. Rarely animals with a chocolate brown back and an irregular pattern of reddish spots have been found (e.g. two females: ZMB 75375 from Loma mountains; ZMB 75361 from the Western Area Peninsula Forest Reserve, Fig. 6 i, both Sierra Leone). On Simandou we found one frog with olive spots on the back, the edges of these spots beset with black points (Fig. 6 h). ZMB 75473 shows an especially pronounced dotted back pattern, being light beige with black spots where the edges of spots are darker than their interior part. In contrast, ZMB 75479 (Fig. 6 e) is more or less greyish, exhibiting a “dirty” pattern without distinct black spots or dots. Animals from Ivory Coast, i.e. the region of Taï National Park, most often were yellow with small black points (Fig. 4 b). Whereas some specimens have distinct black bars on fore and hind limbs (Fig. 6 a, k, n); others have uniform (Fig. 6 c, d, f) or a mottled limb pattern (Fig. 6 g). The iris colour of all specimens was uniform grey. Throat and belly white to flesh coloured (exception some breeding males, see above), throats may be also speckled with dark brown patches, in some individuals (e.g. ZMB 75479) belly almost translucent; lower side of extremities grey to fleshy pinkish. Overall males seem to exhibit more often darker colours with less distinct pattern than females. These colour patterns all faint in preservation, usually resulting in specimens with beige to dark brown backs, black points and dots usually remaining discernible. The dorsal skin texture ranges from almost smooth (Fig. 6 e), to slightly granular (Fig. 6 g, i), irregularly best with longish flat warts (Fig. 6 f), to animals which exhibit a more or less smooth back skin and flanks with discontinuous longitudinal rows of narrow ridges (Fig. 6 a). We could not detect a consistent pattern of skin texture correlated with sex, age or season (e.g. breeding versus non-breeding animals). Advertisement call. Described by Schiøtz (1964 b) based on a specimen (ZMUC R 074932) from Kassewe, Sierra Leone. The call consists of two parts. The first part seems to be very similar to a call which we heard from Astylosternus from Mont Péko and which resembled the deep rattling call of some Ptychadena e.g. Ptychadena cf. schillukorum (Schiøtz, A. 1964 b as Abrana floweri; M.- O. Rödel, unpubl. data). The second, buzzing note was often heard alone, the first note was always followed by the second. Astylosternus occidentalis from Taï National Park, Ivory Coast, uttered a buzzing call only. Tadpole [description based on Lamotte & Zuber-Vogeli 1954 and tadpoles stored in MNHN and ZMB, see Appendix 1]. Exotrophic, lentic tadpoles; Gosner Stage 25– 35 larvae with: body elongate almost rectangular in dorsal, slightly ovoid in lateral view (Fig. 7 a), sides of body almost parallel; large lateral sacs originating posterior to eye run along flanks, less distinct in smaller than in large larvae; snout in dorsal view broadly rounded, a bit more pointed in lateral view; small eyes, positioned dorsolaterally; nares small, positioned dorsolaterally, closer to snout tip than to eyes; oral apparatus in anteroventral position; dorsal lip wide and smooth, with large anterior gap between marginal papillae; lateral papillae in multiple rows; ventral lip with large, uni- or biserial marginal papillae; upper jaw sheath massif, broad U-shaped, with strongly serrated margin; lower jaw sheath massif, V-shaped, margin strongly serrated; Stage 25 tadpoles and older have a labial tooth-row formula of 1: 2 + 2 / 2 + 2: 1 or 1: 1 + 1 / 2 + 2: 1; all keratodont rows on skin sheaths; kertodonts set very dense to each other; labial keratodonts unidenticulate, connected by hyaline skin reaching almost tips of keratodonts; vent tube dextral; spiracle sinistral; very long tail axis (approx. 2.5 times body length); tail axis height exceeds height of dorsal and most parts of ventral fin; dorsal fin originates slightly posterior to tail body junction; dorsal fin almost parallel to tail axis up to tail tip; ventral fin mostly narrower than tail axis, only in last third broader than tail axis; ventral fin almost parallel to tail axis; tail tip rounded; lines of pores (probably neuromast canals making up a side line system) starting on snout-tip; extending dorsally between eyes in two parallel rows to insertion of dorsal tail fin, below eyes dorsal from spiracle to about mid-body on flanks; pore rows circumventing eyes; visibility of pore rows better in younger stages; body more or less uniform dark brown to almost black, tail fin dark brown to almost black in last third of tail. The largest tadpole, Gosner Stage 37, measured 29.2 / 94.3 (body length/total length). Metamorphosing froglets (with rests of tail) measured 27.5–35.7 mm SVL (x ± sd: 32.3 ± 2.8; N = 10). Parker (1936) reported tadpoles collected in Liberia, the largest larvae with fully grown hind limbs measuring 88 mm (61 mm to the tail); a freshly metamorphosed froglet had a SVL of 30 mm. Lamotte & Zuber-Vogeli (1954) hint on the delayed appearance of the extremities, an adaptation to maintain, as long as possible, a good swimming performance in fast flowing habitats. Guibé & Lamotte (1958) mention tadpole sizes of close to 10 cm shortly before metamorphosis. Parker (1936) hints on the similarity of his tadpoles (body shape, proportions and dentition) with Angel’s (1930) description of Gampsosteonyx batesi (tadpoles from Foumban, Cameroon; thus most likely being tadpoles of A. diadematus). Natural history. Astylosternus occidentalis occurs along swift to fast-flowing creeks and streams in dense forest from almost sea level (130 m) to about 1300 m a.s.l. (Guibé & Lamotte 1958; Böhme 1994; this study). Its habitats may consist of primary as well as degraded or fragmented forests within the rainforest zone or dense gallery forest in the southern part of the humid Guinea savanna zone (Rödel & Branch 2002; Ernst & Rödel 2006; Ernst et al. 2006; Hillers & Rödel 2007; Hillers et al. 2008 a; this study). The species is usually not abundant and patchily distributed, similar to other anuran species associated with rivers in forests of hilly or mountainous areas (Lamotte 1966). In Mont Sangbé National Park individuals were observed within the forest in a steep valley (Rödel 2003). Whereas the vegetation on the valley ground and slopes consisted of rainforest trees, the hill tops carried savanna vegetation. One A. occidentalis male was found still within forest but only a few meters from true Guinea treesavanna (Rödel 2003). Similarly A. occidentalis has been recorded in gallery forest in the savanna zone of southeastern and western Guinea (this study). Guinean specimens in particular have been regularly encountered in some distance to water. Most populations, however, were recorded within forest close to flowing water. Males are calling from the forest floor close to but not in water (Schiøtz 1964 b). In contrast to Central African Astylosternus, we never observed West African frogs of the genus using the terminal phalanges of their hind feet in defence (see Blackburn et al. 2008). However, phalanges of western and central African Astylosternus species are anatomically indistinguishable (Barej et al. 2010). The reproduction behaviour is unknown. Tadpoles can usually be observed at night on the ground of slow or almost stagnant parts of forest creeks and rivers. Larger rivers as well as very small tributaries are inhabited. When disturbed tadpoles flee immediately into deeper and fast flowing water or burrow themselves into loose sediment of the shallow parts. Other anuran species which often occur in syntopy with A. occidentalis are Amietophrynus togoensis (Ahl, 1924), Cardioglossa occidentalis Blackburn, Kosuch, Schmitz, Burger, Wagner, Gonwouo, Hillers, & Rödel, 2008, Leptopelis macrotis Schiøtz, 1967, Phrynobatrachus liberiensis Barbour & Loveridge, 1927, Petropedetes natator Boulenger, 1905, Conraua spp., and Hyperolius chlorosteus (Boulenger, 1915). On Mont Péko, Ivory Coast (Fig. 8) the local Astylosternus, in particular their larvae, behaved differently. We collected two males and tadpoles (see taxonomic remarks) close to the summit at about 1000 m a.s.l. at the border of a heavily overgrown shallow creek (Rödel & Ernst 2003), flowing over massive granite underground. These males were calling at night, well concealed in small cavities under stones close to the creek’s bank. Several more males were heard but could not be exactly localised. The tadpoles were caught in shallow, slow flowing parts of the same creek and in very shallow ( 1000 m a.s.l.; coll. R. Ernst & M.- O. Rödel) appeared to differ from other A. occidentalis populations (compare Rödel & Ernst 2003). Their head width is in the range of the new species described below (Table 2), thus wider than in typical A. occidentalis. One male (SMNS 9615) was larger than any other Astylosternus from the western Upper Guinea forests (Fig. 1). They seemed to be more massive and had a smooth back skin (in life A. occidentalis granular skin, warts or ridges are usually discernible). For measures of both males see Tabs. 1 and 2. At the same locality we collected tadpoles (ZMB 77194, Fig. 7 b, c; same collection details as SMNS 9615 and 9616). The larval habitat was different to that of other known Astylosternus populations (see above). A species endemic to the Mont Péko region in Ivory Coast would be in line with recent findings in other frog genera of similar ecological requirements (Conraua and Petropedetes; M.F. Barej & M.- O. Rödel unpubl. data). However, given the range of variation within the various A. occidentalis populations, further vouchers and genetic samples are needed to clarify the taxonomic status of the Mont Péko frogs. Conservation status. Given the rather wide distribution of the species, including various protected areas (i.e. Taï National Park, Sapo National Park, Mount Nimba Biosphere Reserve) and its apparent potential to survive in altered forest habitats, the current IUCN RedList classification of “Least Concern” should be kept. If new findings would proof the Mont Péko frogs being a separate species; this taxon would be highly threatened due to a restricted range of occurrence and very intense pressure of logging and other anthropogenic activities.Published as part of Rödel, Mark-Oliver, Barej, Michael F., Hillers, Annika, Leaché, Adam D., Kouamé, N'Goran G, Ofori-Boateng, Caleb, Assemian, Emmanuel, Tohé, Blayda, Penner, Johannes, Hirschfeld, Mareike, Doumbia, Joseph, Gonwouo, Legrand Nono, Nopper, Joachim, Brede, Christian, Diaz, Raul, Fujita, Matthew K., Gil, Marlon & H, Gabriel, 2012, The genus Astylosternus in the Upper Guinea rainforests, West Africa, with the description of a new species (Amphibia: Anura: Arthroleptidae), pp. 1-29 in Zootaxa 3245 on pages 9-16, DOI: 10.5281/zenodo.28050

Life in the spray zone - overlooked diversity in West African torrent-frogs (Anura, Odontobatrachidae, Odontobatrachus)

West African torrent-frogs of the genus Odontobatrachus currently belong to a single species: Odontobatrachus natator (Boulenger, 1905). Recently, molecular results and biogeographic separation led to the recognition of five Operational Taxonomic Units (OTUs) thus identifying a species-complex. Based on these insights, morphological analyses on more than 150 adult specimens, covering the entire distribution of the family and all OTUs, were carried out. Despite strong morphological congruence, combinations of morphological characters made the differentiation of OTUs successful and allowed the recognition of five distinct species: Odontobatrachus natator, and four species new to science: Odontobatrachus arndti sp. n., O. fouta sp. n., O. smithi sp. n. and O. ziama sp. n. All species occur in parapatry: Odontobatrachus natator is known from western Guinea to eastern Liberia, O. ziama sp. n. from eastern Guinea, O. smithi sp. n. and O. fouta sp. n. from western Guinea, O. arndti sp. n. from the border triangle Guinea-Liberia-Cote d'Ivoire. In addition, for the first time the advertisement call of a West African torrent-frog (O. arndti sp. n.) is described

Astylosternus laticephalus Rödel, Barej, Hillers, Leaché, Kouamé, Ofori-Boateng, Assemian, Tohé, Penner, Hirschfeld, Doumbia, Gonwouo, Nopper, Brede, Diaz, Fujita, Gil & H, 2012, sp. nov.

Astylosternus laticephalus sp. nov. Rödel, Hillers, Leaché, Kouamé, Ofori-Boateng, Diaz & Sandberger Figs. 9–12 Holotype. ZMB 75449 (field and tissue #: ATE 10, female, 58.6 mm), Ghana, Atewa Forest Reserve, 6.23375 / - 0.56557, 14 April 2007, forest around stream next to road, coll. C. Ofori-Boateng, A. Hillers & G. Segniagbeto. Paratypes. Ivory Coast: MTD 48026 (field and tissue #: Ba04.24, female, 62.2 mm), ZMB 75454 -75458 (Ba04.26, subadult, 45.5 mm; Ba04.25, female, 62.5 mm; Ba04.21, female, 64.4 mm; Ba04.22, subadult, 43.3 mm; Ba04.23, female, 58.4 mm;), Banco National Park, 5.41667 / -4.10500, rainy season 2004, swampy forest, coll. N.E. Assemian, B. Tohé & G. Kouamé; MNHN 1993.6073 (male, 53.8 mm), 1999.7333 (female, 54.8 mm), 1999.7334 (male, 48.7 mm), 1999.7335 (female, 59.8 mm), 1999.7736 (female, 52.6 mm), 1999.7337 (female, 51.8 mm), Banco National Park, Abidjan; Ghana: ZMB 75459 (AF 4, juvenile, 25.6 mm), ZMB 75459 -75460 (AF 3 juvenile; 26.7 mm; AF 2, tadpole), Afao Hills Forest Reserve, 6.25461 / - 2.29492, riparian forest around small stream in valley, coll. C. Ofori-Boateng & A. Hillers; ZMB 75450 -75453 (COB 90, juvenile, 34.7 mm; COB 318, subadult, 40.8 mm; COB 119, juvenile, 38.6 mm; COB 123, juvenile, 31.7 mm), Western Province, Ankasa Conservation Area, pristine forest along streams in dry season, coll. C. Ofori-Boateng; MVZ 244910 (female, 67 mm), Ankasa Conservation Area, 5.28173 / - 2.64022, 26 June 2004, wet evergreen forest area, trail adjacent to the bamboo cathedral, coll. A.D. Leaché & R. Diaz; MVZ 244909 (juvenile, 35 mm), 28 June 2004, approximately 1 km farther from the bamboo cathedral, other data as MVZ 244909. Additional material. ZMB 77461 (field# AF 03), tadpole, Ghana, Afao Hills Forest Reserve, 6.25461 / - 2.29492, riparian forest around small stream in valley, coll. C. Ofori-Boateng & A. Hillers; ATE 7 (tissue only), juvenile, 25.8 mm; ATE 8 (tissue only), juvenile, 28.6 mm; ATE 27 (tissue only), male, 45.6 mm, Ghana, Atewa Forest Reserve, 6.23375 / - 0.56557, 15 April 2007, swampy area next to small stream, in valley in forest, coll. C. Ofori-Boateng, A. Hillers & G. Segniagbeto; COB 2202 (collection Ofori-Boateng, Kumasi, Ghana), Ghana, Atewa Forest Reserve, coll. C. Ofori-Boateng; three adult specimens without number (amphibian reference collection at University Abobo-Adjamé, Ivory Coast), male (51.0 mm), females (60.0, 67.0 mm), Ivory Coast, Banco National Park, 5.41667 / -4.10500, 5 May 2004, forest close to Banco River, coll. N.E. Assemian, N.G. Kouamé & B. Tohé. Diagnosis. Astylosternus laticephalus sp. nov. has the typical body shape of frogs of the genus Astylosternus, however, with exceptionally broad heads, i.e. broader than in A. occidentalis; males of the new species without spines on throat and belly (always present in A. occidentalis males); males without nuptial black skin layer in pectoral region (present in male A. occidentalis from western Guinea); back brownish to brownish red, always with distinct red dots (red dots only rarely present in A. occidentalis); bicoloured iris, grey with a reddish upper third (A. occidentalis always with uniform grey iris). A. laticephalus sp. nov. differs from A. occidentalis by a mean of 3.2 % (range 2.9-3.7 %) in the investigated part of the 16 S rRNA gene. Genetic divergence to the morphologically most similar Central African species, A. diadematus, was 11.9 %. Description of the holotype [measures in mm]. The holotype is an adult female with a snout-vent length of 58.6; head width 22.7; head as long as broad; interorbital distance narrower than length of upper eyelid; snout rounded in dorsal view, obtuse in lateral view, longer than eye diameter; eyes large (7.9) and protuberant directed anterolaterally; interorbital distance 7.2; pupil vertically elliptical; eye diameter larger than tympanum diameter, 5.3; tympanum vertically elliptical; supratympanal fold from posterior vertical midpoint of orbit to meet with dorsal border of tympanic annulus, where descent is sharp and terminates at half the vertical diameter of the tympanic annulus dorsally to the axilla; nares closer to snout-tip (2.7) than to eye (5.5), nostrils oriented posterolaterally; internarial distance 4.4; canthus rostralis rounded and straight; loreal region slightly concave and gradually sloping laterally; single, small, tooth-like process at lower jaw symphysis, with corresponding socket in between premaxillae; upper premaxillae and maxillae with numerous teeth; vomerine teeth in form of two hemispherical odontophores, perpendicular to body axis, almost being in contact to each other medially, each with row of teeth like tips (5 left, 6 right); distance from odontophores to elliptical choanae slightly larger than maximum length of odontophores; choanae almost equal in size to odontophores; tongue broadly heart shaped, deeply notched anteriorly, densely beset with small papillae, extends over entire length of lower jaw; posterior 2 / 3 of tongue free. Forelimbs robust, fingers slender and long; prepollex absent; first finger 10.3, almost double the length of second finger (5.1); relative finger lengths I>III>II>IV; finger tips broadened without forming discs; subarticular tubercles large, subconical, protruding distally; thenar and palmar tubercles large and elliptical; supernumerary tubercles absent; number of subarticular tubercles on digits I-IV: 1, 1, 2, 2; no digital webbing; hind limbs short and robust; femur length 28.3, almost equal to tibia 28.4; tibia-fibula with longest toe 38.4; relative toe lengths IV>III>V>II>I; shortest toe (4.2) almost double the length of inner metatarsal tubercle (2.3); inner metatarsal tubercle large, elliptical; toe tips broadened without forming discs; number of subconical subarticular tubercles on toes I-V: 1, 1, 2, 3, 2; supernumerary tubercles absent; traces of webbing between toe bases; no skin fringes along toes. Tip of toe IV on left foot missing. Skin on head, back, belly and throat predominantly smooth; small whitish spines scattered on back, dorsal parts of extremities and eyelids; white warts posterior to angle of mouth, ventral from tympanum; posterior region of thighs areolate; irregularly spread narrow low tubercles along flanks; no tubercles or warts on forearms or interocular region; head with white scratches (scars). Base colour of dorsum in preservation is a light brown to reddish brown; back with irregularly arranged and shaped light beige spots; upper eyelids greyish; head laterally with two darker bars, the posterior one below eye; upper and lower lips white; supratympanic fold anteriorly rimmed thin black; warts on flanks beige; forelimbs dorsally light brown, slightly mottled beige, first two fingers almost uniform white; hind limb colour as forelimbs, dark bordered cross bars indicated in thighs (4) and lower legs (5-6); throat, belly, ventral parts of fore- and hind limbs uniform white or creamish; only ventral part of feet reddish brown, metatarsal tubercle and subarticular tubercles creamish white. Variation. Females seem to be larger (up to 67.0 mm; MVZ 244910) than males (53.8 mm), although the small sample size of the latter (N = 2) does not allow for generalization. The tympanum shape varies between vertically elliptical (most vouchers) to round; the supratympanic fold is sometimes thin to absent; sometimes tympanic membrane prominent within faint tympanic annulus. Other measures and indices identical between the two sexes; values are summarized in Tabs. 1 and 2. Dorsal and lateral skin texture can consist of many irregularly spaced small roundish warts, not arranged in rows, sometimes fused to small ridge like structures (Fig. 11). Males have paired subgular vocal sacs, visible in preserved frogs as slightly loose, granular black skin near the angles of the mouth; males with large brown nuptial pads on the external side of the thumb. Canthus rostralis in males more prominent bulging and rounded; males with more massive forearms than females. In contrast to other western West African Astylosternus, A. laticephalus sp. nov. males in breeding condition, lack spines on throat and belly. The dorsal base colouration in life consists of a light grey, brown, reddish brown or almost black; all specimens exhibit a more or less dense pattern of smaller to larger, irregularly shaped red spots on back; smaller black or brown spots may be present, in particular in juveniles; iris greyish, upper third reddish to orange; the anterior part of the eyelids bright yellow to red blotches, connected by a very conspicuous interorbital stripe of the same colour; snout tip and area posterior to interorbital stripe, including posterior part of eyelid, darker than rest of back, this pattern sometimes consisting of a symmetrical pair of triangular shaped black spots (Fig. 11); frenal area dark as snout tip; loreal area distinctly lighter coloured than snout tip; light infraorbital batch; supratympanal ridge usually bordered by thin black line; fore and hind limbs with or without distinct black cross bars; lateral colour gradually fainting from back colour to whitish venter, with irregularly scattered black points; ventral coloration (throat and abdomen) creamish-white; ventral surface of thighs and arms creamish-yellow with reddish brown mottling around lateral margins of limbs. In preservative all patterns and coloration almost as in life, but faded; the red dorsal spots remain as light beige spots. Tadpole [measures in mm; description based on ZMB 75460]. Exotrophic, lentic tadpole; Gosner stage 39; total length 62.1; body broad almost as long as wide, slightly elliptical in dorsal, slightly depressed in lateral view (possibly a preservation artefact); body length 23.8; body width 24.2; sides of body slightly concave, snout in dorsal view broadly rounded, a bit more pointed in lateral view; large lateral sacs originating posterior to eyes run along flanks; small eyes, positioned dorsolaterally, pupil round; nares small, positioned dorsolaterally, closer to snout trip than to eyes; oral apparatus in anteroventral position; dorsal lip wide and smooth, with large anterior gap between marginal papillae; lateral papillae ventral lip with large, uni- or biserial marginal papillae; upper jaw sheath massif, broad U-shaped, strongly serrated margin, most central “tooth” most prominent; lower jaw sheath massif, V-shaped, margin strongly serrated; labial tooth-row formula 1: 1 + 1 / 3; all keratodont rows on skin sheaths; labial keratodonts unidenticulate, connected by a hyaline skin; vent tube dextral; spiracle sinistral (almost invisible); very long tail axis (> 2.5 times body length); tail axis height largely exceeding height of dorsal and ventral fin, both fins very narrow; dorsal fin originates slightly posterior to tail body junction; dorsal fin almost parallel to tail axis up to rounded tip; no pores (neuromast canals) visible (possibly due to poor preservation or advanced developmental stage); body more or less beige, mottled with dark brown, tail fin brown to almost black in last third of tail. Newly metamorphosed froglets measured 25.6–28.7 mm (N = 2). Natural history. Not much is known about the biology of the new species. Astylosternus laticephalus sp. nov. lives in lowland rainforest habitats (Fig. 13), mostly close to small or mid sized streams (Rödel et al. 2005; Assemian et al. 2006). In Banco National Park, Ivory Coast we recorded the new species in the leaf litter of swampy areas in closed canopy forest, open forest and in natural forest gaps, both in close vicinity to the River Banco and in larger distance (about 1 km) from the river (Assemian et al. 2006). A total of 12 specimens were only observed during the rainy season, 11 of them during the night. In the Ankasa Conservation Area we found the new species in wet evergreen forest on a trail adjacent to the Bamboo Cathedral (Fig. 13 b). Distribution. So far A. laticephalus sp. nov. is known from one forest in eastern Ivory Coast, the Banco National Park (Assemian et al. 2006), and various sites in Ghana: Afao Hills Forest Reserve, Draw River Forest Reserve and Ankasa Conservation Area in south-western Ghana (Rödel et al. 2005; this paper), and Atewa Range in southern-central Ghana (Fig. 8). The latter site was chosen as type locality of the new taxon to underline the outstanding importance of this mountainous region for the Ghanaian biodiversity. Conservation status. The distribution of the species from eastern Ivory Coast to southern-central Ghana, including various protected areas (i.e. Banco National Park, Afao Hills Forest Reserve, Ankasa Conservation Area), seems to imply a IUCN RedList classification of “Least Concern”. However, rainforests in south-eastern Ivory Coast are under intense logging pressure and highly fragmented. Forests in south-western Ghana are better protected but likewise fragmented and the Atewa Range is currently under threat because of small scale mining activities and further plans to mine for gold, diamonds and bauxite on an industrial scale. We thus suggest classifying the new species as “Near Threatened”. Etymology. The name derives from the Latin words latus for wide and the Greek Kεφάλɩ for head, referring to the conspicuous wide head of the new species.Published as part of Rödel, Mark-Oliver, Barej, Michael F., Hillers, Annika, Leaché, Adam D., Kouamé, N'Goran G, Ofori-Boateng, Caleb, Assemian, Emmanuel, Tohé, Blayda, Penner, Johannes, Hirschfeld, Mareike, Doumbia, Joseph, Gonwouo, Legrand Nono, Nopper, Joachim, Brede, Christian, Diaz, Raul, Fujita, Matthew K., Gil, Marlon & H, Gabriel, 2012, The genus Astylosternus in the Upper Guinea rainforests, West Africa, with the description of a new species (Amphibia: Anura: Arthroleptidae), pp. 1-29 in Zootaxa 3245 on pages 16-22, DOI: 10.5281/zenodo.28050