Morerella cyanophthalma Rödel, Kosuch, Grafe, Boistel, Assemian, Kouamé, Tohé, Gourène, Perret, Henle, Tafforeau & Pollet, 2009, sp. nov.
Creators: name: Rödel, Mark-Oliver
name: Kosuch, Joachim
name: Grafe, Ulmar
name: Boistel, Renaud
name: Assemian, Emmanuel
name: Kouamé, N'Goran G.
name: Tohé, Blayda
name: Gourène, Germain
name: Perret, Jean-Luc
name: Henle, Klaus
name: Tafforeau, Paul
name: Pollet, Nicolas
Publisher: name: Zenodo
Year: 2009
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Amphibia
Anura
Hyperoliidae
Morerella
Morerella cyanophthalma

description: Morerella cyanophthalma sp. nov. Rödel, Assemian, Kouamé, Tohé & Perret
Figs 1–8
Holotype. MHNG 2131.44, adult male, Banco National Park, N 05°25', W 04°03', Ivory Coast, 1980, coll. Jean-Luc Perret.
Paratypes. MHNG 2131.36-43, 45-55, 17 adult males, two adult females, other data as holotype; SMNS 11939 adult male, Banco National Park, near forest school, N 05°23’.104’’, W 04°03.072’’, Ivory Coast, 4 September 2003, coll. N.E. Assemian, N.G. Kouamé, B. Tohé & M.-O. Rödel; SMNS 11940, adult male, stained and cleared, other data as SMNS 11939; ZFMK 82796, adult male, same data as SMNS 11939; ZMB 71565 (GenBank accession numbers: 16S: FJ594100; 12S: FJ594106; Cytb: FJ594111), adult male, same data as SMNS 11939; ZMB 71566, adult male, stained and cleared, same data as SMNS 11939; ZMB 71588- 71590, 73271, four adult males, Banco National Park, swampy forest with shallow puddles near river and open area near fish culture ponds, N 05°25’, W 04°03’, Ivory Coast, 23 September 2004, coll. N.E. Assemian, N.G. Kouamé, B. Tohé & M.-O. Rödel.
Additional material. ZMB 71591, 23 tadpoles (Gosner stage 23–41) and six metamorphs from captive breeding (parents from type locality); ZFMK 42351-42355, 42390, two males, four females, wet primary rainforest, Azagny National Park, Ivory Coast, 22 February to 9 May 1984, coll. K. Henle.
Description of the holotype (measurements in mm). The holotype is an adult male in reproductive status. Slender body (SUL 30.1); comparatively flat head; slightly pointed snout; head width (9.7) approaches one third of SUL; inter-orbital-distance (3.8) equals diameter of large and protruding eyes (4.0); pupil horizontal oval; tympanum small (1.3) but distinct, reaches only about one third of eye diameter; internarial-distance is 2.4; naris much closer to snout tip (0.6) than to eye (2.7); loreal region very slightly convex; canthus rostralis present and rounded; large granular gular gland (7.8 x 6.5) stretching from middle of the throat onto anterior part of breast (Fig. 1); no dilatable skin beneath or around gular gland; upper mandible with minute teeth; prevomerine teeth absent; tongue heart shaped, slightly notched posteriorly, more than two thirds free; dorsal surfaces with minute spines, largest spines densely on lower and outer part of hind feet; ventral surfaces granular; femur length (14.3) and tibia length (15.7) reach about half SUL; foot incl. longest toe (21.2) reaches about two thirds of SUL; finger and toe tips enlarged to round discs; finger formula: 1<2<4<3; only traces of webbing between fingers; one subarticular tubercle on fingers 1, 2 and 3, 2 subarticular tubercles on finger 3; small plamar tubercle (Fig. 2); toe formula: 1<2<3=5>4; toe 2, 3 and 5 with two subarticular tubercles, toe one with one tubercle, toe 4 with three tubercles; small elongate inner metatarsal tubercle; lower side of feet densely beset with flattened tubercles; webbing formula: 1 (1), 2 i /e (1-0.5), 3 i /e (1-0.5), 4 i /e (1), 5
Color of holotype in preservative. Dorsal surfaces dark reddish brown with irregular black spots on back, lower arm and lower leg; thighs dorsally uniform red brown; dark canthal stripes; lips whitish with brown spots; throat with brownish spots; gular gland yellowish beige; flanks clear brown dorsally, almost white ventrally; belly whitish; toe and finger tips slightly darker than rest of hand and feet; lower side of feet grey; lower parts of thighs uniform pinkish brown in anterior half, posterior half with many darker spots, ventral part of lower leg uniform pinkish.
Variation. Morphologically the type series is similar to the holotype. Both sexes may reach a maximum SUL of 34–35 mm. However, adult males were significantly smaller than adult females (Mann-Whitney- U test, Z = -3.515, p = <0.001; N= 88). Morphological measures are summarized in Tab. 4. Females lack the gular gland and spines. In live animals dorsal and ventral skin surfaces of both sexes were always granular. In preservation dorsal skin appears smooth in most males. In contrast female skin is still granular. The gular gland is already present in male frogs exceeding 23 mm SUL. Gland size varies considerably (Fig. 1) but generally increases with body size (Spearman rank correlation between SUL and gular gland surface, r s = 0.518, p = 0.016, N= 21). While calling the gland is slightly bulged to a small semisphere, also comprising the anterior part of the breast.
males females
Although M. cyanophthalma sp. nov. is morphologically invariable, the colour pattern varies (Fig. 3). The sexes are dichromatic. The females have a uniform brownish red, red-beige or bright orange-red dorsum, including extremities and toe and finger discs. Their throat and belly is colored whitish yellow to orange, the ventral parts of hind limbs are bright yellow or orange. The iris of females is grayish blue to bright blue. The iris of males varies from porcelain white in bright sunlight to grayish or yellowish brown in darker surroundings. Male dorsal surfaces including extremities vary between dark brown or almost black, to clear beige. Males’ backs can be either uniform or covered with smaller blackish and/or yellowish spots. In daytime retreats some males change to almost female orange coloration. At night the basic color of males changes to a clear yellow. Males almost always have dark canthal stripes (not visible in very dark individuals), that sometimes is bordered dorsally by a narrow yellowish stripe. The latter often continues behind the eyes as a dorsolateral band, which however, almost always breaks into spots and vanishes just dorsal to the forearm origin. Males’ throats and gular glands are whitish yellow to yellow. The bellies are white, rarely yellow, the lower surfaces of hind limbs are dark grey, in rare cases orange like in females. Breasts and the ventral parts of males’ forearms are flesh-colored, possibly indicating pectoral and humeral glands. Toe and finger tips exhibit the coloration of the back or are grey. In preservation most males are identical to the holotype. Dorsolateral bands remain visible in preservation, few males have almost uniform brown backs. Females in preservation are uniform brown dorsally and uniform clear pinkish ventrally or almost uniform clear beige with minute small black points.
Osteology. Skull slightly longer than broad; snout rounded in dorsal and ventral view (Fig. 4); surfaces of skull almost smooth; nasals triangular, not in contact with each other, canthal area rounded; sphenethmoid not visible dorsally; ventroanterior portion of sphenethmoid unfused, consisting of two elements; frontoparietal large and rectangular; quadratojugal narrow, contacts maxilla anteriorly; maxilla and premaxilla with minute teeth, prevomerine teeth absent; columella present; thyrohyal bones on cartilaginous stalks; posterolateral process of hyoid absent; anteriormost portion of the anterior horn of hyoid absent, hence horn composed of an anteromedial and a lateral process (staining and microtomography revealed slight differences in the shape of the lateral element of the anterior horn; Fig. 5); vertebrae diplasiocoelous; neural arches non-imbricate, not completely roofing the spinal canal; transverse processes of eighth vertebra not angled markedly forward (Fig. 6); pectoral girdle firmisternal; medial margins of coracoids entire; omosternum greatly forked, space between arms more than twice width of one arm; sternum ratio of caudal margin to anterior margin is 2.3; sternum completely ossified (microtomography results showed a more compressed sternum compared to staining and clearing, Fig. 6 a & b); terminal phalanges slender, slightly curved and peniform; intercalary elements between ultimate and penultimate phalanges of fingers and toes present and completely mineralized (Fig. 2).
Vocalization. The advertisement call was a tonal note typically repeated 2–3 times (Fig. 7). Calls were short in duration (83 ± 7 ms, range 76–90 ms, N= 3). Intervals between calls within a call group averaged 174 ± 8 ms (range = 122–236 ms, N= 3). Dominant frequency of calls was 2.40 ± 0.02 kHz (range = 2.38–2.41 kHz, N= 3).
Tadpole description. Exotrophic, lentic tadpoles; Gosner stage 25– 28 larvae with: body elongate ovoid in dorsal, slightly depressed in lateral view (Fig. 8), sides of body almost parallel; small eyes, positioned dorsolaterally; nares large, positioned dorsally, approximately equal distance to eyes and snout-tip; oral apparatus in anteroventral position; dorsal lip wide and smooth, with anterior gap of marginal papillae; ventral lip with large, biserial marginal papillae; submarginal papillae absent; upper jaw sheath is a narrow smooth arc; lower jaw sheath u-shaped; labial tooth row formula in young stages just after hatching: 0/0; stage 25 tadpoles and older have a labial tooth row formula of 1/1+1:2; supra-angular labial teeth row on bulging lip; infra-angular labial teeth rows on separate dermal lobes (Fig. 8); few labial teeth unidenticulate (most on upper lip); most labial teeth multidenticulate (Fig. 8); vent tube dextral; spiracle sinistral; very long tail axis (> 2 times body length); tail axis height almost equals height of dorsal fin; dorsal fin originates dorsal to tail body junction, highest point is anterior to mid point of tail; ventral fin narrower than tail axis, almost parallel to tail axis; tail tip rounded. Body clear brownish dorsally, a band stretching between eyes from tail body junction anteriorly to level of nares slightly clearer brown, bordered by reddish brown line, lateral and ventral body parts almost translucent; three pairs of silverish spots caudal to eyes, converging towards mid body; tail axis cream with a narrow dorsal brown stripe, tail fins hyaline.
Freshly hatched tadpoles have very large yolk sacs; a body length of 2.3 mm and a total length of 5.6 mm. Shortly before metamorphosis (Gosner stages 37–41) tadpoles reach body lengths of 10.18–11.78 mm (x = 11.12 mm ± 0.67 sd; N= 4) and total lengths of 37.37–40.73 mm (x = 38.55 mm ± 1.58 sd; N= 4). Snouturostyle length of froglets with four limbs and no or only short tails ranged from 9.75–13.31 mm (x = 11.45 mm ± 1.14 sd; N= 6).
Natural history. The type locality of M. cyanophthalma sp. nov. is a water filled rill (1 m width, about 50 cm deep; clear; slow-flowing water; submerged vegetation) that is situated between a clearing and swampy rainforest (1–5 m apart; see Fig. 7 in Assemian et al. 2006). On 4 September 2003 we recorded about 15 males and one female (16–21 hours; 25 man-hours), all calling from the forest side of the rill. The type locality is situated in the centre of Banco National Park. This area consists of the Banco River, very swampy forest and a large clearing with many stagnant pools that are used to breed Tilapia species. M. cyanophthalma sp. nov. was also recorded from a few other forest sites in Banco National Park, however, all close to the type locality. Other frog species recorded near the type locality (forest and clearing) were: Amietophrynus maculatus (Hallowell, 1854), Amietophrynus regularis (Reuss, 1833), Hoplobatrachus occipitalis (Günther, 1858), Aubria subsigillata (Duméril, 1856), Hylarana albolabris (Hallowell, 1856), Ptychadena mascareniensis (Duméril & Bibron, 1841), Phrynobatrachus ghanensis Schiøtz, 1964, P. liberiensis Barbour & Loveridge, 1927, Arthroleptis spp., Leptopelis spiritusnoctis Rödel, 2007, Afrixalus dorsalis (Peters, 1875), Hyperolius concolor (Hallowell, 1844), H. picturatus Peters, 1875, H. guttulatus Günther, 1858, H. fusciventris lamtoensis Schiøtz, 1967.
M. cyanophthalma sp. nov. is a nocturnal tree-frog, becoming active when darkness falls (18:00–19:00 hours). Calling peaked in the field between 20:00 and 21:00 hours. After 01:00 hours in the morning, calls are uttered only very rarely. Males and females sit at heights of 0.4–1.8 m on leaves of herbs and shrubs in swampy areas close to creeks and rivers. During daytime they sometimes hide in the leaf litter, but usually between leaves of herbs and shrubs. In the lab (12/12 light cycle) the frogs spend the day well hidden in leaf axils. Calling activity started later than in the field, sometimes not before midnight. On very hot and humid days, males also called during daytime. We only once discovered a clutch deposited shortly after noon. Most clutches seemed to have been deposited at night. Eggs were usually attached in groups to the dorsal surface of leaves or roots, mostly 2–15 cm above water (N> 10). In a few cases we found eggs attached to a root just below water surface (N= 2) or in the water (N= 2). Eggs that were covered with water did not develop. We often observed frogs sitting on the lower side of leaves just above the clutches, but we are uncertain whether this constitutes parental care. Egg numbers ranged from 30– 144 eggs (x= 73.8 ± 39.3 sd; N= 8). The mean germ size of the black and white eggs was 1.53 mm (± 0.08 mm sd; N= 9). Mean size of the eggs with jelly was 4.69 mm (± 1.00 mm sd; N= 9). Tadpoles hatched after 8–10 days with a large, bulging yolk sac, external gills, mouth still closed. One day after hatching tadpoles were free swimming. The mouth of eight day old tadpoles started opening; upper and lower jaw sheets became visible as narrow arches. The tadpoles still had external gills. Tadpoles lost the external gills after eleven days when they started feeding. Further development in captivity was very slow and most tadpoles died of unknown reasons. Embryos only developed and hatched successfully in slightly acid water (pH 6–6.5) and very low conductivity. In captivity we recorded the first clutch on 11 May 2004 (egg count not possible). The same female deposited further clutches on 17 June (59 eggs) and 23 July 2004 (97 eggs), respectively. On 9 October 2006 the first F 1 female deposited a clutch of more than 100 eggs. Developmental time under natural conditions is unknown.
The Morerella specimens from Azagny National Park were collected in wet to swampy primary forest with comparatively low canopy (18 m) and Raphia palms. They were sitting in low heights, but always above 1.5 m. These places where often above water or floating herbs. Their morphology clearly characterizes them as members of the new genus. Future research is needed to discern if this population is conspecific with M. cyanophthalma or if they represent another new species of this genus.
Distribution. So far the new species is known from a few sites within Banco National Park, Ivory Coast. Additional frogs possibly conspecific with the new species have been recorded by us (K. Henle) in the Azagny National Park, 100 km west of Abidjan (see non-type material). K.E. Linsenmair (pers. comm.) took a picture of a morphologically similar looking frog (although completely yellow) in southern Taï National Park, 350 km from the type locality.
Etymology. The species name is based on the Greek and refers to the bright blue [blue = cyano] color of the females’ eyes [eye = ophthalmos].
Conservation status. According to the IUCN Red List categories and criteria M. cyanophthalma sp. nov. is Critically Endangered (Baillie et al. 2004). This categorization is based on the fact that the extent of occurrence is less than 100 km ² and the area of occupancy is less than 10 km ². A population decline, by habitat loss and/or reduced habitat quality, can be inferred by the close proximity to Abidjan. If the records from Azagny and/or Taï National Park would be conspecific with M. cyanophthalma sp. nov., the species’ status should be changed to Endangered or Vulnerable, respectively.
description: Published as part of Rödel, Mark-Oliver, Kosuch, Joachim, Grafe, Ulmar, Boistel, Renaud, Assemian, Emmanuel, Kouamé, N'Goran G., Tohé, Blayda, Gourène, Germain, Perret, Jean-Luc, Henle, Klaus, Tafforeau, Paul & Pollet, Nicolas, 2009, A new tree-frog genus and species from Ivory Coast, West Africa (Amphibia: Anura: Hyperoliidae), pp. 23-45 in Zootaxa 2044 on pages 29-37, DOI: 10.5281/zenodo.186394