Hyalinobatrachium kawense, Castroviejo-Fisher, Santiago, Vilà, Carles, Ayarzagüena, José, Blanc, Michel & Ernst, Raffael, 2011

Castroviejo-Fisher, Santiago, Vilà, Carles, Ayarzagüena, José, Blanc, Michel & Ernst, Raffael, 2011, Species diversity of Hyalinobatrachium glassfrogs (Amphibia: Centrolenidae) from the Guiana Shield, with the description of two new species, Zootaxa 3132, pp. 1-55 : 23-26

Hyalinobatrachium kawense sp. nov.

( Fig. 7 )

Hyalinobatrachium aff. mondolfii Guayasamin et al., 2008a: 580 .

Holotype. MNCN 44825 (field code MB 241), adult male from Rivière de Kaw (04°36'33'' N, 52°03'25'' W; 1–10 m), French Guiana, collected by M. Blanc on February 0 6, 2005.

Paratopotypes. MNCN 44825 (field code MB 252), MNHN 2011.0118 (field code MB 253), MNHN 2011.0119 (field code MB 254), adult males and MTD 48143 (field code MB 259), adult female collected by M. Blanc on April 15 (males) and 16 (female), 2005.

Paratypes. MTD 48142 (field code MB 255), adult male from Canal de Kaw (04°30' N, 52°1' W; 1 m) collected by M. Blanc on April 17, 2005; MTD 48144 (field code MB 260), adult male from Crique Gabrielle (04°41' N, 52°18' W; 2–10 m), collected by M. Blanc on May 0 4, 2005.

Diagnosis. (1) Dentigerous process of vomer and vomerine teeth absent; (2) snout truncate in dorsal and lateral view; (3) tympanum covered by skin (not visible through skin); (4) dorsal skin in life and preservative from smooth to slightly shagreened; (5) ventral skin granular, presence of small cloacal enameled warts; (6) parietal peritoneum transparent, pericardium, visceral and hepatic peritonea white, all other peritonea transparent; (7) liver bulbous; (8) humeral spine absent; (9) webbing formula of fingers III 2 – 1 1/ 2 IV; (10) webbing on feet I 1 – 2 - II 1 – 2 III 2 – 2 IV 2 – 1 V; (11) low and weakly enameled ulnar and tarsal folds; (12) nuptial excrescences Type-V, comprised by a line of individual glands extended throughout the internal side of Finger I, glands not present in other fingers, prepollex not evident from external view; (13) Finger I longer than Finger II; (14) eye diameter larger than width of disc on Finger III; (15) color in life: dorsum with small yellow dots forming a light green reticulum dotted with dark small and minute melanophores, bones white; (16) color in preservative: dorsal surfaces cream with small and minute dark melanophores and white minuscule dots due to absence of pigments; (17) iris golden towards the pupil but with small white spots in external areas and black reticulation; (18) minute melanophores not extending throughout fingers and toes except on the base of Finger IV and Toe V; in life, tip of fingers and toes white; (19) advertisement call composed by a single note, first half pulsed and second tonal with increasing frequency, lasting 0.08– 0.09 s, dominant frequency of 5622.5–6065.9 Hz, males call from upper and underside of leaves; (20) fighting behavior unknown; (21) egg clutches deposited on underside of leaves, no parental care observed; (22) tadpole unknown; (23) adult size between 19.9–20.0 (N = 2) mm in males and 20.0 mm in one female.

Comparisons. Following Guayasamin et al. (2009), we place the new species in the genus Hyalinobatrachium because of the following characters: humeral spine absent in adult males, digestive tract and bulbous liver covered by white peritonea, completely transparent ventral parietal peritoneum, white bones in life, cream dorsal coloration in preservative, males lack conspicuous dorsal spicules during breeding season, nuptial pad small and restricted to the inner edge of Finger I in males (Type V), dentigerous process of the vomer and vomerine teeth absent, males vocalize from the undersides of leaves, and females deposit one layer of eggs on the undersides of leaves.

Hyalinobatrachium kawense sp. nov. most notably differs from all recognized species of Hyalinobatrachium in the following combination of morphological characters: snout truncate in dorsal and lateral views, bones white in life, dorsum with melanophores of two sizes (small and minute) in life and preservative, white pericardium, fingers and toes white, webbing formula of fingers III 2 – 1 1/ 2 IV, advertisement call composed by a single note, first half pulsed and second tonal with increasing frequency. Other relevant morphological, acoustic and genetic data are summarized in Tables 1, 3 and Figures 2 , 3, 7.

Additionally, Hyalinobatrachium kawense sp. nov. is similar in morphology and bioacoustics to H. carlesvilai , H. fleischmanni and H. tatayoi . However it can be differentiated from these three species due to the presence of white fingers and toes in H. kawense sp. nov. (yellow in H. carlesvilai , H. fleischmanni and H. tatayoi ).

Remarks. Our molecular data support Hyalinobatrachium kawense sp. nov. as a valid species because their sequences are reciprocally monophyletic with regard to all the other Hyalinobatrachium species analyzed (Fig. 3) and are relatively divergent (genetic distance ≥ 7 %). Guayasamin et al. (2008a) found strong support for H. kawense sp. nov. (referred therein as H. aff. mondolfii ) to be a member of a clade also including H. carlesvilai (referred therein as H. cf. munozorum from Bolivia), H. fleischmanni , H. mondolfii , H. munozorum and H. tatayoi . Nonetheless, its exact phylogenetic position within this clade could not be inferred with strong support (Guayasamin et al. 2008a).

Description of holotype. Adult male of small size, SVL 20.0 mm; head wider than body, HW 30 % of SVL; head wider than long (HW/HL = 1.3); snout truncate in dorsal view and profile; ES/EL = 0.9 and ES/IOD = 1.2; loreal region concave; nostrils prominent, round; internarial region depressed; canthus rostralis defined; eyes small, directed antero-laterally; EL 40 % of HL; tympanic annulus indistinct, tympanic membrane absent, supratympanic fold absent; dentigerous processes on vomers absent; choanae, circular, separated; tongue elongate, ovoid, not attached to mouth posteriorly for about one sixth of its length; vocal slits extending from the sides of the base of tongue to the level of the mandibular joints. Forearms slim; diameter of forearms about one and a half times the diameter of upper arms; low and enameled ulnar fold; humeral spine absent; relative length of fingers: II <I <IV <III; finger discs wide, truncated and larger than those of toes; FIII 40 % of EL; webbing absent between fingers I–II and basal between II–III, webbing formula on hand III 2 – 1 1/ 2 IV; subarticular tubercles round and small; supernumerary tubercles slightly appreciable; palmar tubercle round, thenar tubercle elongated; nuptial excrescences Type V, glands on the lateral fringes of fingers and the sides of membrane between fingers III and IV not observed; hind limbs slender; TL 50 % of SVL; low and enameled tarsal fold; discs of toes round, truncate in profile; inner metatarsal tubercle small and ovoid; outer metatarsal tubercle absent; supernumerary tubercles difficult to observe; webbing formula of feet I 1 – 2 - II 1 – 2 III 2 – 2 IV 2 – 1 V. In preservative, dorsal skin scarcely covered with enameled granules, area around tympanum almost granular; skin on belly and thighs granular, other ventral surfaces smooth; cloacal opening directed posteriorly at upper level of thighs, concealed by a dermal fold and flanked by small and enameled irregular folds and warts.

Color in life. Dorsal surfaces light green with dull yellow spots and dusted with melanophores of two sizes, minute and small. Low and enameled tarsal and dorsal folds. Cloacal ornamentation consisting of enameled warts and folds. Fingers and toes white. Iris golden with small white areas towards the eyelids and with greyish-brown dots spreading concentrically from pupil, where they appear at higher density. Parietal peritoneum transparent, pericardium, hepatic, and visceral peritonea white, peritoneum covering the gall bladder white, peritonea of all other internal organs not mentioned before transparent.

Color in preservative. General appearance cream. Dorsal surfaces dotted by a coat of minute and small dark melanophores, which leave uncovered cream spots. Dorsum with a fine layer of iridiophores only appreciable under magnification. Low enameled tarsal, ulnar and cloacal folds. Iris white. Other surfaces cream. Peritonea as stated above.

Variation. Measurements and body proportions of the holotype and paratopotype MNCN 44826 are presented in Table 2. Transparent peritoneum covering the gall bladder in paratypes MNHN 2011.0118, MTD 48142 and MTD 48143 while white in the other specimens. Paratopotype MNHN 2011.0119 has a darker appearance in its dorsal coloration due to a higher concentration of melanophores.

Advertisement call. A single high-pitched note that was clearly audible at long distances, the first half being pulsed and the second tonal ( Fig. 2 B). It lasts 0.08–0.09 seconds (0.09 ± 0.01). The dominant frequency is 5622.5– 6065.9 Hz (5825.5 ± 117.9) and the call rises in frequency from 4200.0–4992.0 Hz (4643.05 ± 214.1) at the beginning of the call to 6093.0–6482.0 Hz (6257.05 ± 118.2) at the end. The first half of all recorded calls starts with a group of short pulses (6–11) that shows a fast rise in frequency. The following half of the call consists of a tonal section at slightly increasing frequency. The maximum amplitude of the call is reached at the beginning of the tonal section.

Etymology. The name refers to the type locality Rivière de Kaw, close to the Atlantic coast of French Guian. This is so far the only known locality where the species has been recorded.

Biology and tadpole. Males generally call above leaves (occasionally on the underside) of moucou-moucous ( Montrichardia sp.) 3–4 m above the water. One male was observed calling (recorded) from the upper side of a Pachira aquatica leaf. When a gravid female with white eggs approached the male, this attempted to amplect with the female without success. Males form groups of about 10 individuals dispersed approximately every 100 m along the Kaw River. Eggs are laid on the underside of leaves; a clutch containing 33 eggs was photographed ( Fig. 7 F).

Ecology and distribution. This species has only been found in the flooded forest of Rivière de Kaw in French Guiana.

Figures

FIGURES 2. Comparative oscillograms and spectograms of advertisement calls of Hyalinobatrachium species from the Guiana Shield and H. fleischmanni: (A) H. fleischmanni from Panama, audio from Ibañez et al. (1999); (B) H. kawense sp. nov. from French Guiana, MNCN 44825; (C) H. cappellei Venezuela, MHNLS 17328; (D) H. cappellei French Guiana, audio from Marty and Gaucher (1999); (E) H. iaspidiense from Venezuela, MHNLS 13495; (F) H. iaspidiense from French Guiana, audio from Marty and Gaucher (1999); (G) H. mesai, holotype; (H) H. tricolor sp. nov. from type locality in French Guiana, uncollected specimen; (I) H. mondolfii from Venezuela, MHNLS 17120; (J) H. taylori from Venezuela, MHNLS 13496.

FIGURES 7. Adult males of Hyalinobatrachium kawense sp. nov. (A, B) holotype, MNCN 44825, SVL = 20.0 mm; (C) MNCN 44825, SVL = 19.9 mm; (D) MTD 48142; SVL = 19.0 mm; (E) MTD 48143, SVL = 20.0 mm; (F) egg clutch on the underside of a leaf.