Bioacoustics of Vitreorana gorzulae

Natural history and distribution. The ecology of Centrolene gorzulae was recently discussed by Kok and Castroviejo-Fisher (2008) , on the basis of specimens from Kaieteur National Park, Guyana . The species was recently discovered at a new locality, the southeast slope of Mount Maringma on the border of Guyana and Brazil ( ca. 1400 m elevation), and additional observations were made on clutch deposition. Four clutches were collected between 23–24 November 2007 ; three of them were found among moss on overhanging branches 1.5–2.0 m above water ( Fig. 5 ), the fourth clutch was found deposited between two leaves (attached to both), about 1.5 m above water. Many males were calling at night in the vicinity of the clutch deposition sites, but no male-male interaction was observed. Clutches contained 15– 22 eggs at various stages of embryogenesis, and no guarding males were detected. One female (IRSNB 14327, 20.9 mm SVL), collected on 22 November 2007 , contained 13 enlarged, partly pigmented, ovarian eggs, the largest with a diameter of 2.0 mm.

Diagnosis. This species is placed in the genus Centrolene because adult males have humeral spines (Ruiz- Carranza & Lynch 1991 ; Duellman & Señaris 2003 ). It differs from all other species of Centrolene by having a trilobate liver covered by a white peritoneum and a mostly transparent parietal peritoneum, with a small white anterior portion (the “bib-like white patch” of Duellman & Señaris 2003 ), which is only detectable in dissected specimens. Characterization. (1) dentigerous process on vomer and vomerine teeth absent; (2) snout subtruncate to truncate in dorsal view, truncate to slightly sloping in lateral profile; (3) tympanum distinct, small, oriented dorsolaterally with a slight posterior inclination; (4) dorsal surfaces shagreened; males with small spicules visible under magnification; (5) ventral skin strongly granular, cloacal ornamentation consisting of small enameled tubercles lateral to vent and enlarged paired round tubercles below vent; (6) parietal peritoneum mostly transparent, a small anterior portion white (the “bib-like white patch” of Duellman & Señaris 2003 ), only detectable in dissected specimens; pericardial peritoneum white; hepatic and visceral peritonea white, urinary bladder transparent; (7) liver trilobate; (8) humeral spine in adult males present; (9) finger webbing II 2 -– 3 III 2+–(2-–2) IV ; (10) toe webbing I (1–1½)–(2–2+) II 1–2 + III 1 –(2–2+) IV (2–2+)– 1 V ; (11) fringe on postaxial edge of Finger IV present, enameled, metacarpal fold present, weakly enameled, ulnar fold absent; fringe on postaxial edge of Toe V present, enameled, metatarsal fold present, weakly enameled, tarsal fold usually absent or very weak; (12) nuptial excrescences finely granular, white, consisting of a dense group of glands and situated in the medial, dorsolateral internal side of Finger I (Type-V); prepollex slightly enlarged; prepollical spine projecting (spine not exposed); (13) when appressed, Finger II = Finger I ; (14) diameter of eye about 2X width of disc on Finger III ; (15) in life, dorsum dark green with scattered paler flecks; (16) in preservative, dorsum lavender entirely covered with minute melanophores; (17) in life, iris metallic copper with dark brown reticulations; an incomplete pale yellow ring around pupil; (18) distribution of melanophores on digits variable, but always more numerous on Fingers III–IV than I and II ; Toes IV–V with many melanophores, rarely present on Toes I–III , if present, few and restricted to the two distal phalanges; in life, hands and feet bluish green to green, tips of fingers and toes yellowish green; (19) males call from the upper side of leaves; note single and pulsed (3–7 pulses per call), advertisement call of 0.02– 0.05 s duration, dominant frequency of 4416.97–5157.48 Hz; (20) combat behavior unknown; (21) clutches deposited on vegetation overhanging streams, in moss or between two leaves, clutch size 15– 22 eggs ( n = 4); none of the clutches observed were guarded; (22) tadpole unknown; (23) SVL in males 19.2–22.5 mm ( n = 11); in females 20.9–22.0 mm ( n = 4).