Ornate frog
Hildebrandtia ornata
Description 4
Diagnosis: Medium sized plump frog; typical Y-shaped pattern on throat; characteristic dorsal pattern.
Description: A plump, medium sized ranid with a blunt snout. The one adult female ever collected in Comoé National Park measured 38 mm (SVL). A male reared in captivity reached 67.1 mm SVL. Males have paired lateral vocal sacs whose slits are situated immediately anterior to the armpit. When inflated, they almost touch each other in front of the snout (Amiet 1974b). The large tympanum is set apart from the eye and is barely visible on young animals, but conspicuous on adults. It equals 0.5–0.6 of the eye diameter. Comparatively short hind limbs. Both thigh and lower leg reach just half of the SVL. The short hands reach 0.2 of the SVL. The inner metatarsal tubercle reaches at least more than 0.5 of the shortest toe length, or even surpasses its length. Webbing formula: 1 (1), 2 i/e (1–0.5), 3 i/e (2–1), 4 i/e (2.5), 5 (1).
Poynton (1964a) and Lambiris (1989) give a maximal length of 65 mm. Lambiris (1980) even gives 70 mm (SVL). Boulenger (1907a) mentions 48 mm. Schmidt & Inger (1959) describe nuptial pads developing on the first three digits, including their bases, of male H. ornata moeruensis (see below).
Voucher specimens:SMNS 8948 1–10 + tadpoles.Coloration: A broad green vertebral band runs from the snout tip to the end of the body. It either covers all of the snout or, in most specimens, it is split up immediately into three separate stripes. In this case, the median one will continue to the end of the body. Like the remaining green parts, it tends to be replaced on adult frogs by clear brown colors, that expand from the flanks. The two lateral green lines run from the outer border of the eyelids to the end of the body. Even on young individuals, they tend to be fragmented, forming various dots and strokes. Wherever the green colors fade, they are replaced by brown ones. The space between those at least partially green lines is occupied by two parallel brown lines. Some young have a back which is completely green. The basal section of the eyelid is pale to dark brown; in the former case, it often bears dark brown spots with black borders.
A narrow white stripe begins at the snout tip, i.e. below the green lateral stripe, crossing the eye at a level superior to the pupil and fading out somewhere behind the eye. This stripe is ventrally accompanied by a small dark brown triangle with black borders which stretches from the snout tip to the shoulder. In the caudal section of this triangle, however, only the borders and the tympanum keep their dark coloration, the remaining parts of the skin being rather dark gray. The tympanum partially shows a narrow white border. The upper lip is white up to the armpits. In the sector preceding the eye, a short green stripe occasionally appears. A broad pale to dark red line starts at the posterior border of the eye, i.e. above the dark zone surrounding the tympanum, running obliquely towards the groin. A rather short extension of this line starts above the armpits, bending back first towards the latter and finally pointing down perpendicularly. This extension also crosses the temporal triangle which runs to the belly where it becomes gray, bearing numerous black to dark brown spots and strokes. The diagonal red brown and the greenish dorsolateral lines enclose a triangle pointing towards the head. This area shows a dark brown color, especially on young frogs, whereas adult individuals have only continuous dark borders and a number of dark patches left. The rest of the triangle turning gradually rather pale.
The shoulder also bears a dark triangle, and the rest of the upper arm is beige to flesh-colored. Two elongate dark brown triangles pointing towards the hands appear on the lower arms. The hind limbs bear dark brown lines, two on the thigh, three on the lower leg. The outer parts of the thighs are mottled. The proximal parts of the lower legs often show green intervals separating the above-mentioned bars. The foot is clear brown with four to five dark transverse bars.
The throat bears two more or less symmetrical y-shaped white markings whose short branch point towards the corners of the mouth. Individuals from the Comoé National Park usually lack the shorter branch of the Y. The white markings are usually framed by dark brown to black bands. The remaining skin areas are paler brown, with the exception of the jaw borders and of the corners of the mouth which are both dark. The venter is whitish. The pectoral region and the flanks may be brown, too. The vocal sacs of the males are slate gray. In alcohol the green colors completely fade, turning red-brown. Some brown areas may turn red or reddish. Many markings either fade or disappear, being replaced at worst by a uniform dark brown. In this case, the frogs can only be identified by means of their throat markings; however, most individuals still show faint traces of the general markings.
Voice: At Comoé National Park, the advertisement call has been heard only occasionally. A male uttered squawking release calls when gripped at the inguinal region. Amiet (1974b) describes the advertisement call as a very low sonorous "hôn" which is uttered slowly and at very regular intervals over a long period. Each call lasts about 0.2 to 0.3 sec. Passmore & Carruthers (1995) report on a long nasal "quack" lasting 0.4 sec at a frequency of 0.4–0.6 kHz. According to Lambiris (1989), the low frequent call, "quack", lasts 0.5 sec, being repeated every two seconds.
This account was taken from Rödel, M.-O. (2000), Herpetofauna of West Africa vol. I. Amphibians of the West African Savanna, with kind permission from Edition Chimaira publishers, Frankfurt am Main.
For references in the text, see here
Sources and Credits
- (c) Jakob Fahr, some rights reserved (CC BY-NC), uploaded by Jakob Fahr
- (c) 2009 Frank Teigler, some rights reserved (CC BY-NC), http://calphotos.berkeley.edu/cgi/img_query?seq_num=289379&one=T
- (c) 2009 Frank Teigler, some rights reserved (CC BY-NC), http://calphotos.berkeley.edu/cgi/img_query?seq_num=289380&one=T
- (c) AmphibiaWeb © 2000-2015 The Regents of the University of California, some rights reserved (CC BY), http://eol.org/data_objects/34268632
