GBIF Taxonomic Backbone & Wikipedia Registry Profile
Description of the holotype. Figs. 5 – 6; measurements in mm. Adult male with long and slender body, slightly dorsoventrally flattened; snout – vent length 42.9; snout acuminate with rounded tip in dorsal view, narrowly rounded in lateral view; head length 15.8, approximately 27 % of SVL; head width 13.6; eye – snout distance 6.7; nostrils directed laterally; nostril closer to the snout (1.7) than to eye (4.7); eye diameter 6.1, slightly larger than tympanum diameter (5.2); interorbital distance 4.3; approximately one third of eye projecting above dorsal margin of head in lateral view; canthus rostralis distinct and sharply protruding; loreal region concave; anterocranial part of upper arm with large protruding gland (3.6 long, 2.0 wide, surface: 7.2 mm 2); long and slender fingers, tips broader than subarticular tubercles, forming discs, reaching 130 – 200 % of finger width, inner metacarapal tubercle large and elongated, outer metacarpal tubercle smaller and more rounded; manual webbing absent; finger formula II <I <III <IV; nuptial pads on anteroventral surface of first finger, almost transparent; thigh length 20.9, approximately half SVL; crus length 23.0; foot length including longest toe 32.5; single inner metatarsal tubercle large and elongated; single outer metatarsal tubercle small and round; toes long and slender, tips slightly broader than subarticular tubercles, forming small discs; toe formula I <II <V <III <IV; webbing formula I (0) II (1 - 0) III (1 - 0) IV (2 - 1) V (0); head and dorsum covered with small tubercles, becoming slightly larger from snout to middle of dorsum, decreasing in size towards lower back; narrow, distinct dorsolateral ridge extending from posterior corner of eye, reaching to posterior 1 / 3 of body, in last third broken into isolated small bumps; ventral skin smooth. Dorsal coloration in life (Fig. 6 a) medium brown with few darker spots; flanks greenish yellow, becoming paler ventrally with some darker mottling; arms slightly lighter brown than dorsum, marbled with fine, irregular, dark pattern; hind limbs slightly lighter brown than dorsum with narrow transverse dark bars; posterior parts of thighs marbled; foot webbing greyish brown; throat and belly white; ventral side of legs pale beige; hind limbs ventrally patterned with indistinct brown spots; bright, white upper lip extending posterior to angle of mouth, below and posterior to tympanum. After four years in preservation (75 % ethanol; Fig. 5), in general less saturated colors: brownish dorsal color darkened; greater contrast of marbled limb patterning; flanks lacking yellow coloration, now beige with small remnants of brownish speckles; white throat and lip more shiny. Variation. Measurements (in mm) of all individuals are summarized in Table 5. Overall, the male paratypes were similar to the holotype in external appearance and coloration. Male SVL ranged from 41.9 – 50.4 (mean ± sd: 45.9 ± 2.9, N = 13). The humeral gland area spanned between 3.7 – 14.8 mm 2 (9.4 ± 2.7 mm 2, N = 13). Female SVL ranged from 53.6 – 75.6 (63.9 ± 7.8, N = 10) thus markedly exceeding male SVL (Fig. 7). Seven of 13 showed slightly more extended (1 - 1), and a single male paratype showed slightly less extended webbing (2 - 2) of the fourth toe. In female paratypes seven of 10 individuals exhibited a webbing formula with slightly more extended webbing on toe IV (1 - 1). The dorsal skin was covered with small tubercles in all individuals, but females had fewer, smaller, and less spiny tubercles. In some individuals, the skin appeared almost smooth at first sight, but tiny granules were always present upon detailed inspection. The dorsolateral ridge was interrupted in the majority of specimens: females (six of 10) and males (nine of 13). Females showed a brighter brown dorsum and few to no dark spots (see Figs. 6 b, 7 b, 8 e, g, 11 c). On the dorsum of males, the ground color varied from chocolate-brown to dark brown and all males had at least some dark spots. The ventral coloration varied greatly among males. Among the paratypes, some had a plain white throat (e. g., ZMB 88549, 87112), similar to the holotype, whereas others exhibited dusty brown speckling covering almost the entire throat (e. g., ZMB 87113). The belly of all males were white to cream, and some individuals had irregular brown spots (e. g., ZMB 87110) that were densest near the legs, throat, or flanks, but were absent at the center of the venter. Females showed some color variation on the venter. In ZMB 87114, the belly and throat were white, whereas ZMB 79253 and ZMB 79197 had a cream-colored belly and a dusty brown speckled throat. Concerning life coloration (Figs. 8, 11), the dorsum exhibited various shades of brown, sometimes with darker spots (especially in males, most females without darker spots). The flanks in males were greenish yellow (Fig. 8 f, h) to chocolate brown dorsally (Fig. 8 b), usually turning lighter ventrally (but see Fig. 8 a). The flanks in females were olive green, turning paler ventrally (Figs. 8 c, e, g, 11 c), and becoming almost cream-colored towards the belly (then often with some greenish or brownish mottling). The tympanum was brown in both sexes. Males had a narrow green line surrounding the eyes. In both sexes the iris was golden, sometimes with a reddish tinge, with the lower half of the iris being darker. The limbs and dorsum were a similar shade of brown in both sexes. The limbs sometimes were somewhat lighter, but with darker patterning. The number of conspicuous dark transverse bars on the hind limbs varied among individuals (e. g. compare Figs. 8 b & 8 h). The venter was beige or cream. Both sexes had a light cream or white upper lip, and rarely the anterior part of the lip was brownish (Fig. 8 h). Juveniles showed a more contrasting pattern compared to adults. It consisted of a greenish brown dorsum with black spots and an almost black loreal region and flank. The ventral part of the flank and the belly were white with black dots. The juveniles had more conspicuous dark cross bands on the hind limbs and blackish dots on the forelegs; a bright white upper lip, and a bright red iris (uppermost part golden) (Fig. 11 f). Acoustics. The advertisement call of Amnirana parva sp. nov. consists of a whiny-voiced croaking sound with ascending frequency modulation from 932 to 1092 Hz (mean ± sd: 1030 ± 86, N = 3). The sound consists of up to five harmonics of which the second-lowest is the dominant one in the first half, the lowest one in the second half (Fig. 4 a). The call duration ranges from 0.26 – 0.78 s (0.52 ± 0.26, N = 3). Dominant frequency at the beginning of the call ranges from 948 – 1034 Hz (1004 ± 49, N = 3). All call characteristics are summarized in Table 4. A call description by Schiøtz (1964 c) from central Sierra Leone seems to refer to our new species. In that paper, Schiøtz describes three different sections of the call (such a clear distinction of sections was not detected by us). Call duration and complexity, however, seem to increase with the motivation of the frogs (MOR pers. obs.). Schiøtz (1964 c) also mentions that these calls were different from those he recorded in Cameroon for A. albolabris, though he did not provide further details.
