Description

Diagnosis: Ceuthomantids share five characters: (1) notched digital discs; (2) narrow heads; (3) green coloration; (4) absence of vomerine teeth; (5) absence of nuptial pads. Ceuthomantids also lack intercalary elements and Bidder's organs (Heinicke et al. 2009). Ceuthomantis cavernibardus can be diagnosed by the following combination of characters: (1) dorsal skin granular, weakly tuberculate; ventral skin areolate; (2) tympanum is distinct; (3) snout rounded to truncate when viewed from above, and rounded in profile; canthus rostralis distinct and rounded; (4) upper eyelid granular and lacking tubercles; (5) vomerine teeth absent; (6) males with vocal slits and a shallow subgular vocal sac, but no nuptial pads; (7) finger I shorter than finger II; (8) fingers bearing broad, medially notched discs and lacking fringes; (9) ulnar tubercles absent; (10) no prominent heel tubercle; (11) inner metatarsal tubercle oval, up to twice as long as the outer metatarsal tubercle; (12) toes unwebbed and unfringed but with weak lateral keeling and expanded, medially notched discs (smaller than finger discs); (13) dorsum usually green (sometimes brown), often has a dark hourglass or X-shaped marking; white median gular stripe and paired pectoral spots; (14) males measure about 27-31 mm in SVL, females measure 30-32 mm SVL (Myers and Donnelly 2007).

Similar species:
--C. smaragdinus: C. cavernibardus lacks paired dorsal gland-like protrusions, unlike its congener C. smaragdinus; in C. smaragdinus, a pair of gland-like structures is present on the posterior of the head and also in the sacral area. C. cavernibardus also does not have the distinct subconical tubercle on the upper eyelid and the heel that are present in C. smaragdinus (Myers and Donnelly 1997; Heinicke et al. 2009).

--C. aracamuni: C. aracamuni can be distinguished from C. cavernibardus by dorsal skin texture (areolate in C. aracamuni vs. granular to weakly tuberculate in C. cavernibardus); a shorter first finger (Finger I is 86% of the length of Finger II in C. aracamuni, vs. 94% in C. cavernibardus); a narrower head (34% of SVL in C. aracamuni vs. 37-41% of SVL in C. cavernibardus); snout profile (strongly truncate in C. aracamuni vs. rounded in C. cavernibardus) (Barrio-Amorós and Molina 2006).

--C. duellmani: C. cavernibardus can be distinguished by a lack of distinctive blue spots on concealed limb surfaces (vs. present in C. duellmani), finger I shorter than finger II (vs. equal in C. duellmani), absence of supernumerary tubercles on the hand (vs. present in C. duellmani), weak to faint lateral keeling on fingers and toes (vs. no lateral keeling on either fingers or toes for C. duellmani), coarsely granular belly skin (vs. areolate in C. duellmani), and a strong white gular stripe in some specimens (vs. very faint gular stripe in C. duellmani) (Barrio-Amorós 2010).

Description: The snout-vent length in males is about 27-31 mm and in females is about 30-32 mm. The head is narrow, being slightly longer than wide, and is as wide as the body. The snout is rounded to truncated in dorsal view, and is rounded in profile, with a distinct, rounded, slightly concave canthus rostralis and a slightly concave loreal region. Nostrils protrude slightly. The tympanum is distinct and is round or slightly higher than it is wide. The dorsal edge of the tympanum often slightly covered by a low supratympanic fold, with the fold extending from the eye to just short of the arm. The upper eyelid is granular and lacks tubercles. There may be a few postrictal tubercles, which are sometimes whitish in color. Choanae are round or tear-shaped and are not hidden by the palatal shelf of the maxillary arch. The tongue is round, or slightly longer than wide, with the posterior edge free and often slightly nicked. No vomerine teeth are present. Fingers have distinctive medially notched expanded discs. Relative adpressed finger lengths are III>IV>II>I. Finger I usually reaches the subdigital pad of finger II. The disc on finger I is smaller than that of fingers II-IV. The palmar tubercle is large and cordiform, while the thenar tubercle is oval. Supernumerary tubercles are round or elongated and smaller subarticular tubercles are rounded. Hind limbs are relatively long, with the heels overlapping when held at right angles to the sagittal plane. Relative lengths of adpressed toes are IV>V≥III>II>I. The toes are unwebbed, have weak lateral keeling and have smaller discs than those present on the fingers. Neither ulnar tubercles nor distinct calcar tubercles are present. The inner metatarsal tubercle is oval-shaped and up to twice as long as the outer metatarsal tubercle. There is no tarsal fold or tubercle. Some individuals have a row of small whitish tubercles that begins proximal to the outer metatarsal tubercle and ends nearly at the heel. Dorsally the skin is granular to weakly tuberculated, while the ventral skin is areolated (venter is coarsely granular) and the throat is smooth. A discoidal fold is present anterior to the groin. Males have vocal slits posterolateral to the tongue and a shallow subgular vocal sac, but lack nuptial pads. Sexual dimorphism in size is not pronounced, as females are only slightly larger than the males (Myers and Donnelly 1997).

In life, the dorsal surfaces are highly variable in coloration. Most individuals have at least some green, but a few were brown or olive brown. Most individuals have a dark brown hourglass or X marking on the dorsal surface, along with with bright green streaks and specks. Two of the brown specimens had darker brown on the head and shoulders. Ventral surfaces are blackish gray with scattered white dots. There is also a white gular stripe and paired white pectoral spots (one or two on each side) at the region of arm insertion. All specimens have a distinct pale interorbital line, which connects to the anterior edge of the hourglass/X mark, if present. A dark, poorly defined canthal stripe sometimes extends from the eye to the snout tip. Distinct yellowish or greenish lighter lines or spots may radiate from the eye across the lips, and from the upper lip to the underside of the lower lip. A thin vertical line of the same color is present on the tip of the snout, in line with the gular stripe. Arms sometimes show light and dark cross-banding, but all have dark wrist bands. Upper limbs sometimes have pale spots arranged as cross-banding. Two pale lines diverge ventrally from the vent, and there is also usually a dark seat patch. Posterior thighs are brown to blackish gray, often with gray specks. The iris is bright bronze-orange with a reddish brown horizontal stripe and black flecking on the lower half. Juveniles look like adults and vary from completely brown to completely green; generally juveniles also have the white gular stripe and white pectoral spots. Some juveniles were brown dorsally but had green coloration dorsolaterally and on the limbs. In juveniles, the hourglass/X marking on the dorsum is outlined by green or tan (Myers and Donnelly 1997).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Brazil, Venezuela

View distribution map in BerkeleyMapper.

Known only from the type locality in Venezuela. Specimens (6 males, 5 females, 7 juveniles) were collected during a six-day dry period (March 11-17, 1989) at an elevation of 1160-1200 m from the north base of Pico Tamacuari, Sierra Tapirapecó, Amazonas, Venezuela (this mountain straddles the border between Venezuela and Brazil) (Myers and Donnelly 1997). C. cavernibardus might occur more widely, in the southern and eastern Guiana Highlands, but this has not yet been confirmed (Heinicke et al. 2009). The habitat is wet montane forest. Adult males were found calling during the day on roots and moss in caves formed by granite boulders. Juveniles were found on leaf litter (Myers and Donnelly 1997).

Life History, Abundance, Activity, and Special Behaviors
This species has an unusual behavior for terraranans: diurnal calling. Males cease calling when a light is shone on them or they are being approached. Both sexes were found together in caves formed by large granite boulders during the day. They are very wary and hard to catch during the day. The capture of a female elicited a different call from her male companion. At night, frogs were easily caught perched on leaves about 1 m above the ground. These were perhaps sleeping (Myers and Donnelly 1997).

Male calls were recorded. Call length varies (1.6-11.2 seconds), with each call consisting of a train of loud notes. Note duration is 0.08-0.12 seconds. The fundamental frequency is about 1500 Hz (range 1480-1520 Hz), with a distinct harmonic at twice the fundamental frequency. The frequency is generally not modulated by the male, but two calls were recorded where the first note dropped rapidly from 2400 Hz to about 1400 Hz, with the second note beginning at 1400 Hz and then rising to 1520 Hz for the rest of the call. Notes are fairly constant and evenly spaced, although the first one or two may be shorter and softer. and the rate of note-repetition is positively correlated with temperature. Choruses may form after one male has initiated calling (Myers and Donnelly 1997).

C. cavernibardus breeds terrestrially and is assumed to have direct development of the terrestrial eggs. Eggs are large and unpigmented, as is typical of direct-developing terraranans. Developing embryos bear egg teeth (Heinicke et al. 2009).

Trends and Threats
Based on the frequency of calls heard, this species appeared to have been one of the most common in the area of the type locality at the time it was described (Myers et al. 1997). At least one population is found within a protected area, Parque Nacional Parima-Tapirapecó (Señaris and La Marca 2004).

Comments
The family name, Ceuthomantis derives from Greek roots: keuthos, meaning hidden (alluding to its hidden habitat in the tepuis), and mantis, meaning tree frog (Heinicke et al. 2009). The species name derives from Latin, caverna, meaning cave and bardus, meaning singer, and refers to the diurnal calling sites used by males (Myers and Donnelly 1997).

This species was originally described as Pristimantis cavernibardus by Myers and Donnelly (1997) but was transferred to the new family Ceuthomantidae and new genus Ceuthomantis by Heinicke et al. (2009).

The species originally reported as Pristimantis cf. cavernibardus from Sarisariñama Tepui (Barrio-Amorós and Brewer-Carías 2008) is not in fact conspecific with Ceuthomantis cavernibardus; it has recently been described as a new species, Ceuthomantis duellmani (Barrio-Amorós 2010).

References

Barrio-Amorós, C. (2010). ''A new Ceuthomantis (Anura: Terrarana: Ceuthomantidae) from Sarisariñama Tepui, southern Venezuela.'' Herpetologica, 66, 172-181.

Heinicke, M. P., Duellman, W. E., Trueb, L., Means, E. B., MacCulloch, R. D., and Hedges, S. B. (2009). ''A new frog family (Anura: Terrarana) from South America and an expanded direct-developing clade revealed by molecular phylogeny.'' Zootaxa, 2211, 1-35.

Myers, C. W., and Donnelly, M. A. (1997). ''A tepui herpetofauna on a granitic mountain (Tamacuari) in the borderland between Venezuela and Brazil: Report from the Phipps Tapirapecó Expedition.'' American Museum Novitates, 3213, 1-71.

Señaris, C., and La Marca, E. 2004. Ceuthomantis cavernibardus. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.4. www.iucnredlist.org. Downloaded on 05 March 2011.

Species Account Citation: AmphibiaWeb 2011 Ceuthomantis cavernibardus: Ranita Tamacuarina Cantora (Spanish) <https://amphibiaweb.org/species/5734> University of California, Berkeley, CA, USA. Accessed Nov 23, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 23 Nov 2024.

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