Tepuihyla tuberculosa (Boulenger, 1882)

Ron, Santiago R., Venegas, Pablo J., Ortega-Andrade, H. Mauricio, Gagliardi-Urrutia, Giussepe & Salerno, Patricia E., 2016, Systematics of Ecnomiohylatuberculosa with the description of a new species and comments on the taxonomy of Trachycephalustyphonius (Anura, Hylidae), ZooKeys 630, pp. 115-154 : 126-129

Taxon classification Animalia Anura Hylidae

Tepuihyla tuberculosa (Boulenger, 1882)

Hyla tuberculosa Boulenger 1882. Holotype BMNH 1947.2.13.34

Ecnomiohyla tuberculosa : Faivovich et al. 2005

Holotype.

Sub adult female with SVL 67.6 mm (Fig. 4 C–E). The description of the holotype provided by Boulenger (1882) is adequate.

Diagnosis.

In this section coloration pertains to preserved specimens unless otherwise noted. A large-sized Tepuihyla differing from other known species in the genus by the following combination of characters: (1) SVL in males 79.3-86.2 mm (n = 5), SVL in females 67.6-85.7 mm (n = 2); (2) skin on dorsum coarsely tuberculate, covered by small tubercles with scattered large tubercles; tubercles without keratinized tips; (3) skin on flanks covered by large tubercles; (4) webbing between fingers extensive but without reaching the proximal border of the disks, hand webbing formula I2 -2 II1 -2 III 1½ -1IV to I2-2+II1-2III2 -1IV (Fig. 7A); webbing between toes extensive and reaching the proximal border of the disks on at least three toes, foot webbing formula I0+-1+II0+-1 III0+-1+IV1+- 0+V to I1+- 1½II1-1+III1+-1½IV1½ - 0+V (Fig. 7B); (5) dorsal coloration in life greenish cream or brownish cream with scattered dark brown reticulations, anterior and posterior surfaces of thighs and hidden surfaces of shanks yellowish orange; (6) ventral coloration whitish cream and webbing between fingers and toes pale orange; (7) suborbital mark absent, clear labial stripe present, faint and with some brown spots; (8) coloration on flanks similar to dorsal coloration except for greenish yellow axilla and groins and whitish gray ventrolateral area; (9) skin on upper surface of head not co-ossified with underlying cranial elements, cranial crest slightly exostosed; (10) in life, bones green; (11) small triangular dermal flaps form serrate fringe along the ventrolateral margin of the forearm and along the outer edge of Finger IV; heels bearing two or three enlarged fleshy conical tubercles surrounded by few smaller round tubercles; small triangular dermal flaps form serrate fringe along ventrolateral margin of tarsus and outer margin of Toe V; (12) adults, in life, have cream iris with a coppery hue and scattered thin black reticulations; (13) vocal sac is white, single and subgular, (14) a juvenile is similar to adults in coloration but with dorsal background coloration brownish cream and a black medial stripe in the iris; (15) larvae unknown.

Tepuihyla tuberculosa differs from all congeneric species (in parenthesis), except Tepuihyla shushupe sp. n., in having a larger size: SVL in males 79.3-86.2 mm (n = 5), SVL in females 67.6-85.7 mm (n = 2) (maximum SVL 59.2 mm in other Tepuihyla ), having extensive webbing in the hands (basal webbing) and a serrate fringe along the ventrolateral margin of the forearm (absent). Other differences are listed on Table 4.

Tepuihyla tuberculosa is most similar to Tepuihyla shushupe sp. n. It differs from Tepuihyla shushupe sp. n. (character states in parenthesis) in having cream iris in life (iris cream with reddish periphery), dorsum covered with small tubercles intermixed with few large tubercles (dorsum covered with small tubercles intermixed with abundant large tubercles; Figs 3-5); in preservative, its dorsum is light cream or cream with a coppery hue and brownish cream to creamy coppery large tubercles (dorsum light brown with large brownish cream or creamy coppery tubercles with a dark brown posterior border). Tepuihyla tuberculosa also resembles the Amazonian Trachycephalus cunauaru and Trachycephalus resinifictrix but differs from both species in having serrate fringes on the limbs and tubercles on the lower jaw (both absent in Trachycephalus ; Fig. 8). Tepuihyla tuberculosa is easily distinguished from all other large Amazonian treefrogs in having fully webbed hands and feet, coarsely tubercular skin on dorsum, and serrate dermal fringes on the outer margin of the forearm and foot. Cruziohyla craspedopus and Dendropsophus marmoratus also have dermal fringes on the outer margin of the foot, but the former is distinguished by its deep green dorsum, vertically elliptical pupils in a bicolored iris (pale silver with yellow borders), smooth skin on dorsum and elongate calcar on the heel. The smaller Dendropsophus marmoratus exhibits a bright yellow belly with black spots or mottling (uniform yellowish-tan in Tepuihyla tuberculosa ).

Variation.

In this section, coloration refers to preserved specimens unless otherwise noted. Morphometric data for adult specimens are summarized in Table 5, whereas variation in dorsal coloration of preserved specimens is shown in Figure 5. Dorsal coloration varies between light cream (e.g., QCAZ 55423) and cream suffused with a coppery hue (e.g., QCAZ 52855) with brownish cream or creamy coppery enlarged tubercles, bearing scattered dark brown reticulations or marks. In all specimens the belly and ventral areas of thighs are lighter than those of the holotype probably because they were collected more recently. Head is rounded in dorsal view, wider than long; the snout is truncate in dorsal view and truncate (e.g. QCAZ 32716) in profile. The largest male has 86.2 mm SVL (average = 82.9 ± 2.7 mm, n = 5) and the largest female 85.7 mm (Table 5).

Coloration in life.

Dorsal coloration is greenish cream with scattered brown marks or reticulations, top and sides of head are more greenish in some specimens (e.g. QCAZ 52855); lips greenish with scattered small dark brown marks; supratympanic fold delineated by a thin brown edge, tympanic membrane lighter than the background; flanks with coloration similar to dorsum; axilla and groin pale orange, ventrolateral region whitish cream, limbs with faint brown transversal bands; dorsal surfaces of hands and feet, including webbing, greenish cream with scattered dark brown marks; discs pale green. Throat, chest and belly are white but some specimens have an orange hue on the belly (e.g. QCAZ 55423); serrate fringes along forearms and tarsus white; webbing, thighs and concealed surfaces of shanks orange. Iris is cream with a light coppery hue bearing some scattered black venations. Juvenile specimen QCAZ 55413 is similar to adult specimens but has a brownish cream dorsum with scattered faint brown blotches (Fig. 3 E–F).

Advertisement call.

Quantitative characteristics of the advertisement call of Tepuihyla tuberculosa (QCAZ 53699) are detailed in Table 3. The call consists of a cackle of short notes repeated at a fast rate with amplitude modulation (Fig. 6). Note amplitude and note rate increase markedly along the first half of the call, decreasing at the end. The call has two harmonics but most of the energy located on the first. Fundamental frequency of the notes ranges from 515.6 to 796.9 Hz (mean = 619.1, SD = 77.2). Two notes located at ~50% of the call duration have their greatest energy in the second harmonic, at 1078.1 and 1195.3 Hz. All other notes have their greatest energy in the first harmonic. The dominant frequency of the entire call ranges from 562.5 to 632.8 Hz. Interestingly, the call of this species is feared by natives in the lower Pastaza basin (Shiwiar, Sapara, Shuar, Achuar people), because it is commonly confused with the “calling” of the bushmaster Lachesis muta ( Squamata : Viperidae ). This belief almost certainly incorrect as Lachesis muta cannot vocalize. See also the Etymology section in Ecnomiohyla shushupe sp. n. description.

Distribution and natural history.

Localities documented for this species are shown in Figure 9. Duellman (1974) reported four specimens: two from Pastaza province in Ecuador, one from the mouth of Rio Santiago in northern Peru, and one juvenile from Rio Uaupes at junction of Rio Querari, Amazonas, Brazil. Given its geographic location, the latter probably corresponds to Tepuihyla shushupe sp. n., but its identity requires confirmation. We recorded five additional localities in the Amazon lowlands of Ecuador and two in Peru (Fig. 9). Elevation range is 132 to 1076 m above sea level. The southernmost and highest locality is Cordillera Escalera, San Martin department, in northeastern Peru (CRBIIAP 1252).

All specimens with ecological data were collected at night perching on vegetation 1.5 to 3.0 m above the ground. One specimen from Yasuní (QCAZ 52855) and one from Juyuintza (QCAZ 53542; Fig. 10B) were collected on primary forest (M. Read and H. M. Ortega-Andrade field notes). The specimen recorded at Juyuintza was calling from a tree hole 1.5 m above the ground in Terra Firme forest. The hole had a depth of ~15 cm and a diameter of 10 cm, and was ¾ flooded with water. Two individuals were calling nearby, at distances of approximately 100 to 200 m. No amplectant pairs, clutches, or tadpoles have been observed.

Conservation status.

The scarcity of records of Ecnomiohyla tuberculosa , even at thoroughly sampled localities, like Yasuni National Park, could be a consequence of small populations sizes or an artifact of low capture probabilities. Our finding of a male calling from a tree hole containing water suggests that Ecnomiohyla tuberculosa breeds on tree holes and is unlikely to be found on ground-level surveys. Therefore, lack of records probably results from low capture probabilities consequence of microhabitat preferences. Because population status is unknown, we suggest that the Red List category of Tepuihyla tuberculosa is Data Deficient according to IUCN (2001) guidelines. Searches of the species will benefit from audio sampling to detect the advertisement call described here.