Myersiohyla loveridgei ( Rivero, 1961 )

Faivovich, Julián, Mcdiarmid, Roy W. & Myers, Charles W., 2013, Two new species of Myersiohyla (Anura: Hylidae) from Cerro de la Neblina, Venezuela, with comments on other species of the genus, American Museum Novitates 2013 (3792), pp. 1-63 : 38-40

Myersiohyla loveridgei ( Rivero, 1961)

Figures 26–28

Hyla loveridgei Rivero, 1961 . Type locality: “ Pico Culebra, Mt. Duida, 3000 ft., Territorio Amazonas.”

Hyla ginesi Rivero, 1963 . Replacement name for Hyla loveridgei , incorrectly considered a junior secondary homonym of Nyctimystes loveridgei Neill, 1954 (see La Marca and Smith, 1982).

Hyla loveridgei: La Marca and Smith, 1982 .

Myersiohyla loveridgei: Faivovich et al., 2005 . First combination with Myersiohyla .

DIAGNOSIS: A species of Myersiohyla characterized by: (1) male SVL 38.2, females unknown; (2) two nuptial pads; (3) a row of tubercles along the forearm; (4) an externally evident mental gland in males; (5) thighs patterned with longitudinal bars; (6) dorsum with irregular brown blotches; (7) condition of the m. depressor mandibulae unknown; (8) eggs unknown; (9), (10), (11) tadpoles unknown.

COMPARISON WITH OTHER SPECIES: Myersiohyla loveridgei is most similar to M. aromatica, from which it apparently differs by the presence of a distinct tarsal ridge (absent in M. aromatica; Ayarzagüena and Señaris, “1993” [1994]). The presence of two nuptial pads differentiates M. loveridgei from M. inparquesi, M. kanaima, and M. neblinaria. Dorsal color pattern and the presence of a row of tubercles along the forearm separate M. loveridgei from M. chamaeleo. The presence of an externally evident mental gland separates M . loveridgei from M. kanaima and M. neblinaria .

DESCRIPTION: The descriptions provided by Rivero (1961, “ 1971 ” [1972]) are adequate, but a few details are worth noting. Rivero (1961) described the nuptial pad of the holotype as “male with a brown rugosity on the pollex and inner finger....” Later Rivero (“1971” [1972]) described the second specimen (UPRM. 2854) as having “a smooth nuptial excrescence that extends up to the second finger.” We had access only to the holotype MCZ 28565, an adult male (fig. 26). Like M. aromatica and M. chamaeleo , it shows two contiguous, discrete nuptial pads covered with minute epidermal projections. One of the pads is on the prepollex, and the other is on the medial-proximal surface of the first digit ( fig. 27 ). The presence of a mental gland that occupies most of the gular region (fig. 28) is another characteristic overlooked by Rivero. Rivero (1961) reported that the holotype has the “vomerine odontoids forming a /--\ figure.” Our study of the same specimen suggests that the expression used by Ayarzagüena and Señaris (“1993” [1994]), “slightly S- shaped” is quite appropriate to describe the disposition of each vomerine tooth series. There are 12 teeth on the right and 13 on the left. Rivero (1961) described a slight tarsal fold in the holotype; we consider it more appropriate to describe it as a distinct tarsal ridge. Foot-webbing formula for the holotype is I 2–2 + II 1 + –2½ III 1½–2½ IV 2 + –1 + V. Some approximate measurements of the holotype (the specimen is quite contorted, all in mm) are: SVL 38.2; HL 14.1; HW 13.3; IND 3.1; IO 4.8; EN 3.7; ED 4.2; TD 2.1; TL 22.0; FL 16.4. Note that Rivero (1961) reported the SVL of the same specimen to be 42.0 mm.

REMARKS: The former Hyla loveridgei as described by Rivero (1961) was based on a single male specimen from Cerro Duida, and that description was supplemented (Rivero, “1971” [1972]) with an additional male (SVL reported as 45 mm) from the same locality. Since its description, the species has rarely been mentioned in the literature (see Rivero, 1963; La Marca and Smith, 1982). While we still do not know any morphological synapomorphy for Myersiohyla , we find loveridgei to be very close morphologically (if not a senior synonym of M. aromatica , see below) to various species included in Myersiohyla , and for this reason we pose the testable hypothesis that loveridgei is congeneric. As morphological synapomorphies are discovered for Myersiohyla , or tissues of loveridgei become available, its generic status should be reevaluated.

We did not study specimens of Myersiohyla aromatica . Based solely on the thorough description provided by Ayarzagüena and Señaris (“1993” [1994]), the only character states differentiating this species from M. loveridgei seem to be the presence of a distinct tarsal ridge in the latter (Ayarzagüena and Señaris, “1993” [1994]). Since the distinctiveness of this ridge as described earlier in this paper is variable in M. neblinaria , the diagnostic value of the character is tentative and needs further evaluation. Furthermore, Ayarzagüena and Señaris (“1993” [1994]) reported 30–34 total vomerine teeth, whereas the holotype of M. loveridgei has 25. However, the lack of other specimens of M. loveridgei and potential variation in vomerine tooth counts precludes any conclusion regarding the diagnostic value of vomerine tooth number. Given that the type locality of M. loveridgei (“Pico Culebra, Mt. Duida, 3000 ft., Territorio Amazonas ”) is approximately 40 km (straight line) from the type locality of M. aromatica (“Cumbre del Tepui Huachamacari, Estado Amazonas, Venezuela ”), and that Ayarzagüena and Señaris (“1993” [1994]) did not compare the species, we tentatively consider both species as valid, but suggest that their status deserves further study.

ECOLOGY AND NATURAL HISTORY: The holotype was collected during the day “as it sprang from beneath (or near?) a rock in a treeless, rocky area of Mt. Duida” ( Rivero, 1961: 109). The other known specimen was collected on the mossy stones along a fast-running stream (Rivero, “1971” [1972]: 185) .

ADVERTISEMENT CALL: Unknown.

TADPOLE: Unknown.

Figures

FIG. 26. Dorsal and ventral view of the holotype of Myersiohyla loveridgei (MCZ 28565, 38.2 mm SVL).

FIG. 27. Nuptial pad of the holotype of Myersiohyla loveridgei (MCZ 28565). Scale bar = 2 mm.

FIG. 28. Ventral view of the gular region of the holotype of Myersiohyla loveridgei (MCZ 28565) showing the external aspect of the mental gland. Scale bar = 5 mm.