Myersiohyla

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 : 40-42

Myersiohyla sp.

Figures 29–30

The second author collected an adult female specimen (USNM 550357) of Myersiohyla on the summit of Cerro Duida (1850 m, 03°25′N, 065°40′W). The point of capture is approximately 25 km SE (straight line) from Cerro Culebra, the type locality of M. loveridgei . The specimen has differences in pattern with the two specimens described by Rivero (1961; “ 1971 ” [1972]) and subtle morphological differences; for these reasons we are hesitant to assign it to M. loveridgei until more data on the variation of this species becomes available. The specimen (fig. 29) differs from the holotype of M. loveridgei and the specimen described by Rivero (“1971” [1972]) in having the thighs with irregular tan spots, instead of welldefined vertical bars, and in having the tympanic annuli more inclined medially. Some measurements of this specimen are (all in mm): SVL 47.2; HL 18.0; HW 17.4; IND 3.7; IO 6.0; ED 5.3; EN 4.5; TD 2.5; TL 26.4; FL 20.1. Other morphological characteristics include a row of tubercles along the arm, quite prominent palmar and plantar tubercles (including an enlarged inner metacarpal tubercle; see fig. 30), a well-developed ridge along the tarsus, and foot webbing formula I 2–2 II 1½–2 III 2 + –2½ IV 2½–1 + V. Dorsally the background coloration is dark reddish brown, with multiple, irregular tan mottling. The discs are pale gray. A superficial dissection reveals a group of fibers of the m. depressor mandibulae that originates on the sheath of connective tissue that extends from the dorsal fascia into the space between the head and the body, with a few fibers originating at the level of the suprascapulae. This morphology is different from that seen in M. chamaeleo , as in that species the fibers originating at the level of the suprascapula form a distinct fan over the suprascapulae, while in Myersiohyla sp, most of the fibers originate in the connective tissue between head and body, with only the proximal part of approximately half of the fibers marginally reposing on the levator scapulae. The specimen is a gravid female. The dissected right ovary (left one intact) contained 47 eggs with largest diameters of 2.5–3.0 mm ẍ = 2.73; s = 0.15; n = 15), mostly unpigmented, with the exception of a reduced, pale brown animal pole.

Orejas-Miranda and Quesada (1976) referred to an unidentified hylid from the summit of Cerro Jaua and also mentioned tadpoles with numerous labial tooth rows. Further, they published a black-and-white photograph (their fig. 6) of an adult frog that unequivocally looks like a Myersiohyla . An adult male of Myersiohyla and some tadpoles with large LTRFs from Jaua are housed in the USNM (USNM 561349) and will be dealt with in a separate contribution.

DISCUSSION

THE MONOPHYLY OF MYERSIOHYLA

Although morphological synapomorphies are still unknown, Myersiohyla is recovered as monophyletic in the present phylogenetic analysis and supported with 91% parsimony jackknife absolute frequency in the static parsimony analysis. Besides the monophyly of Myersiohyla , the results of the analysis conducted need extensive discussion, but that requires a separate paper (Faivovich et al., in prep.), so we provide here some general comments that are expanded in appendix 1.

Our results recover the individual monophyly of Hyloscirtus , Bokermannohyla , and Aplastodiscus with 100% of absolute frequency in parsimony jackknife in the static alignment, while the monophyly of Hypsiboas , however, has 84% in parsimony jackknife. Relationships among the five genera, which are the same as those resulting from the analysis of Faivovich et al. (2005) and minor additions in subsequent analyses by Wiens et al. (2006, 2010) and Pyron and Wiens (2011), have at least 93% in parsimony jackknife. The internal relationships of Aplastodiscus and Bokermannohyla are the same as those obtained by Faivovich et al. (2005), Wiens et al. (2006, 2010), and Pyron and Wiens (2011). For comments on Hyloscirtus and Hypsiboas , see appendix 1.

Figures

FIG. 29. Dorsal and ventral view of Myersiohyla sp. (USNM 550357, 47.2 mm SVL). This specimen was collected on Cerro Duida, approximately 25 km SE (straight line) from the type locality of Myersiohyla loveridgei (Pico Culebra). It differs from the two known specimens of M. loveridgei in having the thighs with irregular tan spots, instead of well-defined vertical bars, and in having the tympana inclined more medially.

FIG. 30. Ventral view of hand and foot of Myersio- hyla sp. (USNM 550357). Scale bar = 5 mm.