Megophrys (Panophrys) fansipanensis, Tapley, Cutajar, Mahony, Nguyen, Dau, Luong, Le, Nguyen, Nguyen, Portway, Luong, and Rowley

Tapley, Benjamin, Nguyen, Luan Thanh, Cutajar, Timothy, Nguyen, Chung Thanh, Portway, Christopher, Luong, Hao Van & Rowley, Jodi J. L., 2020, The tadpoles of five Megophrys Horned frogs (Amphibia: Megophryidae) from the Hoang Lien Range, Vietnam, Zootaxa 4845 (1), pp. 35-52 : 44

Megophrys (Panophrys) fansipanensis

Figs. 3B and 5

Molecular data: 16S sequences were generated from tissue samples collected from two tadpoles ( VNMN010901 & HLNP 20171230 00011) and uncorrected p -distance between these sequences and that of the holotype of Megophrys fansipanensis also collected on Mount Fansipan , Sa Pa District, Lao Cai Province, Vietnam (GenBank accession number MH 514886 ) was 0.0 %.

Collection site: The following tadpole description is based on two specimens ( VNMN010901 & HLNP 20171230 00011) at Stage 35. Specimens were collected from a small pool in a 1 m wide low-gradient stream in disturbed evergreen forest on Mount Fansipan , Hoang Lien National Park ( HLNP), Sa Pa District, Lao Cai Province, Vietnam (22.3281°N 103.7817°E, 2242 m asl; Figs. 1 and 2C ), collected on 30 December 2017 by Luan Nguyen and Chung Nguyen .

Morphology: The body is elongated and slender; the nares are oval and their rims raised from the body wall, the nares are closer to the eyes than to the snout; the internarial distance is less than the interorbital distance; the eyes are positioned dorsolaterally, the pupils are round; the spiracle is sinistral and the spiracular tube protrudes from midway along the body wall just anterior to the maximal trunk width and opens laterally; the tail length ranges from 69.1–72.1% (n =2) of the total length; the dorsal tail fin inserts behind the body-tail junction, the dorsal fin is low, particularly towards the proximal half of the tail length; the basal tail width ranges from 53.1–60.3%, (n =2) of the maximal trunk width; the tail tip is pointed; the oral disc is subterminal and antero-dorsal; the lateral corners fold medially and turn upward when not fully extended (and in preservative), the width of the umbelliform oral disc makes up 74.1–82.9%, (n =2) of the maximal width of the trunk; in life the maximal BW is 64.8% (n =1) the maximal width of the fully extended ODW; the lower lip is bi-triangular shaped when fully expanded in live specimens; marginal papillae are absent; five rows of submarginal papillae are present on the upper lip when they are counted medially at the maximal width of the oral disc; these are regularly positioned and rounded, and become substantially smaller in the outermost row; five rows of rounded submarginal papillae are present on the lower lip when they are counted medially at the maximal width of the oral disc; these are regularly positioned, longitudinally oblong shaped at the edge of the disc and become increasingly rounded towards the point at which the maximal width of the disc is at its greatest, the submarginal papillae become smaller and more longitudinally elongated in shape on the outermost row; the lower lip is deeper than the upper lip; labial teeth are absent; the upper jaw sheath is serrated and has a medial notch; the lower jaw sheath lacks a medial notch. See Table 1 for measurements.

Colour in life: ( Fig. 5 ) Dorsally, the head and body are brown with dark brown speckles which become increasingly dense towards the posterior half of the body; there are obvious pale neuromasts; the oral disc is a translucent beige brown with dark brown submarginal papillae; the dorsal apex of the tail has a light brown saddle, the margins of which are bordered by a dark brown band on the lateral surfaces of the tail, this saddle extends from the body and terminates half way along the length of the tail; at the point where the tail meets the body there is a brown stripe that extends from the body-tail junction and runs along the midline of the lateral tail surface, this stripe becomes increasingly broken and fades into brown blotches half way along the tail; the dorsal and ventral tail fins are opaque, pale yellowish brown with a few dark brown speckles; the venter is a translucent grey brown and speckled with metallic blue and flecked with dark brown; the gills and coils of the gut are visible in the ventral view through the transparent ventral skin; the sclera of the eye is broad and black with green-gold flecks; the pupil is black and rounded; the iris is orange and speckled with black dots; the outer margin of the upper jaw sheath is dark brown.

Colour in preservative: ( Fig. 3B ) The body is brown with darker speckles; the oral disc is a translucent grey brown with dark brown submarginal papillae; the dorsal and ventral fins are opaque, pale grey brown with darker speckles; the venter is speckled grey and brown.

Variation: HLNP 20171230 00011 is larger than VNMN010901 ( Fig. 5 ) The ventral surface of the body of VNMN010901 is more densely speckled with metallic blue. TMW/BW is greater in HLNP 20171230 00011.

Figures

FIGURE 1. Survey sites in the Hoang Lien Range. Blue star, Megophrys gigantica and Megophrys jingdongensis tadpole collection site; blue square, Megophrys hoanglienensis tadpole collection site; blue circle, Megophrys fansipanensis tadpole collection site; blue triangle Megophrys maosonensis tadpole collection site. Pale grey areas indicative of higher elevation, dark green indicative of lowest elevation.

FIGURE 2. Collection sites in the Hoang Lien Range: (A) Megophrys gigantica and Megophrys jingdongensis tadpole collection site, Bat Xat District; (B) Megophrys hoanglienensis tadpole collection site, Tam Duong District; (C) Megophrys fansipanensis tadpole collection site, Sa Pa District, and (D) Megophrys maosonensis tadpole collection site, Sa Pa District.

FIGURE 3. Tadpoles of five Megophrys species from the Hoang Lien Range in preservative: (A) Megophrys gigantica (VNMN010899); (B) Megophrys fansipanensis (HLNP 20171230 00011); (C) Megophrys jingdongensis (VNMN010902); (D) Megophrys hoanglienensis (VNMN010903) and (E) Megophrys maosonensis (VNMN010904). Scale bar is 0.5 cm.

FIGURE 5. Megophrys fansipanensis tadpoles. (A) Dorsal, lateral, ventrolateral views, and detail of the oral disc in a live tadpole VNMN010901. (B) Lateral, dorsal and ventral views of the live tadpole HLNP 20171230 00011. 10 mm scale.