Hylarana maosonensis Bourret 1937
Creators: name: Gawor, Anna
name: Hendrix, Ralf
name: Vences, Miguel
name: Böhme, Wolfgang
name: Ziegler, Thomas
Publisher: name: Zenodo
Year: 2009
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Amphibia
Anura
Ranidae
Hylarana
Hylarana maosonensis

description: Hylarana maosonensis Bourret, 1937
Series examined. Tadpoles of Hylarana maosonensis (ZFMK 87287-87305: n = 19) were collected in PNKB, U Bo region, Vietnam by R. Hendrix from June to August 2006. The larvae were collected throughout day and night time in primary forest streams, in ponds and in a catchment basin next to a forest road at altitudes between 530–700 m above sea level.
Adult specimens (ZFMK 86374, 86399-86400) were collected at night near primary forest streams and ponds within U Bo region of PNKB, Vietnam, at altitudes between 530–700 m above sea level.
Identification. Adult specimens (Fig. 1b; for measurements see Table 4) largely agreed with the descriptions by Bourret (1942), Inger et al. (1999), Ziegler (2002) and Ziegler et al. (2006). Sequence congruence between adults (ZFMK 86373, 86399-400) and tadpoles (ZFMK 87293-295, 87300, 87305; Fig. 2b) was 100 %. The following larval description is based on a single tadpole in Gosner stage 36 (Fig. 4; for measurements see Table 5). The tadpole specimen used for description and drawing originates from the same water body as the DNA voucher specimens (characters of the five DNA voucher specimens of the series ZFMK 87300, 87305, and 87293-87295: stages 28-40, BL 7.1-15.1 mm, NP 55 in stage 28, 78- 93 in stages 35-40, NK 26-29 per 0.5 mm). In this water body, also H. guentheri (adults only) and H. attigua (larvae) were found. The DNA voucher specimens fully agree morphologically with the described and drawn specimen, including the characters that diagnose H. maosonensis from H. attigua and H. guentheri (broad upper jaw sheath, finger-shaped marginal papillae, two submarginal rows of papillae, papillae strongly pigmented in their distal halfs, dark olive brown colour with broad dark spots and bright blotch on throat). The identification of the described specimen is therefore well supported.
Measurements Males (n = 3)
SVL 35.5 – 37.5 (36.50 ± 1.00) SL 6.0 – 7.0 (6.17 ± 0.76)
NL 2.5 – 3.0 (2.77 ± 0.25)
EN 3.0 – 3.2 (3.07 ± 0.12)
HW 12.5 – 13.8 (13.27 ± 0.68) HL 13.0 – 14.5 (13.57 ± 0.81) EE 7.0 – 8.5 (7.83 ± 0.76)
ED 5.5 – 6.0 (5.83 ± 0.29)
TD 3.5 – 4.0 (3.67 ± 0.29)
HaL 10.0 – 13.0 (11.17 ± 1.61) LL 70.0 – 75.5 (72.33 ± 2.84) FL 20.0 – 23.0 (21.67 ± 1.53) IMT 1.5 – 2.2 (1.90 ± 0.36)
Stage BH BL BW ED IND IP LF MTH NK NP 28 2.8 7.1 4.5 0.8 1.9 2.7 - - 29 55
3.7–4.3 8.8–9.2 3.0–5.7 1.0–1.1 1.0–1.1 3.1–3.3 0.9–1.0 4.3–4.5 26–28 48–60 30 (4. 0 0 (9. 0 0 (4. 7 3 (1. 0 3 (1. 0 3 (3. 1 7 (0. 9 5 (4. 40 (27 ±1) (54 ±8)
±0.30) ±0.20) ±1.50) ±0.06) ±0.06) ±0.08) ±0.07) ±0.14)
(n=3) (n=3) (n=3) (n=3) (n=3) (n=3) (n=2) (n=2) (n=3) (n=2) 32 4.7 10.0 6.3 1.8 2.1 3.7 1.3 5.7 32 87
4.9–5.1 11.1–12.6 6.8–7.0 1.5–1.6 2.2–2.6 3.8–4.3 29–30 77–80 35 (5. 0 0 (11. 8 5 (6. 9 0 (1. 5 5 (2. 4 0 (4. 0 5 1.3 5.8 (30 ±1) (79 ±2)
±0.14) ±1.06) ±0.14) ±0.07) ±0.28) ±0.35)
(n=2) (n=2) (n=2) (n=2) (n=2) (n=2) (n=2) (n=2) 36 4.7 12.7 7.2 1.6 2.7 4.4 1.2 6.1 34 85 37 6.6 12.8 7.8 1.8 2.8 4.5 1.9 7.2 29 - 38 5.9 12.1 7.6 1.6 2.6 4.6 1.6 6.7 27 90
6.0–7.5 13.7–15.1 8.4–10.8 1.8–2.1 2.8–3.1 5.3–6.2 1.0–2.2 7.2–8.0 27–30 78–98 40 (6. 8 2 (1 4. 5 2 (9. 5 8 (1. 9 0 (2. 9 6 (5. 6 2 (1. 6 4 (7. 58 (28 ±1) (89 ±9)
±0.63) ±0.54) ±0.90) ±0.14) ±0.11) ±0.36) ±0.46) ±0.30)
(n=5) (n=5) (n=5) (n=5) (n=5) (n=5) (n=5) (n=5) (n=5) (n=5) 41 6.5 12.3 8.1 1.9 2.3 5.0 0.8 6.0 29 - 42 6.1 12.3 8.2 2.1 2.3 5.0 1.4 5.2 28 -
5.1–5.2 11.1–11.5 6.40 1.9–2.0 1.3–1.4 3.7–3.8 0.5–0.7 4.1–4.2 - 45–62 43 (5. 1 5 (11. 3 0 (6. 3 8 (1. 9 3 (1. 3 5 (3. 7 5 (0. 6 0 (4. 13 - (54 ±12)
±0.07) ±0.28) ±0.04) ±0.11) ±0.07) ±0.07) ±0.14) ±0.04)
(n=2) (n=2) (n=2) (n=2) (n=2) (n=2) (n=2) (n=2) - (n=2) 2.6–3.2 3.6–4.1 1.0–1.5 9.4–10.4 33.0–35.0 47.7–49.8 3.8–4.2 3.8–4.1 2.6–3.0
40 (2.80 ±0.23) (3.86 ±0.21) (1.18 ±0.25) (9.80 ±0.41) (34.00 (48.75 (4.02 ±0.20) (4.02 ±0.13) (2.84 ±0.18)
±1.41) ±1.48)
43 (2.23 ±0.11) (1.86 ±0.34) (0.58 ±0.04) - 21.0 32.5 (2.60 ±0.28) (2.85 ±0.07) (1.48 ±0.04) (n=2) (n=2) (n=2) - (n=2) (n=2) (n=2) Colour pattern. Colouration of tadpole in preservative: body semitransparent, dorsolaterally light brown, greyish to yellowish, ventrally whitish. Body marbled with dark brown to dark green irregular spots. Dorsal and dorsolateral pigmentation of body is more dense than on the venter. On the ventral side, the throat and chest region is somewhat stronger pigmented especially around the oral disc. Tail musculature is yellowish, upper and lower tail fin almost transparent. The tail is covered with green to grey pigments and single dark brown irregular spots. Dorsolateral parts of hind limbs with green to grey pigments.
Colouration in life: body olive-coloured to brownish with gold-coloured pigments. Furthermore, body and tail covered with remarkable dark flecks. Iris of eye marbled with four black flecks at the outermost margin. Ventral side of body is transparent to white, intestinal spiral slightly visible, with a bright and slightly pigmented fleck at the throat. Internal gills reddish glimmering.
Description in dorsal view: Body of tadpole reaches a length of 12.7 mm, oval elongated, with a rounded snout. Maximum body width is between eye and spiracle (maximum body width 0.57 of body length). Nares anterodorsally positioned and directed, nearer to the tip of the snout than to the pupil (rostro-narial distance 0.50 of naro-pupilar distance). Internarial distance 0.61 of interpupilar distance. Eyes dorsolaterally positioned and directed, at the end of the first body third. Eyes are of remarkable size (maximum diameter of eye 0.13 of body length). Maximum interpupilar distance is 0.61 of body width. Muscles of tail are widest at base (width of tail musculature at base 0.44 of maximum body width).
Description in lateral view: Body laterally depressed (maximum body height 0.65 of maximum body width). Cone-shaped spiracle sinistral, laterally positioned at the beginning of the last third of body, posterodorsally directed. Vent tube separated from body. Distance of the spiracle opening from centre of eye is 5.4 mm. Vent tube ventromedially located between hind limbs. Outer wall of vent tube adhered to lower fin. Cloacal aperture is situated dextral in dorsal view. Tail length is 1.78 of body length, with a pointed tail tip. Tail musculature distinct (height of the tail musculature at base 0.70 of body height), running parallel from the base to the end of the first third of tail fin, then gradually tapering to the tip of the tail. Upper tail fin situated behind the base of tail, slightly convex, with maximum height at the last third of tail fin. Maximum height of lower fin is 0.55 of maximum height of upper fin.
Oral disc. Oral disc anteroventrally positioned (oral disc width 0.46 of maximum body width) and laterally emarginated. Oral disc framed by finger-shaped, marginal papillae except for a large medial gap on the upper labium. Marginal papillae of the lower labium elongated. Single submarginal papillae situated laterally at both ends of the beak between the upper and lower labium. Two additional rows of submarginal papillae situated on the lower labium. Pigmentation is somewhat stronger at the end of papillae. Keratodont row formula 2(2)/3(1), with about 34 keratodonts per 0.5 mm. Jaw sheaths black, robust, and serrated. Upper jaw sheath remarkably developed and curved with long appendices. Lower jaw sheath V-shaped.
Glandular Zones. Areas with a high density of secretory glands are oval-shaped, whitish and with dark brown pigments. Glands are situated on each side of the body, dorsally between the anterior corner of the eyes, dorsolaterally at midbody and laterally at the end of body. Additional secretory glands are situated ventrally on the throat and ventrolaterally before the hind limbs.
Measurements (in mm). BH 4.7; BL 12.7; BW 7.2; ED 1.6; IND 2.7; IP 4.4; LF 1.2; MTH 6.1; NK 34; NP 85; NPD 2.2; ODW 3.3; RND 1.0; TAL 22.6; TMH 3.3; TMW 3.2; UF 2.2.
Variation within the series. Series with 19 tadpoles in stages 28–43. Proportions vary as follows: BW 0.33–0.73 of BL, ED 0.11–0.18 of BL, IP 0.53–1.08 of BW, RND 0.22–0.69 of NPD, IND 0.34–0.70 of IP, TMW 0.33–0.73 of BW, BH 0.61–1.33 of BW, TAL 1.52–2.36 of BL, TMH 0.47–0.70 of 0.70, TMH 0.48–0.71 of MTH, UF 0.33–0.43 of MTH, LF 0.31–0.76 of UF, ODW 0.25–0.73 of BW. Keratodont row formula is homogenous within specimens. In earlier stages, oral papillae are less developed, the skin of body is more transparent and the internal organs are well visible in lateral and ventral view.
Natural history. Larvae of H. maosonensis were collected in a primary forest stream pool below a small cascade during the dry season between 20 June 2006 and 30 July 2006. The tadpoles were hidden on the ground between leaves and rock crevices. Further tadpoles were found in a water catchment basin next to the highway at km 51 and 53 in the U Bo region, Phong Nha – Ke Bang National Park, Vietnam, at 20 June, 7 July and 22 August 2006. These larvae were hidden between algae on the ground of the water body during day time (if algae were present, otherwise they were exposed on the sand or gravel of the ground), but were found swimming in the open water during night time. Once disturbed, the larvae tried to escape deep into the mud on the ground. During night time (08: 30 p. m.) of 7 July 2006, water temperature was 26°C. During day time, the water catchment basin was at least in part exposed to the sun. At day time of 22 August 2006 (12:00) the pH value was 5.5. Adult H. maosonensis (including calling males) were found during night time on forest stream rocks and cascades as well as around water catchment basins next to the highway at km 51 and 53 in the U Bo region between 20 June and 8 July 2006. Air temperature at night of 8 July 2006 next to a forest stream was 29°C. Once disturbed, the adult frogs tried to jump into the water where they remained motionless for some time.
description: Published as part of Gawor, Anna, Hendrix, Ralf, Vences, Miguel, Böhme, Wolfgang & Ziegler, Thomas, 2009, Larval morphology in four species of Hylarana from Vietnam and Thailand with comments on the taxonomy of H. nigrovittata sensu latu (Anura: Ranidae), pp. 1-25 in Zootaxa 2051 on pages 8-11, DOI: 10.5281/zenodo.186587