Amolops ottorum, Pham & Sung & Pham & Le & Ziegler & Nguyen, 2019

Pham, Anh Van, Sung, Nenh Ba, Pham, Cuong The, Le, Minh Duc, Ziegler, Thomas & Nguyen, Truong Quang, 2019, A new species of Amolops (Anura: Ranidae) from Vietnam, Raffles Bulletin of Zoology 67, pp. 363-377 : 368-374

Amolops ottorum , new species

( Figs. 3–5 )

Holotype. IEBR 4342 (Field No. SL 2016.301), adult female, collected by NB Song and TV Dau on 28 October 2016 in the forest near Nam Nghiep Village (21°34.956′N, 104°17.160′E, at an elevation of 2.125 m), Ngoc Chien Commune, Muong La District, Son La Province, Vietnam.

Paratype. TBU 06 (Field No. SL 2016.514), adult female, collected on 10 November 2016 (the same data as the holotype) .

Diagnosis. The new Amolops species from Son La Province is assigned to the A. mantzorum species group on the basis of the following characters: the absence of a dorsolateral fold and the absence of circummarginal groove on the disc of the first finger ( Fei et al., 2009, 2017). The new species is also supported as a member of the A. mantzorum species group based on the molecular analyses ( Fig. 2 ). Amolops ottorum , new species is distinguishable from its congeners by a combination of the following morphological characters: (1) size small (SVL 47.5–48.2 mm in females); (2) head longer than wide; (3) vomerine teeth absent; (4) snout short (SE/ SVL 0.14–0.15); (5) tympanum dark brown, small (TD/ED 0.36–0.37 in females); (6) skin smooth; (7) supratympanic fold absent; (8) dorsolateral fold absent; (9) webbing formula I 0–1/3 II 0–1 III 0–1 IV 2–0 V; (10) in life, dorsum green with some dark brown spots; (11) flanks with irregular dark markings; (12) head and body with irregular dorsolateral cream stripe; (13) dorsal surface of fore and hind limbs green with dark crossbars; (14) throat, chest and anterior part of belly light-cream with brown dots, posterior part of belly cream.

Description of holotype. Adult female; SVL 48.2 mm; body long (AG/SVL 0.55); head broad and flat (HL/VL 0.33, HW/SVL 0.31, HD/SVL 0.15), longer than wide (HL 16.0 mm, HW 14.9 mm); snout round anteriorly in dorsal view (SE/SVL 0.14), projecting beyond lower jaw; nostril lateral, closer to the eye than to tip of snout (SND 3.1 mm, END 3.3 mm); canthus rostralis distinct; loreal region slightly concave; snout length greater than eye diameter (SE 6.8 mm, ED 5.8 mm); eyes very large (ED/HL 0.36, ED/SE 0.85 mm); pupil horizontally oval; internarial distance wider than interorbital distance and upper eyelid (IND 4.9 mm, IOD 4.8 mm, UEW 3.2 mm); tympanum slightly distinct, round (TD/ED 0.36); vomerine teeth absent; tongue cordiform, notched posteriorly.

Fore limbs robust, FLL/SVL 0.67; relative finger lengths: I<II<IV<III; fingers without webbing; tips of fingers expanded into discs, second to fourth with circummarginal grooves; tip of first finger smaller, without circummarginal groove; width of disc of finger III greater than the diameter of tympanum (TD 2.1 mm, FTD 2.7 mm); subarticular tubercles round, formula 1, 1, 2, 2; inner metatarsal tubercle oval, elongate; outer metatarsal tubercle absent.

Hind limbs long, HLL/SVL 1.71; tibia longer than thigh (FL 23.5 mm, TL 27.8 mm); relative toe length I<II<III<V<IV; tips of toes expanded into discs; width of disc of toe IV narrower than that of finger III; webbing formula I 0 – 1/3 II 0 – 1 III 0 – 1 IV 2 – 0 V; subarticular tubercles oval, formula 1, 1, 2, 3, 2; inner metatarsal tubercle elongate; outer metatarsal tubercle absent.

Skin texture in life: Dorsal surface of head, body and limbs smooth; supratympanic fold absent; dorsolateral fold absent; throat, chest, belly and ventral surface of thigh smooth.

Colouration in life: Dorsal surface of head and back green with some dark brown spots; head and body with a discontinuous dorsolateral cream stripe; side of head and flank green with some dark brown spots on upper part; upper lip green with a thin dark brown longitudinal stripe, the tip of snout cream; iris black, edged in white; tympanum dark brown; dorsal surface of fore and hind limbs green with dark crossbars; throat, chest and anterior part of belly light cream with brown dots; posterior part of belly cream;

RAFFLES BULLETIN OF ZOOLOGY 2019

ventral surface of fore and hind limbs light brown with some greenish spots; toe webbing brown.

Colouration in preservative: Dorsum and flanks brown; head and body with a discontnuous light dorsolateral stripe; upper lip brown with a thin dark stripe; tympanum black; dorsal surface of fore and hind limbs brown with dark crossbars; throat, chest and anterior part of belly light grey with brown dots, posterior part white.

Variation. Measurements and morphological characters of the type series are given in Table 3.

Distribution. Amolops ottorum , new species is currently known only from the type locality in Muong La District, Son La Province, Vietnam ( Fig. 1 ).

Etymology. The species name, ottorum , is the plural possessive form of Mrs Otti Ziegler and Mr Otto Ziegler, who facilitated herpetological research collaborations between Vietnam and Germany. For the common names we suggest Son La Sucker Frog (English) and Ếch bám đá sƠn la (Vietnamese).

Ecological notes. The holotype was collected at 1905 hours on leaves, ca. 1.5 m above the ground and the paratype was collected at 500 hours on a rock nearby a stream. The surrounding habitat was secondary forest of medium and large hardwoods mixed with shrubs ( Fig. 6 ). Air temperature was 17–22°C and relative humidity was 80–85%. Other amphibian species found at the site were Leptobrachium sp., Leptobrachella sp., Quasipaa delacouri (Angel) , Odorrana jingdongensis Fei, Ye & Li , and Kurixalus bisacculus (Taylor) .

Comparisons. We compared the new species with other members of the genus Amolops and data obtained from the literature ( Boulenger, 1899a, b, 1920; Smith, 1923, 1940; Pope, 1929; Andersson, 1939; Liu, 1950; Pope & Romer, 1951; Liu & Hu, 1961, 1975; Jiang, 1983; Wu & Zhao, 1984; Yang, 1991; Ray, 1992; Wu & Tian, 1995; Inger & Chanard, 1997; Inger & Kottelat, 1998; Inger et al., 1999; Liu & Yang, 2000; Liu et al., 2000; Bain et al., 2003, 2006; Bain & Nguyen, 2004; Zhao et al., 2005; Matsui & Nabhitabhata, 2006; Orlov & Ho, 2007; Rao & Wilkinson, 2007; Sengupta et al., 2008; Fei et al., 2009, 2010, 2017; Biju et al., 2010; Stuart et al., 2010; Dever et al., 2012; Sun et al., 2013; Sung et al., 2016; Jiang et al., 2016; Yuan et al., 2018) ( Table 3).

In general appearance, Amolops ottorum , new species is similar to A. granulosus (Liu & Hu) , A. jinjiangensis Su, Yang & Li , A. lifanensis Liu , A. loloensis Liu , A. mantzorum

David, A. tuberodepressus Liu & Yang , and A. xinduqiao Fei, Ye, Wang & Jiang.

Amolops ottorum , new species differs from A. granulosus by having a tympanum visible (vs. indistinct in A. granulosus ), the absence of vomerine teeth (vs. present in A. granulosus ), and different dorsal colour pattern (green with some dark brown spots vs. brown with black spots in A. granulosus ); from A. jinjiangensis by having a tympanum visible (vs. invisible in A. jinjiangensis ), dorsolateral folds absent (vs. present in A. jinjiangensis ), the absence of a pair of large tubercles on sides of cloaca (vs. present in A. jinjiangensis ), and different dorsal colour pattern (green with some dark brown spots vs. light brown or bluish in A. jinjiangensis ); from A. lifanensis by the absence of vomerine teeth (vs. present in A. lifanensis ), having a tympanum visible (vs. invisible in A. lifanensis ), skin smooth (vs. skin with glandular granules in A. lifanensis ), and different dorsal colour pattern (green with some dark brown spots vs. bluish gray to olive brown stippled with black in A. lifanensis ); from A. loloensis by having tympanum visible (vs. invisible in A. loloensis ), flanks smooth (vs. small spinules on flanks in A. loloensis ), dorsal colour pattern (green with some dark brown spots vs. dark green with many large brown spots in A. loloensis ), tibiotarsal articulation reached to the nostril (vs. tibiotarsal articulation reached to the eye in A. loloensis ), a head longer than wide (vs. wider than long or as long as wide in A. loloensis ), and relative finger lengths: I<II<IV<III (vs. I = II<IV<III in A. loloensis ); from A. mantzorum by the absence

gray

life

in

indistinct light brown

colour Brown with spots or

Dorsal Gray-brown, Olive–brown

)

Outer metatarsal tubercle Forelimbs N Y N (

Two oblique vomerine ridges N Y N

Groove disk on first of finger Y N Y

Tympanum Invisible Visible Invisible

Dorsolateral fold N N N

Vocal in sac males N N Y

Head longer wide and HW HL> HW <HL or =HW HL>HW HL

mm

)

Females

52.7 45.2 – 56.6 48.5 – 35.2 39.0 –

(

SVL 45.0 47.5 34.1 Males 37.5 – – 41.2 31.8 –

wuyiensis xinduqiao yunkaiensis

...

A A A

of vomerine teeth (vs. present in A. mantzorum ), different dorsal colour pattern (green with some dark brown spots vs. brown with a few large green blotches in A. mantzorum ), and hind limbs with dark crossbars (vs. without dark crossbars in A. mantzorum ); from A. tuberodepressus by having a tympanum visible (vs. invisible in A. tuberodepressus ), flanks smooth (vs. with flatter tubercles in A. tuberodepressus ), and different dorsal colour pattern (green with some dark brown spots vs. brown with green spots in A. tuberodepressus ); from A. xinduqiao by the absence of vomerine teeth (vs. present in A. xinduqiao ), flanks smooth (vs. with tubercles in A. xinduqiao ), a head longer than wide (vs. head wider than long or length equal to width in A. xinduqiao ), and different dorsal colour pattern (green with some dark brown spots vs. gray-brown, in A. xinduqiao ).

Figures

Fig. 3. Dorsolateral view (A) and ventral view (B) of the female holotype (IEBR 4243) of Amolops ottorum, new species, in life. Photo = A. V. Pham.

Fig. 4. Ventral side of head and chest (A) and foot (B) of the female holotype (IEBR 4243) of Amolops ottorum, new species, in preservative. Photo = A. V. Pham.

Fig. 5. Dorsolateral view of the female paratype (TBU 06) of Amolops ottorum, new species, in life. Photo = A. V. Pham.

Fig. 2. Phylogram based on the partitioned Bayesian analysis. Number above and below branches are MP/ML bootstrap values and combined Bayesian/partitioned Bayesian posterior probabilities (>50% or 0.5), respectively. Asterisk and dash represent 100% (1.0) and <50 % (0.5) values, respectively. The results from the partitioned ML analysis were very similar to those from the combined ML analysis and not presented (see Supplementary Material).

Fig. 1. Map of sampling site in Son La Province, Vietnam: Muong La District (black square), the type locality of Amolops ottorum, new species.

Fig. 6. Habitat of Amolops ottorum, new species, in Ngoc Chien Commune, Muong La District, Son La Province, Vietnam. Photo = N. B. Song.