Leptobrachella graminicola, Nguyen & Tapley & Nguyen & Luong & Rowley, 2021

Nguyen, Luan Thanh, Tapley, Benjamin, Nguyen, Chung Thanh, Luong, Hao Van & Rowley, Jodi J. L., 2021, A new species of Leptobrachella (Anura, Megophryidae) from Mount Pu Ta Leng northwest Vietnam, Zootaxa 5016 (3), pp. 301-332 : 308-326

Leptobrachella graminicola sp. nov.

Figs. 3–5 & 7–8

Holotype: VNMN 010904 (field tag Fan119), adult male on grass 0.1 m from ground, 1 m from 2–3 m wide rocky stream in evergreen broadleaf forest, Mount Pu Ta Leng , Bat Xat Nature Reserve, Lao Cai Province, Vietnam (N22.40751° E103.60984°; 2386 m elevation, Fig. 2 & 6 ). Collected at night on 04 October 2019, 21:11h by Luan Thanh Nguyen, Luong Van Nong, and Tam Van Ha.

Paratypes: Ten specimens, all collected at night in the same 2–3 m wide rocky stream in evergreen broadleaf forest on Mount Pu Ta Leng, Bat Xat Nature Reserve, Lao Cai Province, Vietnam by Luan Thanh Nguyen, Luong Van Nong, and Tam Van Ha : VNMN 010910 (field tag Fan 117) , VNMN 010909 (field tag Fan 118) adult females on the blade of a sedge-like plant 0.1 m from ground, 1 m from stream, collection details the same as the holotype ; VNMN 010905 (field tag Fan 120) adult male and VNMN 010907 (field tag Fan 124) adult females on the blade of a sedge-like plant 0.1–0.2 m from ground, middle of stream (N22.40787° E103.60900°; 2048 m elevation), collected on 04 October 2019 ; VNMN 010906 (field tag Fan 126) adult male on the blade of a sedge-like plant 0.2 m from ground, nearby stream (N22.40820° E103.60934°; 2400 m elevation), collected on 04 October 2019 ; VNMN 010913 (field tag Fan 128) adult female on the blade of a sedge-like plant 0.2 m from ground nearby stream (N22.40780° E103.60925°; 2405 m), collected on 04 October 2019 ; VNMN 010912 (field tag Fan 166) and VNMN 010914 (field tag Fan 172) two adult males and VNMN 010908 (field tag Fan 170) adult female on the blade of a sedge-like plant 0.1–0.4 m from ground, nearby stream (N22.40700° E103.61219°; 2343 m), all collected on 05 October 2019 .

Referred specimens: HLNP 20191005 00017 male on the blade of a sedge-like plant 0.1–0.4 m from ground, nearby stream (N22.40700° E103.61219°; 2343 m), collected on 05 October 2019. This specimen is not included in the type series due to it being deposited in a local collection. Its taxonomic identity is not in question .

Etymology: Specific epithet “ graminicola ” is a noun in apposition, composed from Latin gramineus (grass) and incola (inhabitant) as all individuals were encountered on graminoid plants with grass-like morphology.

Suggested vernacular name: Mount Pu Ta Leng leaf-litter frog (English), Cóc mày lá cỏ (Vietnamese).

Diagnosis: Assigned to the genus Leptobrachella on the basis of the following characters: small size, presence of macroglands on body (including supra–axillary, pectoral, femoral and ventrolateral glands), the absence of vomerine teeth, the presence of tubercles on eyelids, anterior tip of snout with pale vertical bar and fingers free of webbing ( Smith 1925; Dubois 1983; Lathrop et al. 1998; Delorme et al. 2006). Leptobrachella graminicola sp. nov. is distinguished from its congeners by a combination of: (1) a body size range of 23.1–24.6 mm in six adult males and 28.6–32.9 mm in five adult females; (2) skin on dorsum smooth, with many tubercles and lacking dermal ridges; (3) toes with rudimentary webbing and broad lateral fringes; (4) belly white with brown spots; (5) throat dark brown with light grey-brown flecks and spots; (6) a row of large white spots on the outer edge of the tarsus extending from the heel to the inner metatarsal tubercle, sometimes forming a long white stripe; and (7) a bicoloured iris.

Description of holotype: Head length greater than head width; snout truncate in dorsal and lateral view, protruding slightly beyond margin of lower jaw; distance from nostril to eye subequal to nostril to snout; canthus rostralis distinct; lores sloping; pupil vertical; eye diameter greater than snout length; tympanum distinct, round, diameter half the diameter of eye; tympanic rim slightly elevated; vomerine teeth absent; pineal ocellus absent; vocal sac openings small, located posterolaterally on floor of mouth; tongue wide with broad, shallow notch at posterior tip; supratympanic ridge broad and distinct, running from posterior edge of eye to axillary gland. Tips of fingers rounded, very slightly swollen; relative finger lengths I <II <IV <III; nuptial pads absent; subarticular tubercle present at the base of finger IV, absent on finger I, II and III; large, round inner palmar tubercle present, distinctly separated from small, outer palmar tubercle; fingers without interdigital webbing and lateral fringes. Tips of toes rounded, very slightly swollen; relative toe length I <II <V <III <IV; subarticular tubercles absent; oval shaped inner metatarsal tubercle present, outer metatarsal tubercle absent; interdigital toe webbing rudimentary; distinct and wide lateral fringes on toes II, III, IV and V. Tibia 48.8% of snout to vent length; tibiotarsal articulation reaching to anterior edge of eye. Small tubercles on upper eyelid and on dorsal surfaces of body, forearms and hindlimbs; small tubercles present on throat becoming larger and more dense along the outer margin of the lower jaw; skin on dorsum smooth, with many tubercles; dermal ridges absent; one pair of large round tubercles on the dorsal surface, one on either side of vent; ventral skin smooth; pectoral gland oval, 1.7 mm maximum diameter; femoral gland oval, approximately 1.3 mm maximum diameter, on posteroventral surface of thigh, closer to knee than to vent; supra–axillary gland oval, raised, 1.1 mm diameter at widest point. Ventrolateral glands present.

Colour of holotype in life: Dorsal surface of body brown with darker brown spots, spots level with the scapula bordered with cream; dark brown interorbital bar; canthus rostralis brown; upper lip light grey with dark brown spots. Tympanum dark brown with light brown flecks in the centre, lower border of tympanum cream; lower half of supratympanic ridge dark brown, upper half reddish-brown. Tubercles on upper eyelid and body reddish-brown; flanks olive green, small light grey tubercles on flanks, large orange-coloured tubercles on the dorsal surface either side of vent; dorsal surfaces of hindlimbs, forelimbs, hands and feet light brown, forearm bicoloured lighter brown on the humerus; tubercles on hind limbs ringed with dark brown. Ventral surface of belly white with very dark blackish brown spots; throat dark brown with light grey-brown flecks and spots, spots becoming denser nearer outer margin of lower jaw; ventral surface of forearms unpigmented; ventral surface of the thighs reddish brown with lighter grey-brown spots, ventral surface of tarsus and shank reddish brown with lighter grey-brown flecks, row of large white spots on the outer edge of the tarsus extending from the heel to the inner metatarsal tubercle ( Fig. 5D ). Supra–axillary gland white, femoral glands white, ventrolateral glands white; iris bicolored, upper half copper with black reticulations, lower half silver with black reticulations.

Colour of holotype in preservative: Dorsum dark grey-brown; dorsal surface of limbs light brown. Ventral surface of throat and forearms cream with dark brown flecks; ventral surfaces of body and hindlimbs cream with dark brown spots. Row of large creamy-white spots on the outer edge of the tarsus extending from the heel to the inner metatarsal tubercle. Palmar aspects of hands cream with brown flecks, fingertips grey. Plantar aspect of feet dark grey-brown with grey finger tips, lateral fringes and webbing. Pectoral glands, femoral glands, supra-axillary glands and ventrolateral glands creamy white.

Variation: VNMN 010910 and VNMN 010909 with several large dark brown spots on the flank; all specimens, except holotype with dark brown transverse bars present on thigh, shank, tarsus, lower arms fingers and toes, those on thigh and shank with orange makings in the centre of each bar. Supra–axillary gland white with orange tip ( VNMN 010910 , VNMN 010909 , VNMN 010913 and HLNP 20191005 00017) . VNMN 010907 , VNMN 010906 , VNMN 010912 and VNMN 010914 with three pairs of large round, orange-coloured tubercles on the dorsal surface (three tubercles on either side of vent), all other specimens with one pair of orange tubercles, one on either side of the vent. The row of large creamy-white spots on the outer edge of the tarsus joined to form a white stripe extending from the heel to the inner metatarsal tubercle in VNMN 010912 , HLNP 20191005 00017 and VNMN 010908 . See Table 2 for measurements of all individuals in the type series.

Natural history: All specimens of Leptobrachella graminicola sp. nov. were associated with disturbed evergreen broadleaf forest with a relatively open canopy of bamboo ( Fig. 6 ). All individuals were encountered at night from 19:00–22:00h in October 2019 and observed on sedge-like plants found growing alongside or in the middle of 2–3 m wide streams. The streams were clear, shallow and with a rocky bed. Males were sometimes found in close proximity to each other on the sedge-like plants ( Fig. 6C ). During the surveys, males were not heard calling although all females of this species observed were gravid. There was no rain during surveys and the air temperature ranged from 12.8–13.2°C at night. Tadpoles were not observed. Within the genus Leptobrachella , Leptobrachella graminicola sp. nov. is syntopic with L. bourreti . Within Megophryidae , the new species is syntopic with Megophrys gigantica ( Liu, Hu, and Yang 1960) , M. frigida Tapley, Cutajar, Nguyen, Portway, Mahony, Nguyen, Harding, Luong and Rowley, 2021 and Leptobrachium ailaonicum ( Yang, Chen, and Ma, 1983) . The presence of gravid females and presence of multiple males on the blades of the sedge-like plants in the middle of the stream indicates that the breeding season could be October.

Distribution and conservation status: This species is only known from the recently designated Bat Xat Nature Reserve on Mount Pu Ta Leng at elevations between 2383 and 2437 m asl ( Fig. 2 ). The site where Leptobrachella graminicola sp. nov. is found faces the immediate threat of habitat loss and the activities of tourists. Leptobrachella graminicola sp. nov. was not encountered during other surveys on Mount Pu Ta Leng at different times of year and at different elevations (October 2019, 1568 m elevation on the same side of the mountain, 1.7 km in a straight line from the collection site; April 2018 and October 2019, 2300 m elevation on the opposite side of the mountain, 2.2 km straight line from the collection site; April 2018 and October 2019, 1900 m elevation at the on the opposite side of the mountain, 3.7 km straight line from the collection site). Most species of Leptobrachella are associated with forests and it is likely that they are forest dependent. Lao Cai Province has been subject to some of the most intense levels of forest degradation and deforestation in Vietnam ( Khuc et al. 2018). Leptobrachella graminicola sp. nov. likely qualifies for being assessed as Data Deficient in accordance with the IUCN Red List of Threatened Species categories and criteria (see IUCN 2012).

Comparisons: Leptobrachella graminicola sp. nov. can be distinguished from all reported Leptobrachella from Asia north of the Isthmus of Kra on the basis of morphology. Comparisons with each species can be seen in Table 3. The following comparison is based on six male and five female Leptobrachella graminicola sp. nov.

......continued on the next page

Species SVL male SVL female Interdigital Lateral Belly pattern Dorsal skin texture Bicolored Reference toe webbing fringes iris on toes

Leptobrachella 23.1–24.6 28.6–32.9 Rudimentary Wide White with very dark blackish Smooth, with many tuber- Yes This study graminicola (N=6) (N=5) brown spots cles and lacking dermal

sp. nov. ridges

L. aerea 25.1–28.9 27.1–38.6 Rudimentary Narrow Nearly immaculate creamy white, Finely tuberculate No Rowley et al. 2010a (N=28) (N=12) brown speckling on margins

L. alpina 24.0–26.4 31.7–32.5 Rudimentary Wide Creamy white with dark spots Relatively smooth, some No Ohler et al. 2011;

(in males) with small warts Wang et al. 2020 L. applebyi 19.6–20.8 21.7 (N=1) Rudimentary Absent White with dark speckling or Smooth No Rowley & Cao,

(N = 5) brown with white speckling 2009

L. ardens 21.3–24.7 25.4 (N=1) Absent Absent Reddish brown with white speck- Smooth – finely sha- No Rowley et al. 2016 (N=15) ling greened

L. aspera 22.4 (N=1) 25.0–26.4 Rudimentary Narrow Creamy white with distinct dark Rough with dense conical Yes Wang et al. 2020

(N=3) spots granules, tubercles, and dermal ridges

L. bashaensis 22.9–25.6 27.1 Rudimentary Narrow Off-white with dark spots Shagreened with small Yes Lyu et al. 2020

(N=6) (N=1) tubercles

L. bidoupensis 23.6–24.6 29.2–29.4 Rudimentary Narrow Reddish brown with white speck- Smooth Yes Rowley et al. 2011 (N=4) (N=2) ling or marbling

L. bijie 29.0–30.4 Unknown Rudimentary Narrow White with distinct nebulous grey- Shagreened and granular Yes Wang et al. 2019 (N=8) ish speckling with short longitudinal dermal ridges

L. botsfordi 29.1–32.6 30.0–31.8 Rudimentary Narrow Reddish brown with white speck- Shagreened No Rowley et al. 2013 (N=7) (N=2) ling

L. bourreti 27.4–36.2 39.5–45.0 Rudimentary Narrow Creamy white, light yellow and Relatively smooth, some Yes Bourret, 1937; (N=26) (N=7) orange in some specimens. with small warts Ohler et al. 2011; this study

......continued on the next page

Species SVL male SVL female Interdigital Lateral Belly pattern Dorsal skin texture Bicolored Reference toe webbing fringes iris on toes

L. chishuiensis 30.8–33.4 34.2 Rudimentary Narrow White with grey speckling on Shagreened and granular Yes Li et al. 2020

(N=7) (N=1) margins

L. crocea 22.2–27.3 Unknown Rudimentary Absent Bright orange Highly tuberculate No Rowley et al. 2010b (N=16)

L. dorsospina 28.7–30.5 32.1–39.8 Rudimentary Narrow Greyish white with dark spots Rough with dense conical Yes Wang et al. 2020 (N=2) (N=5) granules, tubercles, dermal ridges, and conical spines

L. eos 33.1–34.7 40.7 (N=1) Rudimentary Wide Creamy white Shagreened Yes Ohler et al. 2011 (N=6)

L. feii 21.51–22.75 25.67 Rudimentary Narrow Creamy white with small dark Shagreened with small Yes Chen et al. 2020 (N=5) (N=1) spots tubercles and unequal dermal ridges

L. firthi 26.4–29.2 25.7–36.9 Rudimentary Wide Creamy white Shagreened Variable Rowley et al. 2012 (N=21) (N=14)

L. flaviglandulosa 23.0–27.0 29.3 (N=1) Rudimentary Narrow White with black speckling Shagreened with yellowish Yes Chen et al. 2020 (N=13) brown tubercles

L. fuliginosa 28.2–30.0 Unknown Rudimentary Narrow White with brown speckling Nearly smooth, few tuber- Yes Matsui, 2006

(N=4) cles

L. isos 23.7–27.9 28.6–31.5 Rudimentary Wide Creamy white with white dusting Mostly smooth, females Yes Rowley et al. 2015a (N=38) (N=9) on margins more tuberculate

L. jinshaensis 29.7–31.2 Unknown Absent Narrow Creamy white Shagreened, some of the Yes Cheng et al. 2021 (N=5) granules forming longitudinal short skin ridges

L. kalonensis 25.8–30.6 28.9–30.6 Absent Absent Dark brown with white speckling Smooth Yes Rowley et al. 2016 (N=16) (N=3)

L. khasiorum 24.5–27.3 31.2–33.4 Rudimentary Wide Creamy white Isolated speckled tubercles Yes Das et al. 2010 (N=4) (N=3)

......continued on the next page

Species SVL male SVL female Interdigital Lateral Belly pattern Dorsal skin texture Bicolored Reference toe webbing fringes iris on toes

L. lateralis 26.9–28.25 36.6 Rudimentary Absent Creamy white Rough and granular Unknown Anderson, 1871; (N=NR) (N=NR) Wang et al. 2020

L. laui 24.8–26.7 28.1 (N=1) Rudimentary Wide Creamy white with white dusting Round, granular tubercles No Sung et al. 2014 (N=1) on margins

L. liui 22.5–26.5 24.5–27.8 Rudimentary Wide Creamy white with tiny grey spots Round, granular tubercles, No Ohler et al. 2011; (NR) (NR) dermal ridges present Wang et al. 2020

L. macrops 28.0–29.3 30.3 (N=1) Rudimentary Absent Greyish-violet with some white Dorsal skin roughly granu- Yes Duong et al. 2018 (N=3) speckling lar with larger tubercles

L. maculosa 24.2–26.6 27.0 (N=1) Absent Absent Brown with white speckling Mostly smooth Yes Rowley et al. 2016 (N=3)

L. mangshanensis 22.2–27.8 30.2 (N=1) Rudimentary Narrow Reddish brown with white speck- Nearly smooth, scattered Yes Hou et al. 2018 (N=27) ling tubercles

L.maoershanensis 25.2–30.4 29.1 (N=1) Rudimentary Narrow Creamy white with irregular black Shagreened with small Yes Yuan et al. 2017 (N=8) spots tubercles and longitudinal ridges

L. melanoleuca 26.6–29.0 32.7 Rudimentary Absent Large black spots on a white Skin nearly smooth, scat- Yes Matsui, 2006 (N=11) background tered with small tubercles

L. melica 19.5–22.7 Unknown Rudimentary Absent Pale pink with greyish spots and Smooth No Rowley et al. 2010b (N=7) white speckling

L. minima 25.7–31.4 31.6–37.3 Rudimentary Absent Creamy white Smooth Yes Ohler et al. 2011; (N=46) (N=14) Wang et al. 2020

L. nahangensis 40.8 Unknown Rudimentary Absent Creamy white Smooth No Lathrop et al. 1998 (N=1)

L. namdongensis 30.9 32.1–35.3 Rudimentary Absent Creamy white with brown dusting Finely tuberculate Yes Hoang et al. 2019 (N=1) (N=3) on margins

L. neangi NR 35.4–36.3 Rudimentary Absent Belly transparent, immaculate Dorsal skin with small, ir- No Stuart & Rowley, (N=2) purplish grey in life regular bumps and ridges 2020

......continued on the next page toe webbing fringes iris on toes

L. niveimontis 22.5–23.6 28.5–28.7 Rudimentary Narrow Black and bluish-white marbling Relatively smooth with Yes Chen et al. 2020 (N=5) (N=2) small tubercles

L. nokrekensis 26.0–33.0 34.0–35.0 Rudimentary Unknown Creamy white Tubercles and longitudinal Yes Mathew and Sen, (N=5) (N=2) dermal ridges 2010

L. nyx 26.7–32.6 37.0–41.0 Rudimentary Absent Creamy white, with brown mar- Rounded tubercles Unknown Ohler et al. 2011; (N=7) (N=3) gins Chen et al. 2020

L. oshanensis 26.6–30.7 31.6 (N=1) Absent Absent Whitish with small grey spots Smooth with few dermal Yes Ohler et al. 2011 (N=NR) ridges

L. pallida 24.5–27.7 Unknown Absent Absent Brown with white speckling Tuberculate Yes Rowley et al. 2016 (N=8)

L. pelodytoides 27.5–32.3 Unknown One third Narrow Whitish Small, smooth warts Unknown Chen et al. 2020 (N=NR) webbed

L. petrops 23.6–27.6 30.3–47.0 Absent Narrow White Highly tuberculate Yes Rowley et al. 2017a (N=21) (N=17)

L. pluvialis 21.3–27.52 25.5–33.5 Absent Absent Dirty white with brown marbling Smooth, flattened tubercles Yes Ohler et al. 2000; (N=32) (N=9) or dark spots on flanks This study

L. puhoatensis 24.2–28.1 27.3–31.5 Rudimentary Narrow Deep reddish brown with faint Longitudinal skin ridges Yes Rowley et al. 2017b (N=8) (N=3) white speckling

L. purpuraventra 27.3–29.8 33.0–35.3 Rudimentary Narrow Greyish white with nebulous dark Shagreened and granular Yes Wang et al. 2019 (N=12) (N=4) speckling with dermal ridges

L. purpurus 25.7–27.5 Unknown Rudimentary Wide Dull white with indistinct grey Shagreened with small Yes Yang et al. 2018 (N=2) dusting to dull grey tubercles

L. pyrrhops 30.3–33.9 30.8–34.3 Rudimentary Absent Opaque pinkish to light bluish- Slightly shagreened Yes Poyarkov et al. (N=2) (N=7) purple with bluish-white speckles 2015

L. rowleyae 23.4–25.4 27.0–27.8 Absent Absent Pinkish milk-white to lightly Mostly smooth Yes Nguyen et al. 2018 (N=11) (N=2) brown with numerous white speckles

......continued on the next page

Species SVL male SVL female Interdigital Lateral Belly pattern Dorsal skin texture Bicolored Reference toe webbing fringes iris on toes

L. shangsiensis 24.9–29.4 30.8–35.9 Rudimentary Narrow yellowish creamy-white Mostly smooth with nu- Yes Chen et al. 2019 (N=11) (N=5) merous tiny tubercles

L. suiyangensis 28.7–29.7 30.5–33.5 Rudimentary Narrow Yellowish creamy-white with Shagreened with small Yes Luo et al. 2020 (N=5) (N=3) brown speckling granules

L. sungi 48.3–52.7 56.7–58.9 Rudimentary Narrow White Granular No Lathrop et al. 1998; (N=3) Fei et al. 2012

L. tadungensis 23.5–26.0 32.1 (N=1) Absent Absent Dark brown with fine white Smooth No Rowley et al. 2016 (N=8) speckling

L. tamdil 32.3 (N=1) 32.3 (N=1) Rudimentary Narrow Pale grey Weakly tuberculate Yes Sengupta et al. 2010 L. tengchongensis 23.9–26.0 28.8–28.9 Rudimentary Narrow White with brown spots Longitudinal dermal ridges No Yang et al. 2016 (N=5) (N=2)

L. tuberosa 24.4–29.5 30.2 (N=1) Rudimentary Absent White with small grey spots / Highly tuberculate No Inger et al. 1999 (N=16) streaks

L. ventripunctata 23.7–27.7 31.5–35.0 Rudimentary Absent Creamy white with dark brown Longitudinal dermal ridges Yes Ohler et al. 2011 (N=19) (N=2) spots

L. wuhuangmontis 25.6–30.0 33.0–36.0 Rudimentary Narrow Greyish white with tiny white and Rough, scattered with Yes Wang et al. 2018 (N=9) (N=4) black spots dense conical tubercles

L. wulingensis 24.5–32.8 29.9–38.5 Rudimentary Narrow Creamy white Shagreened with sparse Yes Qian et al. 2020 (N=4) (N=3) large warts, sometimes with longitudinal dermal ridges

L. yeae 25.8–31.2 33.7–34.1 Rudimentary Narrow Cream white with brown specking Relatively smooth with Yes Shi et al. 2021 (N=10) (N=10) on sides and upper abdomen tiny granules

L. yingjiangensis 25.7–27.6 Unknown Rudimentary Wide Creamy white with dark brown Shagreened with small Yes Yang et al. 2018 (N=6) flecks on margin tubercles

L. yunkaiensis 25.9–29.3 34.0–35.3 Rudimentary Wide Pinkish, with brown speckling Shagreened with short skin Yes Wang et al. 2018 (N=6) (N=2) ridges and raised warts

L. zhangyapingi 45.8−52.5 Unknown Rudimentary Wide Creamy white with brown margins Mostly smooth with dis- yes Jiang et al. 2013 (N=7) tinct tubercles

Leptobrachella graminicola sp. nov. is readily distinguished from its closest relative L. bourreti . Leptobrachella graminicola sp. nov. differs from L. bourreti ( Fig. 7 & Table 4) by having a smaller adult male size SVL 23.1–24.6 mm (versus 27.4–36.2 mm, N=26, in L. bourreti ; Ohler et al. 2011; material examined), a smaller adult female size SVL 28.6–32.9 mm (versus 39.5–45.0 mm, N=5, in L. bourreti ; Ohler et al. 2011; material examined), wide lateral fringes on toes (versus narrow in L. bourreti ; Ohler et al. 2011; material examined) and a white ventral surface with brown spots (versus creamy white, yellow or orange in L. bourreti ; Bourret 1937; Ohler et al. 2011; material examined).

Leptobrachella graminicola sp. nov. can be distinguished from other Leptobrachella species known from the Hoang Lien Range. Leptobrachella graminicola sp. nov. differs from L. botsfordi by having a smaller adult male size SVL 23.1–24.6 mm (versus 29.1–32.6 mm, N=7, in L. botsfordi ; Rowley et al. 2013), wide lateral fringes on toes (versus narrow in L. botsfordi ; Rowley et al. 2013), a smooth dorsal surface with many tubercles (versus shagreened dorsal surface in L. botsfordi ; Rowley et al. 2013) and a bicolored iris (versus a brownish gold iris with black reticulations, Rowley et al. 2013); from L. pluvialis ( Fig. 8 & Table 4) by the presence of rudimentary webbing and wide lateral fringes on toes (versus absence of webbing and lateral fringes in L. pluvialis ; Ohler et al. 2000) and dark brown throat with light grey-brown flecks and spots, spots becoming denser nearer outer margin of lower jaw, no large white spots on lower jaw (versus throat white without grey-brown flecks and two white spots on the lower jaw in L. pluvialis ; material examined); from L. sungi by having a smaller adult male size SVL 23.1–24.6 mm (versus 48.3–52.7 mm, N=3, in L. sungi ; Lathrop et al. 1998), a smaller adult female size SVL 28.6–32.9 mm (versus 56.7–58.9 mm, N=3, in L. sungi ; Lathrop et al. 1998), wide lateral fringes on toes (versus narrow in L. sungi ; Lathrop et al. 1998), a white ventral surface with brown spots (versus white ventral surface in L. sungi ; Lathrop et al. 1998), a smooth dorsal surface with many tubercles (versus granular dorsal surface in L. sungi ; Lathrop et al. 1998) and a bicolored iris (versus iridescent gold green iris in L. sungi ; Lathrop et al. 1998) and from L. ventripunctata by having wide lateral fringes on toes (versus absence of lateral fringes on toes in L. ventripunctata ; Ohler et al. 2000) dorsal surface lacking dermal ridges (versus dermal ridges present on the dorsal surface in L. ventripunctata ; Ohler et al. 2000; Yang et al. 2018).

Leptobrachella graminicola sp. nov. differs from other congeneric species north of the Isthmus of Kra by having a white belly with very dark blackish brown spots ( L. aerea , L. chishuensis , L. eos , L. firthi , L. isos , L. jinshaensis , L. khasiorum , L. lateralis , L. laui , L. minima , L. nahangensis , L. namdongensis , L. nokrekensis , L. nyx , L. pelodytoides , L. petrops , L. purpurus , L. tamdil , L. wulingensis , L. yeae , L. yingjiangensis , and L. zhangyapingi have a mostly white, to pale grey belly, with or without dark spots around the margin); L. applebyi has a white belly with dark speckling or brown a brown belly with white speckling; L. ardens ; L. bidoupensis , L. kalonensis , L. maculosa , L. mangshanensis , L. pallida , L. puhoatensis , and L. tadungensis have brown or reddish-brown bellies with white speckling; L. crocea has a bright orange belly; L. shangsiensis and L. suiyangensis have a yellowish, cream-white belly; L. flaviglandulosa and L. fuliginosa have a white belly with black or brown speckling; L. liui , L. oshanensis , and L.tuberosa have a whitish belly with grey spots, L. macrops has a greyish-violet belly with white speckling; L. melica has a pale pink belly with greyish spots and white speckling; L. neangi has a transparent, immaculate purplish grey belly in life; L. wuhuangmontis has a greyish white belly with tiny white and black spots; and L. yunkaiensis has a pinkish belly with brown speckling. Leptobrachella graminicola sp. nov. differs from L. melanoleuca , L. pyrrhops , and L. rowleyae by the presence of wide lateral fringes on toes (lateral fringes are absent in L. melanoleuca , L. pyrrhops and L. rowleyae ). Leptobrachella graminicola sp. nov. differs from L. alpina and L. tengchongensis by the presence of a bicoloured iris which is absent in L. alpina and L. tengchongensis . Leptobrachella graminicola sp. nov. differs from L. aspera , L. bashaensis , and L. feii , by having a larger adult female size SVL 28.6–32.9 mm (versus SVL ≤ 27.1 mm in adult female L. aspera , L. bashaensis and L. feii ; Table 3), and further from L. bashaensis by having a dark brown throat with light grey-brown flecks and spots (versus an off-white throat with faint spots) and further from both L. aspera and L. feii by the absence of dermal ridges on the dorsum (versus presence of unequal dermal ridges on the dorsum of L. feii ; and dermal ridges on the dorsum of L. aspera ). Leptobrachella graminicola sp. nov. differs from L. bijie , L. dorsospina , L. jinshaensis , and L. purpuraventra by having a smaller adult male size SVL 23.1–24.6 mm (versus SVL ≥ 27.3 mm in adult male L. bijie ; L. dorsospina , L. jinshaensis and L. purpuraventra ; Table 3) and further from L. bijie ; L. dorsospina , L. jinshaensis and L. purpuraventra by the absence of dermal ridges on the dorsum (versus presence of dermal ridges on the dorsum of L. bijie , L. dorsospina , L. jinshaensis and L. purpuraventra ; Table 3). Leptobrachella graminicola sp. nov. differs from L. maoershanensis by having a dark brown throat with light grey-brown flecks and spots (versus a creamy white throat which may be immaculate or have irregular black spots) and further from L. maoershanensis by the absence of dermal ridges on the dorsum (versus presence of dermal ridges on the dorsum in L. maoershanensis ). Leptobrachella graminicola sp. nov. differs from in L. niveimontis by having a dark brown throat with small white spots (versus marbled with bluish white and black in L. niveimontis ).

Figures

FIGURE 2. Collection site of Leptobrachella graminicola sp. nov. in the Hoang Lien Range, northwest Vietnam. Blue point represents the collection site. Pale grey areas indicative of higher elevation, dark green indicative of lowest elevation.

FIGURE 3. Dorsolateral view of Leptobrachella graminicola sp. nov. in life (A) adult male holotype VNMN 010904, (B) adult female paratype VNMN 010910, (C) adult female paratype VNMN 010913, (D) adult male paratype VNMN 010906.

FIGURE 4. Leptobrachella graminicola sp. nov. in life under sedation. (A) dorsal view of adult male holotype VNMN 010904, (B) ventral view of adult male holotype VNMN 010904, (C) dorsal view of adult female paratype VNMN 010910, (D) ventral view of adult female paratype VNMN 010910, (E) dorsal view of adult female paratype VNMN 010908, (F) ventral view of adult female paratype VNMN 010908. 10 mm scale bar.

FIGURE 5. Leptobrachella graminicola sp. nov. adult male holotype VNMN 010904 in preservative. (A) Dorsal view, (B) ventral view, (C) palmar surface of right hand, and (D) plantar surface of right foot, black arrows highlight the row of large white spots on the outer edge of the tarsus extending from the heel to the inner metatarsal tubercle. 10 mm scale bar.

FIGURE 6. (A) Macrohabitat of of Leptobrachella graminicola sp. nov. Mount Pu Ta Leng, Bat Xat District, Lao Cai Province, (B) microhabitat of Leptobrachella graminicola sp. nov. Mount Pu Ta Leng, Bat Xat District, Lao Cai Province, and (C) specimens of Leptobrachella graminicola sp. nov. in situ.

FIGURE 7. Ventral surfaces of Leptobrachella graminicola sp. nov. from Bat Xat District compared with Leptobrachella bourreti (A) ventral view of Leptobrachella graminicola sp. nov. adult male holotype VNMN 010904, (B) ventral view of adult male L. bourreti VNMN 010916, (C) ventral view of adult male L. bourreti AMS R.186825 from Sa Pa District, (D) ventral view of adult male L. bourreti HLNP2017 0908 00021 from Bat Xat District, (E) ventral view of adult female L. bourreti AMS R.188515 from Bat Xat District, (F) ventral view of adult female L. bourreti VNMN 10917 from Bat Xat District. 10 mm scale bar.

FIGURE 8. Ventral surfaces of Leptobrachella graminicola sp. nov. from Bat Xat District compared with Leptobrachella pluvialis collected from Sa Pa District (A) ventral view of Leptobrachella graminicola sp. nov. adult male holotype VNMN 010904, (B) ventral view of adult male L. pluvialis VNMN 010918, (C) ventral view of adult male L. pluvialis AMS R.186793 (D), ventral view of adult male L. pluvialis AMS R.186797 and (E) ventral view of adult female L. pluvialis AMS R.186798. 10 mm scale bar.