Tylototriton podichthys, Phimmachak, Somphouthone, Aowphol, Anchalee & Stuart, Bryan L., 2015

Phimmachak, Somphouthone, Aowphol, Anchalee & Stuart, Bryan L., 2015, Morphological and molecular variation in Tylototriton (Caudata: Salamandridae) in Laos, with description of a new species, Zootaxa 4006 (2), pp. 285-310 : 301-303

Tylototriton podichthys sp. nov.

( Fig. 6 )

Tylototriton shanjing Matsui 2013: 187 ; Nishikawa, Khonsue, Pomchote & Matsui 2013a: 264 (part); Sparreboom 2014: 370 (part).

Tylototriton verrucosus verrucosus (part) Le, Nguyen, Nishikawa, Nguyen, Pham, Matsui, Bernardes & Nguyen 2015: 39.

Holotype: NCSM 77721 (field tag BLS 12909), adult female, Laos, Luang Phabang Province, Phoukhoun District, Nam Madao Village, 19º18’0.3”N 102º34’25.2”E, 1,189 m elev., coll. 17 August 2009 by Somphouthone Phimmachak.

Paratypes: NCSM 77722–23 (two females), NCSM 77724–26 (three males), same data as holotype. NUOL 0 0 393 (one male), same data as holotype except 19º16’59.9”N 102º34’41.6”E, 1,287 m elev., coll. 8 June 2009. NUOL 00395–97 (three males), same data as holotype except 19º18’06.8”N 102º34’24.8”E, 1,287 m elev., 8–10 June 2009. NCSM 82935 (one female), same data as holotype except 19.30189ºN 102.57356ºE, 1,287 m elev., coll. 10 July 2012.

NCSM 82939–40, NUOL 00402–03, NUOL 0 0 411 (five females), NCSM 82941–43, NUOL 00409–10, NUOL 0 0 438, (six males), Laos, Xieng Khouang Province, Kham District, Yord Lieng Village, Mor Stream, 19.83986ºN 103.70425ºE, 1,481 m elev., coll. 13 June 2011 by Somphouthone Phimmachak. NUOL 0 0 436, NUOL 0 0 445 (two females), NUOL 0 0 435, NUOL 0 0 444 (two males), Laos, Xieng Khouang Province, Kham District, Yord Lieng Village, Mor Stream, 19.83972ºN 103.70259ºE, 1,493 m elev., coll. 6 July 2012 by Somphouthone Phimmachak.

NCSM 82936, NUOL 0 0 412 (two females), Laos, Huaphanh Province, Viengthong District, Phou Louey National Protected Area, Sakok Village, headwaters of Nam Long Stream, 20.22556ºN 103.23122ºE, 1,348 m elev., coll. 16–17 June 2011 by Somphouthone Phimmachak. NCSM 82937–38 (two males), Laos, Huaphanh Province, Viengthong District, Phou Louey National Protected Area, Sakok Village, headwaters of Nam Long Stream, 21.22669ºN 104.23606ºE, 1,303 m elev., coll. 18 June 2011 by Somphouthone Phimmachak. NUOL 0 0 413 (one male), Laos, Huaphanh Province, Viengthong District, Phou Louey National Protected Area, Sakok Village, headwaters of Nam Long Stream, 21.23153ºN 104.23050ºE, 1,317 m elev., coll. 17 June 2011 by Somphouthone Phimmachak.

Referred material. NCSM 82933 (22 larvae), same data as NUOL 0 0 435 except 22 August 2012. NCSM 82934 (nine larvae), NUOL 0 0 450 (larvae, number of individuals not recorded), same data as NCSM 82939 except coll. 13–16 October 2010 by Somphouthone Phimmachak and Sengvilay Seateun.

NUOL 00406–08, NUOL 0 0 414 (four metamorphs), same data as NUOL 0 0 435 except coll. 10 December 2012.

NUOL 0 0 394 (one eft), same data as NUOL 0 0 395. NCSM 82944–46, NUOL 00439–42 (seven efts), same data as NCSM 82939. NCSM 82948–51 (four efts), same data as NUOL 0 0 435 except coll. 13–16 December 2012. NCSM 82947 (one eft), same data as NCSM 82937. NUOL 0 0 446 (one eft), same data as NUOL 0 0 413.

Subgenus: The new species is assigned to the subgenus Tylototriton Dubois & Raffaëlli 2009 (= T. verrucosus species group of Fei et al. 2005) based on its phylogenetic position ( Fig. 1 ) and having orange coloration on limbs and lateral surfaces of tail ( Nishikawa et al. 2014).

Etymology. The specific epithet is a noun in apposition taken from pod Gr., foot, and ichthys Gr., fish, in reference to the Lao language name pa theen, meaning “fish with feet,” that is widely used for newts ( Tylototriton and Laotriton ) in Laos.

Diagnosis. Tylototriton podichthys sp. nov. is a Tylototriton (subgenus Tylototriton ) having the combination of an indistinct glandular ridge on midline of crown; distinct, rounded rib nodules with diameter equivalent to or greater than that of eye; parotoid oriented parallel to body axis in lateral view; thick, glandular, vertebral tubercular ridge; rough, glandular skin on cranial crest; uniformly orange cranial crest and parotoids; orange markings separated between rib nodules; dark coloration on ventral surfaces of limbs; and dark coloration on digit tips.

Description of holotype. Habitus stout. Head narrower than body, longer than wide, slightly sloping in profile. Snout short, rounded in dorsal view, slightly rounded in profile, exceeding beyond lower jaw. Nostrils close to snout tip, visible from above. Vomeropalatine tooth series in an inverted, narrow V-shape, anteriorly in contact and reaching choanae. Tongue oval, attached at anterior floor of mouth. Gular fold present. Indistinct glandular ridge on midline of crown from level of center of eye to level of corner of mouth. Strong glandular cranial crest on outer margin of crown from level of nostril, weakly curved medially at posterior end, continuous with parotoid. Parotoids enlarged, projecting posteriorly, oriented parallel to body axis in lateral view. Strong vertebral tubercular ridge from posterior end of crown to dorsal margin of tail, visible on anterior one-third of tail, weakly separated from ridge on midline of crown. Dorsolateral row of large glandular warts (rib nodules) on each side from level of axilla to anterior one-third of tail, 16 on left and 15 on right between axilla and level of posterior margin of vent, distinctly knob-like anteriorly, becoming smaller posteriorly, third on both sides the largest. Smaller, glandular warts on most of remaining dorsal and ventral surfaces, warts on crown, nape, and ventrolateral region with clusters of glands, those on throat, tail, and ventral surfaces of limbs granular, those on belly arranged in striations perpendicular to body axis, with a smooth, glandular, ovoid patch of skin on chest. Four fingers, five toes, all without webbing. Tail laterally compressed, tapering posteriorly, narrow dorsal fin, smooth ventral ridge, tip rounded in profile.

Color of holotype in life. Dorsal surface of body, nape, and lores black. Throat, chest, belly, and ventral surfaces of limbs black with limited, irregular orange mottling. Remainder of head, parotoids, vertebral ridge, rib nodules, ventral margin of lower jaw, dorsal surfaces of limbs, ventral surfaces of hands and feet, cloaca, and tail orange, with brightest orange on parotoids, vertebral ridge and rib nodules. Tips of all digits dark brown. Iris brown, pupil black.

Color of holotype in preservative. Orange faded to beige or brown.

Variation. Some paratypes (e.g., females NCSM 82939–40, male NCSM 82943) have much darker orange coloration in life and preservative than holotype ( Fig. 6 C). Some paratypes have dorsolateral rows of rib nodules extending only to base of tail. Some paratypes have truncate snout in dorsal view. Females are heavier, have a more robust body, longer body (SVLA, SVLP, TTL), and shorter vent slits than males (Phimmachak et al., in press). Tail tip acuminate rather than rounded in profile in some paratypes. Measurements of adults are summarized in Table 7 .

Distribution and natural history. Tylototriton podichthys sp. nov. is currently known only from Luang Phabang, Xieng Khouang and Huaphanh Provinces, Laos, from 1,189–1,493 m elevation ( Fig. 3 ). A reported locality of Phu Pan, Xam Neua (Matsui 2013; Nishikawa et al. 2013a; Le et al. 2015) is also in Huaphanh Province. A reported locality of Nam Lieng ( Sparreboom 2014) is the same as the paratype locality in Kham District, Xieng Khouang Province, Laos. Sparreboom (2014) provided a photograph of habitat in Xieng Khouang Province. The natural history and general ecology of the new species is extensively reviewed in Phimmachak et al. (in press).

Comparisons. Tylototriton podichthys sp. nov. differs from all species in the T. asperrimus group (subgenus Yaotriton) by having orange coloration on limbs and lateral surfaces of tail.

The new species is less readily differentiated from some co-members of the T. verrucosus group (subgenus Tylototriton ; Figs. 7–9 ). Tylototriton podichthys sp. nov. differs from T. anguliceps by having an indistinct glandular ridge on midline of crown (distinct ridge on midline of crown in anguliceps ) and by having more robust males (males distinctly slimmer in anguliceps ). Tylototriton podichthys sp. nov. differs from T. kweichowensis and T. pseudoverrucosus by having separated orange markings on rib nodules (orange markings connected, forming continuous dorsolateral lines from parotoid to tail in kweichowensis and pseudoverrucosus ). Tylototriton podichthys sp. nov. differs from T. shanjing by having an indistinct glandular ridge on midline of crown (distinct ridge on midline of crown in shanjing ), no sharp contrast between orange crown and black nape (sharp contrast in shanjing ), dark coloration on ventral surfaces of limbs (orange coloration on ventral surfaces of limbs in shanjing ), and dark digits tips (uniformly orange digit tips in shanjing ). Tylototriton podichthys sp. nov. differs from T. shanorum by having large, rounded rib nodules with diameter equivalent to or greater than that of eye (small, slightly elongated rib nodules with diameter less than that of eye in shanorum ), and by having a thick, glandular, vertebral tubercular ridge (distinctly narrower and less glandular in shanorum ). Tylototriton podichthys sp. nov. differs from T. taliangensis by having rib nodules (absent in taliangensis ) and orange coloration on body (orange coloration limited to parotoid, digit tips, vent, and ventral surface of tail in taliangensis ). Tylototriton podichthys sp. nov. differs from T. uyenoi by having males with shorter heads (HL 16.9–21.3, n =18, in podichthys ; HL 19.1– 25.5, n =7, in uyenoi ; Wilcoxon test, Z=-2.058, p<0.05), by having males with narrower heads (HW 12.8–17.4, n =18, in podichthys ; HW 16.0–19.6, n =7, in uyenoi ; Wilcoxon test, Z=-3.571, p<0.0001), by having an indistinct glandular ridge on midline of crown (distinct ridge on midline of crown in uyenoi ), and having the parotoid oriented parallel to body axis in lateral view (parotoid oriented obliquely downward relative to body axis in lateral view in uyenoi ). Tylototriton podichthys sp. nov. differs from T. verrucosus by having distinctly contrasting coloration between body and the cranial crest, parotoids, vertebral ridge and rib nodules (indistinct contrasting coloration in verrucosus ), by having an indistinct glandular ridge on midline of crown (distinct ridge on midline of crown in verrucosus ), rough, glandular skin on cranial crest (smooth in verrucosus ), and parotoid oriented parallel to body axis in lateral view (parotoid oriented obliquely downward relative to body axis in lateral view in verrucosus ). Tylototriton podichthys sp. nov. differs from T. yangi by having uniformly orange cranial crest and parotoids (orange coloration restricted to posterior margin of cranial ridge and parotoids in yangi ).

Figures

FIGURE 1. Fifty percent majority-rule consensus phylogram resulting from partitioned Bayesian analysis of 3,121 aligned characters of mitochondrial DNA (part of the 16 S rRNA gene, the complete tRNA Leu, ND 1, tRNA Ile, tRNA Gln, tRNA Met, ND 2, tRNA Trp, tRNA Ala, tRNA Asn, tRNA Cys, and tRNA Tyr genes, and part of the COI gene) of Tylototriton and outgroups. Numbers at nodes are Bayesian posterior probabilities. Asterisks (*) indicate nodes with posterior probabilities ≥ 0.99. Numbers at branch tips refer to ID in Table 1.

FIGURE 3. Geographic distributions of the four Tylototriton species known to occur in Laos: T. notialis (circle); T. anguliceps (asterisk); T. panhai (square); and T. podichthys sp. nov. (triangle).

FIGURE 6. Tylototriton podichthys sp. nov.: (A) Dorsal view and (B) ventral view of holotype female (NCSM 77721) in life, (C) dorsal view of female paratype (NCSM 82939) in life, (D) dorsal view of eft (NUOL 00394) in situ, with two human finger tips for scale, (E) habitat at holotype locality in Nam Madao Village, Phoukhoun District, Luang Phabang Province, Laos, and (F) habitat at paratype locality in Yord Lieng Village, Kham District, Xieng Khouang Province, Laos.

FIGURE 7. Dorsal and lateral views of heads of subgenus Tylototriton in preservative. (A – B) Tylototriton podichthys sp. nov. holotype female (NCSM 77721). (C – D) Tylototriton shanjing topotype female (MVZ 219763). (E – F) Tylototriton verrucosus topotype male (UMMZ 189648). (G – H) Tylototriton anguliceps male (NCSM 82953). (I – J) Tylototriton shanorum topotype female (CAS 230899).

FIGURE 8. Dorsal and ventral views of subgenus Tylototriton in preservative. (A – B) Tylototriton podichthys sp. nov. holotype female (NCSM 77721). (C – D) Tylototriton shanjing topotype female (MVZ 219763). (E – F) Tylototriton verrucosus topotype male (UMMZ 189648). (G – H) Tylototriton anguliceps male (NCSM 82953). (I – J) Tylototriton shanorum topotype female (CAS 230899).

FIGURE 9. (A) Dorsal views and (B) ventral views in preservative, left to right, of Tylototriton verrucosus topotype female (UTA 27558), T. podichthys sp. nov. holotype female (NCSM 77721), T. shanorum topotype female (CAS 230899), and T. shanjing topotype female (MVZ 219763). (C) Dorsal views of males in preservative, left to right, of T. anguliceps (NCSM 82953), T. anguliceps (NCSM 82952), T. podichthys sp. nov. (NCSM 77724), and T. podichthys sp. nov. (NCSM 82943). (D) Dorsolateral views in preservative of T. shanorum topotype female (CAS 230899) above, and T. podichthys sp. nov. holotype female (NCSM 77721) below.

Tables

TABLE 7. Measurements (mm) of adult Tylototriton podichthys sp. nov. Abbreviations defined in the text.

Measurement SVLA	Holotype female All type females (n =1) Range; Mean ± SD (n =13) 73.5 59.8–84.5; 70.9 ± 6.7	Paratype males Range; Mean ± SD (n =18) 53.9–72.2; 60.8 ± 4.6
SVLP	80.0 64.4–87.9; 75.5 ± 6.6	58.0–77.8; 66.9 ± 5.0
TAL	63.0 57.2–77.4; 65.0 ± 7.0	51.2–70.4; 60.2 ± 5.9
TTL	143.0 123.9–165.3; 140.4 ± 12.6	117.0–143.1; 127.1 ± 9.5
AXGR	40.6 29.2–45.2; 37.1 ± 4.6	25.4–38.6; 31.0 ± 3.4
TAD	9.7 6.2–9.7; 7.9 ± 0.8	6.1–9.1; 7.2 ± 0.8
HL	21.2 19.1–23.6; 20.7 ± 1.2	16.9–21.3; 19.1 ± 1.3
HW	16.5 14.5–17.7; 16.3 ± 1.0	12.8–17.4; 14.5 ± 1.1
EN	4.3 3.9–5.2; 4.4 ± 0.4	3.6–5.1; 4.1 ± 0.4
IN	4.8 4.1–5.5; 4.9 ± 0.4	3.2–5.2; 4.5 ± 0.5
AL	25.3 22.0–26.9; 25.2 ± 1.6	20.9–26.5; 23.3 ± 1.8
PL	23.6 21.4–28.6; 24.7 ± 2.0	20.0–27.5; 22.7 ± 1.9