Diploderma tachengense, Liu & Hou & Ananjeva & Rao, 2023

Liu, Shuo, Hou, Mian, Ananjeva, Natalia B. & Rao, Dingqi, 2023, Four new species of the genus Diploderma Hallowell, 1861 (Squamata, Agamidae) from China, ZooKeys 1148, pp. 167-207 : 167

Diploderma tachengense sp. nov.

Figs 13 , 14 , 15

Type material.

Holotype. KIZ2022028, adult male, collected on 6 July 2022 by Shuo Liu from Kena Village, Tacheng Town, Weixi County, Diqing Prefecture, Yunnan Province, China (27°34'12"N, 99°20'36"E, 2180 m elevation).

Paratypes. KIZ2022027, adult male; KIZ2022029, adult female; KIZ2022038, subadult male; and KIZ2022039, subadult female; collecting information all the same as the holotype.

Etymology.

The specific epithet refers to Tacheng Town, where the new species was discovered.

Diagnosis.

Diploderma tachengense sp. nov. can be diagnosed from congeners by a combination of the following morphological characteristics: (1) body size moderate, SVL 55.2-55.7 mm in adult males, 65.4 mm in adult female; (2) tail moderately long, TAL/SVL 1.88-1.89 in adult males, 1.56 in adult female; (3) limbs moderately long, FLL/SVL 0.45-0.47 in adult males, 0.46 in adult female, HLL/SVL 0.76-0.78 in adult males, 0.70 in adult female; (4) head relatively robust, HW/HL 0.73-0.80 in adult males, 0.74 in adult female; (5) MD 38-44; (6) F4S 15-19, T4S 20-24; (7) tympanum concealed; (8) nuchal and dorsal crests continuous, feebly developed, no skin fold under nuchal and dorsal crests; (9) distinct transverse gular fold present; (10) ventral scales of head homogeneous, feebly keeled; (11) ventral scales of body strongly keeled; (12) gular spot present in both sexes, pale yellow in life; (13) dorsolateral stripes distinct in males, strongly jagged, pale yellow in life; (14) radial stripes around eye relatively distinct; (15) oral cavity and inner lips pinkish white, tongue pink in life.

Description of holotype.

Adult male, SVL 55.2 mm; tail moderately long, TAL 104.5 mm, TAL/SVL 1.89; limbs moderately long, FLL 25.9 mm on left side, FLL/SVL 0.47, HLL 41.7 mm on left, HLL/SVL 0.76. Head relatively robust, HW/HL 0.73, HD/HW 0.87; snout moderately long, SEL/HL 0.36. Rostral elongated, bordered by six small postrostral scales; dorsal head scales heterogeneous, all strongly keeled; distinct Y-shaped ridge on dorsal snout. Nasal oval, separated from first supralabial by single row of scales on each side; loreals small, keeled; suborbital scale rows 4/4, keeled; canthus rostralis elongated, greatly overlapping with each other; enlarged, keeled scales forming distinct single lateral ridge from posteroinferior eye to posterosuperior tympanum on each side; tympanum concealed under scales; SL 9/9, feebly keeled. Mental approximately triangular; IL 10/10; enlarged chin shields 4/4, smooth, first one contacting IL on each side, second ones separated from IL by one row of small scales on each side, remaining ones separated from IL by two rows of small scales on each side; ventral head scales homogeneous in size, feebly keeled; distinct transverse gular fold present; gular pouch weakly developed.

Distinct shoulder fold present; dorsal body scales heterogeneous in size and shape, all keeled, tip pointing backwards; axillary scales much smaller than remaining dorsals; enlarged dorsal scales forming one intermittent longitudinal row between dorsal crest and dorsolateral stripe on each side, remaining enlarged dorsal scales irregularly scattered on each side of body. Nuchal and dorsal crests feebly developed, continuous; no skin fold under nuchal and dorsal crests; MD 43. Dorsal limb scales strongly keeled, mostly homogeneous, except a few enlarged, conical scales on postaxial thighs; F4S 16/17, T4S 21/22. Ventral body scales approximately parallel, homogeneous, all strongly keeled, VN 55. Ventral limb scales parallel, small on upper arms and thighs and larger on forearms and crus, all strongly keeled. Tail scales all strongly keeled, ventral tail scales slightly larger than dorsal tail scales.

Colouration of holotype in life.

Dorsal surface of head dark brown with indistinct transverse bands. Lateral surfaces of head brownish yellow. Upper lips brownish grey, lower lips white. Distinct radial stripes around eye on each side. Oral cavity and inner lips pinkish white, tongue pink.

Dorsal surface of body brownish black. A pale yellow strongly jagged dorsolateral stripe on each side of body from occipital region to pelvis. Several pale yellow spots scattered below dorsolateral stripe on each side of body. Dorsal surfaces of limbs brown. Distinct dark transverse bands present on dorsal surfaces of limbs. Dorsal surface of tail brown with indistinct dark transverse bands.

Ventral surface of head white. A pale yellow gular spot present on posterior central part of ventral head, indistinct dark stripes on other parts of ventral head. Ventral surface of body white with no pattern, ventral surfaces of limbs and tail reddish white.

Variations.

The variations of metrical characteristics of the type series are provided in Table 5 . Other variations are as follows: the dorsal colour is paler, there are some dark inverted triangular patterns between the two dorsolateral stripes, the radial stripes around eyes are more indistinct, and the dark stripes on ventral head are more distinct in all paratypes; in addition, the dorsolateral stripes are indistinct, yellowish white in the female paratypes.

Comparisons.

Diploderma tachengense sp. nov. differs from D. brevipes , D. chapaense , D. fasciatum , D. hamptoni , D. luei , D. makii , D. menghaiense , D. micangshanense , D. ngoclinense , D. polygonatum , D. swinhonis , and D. yunnanense by the presence of a transverse gular fold (vs. absence).

Diploderma tachengense sp. nov. differs from D. dymondi , D. panlong , D. slowinskii , D. varcoae , and D. swild by having concealed tympana (vs. exposed).

Diploderma tachengense sp. nov. differs from D. drukdaypo , D. flaviceps , D. shuoquense , D. splendidum , and D. vela by the presence of a distinct gular spot in males in life (vs. absence).

Diploderma tachengense sp. nov. differs from D. batangense , D. bowoense , D. brevicauda , D. daochengense , D. flavilabre , D. formosgulae , D. iadinum , D. laeviventre , D. limingensis , D. xinlongense , D. yangi , D. yongshengense , D. yulongense , and D. zhaoermii by having a pale yellow gular spot in males in life (vs. chartreuse, blue, green, lilac, orange, or yellowish white).

Diploderma tachengense sp. nov. differs from D. angustelinea by wide strongly jagged dorsolateral stripes in males (vs. narrow, feebly jagged); D. grahami by having relatively longer hind limbs (HLL/SVL 0.70-0.78 vs. 0.61), having a distinct transverse gular fold (vs. feeble), and the presence of dorsolateral stripes (vs. absence); from D. kangdingense by the absence of skin folds under nuchal and dorsal crests in males (vs. presence), and having white ventrolateral surface of body in males in life (vs. yellow); from D. panchi by having relatively longer hind limbs in females (HLL/SVL 0.70 vs. 0.60-0.66), the presence of a distinct gular spot in females in life (vs. absence), and the presence of black stripes on ventral head (vs. absence); and from D. qilin by having a relatively shorter tail (TAL/SVL 1.88-1.89 vs. 2.01-2.18 in males, 1.56 vs. 1.74-2.00 in females) and having a pink tongue (vs. pale flesh coloured).

Diploderma tachengense sp. nov. is phylogenetically sister to D. aorun ; however, Diploderma tachengense sp. nov. can be differentiated from the latter by having a pale yellow gular spot in both sexes in life (vs. blue in both sexes), having a relatively much shorter tail (TAL/SVL 1.88-1.89 vs. 2.12-2.21 in males, 1.56 vs. 1.91-2.08 in females), having a greater ratio of head width to head length (HW/HL 0.73-0.80 vs. 0.68-0.73 in males, 0.74 vs. 0.67-0.70 in females), and the absence of skin folds under nuchal and dorsal crests in males (vs. presence).

Diploderma tachengense sp. nov. differs from Diploderma danbaense sp. nov. by the presence of a distinct gular spot in both sexes in life (vs. absence), the presence of distinct radial stripes around eyes (vs. absence), the absence of distinct, dark, hollow, approximately rhomboid patterns between dorsolateral stripes on dorsum (vs. absence), and the absence of skin folds under nuchal and dorsal crests in males (vs. presence).

Diploderma tachengense sp. nov. differs from Diploderma donglangense sp. nov. by having vermiculate stripes on ventral head (vs. short black stripes), having strongly jagged dorsolateral stripes in males (vs. moderately jagged), and the presence of distinct radial stripes around eyes (vs. absence).

Diploderma tachengense sp. nov. differs from Diploderma jiulongense sp. nov. by having a relatively shorter tail (TAL/SVL 1.56-1.89 vs. 2.33-2.71), the presence of vermiculate stripes on ventral head (vs. absence), and having wide, strongly jagged dorsolateral stripes in males (vs. narrow, smooth edged).

Distribution.

This species is currently known only from its type locality in Tacheng Town, Weixi County, Diqing Prefecture, Yunnan Province, China (Fig. 1 ).

Natural history.

All specimens were collected between 1 and 5 p.m. on the ground in the secondary coniferous forest (Fig. 16G, H ) beside the Lapu River, which is a tributary of the Jinsha River.

Figures

Figure 1. Map showing the type localities of Diploderma danbaense sp. nov. in Danba County, Ganzi Prefecture, Sichuan Province (black dot), Diploderma donglangense sp. nov. in Muli County, Liangshan Prefecture, Sichuan Province (black pentagon), Diploderma jiulongense sp. nov. in Jiulong County, Ganzi Prefecture, Sichuan Province (black triangle), and Diploderma tachengense sp. nov. in Weixi County, Diqing Prefecture, Yunnan Province (black square), in the Hengduan Mountain Region, southwestern China. The elevation data were obtained from Geospatial Data Cloud (2022).

Figure 13. Dorsal view (upper) and ventral view (lower) of the type series of Diploderma tachengense sp. nov. in preservative.

Figure 14. Holotype (KIZ 2022028) of Diploderma tachengense sp. nov. in life A dorsal view B lateral view C ventral view D close-up view of the dorsolateral side of the head E close-up view of the ventral side of the head F close-up view of the oral cavity.

Figure 15. Paratypes of Diploderma tachengense sp. nov. in life A, B the female paratype KIZ 2022029 C, D the subadult male paratype KIZ 2022038 E, F the subadult female paratype KIZ 2022039.

Figure 16. Habitats of the new species A distant view of the type locality of Diploderma danbaense sp. nov. B close view of the type locality of Diploderma danbaense sp. nov. C distant view of the type locality of Diploderma donglangense sp. nov. D close view of the type locality of Diploderma donglangense sp. nov. E distant view of the type locality of Diploderma jiulongense sp. nov. F close view of the type locality of Diploderma jiulongense sp. nov G distant view of the type locality of Diploderma tachengense sp. nov. H close view of the type locality of Diploderma tachengense sp. nov.