A New Species of Diploderma Hallowell, 1861 (Reptilia, Squamata, Agamidae) from Northeastern Yunnan Province, China ^†

Abstract

A new species of the genus Diploderma Hallowell, 1861 from Qiaojia County, Zhaotong City, northeastern Yunnan Province, China, is described. Phylogenetically, the new species is placed within the D. splendidum complex and has genetic distances of 7.3% and 7.5% from D. splendidum (Barbour & Dunn, 1919) sensu stricto and D. daduense Cai, Liu & Chang, 2024, respectively, based on the ND2 gene sequences. Morphologically, the new species closely resembles D. splendidum sensu stricto and D. daduense, however, it can be distinguished from D. splendidum sensu stricto by having a larger body size in males and relatively shorter limbs, and can be differentiated from D. daduense by having a relatively narrower head in males and relatively shorter forelimbs in males. In addition, the new species differs from D. splendidum sensu stricto and D. daduense by having different colorations, especially in the absence of transverse stripes on the dorsal head. This study further revealed that D. splendidum sensu lato is a complex containing multiple species and that more research is needed to clarify the taxonomy of the complex.

1. Introduction

Diploderma Hallowell, 1861 is a genus that has seen a rapid increase in the number of species recently, that making it the most speciose genus of lizards in China [1,2,3,4,5]. Previous taxonomic studies of the genus have focused largely on the D. flaviceps complex [2,6,7,8,9,10,11,12,13,14,15] and the D. fasciatum complex [16], whereas far less attention has been given to the D. splendidum complex.

Diploderma splendidum (Barbour & Dunn, 1919) was originally described from the gorge of the Yangtze River (Changjiang River) near Ichang (Yichang City), Hupeh (Hubei Province), central China [17,18], and it was later considered to be widely distributed along the middle section of the Changjiang River, from Hubei Province to Chongqing Municipality, and Sichuan, Guizhou, and Yunnan provinces, as well as along the lower reach of the Dadu River in Sichuan Province [19,20,21,22,23,24]. Recently, Cai et al. [3] revised the D. splendidum complex, restricted the distribution of D. splendidum sensu stricto to around its type locality in Hubei Province and two possible introduced localities in Fujian Province and northeastern Sichuan Province only, and described the population previously considered to be D. splendidum from the Dadu River drainage basin as a new species, namely D. daduense Cai, Liu & Chang, 2024.

Since the distribution of Diploderma splendidum sensu stricto is restricted to Hubei, Fujian, and northeastern Sichuan, what is it about the taxonomic status of the population that it was previously considered to be D. splendidum from Yunnan? To address this issue, we re-examined the specimens previously identified as D. splendidum collected from northeastern Yunnan. We found that these specimens closely resemble D. splendidum sensu stricto and D. daduense but can be distinguished from them due to having obviously different colorations. In addition, phylogenetic analysis also revealed that the specimens from Yunnan are not conspecific with D. splendidum sensu stricto and D. daduense. Herein, we describe the specimens from northeastern Yunnan as a new species of Diploderma.

2. Materials and Methods

2.1. Sampling

The specimens were collected from Qiaojia County, Zhaotong City, Yunnan Province, China, preserved in 75% ethanol, and then deposited at Kunming Natural History Museum of Zoology, Kunming Institute of Zoology, Chinese Academy of Sciences (KIZ).

2.2. Morphology

Measurements were taken to the nearest 0.1 mm with an electronic vernier caliper. Paired meristic characters are given as left/right. Measurements and scale counts were taken following Cai et al. [3]: SVL, snout to vent length, measured from the tip of the snout to the vent; TAL, tail length, measured from the vent to the tip of the tail; HL, head length, measured from the tip of the snout to the angle of the jaw; HW, head width, measured between the widest points of the temporal region; SEL, snout to eye length, measured from the tip of the snout to the anterior edge of the eye; TNC, tallest nuchal crest spine length, measured from the bottom to the tip of the tallest nuchal crest spine; FLL, forelimb length, measured from the axilla to the tip of the fourth finger (excluding the claw, which is measured on the straightened limb); HLL, hindlimb length, measured from the groin to the tip of the fourth toe (excluding the claw, which is measured on the straightened limb); TRL, trunk length, measured from the axilla to the groin; T4L, fourth toe length, measured from the joint of the third and fourth toes to the tip of the fourth toe (excluding the claw); SL, supralabial scale number, counted between the rostral and the corner of the mouth; IL, infralabial scale number, counted between the mental and the corner of the mouth; NSL, nasal–supralabials scale rows, the number of horizontal rows of the small scales between the first supralabial and the nasal; MD, middorsal crest scale number, counted longitudinally from the first nuchal crest to the dorsal crest scale that above the vent; VN, ventral scale number, counted in a straight line along the medial axis between the transverse gular fold and the vent; GU, gular scale number, counted in a straight line along the medial axis between the mental and the transverse gular fold; F4S, fourth finger subdigital lamellae, the number of subdigital lamellae scales from the joint of the third and fourth fingers to the tip of the fourth finger (excluding the claw); and T4S, fourth toe subdigital lamellae, the number of subdigital lamellae scales from the joint of the third and fourth toes to the tip of the fourth toe (excluding the claw).

2.3. Molecular Analysis

The total genomic DNA was extracted from the liver tissues, which were stored in 99% ethanol. The mitochondrial gene NADH dehydrogenase subunit 2 (ND2) was amplified and sequenced using published primers [25]. Molecular experiments were performed by Tsingke Biotechnology Co., Ltd. (Bei**g, China). Sequences were assembled and proofread in SeqMan in Lasergene 7.1 [26] and MEGA 11 [27]. The sequences of other species of Diploderma and the outgroups were obtained from GenBank (

Table 1. GenBank accession numbers for the sequences used in this study.

Species	Voucher	Locality	Accession
Diploderma angustelinea	KIZ 029704	Muli, Sichuan, China	MT577930
Diploderma aorun	KIZ 032733	Benzilan, Yunnan, China	MT577938
Diploderma batangense	KIZ 09404	Zhubalong, Tibet, China	MK001412
Diploderma brevicauda	KIZ 044305	Lijiang, Yunnan, China	MW506021
Diploderma bowoense	KIZ 044757	Muli, Sichuan, China	MW506020
Diploderma brevipes	NMNS 19607	Taiwan, China	MK001429
Diploderma chapaense	ZMMU NAP-01911	Chapa, Vietnam	MG214262
Diploderma daduense	CIB-CB2021227	Hanyuan, Sichuan, China	PP539949
Diploderma daduense	CIB-CB2021228	Hanyuan, Sichuan, China	PP539950
Diploderma daduense	CIB-CB2021229	Hanyuan, Sichuan, China	PP539951
Diploderma daduense	CIB-CB2021230	Hanyuan, Sichuan, China	PP539952
Diploderma daduense	CIB-CB2021237	**kouhe, Sichuan, China	PP539953
Diploderma daduense	CIB-CB2021238	**kouhe, Sichuan, China	PP539954
Diploderma daduense	CIB-CB2021239	**kouhe, Sichuan, China	PP539955
Diploderma daduense	CIB-CB2021240	**kouhe, Sichuan, China	PP539956
Diploderma daduense	CIB-CB2021241	Ebian, Sichuan, China	PP539957
Diploderma daduense	CIB-CB2021242	Ebian, Sichuan, China	PP539958
Diploderma daduense	CIB-CB2021246	Shimian, Sichuan, China	PP539959
Diploderma daduense	CIB-CB2021247	Shimian, Sichuan, China	PP539960
Diploderma daduense	CIB-CB2021248	Shimian, Sichuan, China	PP539961
Diploderma daduense	CIB-CB2021249	Shimian, Sichuan, China	PP539962
Diploderma daduense	CB2021252	**kouhe, Sichuan, China	PP539963
Diploderma daduense	CIB-CB2021253	Shimian, Sichuan, China	PP539964
Diploderma daduense	CIB-CB2021268	Emeishan, Sichuan, China	PP539965
Diploderma daduense	CIB-201806029	**kouhe, Sichuan, China	PP539941
Diploderma daduense	CIB-201806030	**kouhe, Sichuan, China	PP539942
Diploderma daduense	CIB-201806031	**kouhe, Sichuan, China	PP539943
Diploderma daduense	CIB-201806033	**kouhe, Sichuan, China	PP539944
Diploderma daduense	CIB-201806034	**kouhe, Sichuan, China	PP539945
Diploderma daduense	CIB-201806036	**kouhe, Sichuan, China	PP539946
Diploderma daduense	CIB-2023SCGZ0302	Jiulong, Sichuan, China	PP539947
Diploderma daduense	CIB-2023SCGZ0304	Jiulong, Sichuan, China	PP539948
Diploderma danbaense	KIZ2022048	Danba, Sichuan, China	OQ378180
Diploderma daochengense	DC001	Daocheng, Sichuan, China	OP595621
Diploderma donglangense	KIZ2022057	Muli, Sichuan, China	OQ378185
Diploderma drukdaypo	KIZ 027627	**duo, Tibet, China	MT577950
Diploderma dymondi	KIZ 040639	Dongchuan, Yunnan, China	MK001422
Diploderma fasciatum	KIZ 040192	Daweishan, Yunnan, China	OM055800
Diploderma flaviceps	KIZ 01851	Luding, Sichuan, China	MK001416
Diploderma flavilabre	KIZ 032692	Baiyu, Sichuan, China	MT577916
Diploderma formosgulae	KIZ 044420	Deqin, Yunnan, China	MW506024
Diploderma iadinum	KIZ 027697	Yunling, Yunnan, China	MT577956
Diploderma jiulongense	KIZ2022086	Jiulong, Sichuan, China	OQ378190
Diploderma kangdingense	20210916	Kangding, Sichuan, China	OP595625
Diploderma laeviventre	KIZ 014037	Basu, Tibet, China	MK001407
Diploderma limingense	KIZ2022015	Yulong, Yunnan, China	OP428783
Diploderma luei	NMNS 19604	Taiwan, China	MK001433
Diploderma makii	NMNS 19609	Taiwan, China	MK001431
Diploderma menghaiense	KIZ L0030	Menghai, Yunnan, China	MT598655
Diploderma micangshanense	KIZ 032801	Shiyan, Hubei, China	MK578665
Diploderma panchi	KIZ 032715	Yajiang, Sichuan, China	MT577946
Diploderma panlong	KIZ 040137	Miansha, Sichuan, China	MT577906
Diploderma polygonatum	NMNS 19598	Taiwan, China	MK001427
Diploderma qilin	KIZ 028332	Deqin, Yunnan, China	MT577941
Diploderma shuoquense	KIZ2022004	**, Chongqing, China	PP889942
Diploderma sp.3	CQWL	Wulong, Chongqing, China	PP889943
Laodracon carsticola	NUOL.R.2022.01	Khammuone, Laos	OR544068
Pseudocalotes kakhiensis	KIZ 015975	Gongshan, Yunnan, China	MK001435

).

The sequences were aligned in MAFFT 7.471 [28] with default parameters. The uncorrected pairwise distances (p-distance) were calculated in MEGA 11 [27]. The best substitution models were selected in ModelFinder [29] using the Akaike Information Criterion. Bayesian inference (BI) was performed in MrBayes 3.2.6 [30] using the GTR + F + I + G4 model for the first and second codon positions and the GTR + F + G4 model for the third codon position. Maximum likelihood (ML) phylogenetic analysis was performed in IQ-TREE 1.6.12 [31] using the GTR + F + I + G4 model for the first and second codon positions and the GTR + F + R3 model for the third codon position. The technical computation methods used for the BI and ML analyses were the same as those used in Nguyen et al. [32].

3. Results

3.1. Phylogenetic Relationship

The resulting topologies from the BI and ML analyses were consistent and revealed that there are six highly divergent clades within the Diploderma splendidum complex. One clade consisting of sequences mainly from Hubei Province represents D. splendidum sensu stricto, and one clade consisting of sequences from the Dadu River valley represents D. daduense. The remaining four clades consisting of sequences from Qiaojia County (new species described below), Yibin City (sp.1), Leibo County (sp.2), and Chongqing Municipality (sp.3), respectively, represent four unnamed species (Figure 1). The average p-distance between the clade from Qiaojia and D. splendidum sensu stricto was 7.3%, the average p-distance between the clade from Qiaojia and D. daduense was 7.5%, and the average p-distance between the clade from Qiaojia and its sister clade from Leibo was 3.7% (Supplementary Material, Table S1). All of them were distinctly larger than those of the intraspecific average p-distance in this complex (0.8% within D. splendidum sensu stricto, 1.4% within D. daduense, 0 within sp.1, 0.3% within sp.2, 0.9% within sp.3, and 0.2% within the new species).

3.2. Taxonomic Account

Class Reptilia Laurenti, 1768

Order Squamata Oppel, 1811

Family Agamidae Gray, 1827

Genus Diploderma Hallowell, 1861

Species Diploderma qiaojiaense sp. nov.

urn:lsid:zoobank.org:act:3EFB02BF-533E-4752-B730-1CD66AD65733

(Figure 2, Figure 3, Figure 4 and Figure 5)

Figure 1. Bayesian tree of the genus Diploderma inferred from the ND2 sequences. The Bayesian posterior probability support/ML bootstrap support is denoted beside each node.

Figure 1. Bayesian tree of the genus Diploderma inferred from the ND2 sequences. The Bayesian posterior probability support/ML bootstrap support is denoted beside each node.

Figure 2. Holotype (KIZ2021106) of Diploderma qiaojiaense sp. nov. in life. (A) Dorsal view; (B) lateral view; (C) ventral view; (D) close-up view of the lateral side of the head; (E) close-up view of the ventral side of the head; and (F) close-up view of the oral cavity.

Figure 2. Holotype (KIZ2021106) of Diploderma qiaojiaense sp. nov. in life. (A) Dorsal view; (B) lateral view; (C) ventral view; (D) close-up view of the lateral side of the head; (E) close-up view of the ventral side of the head; and (F) close-up view of the oral cavity.

Figure 3. Female paratype (KIZ2021108) of Diploderma qiaojiaense sp. nov. in life. (A) Dorsal view; (B) lateral view; (C) ventral view; (D) close-up view of the lateral side of the head; (E) close-up view of the ventral side of the head; and (F) close-up view of the oral cavity.

Figure 3. Female paratype (KIZ2021108) of Diploderma qiaojiaense sp. nov. in life. (A) Dorsal view; (B) lateral view; (C) ventral view; (D) close-up view of the lateral side of the head; (E) close-up view of the ventral side of the head; and (F) close-up view of the oral cavity.

Figure 4. Body and corresponding throat colorations in the males of Diploderma qiaojiaense sp. nov. under different environmental conditions. High temperature in the afternoon (top), basking to raise body temperature in the morning (bottom), and the state between the other two (middle). Specimens were not collected.

Figure 4. Body and corresponding throat colorations in the males of Diploderma qiaojiaense sp. nov. under different environmental conditions. High temperature in the afternoon (top), basking to raise body temperature in the morning (bottom), and the state between the other two (middle). Specimens were not collected.

Figure 5. Type series of Diploderma qiaojiaense sp. nov. in preservative. (A) Dorsal view and (B) ventral view.

Figure 5. Type series of Diploderma qiaojiaense sp. nov. in preservative. (A) Dorsal view and (B) ventral view.

Holotype. KIZ2021106, adult male, collected on 9 April, 2021 by Shuo Liu from the middle **sha River Valley, Niulan Village, Hongshan Township, Qiaojia County, Zhaotong City, Yunnan Province, China (27°24′5″ N, 103°6′40″ E, 620 m elevation).

Paratypes. KIZ2021101–KIZ2021105 and KIZ2021107, six adult males, and KIZ2021108, one adult female, the collecting data was the same as that of the holotype.

3.3. Diagnosis

Body size relatively large, SVL 88.4–95.9 mm in adult males; tail moderately long, TAL/SVL 2.17–2.29; limbs relatively short, FLL/SVL 0.39–0.42, HLL/SVL 0.69–0.73; head relatively long, HL/SVL 0.32–0.35; tympanum concealed; ventral head and body scales strongly keeled, some enlarged scales interspersed on ventral head; nuchal crest well-developed, dorsal crest moderately developed; strongly erected skin folds under nuchal and dorsal crests present. Dorsal surface of head light brownish grey with no transverse bands; transverse black stripe on upper lip indistinct, region between stripe beneath eye and stripe on upper lip pure white; dorsolateral stripe light green in males in life, upper edge straight or slightly jagged, lower edge straight; gular spot absent, some white spots with indistinct black circle surrounded present on ventral head; oral cavity, inner lips, and tongue light flesh color.

3.4. Etymology

The specific epithet refers to Qiaojia County, which is where the new species was discovered.

3.5. Description of Holotype

Adult male, SVL 88.4 mm; tail long, TAL/SVL 2.29; limbs relatively short, FLL/SVL 0.42, HLL/SVL 0.72. Head elongate triangular, HW/HL 0.60; snout relatively long, SEL/HL 0.41. Rostral elongate, bordered first supralabial laterally and five postrostrals posteriorly; dorsal head scales heterogeneous, all keeled; a Y-shaped ridge on dorsal snout. Nasal oval, bordered first supralabial anteroinferiorly and separated from second supralabial by one row of scales; loreals small, keeled; canthus rostralis elongated, overlap** with each other; one row of enlarged, keeled scales forming a ridge from posteroinferior eye to posterosuperior tympanum; tympanum concealed under small scales; SL 8/8, smooth. Mental approximately triangular, bordered first infralabial laterally, first enlarged chin shield posterolaterally, and one small postmental posteriorly; IL 8/8; enlarged chin shields 9/8, smooth, first one connected IL, second one separated from IL by one row of scales, remaining ones separated from IL by 2–3 rows of scales; ventral head interspersed with some enlarged scales, other ventral head scales approximately equal in size, all strongly keeled; transverse gular fold distinct; gular pouch feebly developed.

Shoulder fold feebly developed; dorsal body scales heterogeneous in size and shape, all keeled, tip pointing backwards; axillary scales smaller than remining dorsals; one intermittent longitudinal row of enlarged dorsal scales between dorsal crest and dorsolateral stripe on each side, remaining enlarged dorsal scales irregularly scattered on each side of body. Nuchal crest well-developed; dorsal crest moderately developed, discontinuous with nuchal crest; strongly erected skin folds under nuchal and dorsal crests present in life; MD 48. Dorsal limb scales strongly keeled, homogeneous on fore-limbs and heterogeneous on hind limbs; F4S 19/18, T4S 23/24. Ventral body scales approximately parallel, homogeneous, all strongly keeled, VN 62. Ventral limb scales parallel, small on upper arms and thighs and large on forearms and crus, all strongly keeled. Tail scales all strongly keeled, ventral tail scales obviously larger than dorsal tail scales.

3.6. Coloration of Holotype in Life

Dorsal surface of head light brownish grey with some tiny black dots, no transverse bands on dorsal head. Lateral surface of head light brownish grey, several thin black stripes around eye not forming obvious radial pattern. A distinct black stripe beneath eye from posterior nostril through bottom of orbit to superior mouth corner and an indistinct discontinuous black stripe on upper lip from inferior nostril to mouth corner on each side, region between two stripes white. Oral cavity, inner lips, and tongue light flesh color.

Dorsal surface between dorsolateral stripes gradually from black to greyish brown posteriorly with some indistinct light transverse bands. Dorsolateral stripe light green, upper edge slightly jagged, lower edge straight. Lower flank mottled with black and light brown. Dorsal surfaces of limbs light green with some indistinct dark stripes not forming obvious transverse bands. Dorsal surface of basal tail grey with no transverse bands, dorsal surface of other region of tail chequered with black and white.

Ventral surface of head greyish white, some white spots surrounded by indistinct black circles on ventral surface of head. No gular spot. Ventral surface of body white, ventral surfaces of limbs white with some irregular dark stripes. Ventral surface of basal tail white with no transverse bands, ventral surface of other region of tail chequered with black and white.

3.7. Variations

The variations in the metrical characteristics of the type series are provided in

Table 2. The morphological data of the type series of Diploderma qiaojiaense sp. nov. The morphometric measurements are in mm. See Section 2 for the measurement and count methods and abbreviations.

	KIZ2021106 Holotype Male	KIZ2021101 Paratype Male	KIZ2021102 Paratype Male	KIZ2021103 Paratype Male	KIZ2021104 Paratype Male	KIZ2021105 Paratype Male	KIZ2021107 Paratype Male	KIZ2021108 Paratype Female
SVL	88.4	95.9	92.4	91.9	94.3	94.2	88.8	72.3
TAL	202.0	207.9	208.0	209.4	212.0	207.4	198.9	163.4
HL	29.5	32.7	31.1	29.9	32.2	32.9	28.5	22.8
HW	17.8	18.9	18.7	18.0	18.9	19.0	17.2	14.0
SEL	12.1	13.1	12.2	11.9	12.9	13.6	11.9	9.9
TNC	2.2	2.4	2.5	1.8	1.9	2.0	1.9	1.1
FLL	37.5	39.7	38.5	39.0	39.5	39.9	34.5	30.4
HLL	64.0	66.9	64.3	64.7	66.1	66.9	61.4	52.7
TRL	39.2	44.8	41.9	44.1	42.9	43.4	39.7	34.7
T4L	16.2	17.0	17.1	17.0	16.9	16.6	15.5	13.0
SL	8/8	8/8	8/9	9/8	8/9	8/8	8/8	9/8
IL	8/8	8/8	9/10	7/8	9/9	9/9	9/8	9/9
NSL	1/1	1/1	1/1	1/1	1/0	1/1	1/1	1/1
VN	62	65	69	61	71	63	73	62
GU	31	28	29	27	34	32	31	29
MD	48	48	47	52	46	43	51	49
F4S	19/18	17/18	18/19	20/19	19/19	17/18	18/18	18/19
T4S	23/24	26/24	26/26	27/26	25/24	23/23	24/25	25/25
TAL/SVL	2.29	2.17	2.25	2.28	2.25	2.20	2.24	2.26
HL/SVL	0.33	0.34	0.34	0.33	0.34	0.35	0.32	0.32
HW/HL	0.60	0.58	0.60	0.60	0.59	0.58	0.60	0.61
SEL/HL	0.41	0.40	0.39	0.40	0.40	0.41	0.42	0.43
FLL/SVL	0.42	0.41	0.42	0.42	0.42	0.42	0.39	0.42
HLL/SVL	0.72	0.70	0.70	0.70	0.70	0.71	0.69	0.73
TRL/SVL	0.44	0.47	0.45	0.48	0.45	0.46	0.45	0.48
TNC/HL	0.07	0.07	0.08	0.06	0.06	0.06	0.07	0.05
T4L/HLL	0.25	0.25	0.27	0.26	0.26	0.25	0.25	0.25

. The variations in coloration are as follows: there are a series of brownish black, hollow, and approximately rhomboid patterns between the dorsolateral stripes running from the neck to the base of the tail, the dorsolateral stripe is white, there are distinct transverse bands on the dorsal surfaces of the limbs, and there are no white spots that are surrounded by black circles, but there are some dark gray spots on the ventral surface of the head in the female paratype (Figure 3). In addition, it is worth noting that this species was found to have a relatively strong ability to change body color. The dorsal surface of the head can change from light brownish gray to brown, the dorsal surface between the dorsolateral stripes and the lower flanks can change from mottled to solid black, and the ventral surface of the head can change from grayish white with white spots that are surrounded by black circles to brownish gray with white spots that have no black circles surrounding them and to black with white spots in males (Figure 4).

3.8. Dentition

Dentition is one of the most important diagnostic characteristics of Agamidae, and the tricuspidity in the acrodont teeth is a typical characteristic of Draconinae [33,34]. In addition to collecting the type specimens, we also discovered a decaying corpse of the new species at the type locality. We brought it back and peeled off its skull. Therefore, we were able to describe the dentition of the skull: Premaxillary teeth six, pleurodont, one on right side damaged. Maxillary teeth 16 on right side, part of maxilla and maxillary teeth damaged on left side. Anterior most maxillary tooth large, pleurodont, canine shaped, tip curved backwards on each side. Other maxillary teeth acrodont, tricuspid, gradually enlarge posteriorly and then shrink near posterior most. Mandibular teeth 19 on right side and 18 on left side. Anterior three mandibular teeth pleurodont, first one small, second and third large, canine shaped, tip slightly curved backwards on each side. Other mandibular teeth acrodont, tricuspid, gradually enlarge posteriorly and then shrink near posterior most (Figure 6).

3.9. Comparisons

Diploderma qiaojiaense sp. nov. differs from the species of Diploderma that are mainly distributed outside of the Hengduan Mountains Region, namely D. brevipes (Gressitt, 1936), D. chapaense (Bourret, 1937), D. fasciatum (Mertens, 1926), D. hamptoni (Smith, 1935), D. luei (Ota, Chen & Shang, 1998), D. makii (Ota, 1989), D. menghaiense Liu, Hou, Wang, Ananjeva & Rao, 2020, D. ngoclinense (Ananjeva, Orlov & Nguyen, 2017), D. polygonatum Hallowell, 1861, and D. swinhonis (Günther, 1864), due to the presence of a transverse gular fold (vs. absence).

Diploderma qiaojiaense sp. nov. differs from D. dymondi (Boulenger, 1906), D. panlong Wang, Che & Siler, 2020, D. slowinskii (Rao, Vindum, Ma, Fu & Wilkinson, 2017), D. varcoae (Boulenger, 1918), and D. swild Wang, Wu, Jiang, Chen, Miao, Siler & Che, 2019, due to having a concealed tympana (vs. exposed).

Diploderma qiaojiaense sp. nov. differs from D. angustelinea Wang, Ren, Wu, Che & Siler, 2020, D. aorun Wang, Jiang, Zheng, **e, Che & Siler, 2020, D. batangense (Li, Deng, Wu & Wang, 2001), D. bowoense Wang, Gao, Wu, Siler & Che, 2021, D. brevicauda (Manthey, Denzer, Hou & Wang, 2012), D. daochengense Cai, Zhang, Li, Du, **e, Hou, Zhou & Jiang, 2022, D. donglangense Liu, Hou, Ananjeva & Rao, 2023, D. flavilabre Wang, Che & Siler, 2020, D. formosgulae Wang, Gao, Wu, Dong, Shi, Qi, Siler & Che, 2021, D. iadinum (Wang, Jiang, Siler & Che, 2016), D. jiulongense Liu, Hou, Ananjeva & Rao, 2023, D. laeviventre (Wang, Jiang, Siler & Che, 2016), D. limingensis Liu, Hou, Rao & Ananjeva, 2022, D. panchi Wang, Zheng, **e, Che & Siler, 2020, D. qilin Wang, Ren, Che & Siler, 2020, D. tachengense Liu, Hou, Ananjeva & Rao, 2023, D. xinlongense Cai, Zhang, Li, Du, **e, Hou, Zhou & Jiang, 2022, D. yangi Wang, Zhang & Li, 2022, D. yongshengense Liu, Hou, Rao & Ananjeva, 2022, D. yulongense (Manthey, Denzer, Hou & Wang, 2012), D. yunnanense (Anderson, 1878), and D. zhaoermii (Gao & Hou, 2002) due to the absence of a gular spot in males in life (vs. the presence of a colorful gular spot).

Diploderma qiaojiaense sp. nov. differs from D. danbaense Liu, Hou, Ananjeva & Rao, 2023 and D. flaviceps (Barbour & Dunn, 1919) due to having light green dorsolateral stripes in males in life (vs. yellow) and the absence of a reticulated pattern on the ventral surface of the head (vs. presence). It differs from D. drukdaypo (Wang, Ren, Jiang, Zou, Wu, Che & Siler, 2019) due to having a much larger body size and strongly keeled ventral body scales (vs. smooth or weakly keeled). It differs from D. grahami (Stejneger, 1924) due to having relatively longer hind limbs (HLL/SVL 0.69–0.73 vs. 0.61), the presence of dorsolateral stripes (vs. absence), and the absence of a gular spot after preservation (vs. presence). It differs from D. kangdingense Cai, Zhang, Li, Du, **e, Hou, Zhou & Jiang, 2022 due to having light green dorsolateral stripes in males in life (vs. yellow) and a white ventrolateral body surface in males in life (vs. yellow). It differs from D. micangshanense (Song, 1987) due to having light green dorsolateral stripes in males in life (vs. yellow) and the presence of a transverse gular fold (vs. absence). It differs from D. shuoquense Liu, Hou, Rao & Ananjeva, 2022 due to having a much larger body size, strongly keeled ventral head scales (vs. smooth or weakly keeled), and the presence of skin folds under the nuchal and dorsal crests in males in life (vs. absence). It differs from D. vela (Wang, Jiang & Che, 2015) due to having light green dorsolateral stripes in males in life (vs. yellow) and discontinuous nuchal and dorsal crests and skin folds in males in life (vs. continuous nuchal and dorsal crests on the continuous skin fold).

Diploderma qiaojiaense sp. nov. is phylogenetically sister to and is most similar in morphology characteristics with D. splendidum sensu stricto and D. daduense, however, Diploderma qiaojiaense sp. nov. can be differentiated from D. splendidum sensu stricto due to having a larger body size in males (SVL 88.4–95.9 mm vs. 69.7–83.3 mm), shorter limbs (FLL/SVL 0.39–0.42 vs. 0.47–0.54 in males, 0.42 vs. 0.45–0.52 in females; HLL/SVL 0.69–0.72 vs. 0.78–0.89 in males, 0.73 vs. 0.77–0.81 in females), and a relatively shorter tail in males (TAL/SVL 2.17–2.29 vs. 2.26–2.70). Diploderma qiaojiaense sp. nov. further differs from D. splendidum sensu stricto due to the absence of transverse stripes on the dorsal head (vs. the presence of distinct transverse stripes on the dorsal head), the black stripe on the upper lip being relatively less distinct (vs. relatively more distinct), the region between the stripe beneath the eye and the stripe on the upper lip being pure white (vs. yellow, yellowish green, or yellowish white, rarely pure white), having relatively more distinct enlarged scales on the ventral head (vs. relatively less distinct), and having no or few enlarged scales posterior to the corner of the mouth (vs. a series of enlarged scales posterior to the corner of the mouth). Diploderma qiaojiaense sp. nov. can be differentiated from D. daduense due to having a narrower head in males (HW/HL 0.58–0.60 vs. 0.61–0.79) and relatively shorter forelimbs in males (FLL/SVL 0.39–0.42 vs. 0.41–0.49). In addition, Diploderma qiaojiaense sp. nov. mainly differs from D. daduense due to having a light brownish gray dorsal head surface and no transverse stripes on the dorsal head (vs. a yellow, yellowish green, or green dorsal head surface with distinct black transverse stripes), the black stripe on the upper lip being relatively less distinct (vs. relatively more distinct), the region between the stripe beneath the eye and the stripe on the upper lip being pure white (vs. yellow, green, yellowish white, or greenish white, rarely pure white), the dorsolateral stripe being light green in males and pale white in female (vs. green–yellow anteriorly, cyan in center, and blurry off-white posteriorly in males, and greenish in females), having relatively more distinct enlarged scales on the ventral head (vs. relatively less distinct), and having relatively fewer and smaller enlarged spine-like scales at the corner of the jaw (vs. more and larger enlarged spine-like scales at the corner of the jaw). See Figure 7 for comparisons of the head details of Diploderma qiaojiaense sp. nov., D. daduense, and D. splendidum sensu stricto.

3.10. Distribution

This species is currently known only from its type locality in Qiaojia County, Zhaotong City, Yunnan Province, China (Figure 8).

3.11. Natural History

The new species inhabits the hot-dry valley of the middle **sha River Valley. There are some small trees and many rocks at the type locality (Figure 9). This species is active between 11:00 a.m. to 5:00 p.m. The male specimens were collected when they were basking on rocks, and the female specimen was collected from a tree branch.

4. Discussion

Diploderma splendidum sensu lato is a kind of relatively large-sized and good-looking lizard, so they have been very popular in the pet trade. Therefore, it is very necessary to clarify how many species are included in the D. splendidum complex, investigate the distribution range of each species, and evaluate their threatened status in order to better protect these beautiful creatures. In addition, pets are often released by pet keepers or wildlife protection organizations or departments. Since D. splendidum sensu lato has been confirmed to contain more than a single species, the decision to release them should be treated with more caution. If the released individuals do not belong to the same species as the local population of D. splendidum sensu lato, the released individuals may not survive or cause genetic contamination.

Morphologically, Diploderma qiaojiaense sp. nov. closely resembles D. daduense as they both have a relatively large body size, a relatively short tail, and relatively short limbs, which are different traits from D. splendidum sensu stricto. However, Diploderma qiaojiaense sp. nov. cannot be distinguished from D. daduense by most metric and scale characteristics, but there are some stable differences in coloration between them, which is enough to distinguish the two species. Perhaps the metric and scale characteristics are relatively conservative for this group, although Diploderma qiaojiaense sp. nov. and D. daduense have evolved independently, they have not produced significant metric and pholidosis differences. Conversely, coloration may have a relatively fast variation rate for this group, so the two species have produced obvious differences in coloration after independent evolution. Of course, after independent evolution, it may also cause some other differences that cannot be directly observed, such as differences in bones, physiology, and habits. These speculations need further research to verify.

In the original description of Diploderma splendidum, the throat was described as “conspicuously streaked, longitudinally, with brown on a yellow ground” [17]. However, nearly all subsequent descriptions [19,20,21,35] of this species have not recorded that the throat of this species is yellow. This is because most of these subsequent descriptions were based on specimens from Sichuan or Yunnan, and almost no specimens were from its type locality in Yichang, Hubei. Cai et al. [2] collected some topotypic specimens of this species and found that the throat of the males is yellow to green–yellow in life, which is approximately consistent with the original description. In addition, Xu et al. [36] discovered a naturalized population of this species in Fujian Province. Phylogenetically, the sequences of the specimens from Fujian clustered with, and showed negligible genetic distance with, the sequences of D. splendidum from its type locality [3,36]. It can be judged that the population from Fujian and D. splendidum sensu stricto should be conspecific. Xu et al. [36] described that the throat of the male specimen is yellow, this finding is consistent with Cai et al. [3] and the original description of this species. In conclusion, we believe that the throats of some male individuals of D. splendidum sensu stricto are yellow, but we are not sure if all male individuals of D. splendidum sensu stricto have yellow throats. Therefore, we did not use the throat color as a distinguishing characteristic between Diploderma qiaojiaense sp. nov. and D. splendidum sensu stricto. More research is needed to verify whether the throat color is a stable characteristic that can distinguish D. splendidum sensu stricto from other species in the D. splendidum complex.

In addition to describing Diploderma daduense, Cai et al. [3] also revealed two unnamed species within the D. splendidum complex, namely sp.1 from Yibin City and sp.2 from Leibo County, Sichuan Province, China, respectively. In this study, we further revealed that the population in Chongqing Municipality is also a cryptic species (sp.3), and this reminded us that more field surveys and detailed studies are needed to find out how many species remain in the D. splendidum complex.