A new species of the genus Takydromus (Squamata: Lacertidae) from Tianjingshan Forestry Station, northern Guangdong, China

Abstract

Many early descriptions of species of the genus Takydromus were based on limited diagnostic characteristics. This has caused considerable challenges in accurate species identification, meaning that a number of cryptic species have been erroneously identified as known species, resulting in substantially underestimated species diversity. We have integrated evidence from morphology and DNA sequence data to describe a new species of the Asian Grass Lizard, Takydromus albomaculosus sp. nov., based on two specimens from Tianjingshan Forestry Station, Ruyuan County, Guangdong Province, China. The new species can be distinguished from other known Takydromus species by distinctive morphological differences and significant genetic divergence in the mitochondrial COI gene. Morphologically, the new species differs from the known 22 congeners in the following combination of characters: relatively large body size, SVL 70.9 mm in female, 65.5 mm in male; presence of three or four pairs of femoral pores and four pairs of chin-shields; supraoculars three, rarely four, the posterior loreal either in contact with the anteriormost supraocular or not; the presence of supraciliary granules; the presence of six rows of ventral scales, strongly keeled in the male, and smooth but with the outermost row keeled in the female; the presence of enlarged and keeled lateral scales in a row above the ventrals, but shorter than the ventrals; subdigital lamellae 23-24 under the fourth finger and 29-30 under the fourth toe; dorsal surface brown, ventral surface green, flank dark brown or brown black with several prominent white round spots; the presence of a pair of white longitudinal dorsolateral stripes and a pair of white longitudinal ventrolateral stripes. Takydromus albomaculosus sp. nov. represents the twenty-third species of this genus, of which six species occur in northern Guangdong, where the biodiversity level of Takydromus is the second highest in the world, just below that of Taiwan.

A new species of the genus Takydromus (Squamata, Lacertidae) from southwestern Guangdong, China

“…Moreover, 20 external morphological characters were examined from the specimens listed in Appendix 1. Modified abbreviations of these characters followed Arnold (1997), Lue and Lin (2008) and Wang et al (2017) as follows:…”

“…Comparative morphological data were obtained from the literature for Takydromus albomaculosus (Wang et al 2017), T. hani (Chou et al 2001), T. viridipunctatus , and T. luyeanus (Lue and Lin 2008), T. sikkimensis (Bhupathy et al 2009), T. madaensis (Bobrov 2013), T. sylvaticus (Pope 1928, 1929; Yang and Wang 2010), T. smaragdinus and T. toyamai (Takeda and Ota 1996); T. kuehnei (van Denburgh 1909; Arnold 1997; Norval et al 2012; Wang et al 2017), T. intermedius (Stejneger 1924; Wang et al 2017), T. amurensis , T. dorsalis , T. formosanus , T. hsuehshanensis , T. sauteri , T. stejnegeri , and T. tachydromoides (Takeda and Ota 1996; Lue and Lin 2008), T. sexlineatus , T. wolteri , T. septentrionalis , and T. khasiensis (Arnold 1997; Zhao et al 1999). All examined specimens are listed in Appendix I.…”

“…Previous studies have revealed the very high biodiversity level of the genus Takydromus in southern China, for which the species diversity is just below that of Taiwan Island (Lue and Lin 2008; Wang et al 2017). During repeated field surveys in the Yunkai Mountains, located in southwestern Guangdong Province (Fig.…”

“…The Asian grass lizard genus Takydromus Daudin, 1802 currently contains 23 recognized species, widely distributed in the East Asian islands (Ryukyu Archipelago, Taiwan) and recorded from the Russian far east, extending southward across the Chinese mainland, Indochina, northeastern India, Borneo, the Natuna Islands, Sumatra, Bangka, and Java (Wang et al 2017; Uetz et al 2019). Eight species are recorded in mainland China: T. albomaculosus Wang, Gong, Liu & Wang, 2017, T. amurensis Peters, 1881, T. intermedius Stejneger, 1924, T. kuehnei van Denburgh, 1909, T. septentrionalis Günther, 1864, T. sexlineatus Daudin, 1802, T. sylvaticus Pope, 1928, and T. wolteri Fischer, 1885 (Zhao et al 1999; Cai et al 2011; Wang et al 2017).…”

“…The Asian grass lizard genus Takydromus Daudin, 1802 currently contains 23 recognized species, widely distributed in the East Asian islands (Ryukyu Archipelago, Taiwan) and recorded from the Russian far east, extending southward across the Chinese mainland, Indochina, northeastern India, Borneo, the Natuna Islands, Sumatra, Bangka, and Java (Wang et al 2017; Uetz et al 2019). Eight species are recorded in mainland China: T. albomaculosus Wang, Gong, Liu & Wang, 2017, T. amurensis Peters, 1881, T. intermedius Stejneger, 1924, T. kuehnei van Denburgh, 1909, T. septentrionalis Günther, 1864, T. sexlineatus Daudin, 1802, T. sylvaticus Pope, 1928, and T. wolteri Fischer, 1885 (Zhao et al 1999; Cai et al 2011; Wang et al 2017). In addition, T. formosanus Boulenger, 1894, T. hsuehshanensis Lin & Cheng, 1981, T. luyeanus Lue & Lin, 2008, T. sauteri Van Dengurgh, 1909, T. stejnegeri van Denburgh, 1912, and T. viridipunctatus Lue & Lin, 2008 are endemic to Taiwan Island; T. dorsalis Stejneger, 1904, T. smaragdinus Boulenger, 1887, T. tachydromoides Schlegel, 1838, and T. toyamai Takeda & Ota, 1996 are known only from Japan.…”