Obligatory parthenogenesis in vertebrates is restricted to squamate reptiles and evolved through hybridisation. Parthenogens can hybridise with sexual species, resulting in individuals with increased ploidy levels. We describe two successive hybridisations of the parthenogenetic butterfly lizards (genus Leiolepis) in Vietnam with a parental sexual species. Contrary to previous proposals, we document that parthenogenetic L. guentherpetersi has mitochondrial DNA and two haploid sets from L. guttata and one from L. reevesii, suggesting that it is the result of a backcross of a parthenogenetic L. guttata × L. reevesii hybrid with a L. guttata male increasing ploidy from 2n to 3n. Within the range of L. guentherpetersi, we found an adult tetraploid male with three L. guttata and one L. reevesii haploid genomes. It probably originated from fertilisation of an unreduced triploid L. guentherpetersi egg by a L. guttata sperm. Although its external morphology resembles that of the maternal species, it possessed exceptionally large erythrocytes and was likely sterile. As increased ploidy level above triploidy or tetraploidy appears to be harmful for amniotes, all-female asexual lineages should evolve a strategy to prevent incorporation of other haploid genomes from a sexual species by avoiding fertilisation by sexual males.

Parthenogenesis has been discovered in a great number of reptiles, indicating that parthenogens can outcompete bisexual species and hybridize with them. This raises intriguing questions: how do parthenogenetic species coexist with gonochoristic relatives, and what outcome does this coexistence produce? To answer these two questions, we studied relationships between male rock lizards, Darevskia valentini, and parthenogenetic Darevskia armeniaca. We compared social and sexual reactions of males to females of their own species and parthenogenetic D. armeniaca and vice versa. We found that females of both species basked together with males and demonstrated mostly submissive behaviour. Females of D. valentini were less aggressive towards males in the mixed-species population than in the single-species population, suggesting female competition for males. The proportion of successful and unsuccessful mating attempts with females of bisexual and unisexual species was equal, and we found no significant differences in male reactions to bisexual and unisexual females in sympatry. The proportion of females bearing mating scars on their venters and the number of these scars per female were greater in the bisexual species. This indicates that females of the bisexual species were more attractive than parthenogenetic females as mating partners to males. We found no triploid hybrids among the offspring of parthenogenetic females that mated with males in the mixed population. Our findings suggest that parthenogenetic species might outcompete bisexual species by mating with males and integrating into the social system.

Three rock lizard species (genus Darevskia) occur in the same mountain gorge of the Greater Caucasus mountains located in Northern Georgia. Whereas Darevskia caucasica and Darevskia derjugini belong to the same phylogenetic clade known as “caucasica”, Darevskia rudis is associated to the “rudis” clade. The mountain lizards differed interspecifically in their scalation and ventral colouration patterns, but the body proportions of D. caucasica and D. rudis were more similar to each other than to D. derjugini as both had flatter heads and longer limbs than D. derjugini. Females of all three species had longer trunks and shorter limbs than males. We hypothesized that hybrids occur more likely between D. derjugini and D. caucasica rather than between species belonging to different clades. However our analysis of microsatellite genotyping clearly revealed no traces of hybridisation and/or gene flow among any of the coexisting lizard species. The absence of individuals with intermediate morphological and genetic features reflects the presence of strong reproductive barriers at the prezygotic level.

We describe a new species of the Rhacophorus genus, which differs from its congeners on the basis of a combination of the following morphological characters: (1) medium body size (SVL of adult female — 50.4 mm); (2) head slightly wider than long (HW/HL 1.01); (3) HW/SVL 0.35; (4) HL/SVL 0.35; (5) third finger disk diameter much smaller than tympanum diameter (FTD/TD 0.70); (6) tympanum large, the lower edge of the tympanic annulus almost reaches the edge of the upper lip (TJ/TD 0.27, TJ/OJ 0.48, TJ/NJ 0.39); (7) high ratio TD/ED 0.73; (8) ratio TFL/FLL2 1.62; (9) vomerine odontophores oblique, and widely separated, between choanae (gap is equal to the length of one odontophore), touching anterior edge of choanae, vomerine teeth well developed; (10) triangular calcar absent; (11) color pattern of dorsal surface of head, body, shoulders, forearms, thighs, and shanks looks like a cross-connection between adjacent channels, tubes, fibers and other parts of a network of two general kinds of color: of reddish-brown and beige with small sparsely arranged individual black spots; (12) ventral surfaces of belly, throat, chest, femur and all forelimbs light gray, on the throat, chest and femur pigmentation is somewhat much intensive; (13) belly, throat and chest are smooth; (14) pair of tubercles ventrolaterally from the cloacal opening absent; (15) iris is brown; (16) fingers-webbing formula: I2+ – 3II12/3 – 21/2III2+ – 2IV; (17) toes-webbing formula: I11/2 – 2II1 – 2+III1+ – 21/2IV2+ – 1+V. At present, Rhacophorus trangdinhensis sp. nov. is known only by a single specimen (female) from the type locality in an evergreen forest on limestone karst from 200 m a.s.l. elevation.

To date, 20 species of Kurixalus Ye, Fei, and Dubois have been described, and all of these species are distributed throughout South and Southeast Asia, from eastern India, throughout Myanmar and the mountainous regions of southern China, to Indochina, western and northern peninsular Thailand, Malaysia, Sumatra, Borneo, and the Philippines (Frost 2021). Descriptions of the tadpoles of only 6 species have been published: K. berylliniris and K. wangi Wu, Huang, Tsai, Li, Jhang, Wu (Wu et al. 2016); K. eiffingeri (Boettger) (Kuramoto Wang 1987); K. idiootocus (Kuramoto Wang) (Kuramoto Wang 1987); K. cf. verrucosus (Boulenger) (Ziegler Vences 2002), and Kurixalus yangi Yu, Hui, Rao, Yang (Humtsoe et al. 2020). A description of the tadpoles of K. baliogaster (Inger, Orlov, Darevsky) is also given in the species description (Inger et al. 1999), but described larvae are assigned tentatively to this species in the published text. Additional studies on the identification of the conspecificity of the described tadpoles with K. baliogaster have not been conducted. Based on the much larger size of the tadpole body (TL up to 40.3 mm), as well as the labial tooth row formula 6(26)/5(1) given by Inger et al. (1999), we concluded that these described tadpoles cannot be larval K. baliogaster and most likely belong to some other species of rhacophorid frogs.

BACKGROUND:Caucasian rock lizards of the genus Darevskia are unique taxa, including both bisexual and parthenogenetic species. The parthenogenetic species have originated as a result of natural hybridisation between females and males of different bisexual species. The species involved in interspecific hybridisation are called parental. However, sympatric zones (SZ) of unisexual and bisexual rock lizards of the Caucasus are still poorly studied, although they are very important for understanding the role of hybrid individuals of different origin in reticulate evolution. This paper presents the location of the SZs of parthenogenetic and their parental bisexual rock lizards of the genus Darevskia in Armenia and adjacent territories of Georgia and Nagorno-Karabakh. We summarised the locations of the SZs identified from 1957 to the present, based on our field survey data gathered in 2018-2019 and records from publications and museum collections. This dataset includes 39 SZs of three types: SZ of parental bisexual species, SZ of parental species with unisexual species and SZ of the parthenogenetic species. For each zone, species composition, geographical and altitudinal distribution are presented. New records expand our knowledge of the geographical and altitudinal distribution of SZs in these species and provide additional data for understanding the mechanisms of reticulate evolution and hybridogeneous speciation in the past, present and future.NEW INFORMATION:The new records, including geographical and altitudinal distributions of three types of SZs, are presented, which expand the previously-known list to 39 locations of contact zones for parthenogenetic and its bisexual parental species of rock lizards of the genus Darevskia in Armenia and the adjacent territories of Georgia and Nagorno-Karabakh.

To date, 26 species of Theloderma have been described and all are distributed throughout Southeast Asia from Assam in northeastern India to Myanmar, Indochina, the Malay Peninsula, and the islands of the Greater Sundas: Sumatra and Borneo (Frost 2019). The tadpoles of only 12 species have been described and published: T. asperum (Boulenger); T. auratum Poyarkov, Kropachev, Gogoleva Orlov; T. bicolor (Bourret); T. corticale (Boulenger); T. gordoni Taylor; T. horridum (Boulenger); T. leave (Smith); T. moloch (Annandale); T. nebulosum Rowley, Le, Hoang, Dau Cao; T. palliatum Rowley, Le, Hoang, Dau Cao; T. stellatum Taylor; T. vietnamense Poyarkov, Orlov, Moiseeva, Pawangkhanant, Ruangsuwan, Vassilieva, Galoyan, Nguyen Gogoleva (Boulenger 1903; Annandale 1912; Wassersug et al. 1981; Inger et al. 1999; Leong Lim 2003; Inthara et al. 2005; Rowley et al. 2011; Gawor et al. 2012; Orlov et al. 2012; Poyarkov et al. 2015; Kropachev et al. 2018).

We describe a new species of the Rhacophorus genus, which differs from all species known in Asia by the combination of characters. It strongly differs also from small and middle-sized species of Rhacophorus sensu lato: Rhacophorus calcaneus Smith, 1924, Leptomantis cyanopunctatus (Manthey et Steiof, 1998), Rhacophorus hoabinhensis Nguyen, Pham, Nguyen, Ninh et Ziegler, 2017, Rhacophorus hoanglienensis Orlov, Lathrop, Murphy et Ho, 2001, Zhangixalus jarujini (Matsui et Panha, 2006), Rhacophorus laoshan Mo, Jiang, Xie et Ohler, 2008, Rhacophorus pardalis Günther, 1858, Rhacophorus rhodopus Liu et Hu, 1960, Rhacophorus robertingeri Orlov, Poyarkov, Vassilieva, Ananjeva, Nguyen, Sang, and Geissler, 2012, Leptomantis robinsonii (Boulenger, 1903), Rhacophorus spelaeus Orlov, Gnophanxay, Phimminith, and Phomphoumy, 2010, Rhacophorus translineatus Wu, 1977, Rhacophorus turpes Smith, 1940, Rhacophorus vampyrus Rowley, Le, Thi, Stuart et Hoang, 2010, Rhacophorus viridimaculatus Ostroshabov, Orlov et Nguyen, 2013 by having brown color with two green dorsolateral stripes starting at the groin level and connecting through the distal part of eyelid with green triangle on the head, slender body and head, lower ratio HW/HL 0.86, lower HW/SVL 0.28 and lower ratio HL/SVL 0.32.

A new species of small tree frog from a primary montane tropical forest of central Vietnam, Tay Nguyen Plateau, is described based on morphological, molecular, and acoustic evidence. The Golden Bug-Eyed Frog, Theloderma auratum sp. nov., is distinguishable from its congeners and other small rhacophorid species based on a combination of the following morphological attributes: (1) bony ridges on head absent; (2) smooth skin completely lacking calcified warts or asperities; (3) pointed elongated tapering snout; (4) vocal opening in males absent; (5) vomerine teeth absent; (6) males of small body size (SVL 21.8-26.4 mm); (7) head longer than wide; ED/SVL ratio 13%-15%; ESL/SVL ratio 16%-20%; (8) small tympanum (TD/EL ratio 50%-60%) with few tiny tubercles; (9) supratympanic fold absent; (10) ventral surfaces completely smooth; (11) webbing between fingers absent; (12) outer and inner metacarpal tubercles present, supernumerary metacarpal tubercle single, medial, oval in shape; (13) toes half-webbed: I 2-2¼ II 1½-2¾ III 2-3¼ IV 3-1½ V; (14) inner metatarsal tubercle present, oval; outer metatarsal tubercle absent; (15) iris bicolored; (16) dorsal surfaces golden-yellow with sparse golden-orange speckling or reticulations and few small dark-brown spots; (17) lateral sides of head and body with wide dark reddish-brown to black lateral stripes, clearly separated from lighter dorsal coloration by straight contrasting edge; (18) ventral surfaces of body, throat, and chest greyish-blue with indistinct brown confluent blotches; (19) upper eyelids with few (3-5) very small flat reddish superciliary tubercles; (20) limbs dorsally reddish-brown, ventrally brown with small bluish-white speckles. The new species is also distinct from all congeners in 12S rRNA to 16S rRNA mitochondrial DNA fragment sequences (uncorrected genetic distance P>8.9%). Advertisement call and tadpole morphology of the new species are described. Our molecular data showed Theloderma auratum sp. nov. to be a sister species of Th. palliatum from Langbian Plateau in southern Vietnam.

The first record over the period of study of the local fauna of snakes of the genus Gloydius in the Republic of Sakha (Yakutia) is described. We analyzed the literature data as well as the records of pit vipers confirmed by voucher specimens and photographs from the territory east of Lake Baikal — in the Far East of the Russian Federation (Primorskyi Krai, Khabarovsk Krai, and Amur Oblast, Sakhalin Oblast and Chita Oblast). Earlier the first reliable record of snakes of the genus Gloydius ( G. ussuriensis ) in the north of the Chita Oblast on the Ingoda River (Orlov et al., 2014; ZISP 28004 — 28008) was discovered. The first records of G. halys in the Lena River basin and its tributary Olekma River on the territory of the Republic of Sakha (Yakutia) are described in this paper. These data principally change existing ideas about the distribution of snakes in East Asia.

A new species of small tree frog from a primary montane tropical forest of central Vietnam, Tay Nguyen Plateau, is described based on morphological, molecular, and acoustic evidence. The Golden Bug-Eyed Frog, Theloderma auratum sp. nov., is distinguishable from its congeners and other small rhacophorid species based on a combination of the following morphological attributes: (1) bony ridges on head absent; (2) smooth skin completely lacking calcified warts or asperities; (3) pointed elongated tapering snout; (4) vocal opening in males absent; (5) vomerine teeth absent; (6) males of small body size (SVL 21.8–26.4 mm); (7) head longer than wide; ED/SVL ratio 13%–15%; ESL/SVL ratio 16%–20%; (8) small tympanum (TD/EL ratio 50%–60%) with few tiny tubercles; (9) supratympanic fold absent; (10) ventral surfaces completely smooth; (11) webbing between fingers absent; (12) outer and inner metacarpal tubercles present, supernumerary metacarpal tubercle single, medial, oval in shape; (13) toes half-webbed: I 2–2¼ II 1½–2¾ III 2–3¼ IV 3–1½ V; (14) inner metatarsal tubercle present, oval; outer metatarsal tubercle absent; (15) iris bicolored; (16) dorsal surfaces golden-yellow with sparse golden-orange speckling or reticulations and few small dark-brown spots; (17) lateral sides of head and body with wide dark reddish-brown to black lateral stripes, clearly separated from lighter dorsal coloration by straight contrasting edge; (18) ventral surfaces of body, throat, and chest greyish-blue with indistinct brown confluent blotches; (19) upper eyelids with few (3–5) very small flat reddish superciliary tubercles; (20) limbs dorsally reddish-brown, ventrally brown with small bluish-white speckles. The new species is also distinct from all congeners in 12S rRNA to 16S rRNA mitochondrial DNA fragment sequences (uncorrected genetic distance P>8.9%). Advertisement call and tadpole morphology of the new species are described. Our molecular data showed Theloderma auratum sp. nov. to be a sister species of Th. palliatum from Langbian Plateau in southern Vietnam.

Here we describe the tadpoles of Theloderma gordoni. These tadpoles can be distinguished from other members of the genus Theloderma by having the combination of the following characters: total length (50.1-54.5 mm, stages 28-33); tail shape (abdominal and dorsal fins with a gradual tapering toward the anterior and posterior portions, without an abrupt tapering in the posterior portion); number of marginal papillae in one row on the oral disc (51-55); degree of pigmentation (body dorsally and ventrally practically black, with a slight bluish tint). We also include a comparative analysis and thorough review of tadpole descriptions of other Theloderma.

The first documented record of Gloydius ussuriensis from the territory of Mongolia is described with reference to museum material. The description is based on a single specimen collected in the east of the country (Nomrog River). Data on morphological characteristics of the specimen and geographic distribution of this species are provided.

The record of Protobothrops cf. maolanensis in Trang Dinh district, Lang Son Province, northeastern Vietnam is discussed in the article. Data on locality and population biology is given. Description of morphology of eight specimens which originate from this locality, with brief taxonomic comments, is given.

Only one species of "Gloydius blomhoffii" complex - Gloydius ussuriensis was earlier known on the territory of the Russian Federation. The present paper discuss important new records of Gloydius blomhoffii blomhoffii (Boie, 1826) in the Kuril islands and the new data on the distribution of the forms of "Gloydius blomhoffii" complex within the territory of Russian Federation.

In this article we give an extended description of tadpoles of Theloderma bicolor and Theloderma corticale and present morphological differences between larval stages of these two closely related and parapatric species. Larvae of these two species clearly differ by their size (tadpoles of T bicolor are much smaller than tadpoles of T corticale at the same developmental stages), number of marginal papillae in one row (less in T bicolor than in T corticale) and tail shape.