To reveal the diversity of Indonesian bent-toed geckos, we pay attention to Kalimantan (Borneo)—an island which has received less attention than other Indonesian islands such as Sumatra, Java, Sulawesi, the Moluccas, and the Lesser Sunda archipelagos. About 30 years after Hikida (1990) described three new Cyrtodactylus from Borneo, four more species were described, namely C. limajalur and C. muluensis in 2019, and C. hantu and C. miriensis in 2021, all by Davis et al. Through examination of the collection at MZB and three addition specimens collected from Tawau, we found several undescribed species, one of which we describe here. This new species is easily differentiated from all other congeners by the combination of the following characters: maximum SVL of at least 65.8 mm; no tubercles on dorsal surface of upper arm; tubercles present in the ventrolateral body folds; 28–30 paravertebral tubercles; 17–20 longitudinal dorsal tubercle rows; 39–46 ventral scale rows at midbody; 17–19 subdigital lamellae on fourth toe; precloacal pit with 5–7 pores in males arranged in a wide Λ-shape but absent in females; no enlarged transverse median subcaudals; paired dark brown semilunar-shaped markings on the upper nape. Further study is needed to reveal its molecular phylogenetic position and biogeographical history.

Psammophis indochinensis Smith, 1943 was reported in the eastern Java and Bali of Indonesia despite its primary geographic range being in the Indochina region. We confirm its presence in Bali based on a newly collected specimen and provide morphological and genetic data. The specimen was found in a lowland, urban areas near open grassland habitat, which confirms the distribution of P. indochinensis along the northern coast of Bali. We note some character aberrations in the supralabials compared to Thailand specimens, suggesting an extended character. The basal clade position of P. indochinensis raises the possibility of an intercontinental dispersal scenario of this African-origin snake.

Cyrtodactylus marmoratus is originally described based on the specimen from Java. Due to the marbled body colour pattern and the similarity in morphology, many specimens from outside of Java have been identified as C. marmoratus. The ongoing research, both molecular and morphological studies, showed that C. marmoratus is restricted to Java. The taxonomic status of specimens labelled as C. marmoratus from outside Java remains unresolved. Here, we study the morphometric and meristic of Javan, Sumatran, and Kalimantan Cyrtodactylus which were labelled as C. marmoratus to reveal their taxonomic status. We examined 11 morphometric and 19 meristic characters in 51 specimens at Museum Zoologicum Bogoriense (MZB) originally from, Java, Sumatra, and Kalimantan labelled as C. marmoratus as well as other recognized species. Principal Component Analysis (PCA) results show that C. marmoratus from Java differs from previous specimens which labelled as C. marmoratus from Sumatra and Kalimantan. The PCA results also show that C. marmoratus from Martabe differs from C. marmoratus Java which is supported by statistical analysis on interorbital, HeadW, HeadD, tubercle on the ventrolateral fold, dorsal tubercle and ventral scales. We hypothesized that Cyrtodactylus from Martabe is a suspected undescribed species-await formal description, and overall molecular analyses are needed for future study.

The Indonesian archipelago is an ideal setting for the study of speciation and biogeography. This archipelago is divided into three island groups based on zoogeography: Sundaland, Wallacea and the Australian region. In this paper we used frogs in genus Fejervarya (Bolkay) to study biogeography and examine patterns of gene flow across proposed zoogeographic boundaries. Several molecular studies on Fejervarya species from Indonesia have been carried out, but comparative studies among members of the genus Fejervarya have yet to be performed. In order to elucidate genetic divergence and geographic distribution of these frogs, we conducted a molecular analysis of the mitochondrial 16S rRNA gene using 179 frogs from five Fejervarya species. In total we collected from 32 localities in Sumatra, Kalimantan (Indonesian part of Borneo), Java, Bali, Sulawesi and Lesser Sunda Islands in Indonesia. Molecular phylogenetic analysis recovered 35 haplotypes and showed that frogs in the genus Fejervarya were divided into two well-supported clades. The first group were of three species, F. limnocharis, F. iskandari and F. cf. verruculosa and the other group clade consisted of Fejervarya cancrivora and Fejervarya sp. (Sulawesi-type). The average sequence divergence among these four species ranged from 1.09 to 16.03% (mean = 11.29±2.83%). The present results clearly show that there are five Fejervarya species in the Indonesian archipelago. Fejervarya limnocharis and F. cancrivora are widely distributed and sympatric in Sumatra, Borneo and Java. Fejervarya iskandari is not endemic to Java and also occurs in the Lesser Sundas. Fejervarya cf. verruculosa and Fejervarya sp. (Sulawesi-type) are endemic to Lesser Sunda and Sulawesi Island, respectively.

The Indonesian island of Sumatra contains several endemic species of parachuting frog of the genus Rhacophorus. Most of these are known from small type series collected from only a few localities, and consequently, many Sumatran Rhacophorus species are poorly understood. Using mitochondrial DNA (mtDNA), we investigated relationships among a group of Rhacophorus species from southern Sumatra. Our molecular analysis was based on a fragment of the 16S ribosomal subunit gene (16S) and included data derived from type specimens of two species endemic to Sumatra: R. barisani and R. catamitus. Our analyses of these data reveal that the only known female specimen of R. catamitus possesses a divergent 16S sequence compared to male specimens (8.82%; uncorrected “p” distance). Based on phylogenetic reconstructions, we found that this female specimen belongs to an unnamed taxon related to R. margaritifer from Java. Consequently, we remove the specimen from R. catamitus and describe it as R. bengkuluensis sp. nov., a medium-sized slender tree frog with extensive brown hand webbing. We identified additional specimens referable to the new species using mtDNA and morphology. These specimens originate from low to intermediate elevations (ca. 600–1600 m) in the provinces of Bengkulu and Lampung, suggesting that R. bengkuluenis is widely distributed across the southwestern versant of the Bukit Barisan.

The bent-toed geckos of the genus Cyrtodactylus are the most speciose land vertebrates of Southeast Asia (about 300 species so far) and new species continue to be recognized at a rapid rate. Within the last decade three new species were described from Java, Indonesia, C. semiadii, C. petani, and C. klakahensis. The latter two are very similar, except for differences in the precloacal depression in adult males. These two species have relatively close type localities, separated from each other by only about 50 km, and with similar habitat type and elevation. Our study aimed to evaluate the taxonomic status of C. klakahensis and C. petani using both morphological and genetic evidence. These two species are genetically similar, with a genetic divergence of only 1.5 to 1.6%. This divergence is well below the level of typically characterizes sister species of Cyrtodactylus (approximately 4% in the mitochondrial ND2 gene), and is more in line with population variation due to geographic distance. Further examination of specimens, from both type localities, showed no diagnostic morphological characters between the two species. Thus, we conclude that C. klakahensis and C. petani are conspecific, and following article 23 of the ICZN, C. klakahensis is herein considered a junior synonym of C. petani.