Convergence in communication appears rare compared with other forms of adaptation. This is puzzling, given communication is acutely dependent on the environment and expected to converge in form when animals communicate in similar habitats. We uncover deep-time convergence in territorial communication between two groups of tropical lizards separated by over 140 million years of evolution: the Southeast Asian Draco and Caribbean Anolis. These groups have repeatedly converged in multiple aspects of display along common environmental gradients. Robot playbacks to free-ranging lizards confirmed that the most prominent convergence in display is adaptive, as it improves signal detection. We then provide evidence from a sample of the literature to further show that convergent adaptation among highly divergent animal groups is almost certainly widespread in nature. Signal evolution is therefore curbed towards the same set of adaptive solutions, especially when animals are challenged with the problem of communicating effectively in noisy environments.
The island of Borneo lies within one of the most biodiverse regions in the world. Despite this, its documented gekkonid diversity is not commensurate with other areas of Southeast Asia. The megadiverse genus Cyrtodactylus is especially underrepresented. Limestone-karst ecosystems, in particular, harbor many endemic Cyrtodactylus species, but only one karst-dwelling species is currently recognized from Borneo. This paper adds two additional karst-dwelling Cyrtodactylus species-C. muluensis sp. nov. and C. limajalur sp. nov.-from Sarawak, Malaysia. Cyrtodactylus muluensis sp. nov. is endemic to Gunung Mulu and is distinguished from its congeners by having a precloacal groove, 31-38 ventral scales, a maximum SVL of at least 88 mm, enlarged subcaudals, 19-20 subdigital lamellae, and a banded dorsal body pattern. Cyrtodactylus limajalur sp. nov. is endemic to the Serian region and is distinguished from its congeners by having 33-42 ventral scales, enlarged subcaudals, a precloacal pit, a maximum SVL of at least 94 mm, 5-6 enlarged femoral scales, 19-22 subdigital lamellae, and five distinct bands on the dorsum. Both species are phylogenetically distinct and deeply divergent from all other congeners. The description of two new karst-dwelling species highlights the need to conserve karst habitats and the endemic species they harbor.
We describe a new species of Cyrtodactylus on the basis of four specimens collected from the limestone karst forest of Phu Yen District, Son La Province, Vietnam. Cyrtodactylus sonlaensis sp. nov. is distinguished from the remaining Indochinese bent-toed geckos by a combination of the following characters: maximum SVL of 83.2 mm; dorsal tubercles in 13-15 irregular rows; ventral scales in 34-42 rows; ventrolateral folds prominent without interspersed tubercles; enlarged femoral scales 15-17 on each thigh; femoral pores 14-15 on each thigh in males, absent in females; precloacal pores 8, in a continuous row in males, absent in females; postcloacal tubercles 2 or 3; lamellae under toe IV 18-21; dorsal head with dark brown markings, in oval and arched shapes; nuchal loop discontinuous; dorsum with five brown bands between limb insertions, third and fourth bands discontinuous; subcaudal scales distinctly enlarged. In phylogenetic analyses, the new species is nested in a clade consisting of C. huongsonensis and C. soni from northern Vietnam and C. cf. pulchellus from Malaysia based on maximum likelihood and Bayesian analyses. In addition, we record Cyrtodactylus otai Nguyen, Le, Pham, Ngo, Hoang, Pham & Ziegler for the first time from Son La Province based on specimens collected from Van Ho District.
Effective communication requires animal signals to be readily detected by receivers in the environments in which they are typically given. Certain light conditions enhance the visibility of colour signals and these conditions can vary depending on the orientation of the sun and the position of the signaller. We tested whether Draco sumatranus gliding lizards modified their position relative to the sun to enhance the conspicuousness of their throat-fan (dewlap) during social display to conspecifics. The dewlap was translucent, and we found that lizards were significantly more likely to orient themselves perpendicular to the sun when displaying. This increases the dewlap's radiance, and likely, its conspicuousness, by increasing the amount of light transmitted through the ornament. This is a rare example of a behavioural adaptation for enhancing the visibility of an ornament to distant receivers.
We describe Cyrtodactylus psarops sp. nov. and C. semicinctus sp. nov., two new species of bent-toed geckos from montane forests in the southern Bukit Barisan Range of Sumatra, Indonesia. The new species are closely related to one another and to C. semenanjungensis, a lowland species currently known only from Peninsular Malaysia. Three characters of the new species immediately distinguish them from most congeners in the Sunda Region: they lack transversely enlarged subcaudals, have a precloacal depression, and have a greatly enlarged scale positioned at the apex of a continuous series of femoral and precloacal pore-bearing scales. They differ from one another in cephalic pattern, tuberculation of the brachium, and in numbers of cloacal tubercles, dorsal bands, and ventrals in a transverse row. The greatly enlarged scale at the apex of the precloacal pores appears to be a rare apomorphy of these two species and C. agamensis.
A new species of scincid lizard, Lipinia sekayuensis sp. nov. from Hutan Lipur Sekayu, Terengganu State in northeastern Peninsular Malaysia is most similar to L. surda (Boulenger) but differentiated from it and all other species of Lipinia by having the combination of an adult SVL of 42.3 mm; six supralabials; five infralabials; four supraoculars; prefrontals widely separated; two loreals; fused frontoparietals; lower eyelids bearing a large, transparent disc; 21 midbody scale rows; 56 paravertertebral scale rows; 65 ventral scale rows; enlarged, precloacal scales; 10 subdigital lamellae on the third finger; 11, 15, and seven lamellae on the third, fourth, and fifth toes, respectively; distal subdigital lamellae keeled; a median row of slightly enlarged, subcaudal scales present; a generally unicolor, dark-brown dorsum bearing nine very faint, diffuse, darker stripes; and an external ear opening replaced by a scaly, auditory depression.
Matched MeSH terms: Lizards/anatomy & histology; Lizards/classification*; Lizards/growth & development
An integrative taxonomic analysis of three newly discovered populations of the gekkonid genus Cyrtodactylus Gray from Merapoh, Pahang; Gunung Stong, Kelantan; and Gunung Tebu, Terengganu indicate they are part of the C. pulchellus complex and each is a new species and thusly named Cyrtodactylus sharkari sp. nov., C. jelawangensis sp. nov., and C. timur sp. nov., respectively. Each species bears a unique suite of morphological and color pattern characters separating them from each other and all other nominal species in the C. pulchellus complex. Their phylogenetic relationships to each other and other species in the C. pulchellus complex were unexpected in that they are not in accordance with the general distribution of the species in this complex, underscoring the intricate historical biogeography of the Thai-Malay Peninsula. These descriptions highlight our current lack of knowledge concerning the herpetological diversity and distribution of species in northeastern Peninsular Malaysia.
A new species of lowland karst dwelling Cnemaspis Strauch 1887, C. grismeri sp. nov. is described from the southeastern base of the Banjaran Bintang in northern Peninsular Malaysia. It is differentiated from its congeners by a unique combination of characters including size, coloration and scalation. Cnemapis grismeri sp. nov. is most closely related to C. mcguirei, an upland species endemic to the Banjaran Bintang. This phylogeographic pattern is also seen in the upland and lowland Banjaran Bintang species of Cyrtodactylus bintangtinggi and C. bintangrendah, respectively (Grismer et al. 2012). The discovery of yet another endemic gekkonid in the poorly explored karst regions of Peninsular Malaysia underscores the necessity for concentrated collecting efforts in these unique landscapes.
Matched MeSH terms: Lizards/anatomy & histology; Lizards/classification*; Lizards/growth & development
The snake genus Cylindrophis Wagler, 1828 belongs to the monogeneric family Cylindrophiidae comprising 15 species distributed predominately throughout SE Asia, with one extralimital species occurring in Sri Lanka (Bernstein et al. 2020: 535). Cylindrophis lineatus is a rare species known from only eight museum specimens (discussed herein), and a photograph of one live individual from Kuching, Sarawak, East Malaysia (Stuebing et al. 2014: 63). Despite being originally described with Singapore as the type-locality (Blanford 1881: 217, 218), it is currently understood that C. lineatus is endemic to western Sarawak, East Malaysia (Stuebing et al. 2014: 63). Wallach et al. (2014: 204) stated that C. lineatus is also found in Kalimantan, but did not provide any references. This appears to have been followed by Bernstein et al. (2020: 537), who provide a map indicating C. lineatus occurrences in Kalimantan. The original description of Cylindrophis lineatus is conventionally cited as Blanford (1881: 217, 218, pl. 20). Herein, we demonstrate that the authorship and date of publication of this taxon should correctly be Cylindrophis lineatus Dennys, 1880b, and discuss that the type locality should be changed to "Borneo".
A herpetological survey was conducted at Pulau Besar, Melaka from 10 to 12 June 2008, resulting in the discovery of five species of amphibians, nine species of lizards (including one new species of the gekkonid Cyrtodactylus) and one snake species. This report constitutes the first checklist of the herpetofauna of Pulau Besar and the Water Islands Archipelago.
An integrative taxonomic analysis is used to delimit and describe three new species of Pseudocalotoes from the sky island archipelago of the Banjaran (=mountain range) Titiwangsa of Peninsular Malaysia. Pseudocalotes drogon sp. nov., from Fraser's Hill, Pahang is basal to the sister species P. larutensis from Bukit Larut, Perak in the Banjaran Bintang and the new species P. rhaegal sp. nov. from Cameron Highlands, Pahang. Pseudocalotes drogon sp. nov. is differentiated from all other species of Psuedocalotes by having the combination of a flat rostrum; seven postrostrals; an interparietal; 11 circumorbitals; five canthals; 7-10 superciliaries; one scale between the rostral and nasal; nine supralabials; eight infralabials; 10 postnasal-suborbital scales; four postmentals; five or six sublabials; five or six chinshields; 47 smooth, wide, gular scales; weak transverse gular and antehumeral folds; two enlarged scales between the ear and eye; enlarged upper and lower posttemporals; a single enlarged supratympanic; no enlarged postrictals; three large scales bordering the dorsal margin of the ear opening; large pretympanic scales; eight scales in the nuchal crest not separated by a gap; enlarged vertebral scales extending to the tip of the tail; keeled and non-plate-like scales on flanks; 51 midbody scales; midventrals smaller than dorsals; 19 subdigital lamellae on the fourth finger; 23 subdigital lamellae on the fourth toe; preaxial scales on third toe enlarged and spinose; subdigital lamellae not unicarinate; HW/HL 0.52; HL/SVL 0.31; no elbow or knee patches; and a male dewlap color of lime-green bearing a central yellow spot. Pseudocalotes rhaegal sp. nov. is differentiated from all other Psuedocalotes by having the combination of a convex rostrum; 6-8 postrostrals; an interparietal; nine or 10 circumorbitals; five canthals; 7-10 superciliaries; one or two scales between the rostral and nasal scales; eight or nine supralabials; seven or eight infralabials; 11 or 12 postnasal-suborbital scales; four postmentals; four or five chinshields; 40-45 smooth, wide, gular scales; no transverse gular fold; a weak antehumeral fold; three or four enlarged scales between the ear and eye; an enlarged upper and lower posttemporal; an enlarged supratympanic; no enlarged postrictals; no large scales bordering the upper margin of the ear opening or in the pretympanic region; 6-8 enlarged nuchal crest scales not separated by a gap; enlarged vertebral scales extending to the base of the tail; weakly keeled, non-plate-like scales on the flanks; 52-58 midbody scales; midventrals smaller than dorsals; 19-21 subdigital lamellae on the fourth finger; 22-26 subdigital lamellae on the fourth toe; preaxial scales on the third enlarged and rounded; subdigital lamellae not unicarinate; HW/HL 0.50-0.54; HL/SVL 0.28-0.30; no elbow or knee patches; and female dewlap color yellow bearing a purple base. The analyses also indicated that the new species, P. viserion sp. nov. from Genting Highlands, Pahang in the southern section of the Banjaran Titiwangsa is the sister species of P. flavigula from Cameron Highlands 121 km to the north and can be separated from all other species of Psuedocalotes by having the combination of three postrostrals; 10 circumorbitals; four or five canthals; 5-7 superciliaries; rostral and nasals in contact; supralabials contacting the nasal; six or seven supralabials; six or seven infralabials; two or three postmentals; 47 or 48 smooth, flat, gular scales; three chinshields; weak transverse gular and antehumeral folds; two enlarged scales between the ear and eye; an enlarged upper and lower posttemporal; an enlarged supratympanic; no enlarged postrictals; 7-9 nuchal crest scales lacking gaps and not extending beyond midbody; weakly keeled and plate-like scales on the flanks; 35-38 midbody scales; ventrals smaller than dorsals; 22 or 23 subdigital lamellae on the fourth finger; 26 or 27 subdigital lamellae on the fourth toe; preaxial scales on the third toe not modified; subdigital scales not unicarinate; HW/HL 0.62; no white marking below the eye; dewlap in males yellow; and no elbow or knee patches. Pseudocalotes rhaegal sp. nov. most likely occurs in syntopy with P. flavigula in Tanah Rata at Cameron Highlands and its discovery adds to a growing body of literature detailing the recent descriptions of several new, upland, closely related, sympatric species in Peninsular Malaysia. Another new population referred to here as Pseudocalotes sp. nov. from the Hala-Bala Wildlife Sanctuary, Betong District, Yala Province, Thailand is discussed. The discovery and description of these three new Pseudocalotes from the upland regions of Peninsular Malaysia continues to underscore the remarkably high herpetological diversity and ecological complexity in this sky island archipelago that is still underestimated, unappreciated, and unprotected.
Matched MeSH terms: Lizards/anatomy & histology; Lizards/classification*; Lizards/growth & development
We describe two new species of skinks from Gunung Penrissen, Sarawak, Malaysia, in northern Borneo, Tytthoscincus batupanggah sp. nov. and T. leproauricularis sp. nov. Morphological and molecular analyses both corroborate the two new species as unique compared to all other Tytthoscincus and additional Sphenomorphus that are candidates for taxonomic placement in the genus Tytthoscincus. Despite their phenotypic similarity and sympatric distribution, a molecular analysis shows that the new species are not sister taxa and exhibit a deep genetic divergence between each of their respective sister taxa. We discuss how historical climatic and geographic processes may have led to the co-distribution of two relatively distantly related phenotypically similar species. In light of these discoveries, we also emphasize the importance of conserving primary montane tropical rainforest for maintaining species diversity.
Matched MeSH terms: Lizards/anatomy & histology; Lizards/classification*; Lizards/growth & development
A new species of Bent-toed Gecko, Cyrtodactylus gunungsenyumensis sp. nov. of the sworderi complex, is described from Hutan Lipur Gunung Senyum, Pahang, Peninsular Malaysia and is differentiated from all other species in the sworderi complex by having a unique combination of characters including a maximum SVL of 74.7 mm; low, rounded, weakly keeled, body tubercles; 34-40 paravertebral tubercles; weak ventrolateral body fold lacking tubercles; 38-41 ventral scales; an abrupt transition between the posterior and ventral femoral scales; 20-23 subdigital lamellae on the fourth toe; enlarged femoral scales; no femoral or precloacal pores; no precloacal groove; wide caudal bands; and an evenly banded dorsal pattern. Cyrtodactylus gunungsenyumensis sp. nov. is a scansorial, karst forest-adapted specialist endemic to the karst ecosystem surrounding Gunung Senyum and occurs on the vertical walls of the limestone towers as well as the branches, trunks, and leaves of the vegetation in the associated karst forest. Cyrtodactylus gunungsenyumensis sp. nov. is the seventh species of karst forest-adapted Cyrtodactylus and the sixteenth endemic species of karst ecosystem reptile discovered in Peninsular Malaysia in the last seven years from only 12 different karst forests. This is a clear indication that many species remain to be discovered in the approximately 558 isolated karst ecosystems in Peninsular Malaysia not yet surveyed. These data continue to underscore the importance of karst ecosystems as reservoirs of biodiversity and microendemism and that they constitute an important component of Peninsular Malaysia's natural heritage and should be protected from the quarrying interests of foreign industrial companies.
A new species of limestone cave-adapted gecko of the Cyrtodactylus pulchellus complex, C. hidupselamanya sp. nov., is described from an isolated karst formation at Felda Chiku 7, Kelantan, Peninsular Malaysia. This formation is scheduled to be completely quarried for its mineral content. From what we know about the life history of C. hidupselamanya sp. nov., this will result in its extinction. A new limestone forest-adapted species, C. lenggongensis sp. nov., from the Lenggong Valley, Perak was previously considered to be conspecific with C. bintangrendah but a re-evaluation of morphological, color pattern, molecular, and habitat preference indicates that it too is a unique lineage worthy of specific recognition. Fortunately C. lenggongensis sp. nov. is not facing extinction because its habitat is protected by the UNESCO Archaeological Heritage of the Lenggong Valley due to the archaeological significance of that region. Both new species can be distinguished from all other species of Cyrtodactylus based on molecular evidence from the mitochondrial gene ND2 and its flanking tRNAs as well as having unique combinations of morphological and color pattern characteristics. Using a time-calibrated BEAST analysis we inferred that the evolution of a limestone habitat preference and its apparently attendant morphological and color pattern adaptations evolved independently at least four times in the C. pulchellus complex between 26.1 and 0.78 mya.
Sympatric species that initially overlap in resource use are expected to partition the environment in ways that will minimize interspecific competition. This shift in resource use can in turn prompt evolutionary changes in morphology. A classic example of habitat partitioning and morphological differentiation are the Caribbean Anolis lizards. Less well studied, but nevertheless striking analogues to the Anolis are the Southeast Asian Draco lizards. Draco and Anolis have evolved independently of each other for at least 80 million years. Their comparison subsequently offers a special opportunity to examine mechanisms of phenotypic differentiation between two ecologically diverse, but phylogenetically distinct groups. We tested whether Draco shared ecological axes of differentiation with Anolis (e.g., habitat use), whether this differentiation reflected interspecific competition, and to what extent adaptive change in morphology has occurred along these ecological axes. Using existing data on Anolis, we compared the habitat use and morphology of Draco in a field study of allopatric and sympatric species on the Malay Peninsula, Borneo and in the Philippines. Sympatric Draco lizards partitioned the environment along common resource axes to the Anolis lizards, especially in perch use. Furthermore, the morphology of Draco was correlated with perch use in the same way as it was in Anolis: species that used wider perches exhibited longer limb lengths. These results provide an important illustration of how interspecific competition can occur along common ecological axes in different animal groups, and how natural selection along these axes can generate the same type of adaptive change in morphology.
During 3 collecting expeditions between October 1996 and December 1996, fecal samples were obtained from 43 adult Gonocephalus grandis from Tanah Rata and the Cameron Highlands in Peninsular Malaysia. Two species of coccidia (Isospora gonocephali n. sp. [9/43, 23%] and Eimeria cameronensis n. sp. [3/43, 7%]) were discovered. Sporulated oocysts of I. gonocephali are subspherical to ovoidal, 22.3 x 18.7 (19-25 x 17-23) microm with a bilayered wall composed of a thin inner wall and a striated outer wall with a pitted surface; oocyst residuum absent; 1 polar granule present; sporocysts are almond-shaped, 13.5 x 9.2 (12-15 x 8.5-10) microm, Stieda body broad, domelike, substieda body fanlike, sporocyst residuum consisting of coarse, nonuniform granules in an amorphous cluster; sporozoites sausage-shaped with 1 large terminal, refractile body and lay randomly in the sporocyst. Sporulated oocysts of E. cameronensis are bilayered, smooth-walled, ellipsoidal, 26.5 x 12.4 (25-28 x 12-13) microm; with 1, small, polar granule composed of 2-3 splinter-like structures fused together; oocyst residuum absent; sporocysts ovoidal, almost rectangular-shaped 8.8 x 6.6 (8-9 x 5-7) microm, with no Stieda or substieda bodies, containing scattered residuum and 2 sausage-shaped sporozoites with 1 terminal, ovoidal refractile body. No individual lizard was host to both coccidian species.
A Giardia varani Lavier, 1923-like flagellate was found in the feces of a captive water monitor, Varanus salvator, originally caught wild from an unknown location in Malaysia. The parasite is similar in size and shape to Giardia lamblia, except that median bodies are rare and cysts are binucleate. A description of both the trophozoite and cyst stage of this flagellate is provided.
Nest predation is the main cause of hatching failure for many turtle populations. For green turtles (Chelonia mydas) nesting at Chagar Hutang in Redang Island, Malaysia, Asian water monitors (Varanus salvator) are a potential nest predator. However, no studies have documented the space use of this species in coastal habitat adjacent to a sea turtle nesting beach to assess its potential impact on turtle nests. Here, we used Global Positioning System (GPS) data loggers to quantify space use of Asian water monitors in order to establish the extent to which they use sea turtle nesting areas. Asian water monitors had a diurnal activity pattern and spent most of their time in rain forest habitat behind the sea turtle nesting beach. The home range occupied by Asian water monitors varied between 0.015 and 0.198 km2 calculated by the Kernel Brownian Bridge method. The space use patterns of individual Asian water monitors varied between individuals. Two males had relatively small home ranges, whereas one male and the female had a relatively large home range. Because tracked Asian water monitors in this study rarely visited the sea turtle nesting areas, it is probable that only a few individuals are responsible for opening nests.
Eight strains of a lizard Leishmania species, L. tarentolae, were compared with four other saurian species [L. hoogstrali, L. adleri, L. agamae and Leishmania sp. LizS], with L. major from man and with Trypanosoma platydactyli, a putative lizard trypanosome, in terms of kinetoplast DNA minicircle and maxicircle sequences and in terms of nuclear chromosome patterns on orthogonal gel electrophoresis. The L. tarentolae strains fell into two major groups, one (group A) consisting of the L. tarentolae strains, UC, Krassner and Trager, derived from an Algerian gecko isolate and the other (group B) consisting of five L. tarentolae LEM strains isolated from geckos in southern France. T. platydactyli TPCL2, which was postulated by Wallbanks et al. to represent the lizard form of a French L. tarentolae strain, was closely related to the UC strain and not to the LEM strains, in all respects analyzed. Leishmania sp. LizS from a Mongolian gecko and L. hoogstrali from a Sudanese gecko showed some sequence similarities to the L. tarentolae strains, but the leishmanias said to be L. adleri from a Kenyan lacertid and L. agamae from an Israeli agamid showed no minicircle sequence similarities with lizard Leishmania and in fact were probably the same species. The maxicircle divergent region was larger in the group B strains than in the group A strains, but there were sequences in common with both groups, and not with L. hoogstrali and L. major. Four strains of L. tarentolae, the four other supposed saurian Leishmania species, three mammalian leishmanias, T. platydactyli and four other trypanosomes, T. cyclops (Malaysian macaque), T. conorrhini (Hawaiian reduviid bug), T. cruzi (man) and T. lewisi (feral rat) were analyzed for their contents of sterols and phosphoglyceride fatty acyl groups. T. platydactyli TPCL2 contained a sterol (5-dehydroepisterol), a phosphatidylcholine fatty acyl group (alpha-linolenic acid) and a phosphatidylethanolamine fatty acyl group (dihydrosterculic acid) characteristic of members of the genus Leishmania and not the genus Trypanosoma. The proportions of those lipids in the free sterol and phosphoglyceride fractions of T. platydactyli TPCL2 most closely resembled those seen in the Leishmania strains from Algerian, French, Mongolian and Sudanese geckos.
Lizards and snakes (squamates) are known for their varied sex determining systems, and gecko lizards are especially diverse, having evolved sex chromosomes independently multiple times. While sex chromosomes frequently turnover among gecko genera, intrageneric turnovers are known only from Gekko and Hemidactylus. Here, we used RADseq to identify sex-specific markers in two species of Burmese bent-toed geckos. We uncovered XX/XY sex chromosomes in Cyrtodactylus chaunghanakwaensis and ZZ/ZW sex chromosomes in Cyrtodactylus pharbaungensis. This is the third instance of intrageneric turnover of sex chromosomes in geckos. Additionally, Cyrtodactylus are closely related to another genus with intrageneric turnover, Hemidactylus. Together, these data suggest that sex chromosome turnover may be common in this clade, setting them apart as exceptionally diverse in a group already known for diverse sex determination systems.