The threatened Rufous Limestone Babbler Gypsophila calcicola—not a quarry species, but a “quarried species”

Summary Limestone karst habitats are threatened globally by quarrying for production of concrete and cement. A significant area of limestone karst shared among the provinces of Saraburi, Lopburi and Nakhon Ratchasima in Thailand encompasses the entire global range of a threatened bird taxon, the Rufous Limestone Babbler Gypsophila calcicola. We estimate that 10% of the suitable habitat for this species had already been lost to quarrying by 2020, and the extension of already proposed concessions could increase this to one-quarter, with the total area impacted by proposed future quarrying as great as 273 km2, or one and a half times greater than the entire area thought to support the species, within a few years. Only 2.66 km2 (1.4% of the species’ range) has received formal habitat protection as national park. We propose further surveys of the babbler be incorporated as part of a wider biotic survey of the Saraburi Group Limestones, leading to the development of an integrated management and zoning plan that takes account of the distributional knowledge of other threatened endemic taxa of this region.

Origin, diversity, and conservation of karst-associated Bent-toed Geckos (Genus Cyrtodactylus) in Myanmar (Burma)

Fifty-eight percent of the 43 known species of the Bent-toed Geckos (Cyrtodactylus) from Myanmar are found only in karstic habitats in the Shan Plateau and Salween and Ayeyarwady basins. A stochastic character mapping analysis indicated that the occupation of karstic habitats evolved at least four times independently in Burmese lineages with both Sundaic and Indian origins. Karstic habitats not only serve as foci for speciation but are refugia for species extirpated from the surrounding forested habitats due to agricultural development. Despite the high levels of biodiversity and site-specific endemism in karstic habitats in Myanmar, they are some of the least protected ecosystems. The immense financial returns from unsustainable resource extraction (cement manufacturing) makes the challenge of legal karst conservation extremely difficult. Sadly, their continued exploitation for limestone shows no signs of abating. Until karst habitats in Myanmar are thoroughly investigated, a significant portion of this country’s herpetological diversity will remain underestimated and unprotected.

Composition and distribution characteristics of karst epilithic moss communities

Background Bryophytes have an important ecological function in maintaining ecological diversity, material transformation, and energy cycles in ecosystems. In this study, bryophytes in a typical karst area were the research objects. The coverage and abundance of rocky bryophytes in established plots were recorded. The composition and distribution characteristics of the karst epilithic mosses were analyzed by importance values, a dissimilarity index and ggplot2 in R. Results The karst epilithic moss communities included 207 species in 93 genera and 37 families, including 185 species in 27 families and 80 genera of mosses and 22 species in 10 families and 13 genera of liverworts. The dominant families were Pottiaceae, Brachytheciaceae, Thuidiaceae, Bryaceae, Hypnaceae, Mniaceae, Entodontaceae, and Lichenaceae. The dominant species were Thuidium kanedae, Pseudosymblepharis angustata, Trichostomum involutum, Racopilum cuspidigerum, Brachythecium helminthocladum, Eurohypnum leptothallum, Hyophila involuta, Anomodon rugelii, Taxiphyllum taxirameum, and Bryohaplocladium angustifolium. Epilithic mosses in karst habitats have five life forms: turf, weft, cushion, slanting, and pendant. The main life forms we observed were turf and weft. Conclusions The distribution of the epilithic moss communities is closely related to their habitats. The diversity of bryophytes in areas with high forest coverage, high humidity, and abundant water and heat conditions is higher than that of bryophytes in rocky desertification habitats.

Genomic Mechanisms of Physiological and Morphological Adaptations of Limestone Langurs to Karst Habitats

Knowledge of the physiological and morphological evolution and adaptation of nonhuman primates is critical to understand hominin origins, physiological ecology, morphological evolution, and applications in biomedicine. Particularly, limestone langurs represent a direct example of adaptations to the challenges of exploiting a high calcium and harsh environment. Here, we report a de novo genome assembly (Tfra_2.0) of a male François’s langur (Trachypithecus francoisi) with contig N50 of 16.3 Mb and resequencing data of 23 individuals representing five limestone and four forest langur species. Comparative genomics reveals evidence for functional evolution in genes and gene families related to calcium signaling in the limestone langur genome, probably as an adaptation to naturally occurring high calcium levels present in water and plant resources in karst habitats. The genomic and functional analyses suggest that a single point mutation (Lys1905Arg) in the α1c subunit of the L-type voltage-gated calcium channel Cav1.2 (CACNA1C) attenuates the inward calcium current into the cells in vitro. Population genomic analyses and RNA-sequencing indicate that EDNRB is less expressed in white tail hair follicles of the white-headed langur (T. leucocephalus) compared with the black-colored François’s langur and hence might be responsible for species-specific differences in body coloration. Our findings contribute to a new understanding of gene–environment interactions and physiomorphological adaptative mechanisms in ecologically specialized primate taxa.

A new species of Bent-toed Gecko (Squamata, Gekkonidae, Cyrtodactylus) from the Shan Plateau in eastern Myanmar (Burma)

An integrative taxonomic analysis of the Cyrtodactylus linnwayensis group of the Shan Plateau recovered two new populations from isolated karst habitats near Pinlaung Town, Shan State as a new species, C. pinlaungensis sp. nov. Cyrtodactylus pinlaungensis sp. nov. is most closely related to a clade comprising C. linnwayensis and C. ywanganensis from the western edge of the Shan Plateau approximately 90 km to the northwest. Cyrtodactylus pinlaungensis sp. nov. can be distinguished from all members of the C. linnwayensis group by a number of statistically different morphological characters, discrete color pattern differences, and its heavy tuberculation. It also bears an uncorrected pairwise sequence divergence of 5.0–7.6% from all other species combined based on the mitochondrial gene ND2 and its flanking tRNAs. The discovery of this new species on the Shan Plateau continues to underscore the fact that this region is rapidly emerging as a herpetological diversity hot-spot for Myanmar.

Uncovering karst endemism within Borneo: two new Cyrtodactylus species from Sarawak, Malaysia

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.