The half leaf-fingered geckos (Hemiphyllodactylus) are a diverse group with more than 70 recognized species and a distribution range from southern India and Sri Lanka, through Indochina and Southeast Asia, to the western Pacific region.
As a result of its cryptic lifestyle and small body size, its diversity had been neglected until a recent surge of integrative taxonomic research, which combines different lines of evidence, most importantly molecular and morphological data.
Over the last ten years, more than 60 members of the genus (~85% of its diversity) have been newly described. Vietnam is a hot spot for new species discoveries with at least 10 congeners uncovered in recent years, including H. banaensis, H. bonkowskii, H. cattien, H. dalatensis, H. lungcuensis, H. nahangensis, H. ngocsonensis, H. vanhoensis, H. yenchauensis, and H. zugi.
A newly published paper in ZooKeys reveals another new species within Hemiphyllodactylus, Hemiphyllodactylus ziegleri, from Copia Nature Reserve, Son La Province, northwestern Vietnam. The new species is currently known only from this protected area, established in 2002. Although its range is estimated at less than 50 km², the area has been experiencing severe habitat degradation, primarily as a result of road construction and timber logging.
The new species honours Prof. Dr. Thomas Ziegler, a world-class herpetologist and conservation biologist of Cologne Zoo and the University of Cologne, who has made remarkable contributions to biodiversity research and conservation in Southeast Asia, especially to its the herpetofauna. Prof. Ziegler was involved in the descriptions of seven Hemiphyllodactylus species from Vietnam.
In addition to his more than three decades of engagement in taxonomic and ecological studies – spanning lizards, snakes, turtles, salamanders, frogs, and other vertebrates and invertebrates – Prof. Ziegler has made substantial contributions across herpetology broadly.
More recently, he has actively developed in-situ and ex-situ conservation measures to safeguard some of Vietnam’s most endangered species, including the Crocodile Lizard (Shinisaurus crocodilurus), the Vietnamese Knobby Newt (Tylototriton vietnamensis), the Cat Ba Leopard Gecko (Goniurosaurus catbaensis), and the Vietnamese Pond Turtle (Mauremys annamensis).
As for Hemiphyllodactylus, the current taxonomy is believed to substantially underestimate its diversity, especially in the karst ecosystem, as recent discoveries demonstrate that this particular habitat harbors a high number of cryptic species.
Coinciding with the publication of H. ziegleri, another karst-dwelling species - H. pakhaensis from Son La Province - was reported in ZooKeys. These discoveries bring the total species count to 12, suggesting that additional surveys in remote areas of the country and elsewhere in Southeast Asia will likely reveal many new congeners and highlight the importance of this unique, but highly imperiled ecosystem.
Original sources
Pham AV, Nguyen TQ, Pham CT, Ngo HT, Le MD (2026) Hemiphyllodactylus ziegleri sp. nov. (Squamata, Gekkonidae), a new karst-dwelling gecko species from Son La Province, Vietnam. ZooKeys 1268: 75-94. https://doi.org/10.3897/zookeys.1268.174678
Ha HB, Hoang TT, Nguyen MD, Ha NV, Luu VQ (2026) A new species of Hemiphyllodactylus Bleeker, 1860 (Squamata, Gekkonidae) from Son La Province, Vietnam. ZooKeys 1268: 163-188. https://doi.org/10.3897/zookeys.1268.177040