Vol. 64, 2025

Integrative Description of a New Freshwater Tardigrade Species, Dactylobiotus taiwanensis (Tardigrada: Eutardigrada: Murrayidae), Discovered Through Social Media

, EChih-Yu Pai², Reinhardt Møbjerg Kristensen³, and Daniel Stec^4,*

¹University of Catania, Department of Biological, Geological and Environmental Sciences, Section of Animal Biology, Via Androne 81, 95124, Catania, Italy. E-mail: daniele.camarda@phd.unict.it (Camarda)
²Ruey Long Industry co., LTD, 1 F., No. 247, Sec. 3, Datong Rd., Xizhi Dist., New Taipei City 22178, Taiwan. E-mail: chihyupai@gmail.com (Pai)
³Natural History Museum of Denmark, University of Copenhagen, DK-2100 Copenhagen Ø, Denmark. E-mail: rmkristensen@snm.ku.dk (Kristensen)
⁴Institute of Systematics and Evolution of Animals of the Polish Academy of Sciences, Sławkowska 17, 31-016 Kraków, Poland. *Correspondence: E-mail: daniel_stec@interia.eu (Stec)

urn:lsid:zoobank.org:pub:98CC3B62-CA99-40B9-A17E-2FC8756AE5CA
(Received 7 December 2024 / Accepted 8 March 2025 / Published 7 May 2025)
Communicated by Benny K.K. Chan

Two freshwater tardigrade populations belonging to the genus Dactylobiotus were investigated using phase contrast microscopy, scanning electron microscopy, and molecular markers commonly employed in tardigrade phylogenetic studies (18S rRNA, 28S rRNA, ITS2, and COI). The population from Taiwan, discovered through social media, represents a new species, described here as Dactylobiotus taiwanensis sp. nov. This species is most similar to Dactylobiotus parthenogeneticus but differs in the presence of singular rings of pores surrounding the egg processes and specific morphometric traits. The second population, from Greenland, was provisionally identified as D. cf. octavi, and its morphological discrepancies are discussed in detail. A revision of the type material for Dactylobiotus caldarellai and Dactylobiotus lombardoi raises questions about their validity due to insufficient data. Finally, a phylogenetic analysis incorporating taxa from the family Murrayidae, along with the newly sequenced populations, is presented. An updated dichotomous key for the genus Dactylobiotus is also provided.

Keywords: Meiofauna, Taxonomy, Freshwater, Egg ornamentation, New species

Citation: Camarda D, Pai CY, Kristensen RM, Stec D. 2025. Integrative description of a new freshwater tardigrade species, Dactylobiotus taiwanensis (Tardigrada: Eutardigrada: Murrayidae), discovered through social media. Zool Stud 64:14. doi:10.6620/ZS.2025.64-14.

Supplementary materials: SM. 1丨SM. 2丨SM. 3丨SM. 4丨SM. 5