Ancyronyx clisteri, a new spider riffle beetle species from Borneo, redescription of A. sarawacensis Jäch including a description of the larva and new distribution data for A. procerus Jäch using DNA barcodes (Coleoptera, Elmidae)

Abstract

Ancyronyx clisterisp. nov. (Coleoptera, Elmidae) a new spider riffle beetle discovered from northern Borneo (Brunei; Sabah and Sarawak, Malaysia) and the larva of Ancyronyx sarawacensis Jäch are described. Illustrations of the habitus and diagnostic characters of the new species and the similar and highly variable A. sarawacensis are presented. Differences to closely related species, based on DNA barcodes and morphological characters, are discussed. Association of the larva and the imago of A. sarawacensis, and the occurrence of Ancyronyx procerus Jäch in Peninsular Malaysia and Sabah are confirmed by using COI mtDNA sequences.

Figure 5 from: Kodada J, Jäch MA, Freitag H, Čiamporová-Zaťovičová Z, Goffová K, Selnekovič D, Čiampor Jr F (2020) Ancyronyx lianlabangorum sp. nov., a new spider riffle beetle from Sarawak, and new distribution records for A. pulcherrimus Kodada, Jäch & Čiampor based on DNA barcodes (Coleoptera, Elmidae). ZooKeys 1003: 31-55. https://doi.org/10.3897/zookeys.1003.55541

“…They mainly occur in primary or slightly degraded forests, although some specimens were sampled in secondary forests or forest remnants as well. Not any specimen was found in large, polluted rivers or at light traps placed near such rivers in the Kuching Division during our sampling in 2018 and 2019 (Kodada et al 2020). Ancyronyx lianlabangorum sp.…”

“…Mean genetic distances within species are shown in Table 2. More complex divergences for the two latter species were calculated on larger sample sizes from different populations studied by Kodada et al (2020). Surprisingly, 17 new sequences obtained from two widely separated, allopatric populations of the well-supported A. pulcherrimus clade, showed higher pairwise genetic distances ranging from 0.0% to 3.7%.…”

“…Borneo, the third-largest island of the world, possesses a very diverse fauna with numerous endemic species including riffle beetles (e.g., Kodada et al 2014Kodada et al , 2020Freitag et al 2018). Tragically, the primary forests of Borneo continually decrease together with their specific aquatic habitats, which are disappearing or deteriorating at an alarming rate (Faridah-Hanum et al 2018).…”

“…The macropterous Ancyronyx acaroides, A. malickyi, and A. procerus are good flyers and considered to be widespread in Southeast Asia (Jäch et al 2016); however, the taxonomic and distributional data have been confirmed at a molecular level for only A. procerus (Kodada et al 2020). The remaining four species seem to have restricted ranges and are obviously endemic to Borneo.…”

Ancyronyx lianlabangorum sp. nov., a new spider riffle beetle from Sarawak, and new distribution records for A. pulcherrimus Kodada, Jäch & Čiampor based on DNA barcodes (Coleoptera, Elmidae)

“…Borneo, the third-largest island of the world, possesses a very diverse fauna with numerous endemic species including riffle beetles (e.g., Kodada et al 2014 , 2020 ; Freitag et al 2018 ). Tragically, the primary forests of Borneo continually decrease together with their specific aquatic habitats, which are disappearing or deteriorating at an alarming rate ( Faridah-Hanum et al 2018 ).…”