At the edge and on the top: molecular identification and ecology of Daphnia dentifera and D. longispina in high-altitude Asian lakes

Abstract

The occurrence of members of the highly diverse Daphnia longispina complex in Southern and Central Asian high-mountain lakes has been recognized for more than a century. Until now, however, no molecular data have been available for these populations inhabiting the ''Roof of the World.'' Here, we present the first identification for D. gr. longispina from that region based on a molecular phylogeny. Our findings show that alpine lakes in the Pamir and Himalaya mountains host populations of widespread species of the complex, for which these are the highest known localities. A spineless morph from the Himalaya region, previously labeled as D. longispina var.aspina, was clustering tightly with D. dentifera, while a population from the Pamir mountain range was grouped with D. longispina. In addition, we analyzed ecological data available for lakes in the Khumbu region (Himalaya) to investigate ecological preferences of non-pigmented D. gr. longispina. The identified factors can at least partly be related to avoidance of high UV conditions by this species. We conclude that the widespread species D. dentifera and D. longispina also colonized the Asian high-mountain lakes, and identify the need for further research to trace the possible effect of rapid environmental changes in this region on the diversity and ecology of high-altitude Daphnia populations.

Daphnia diversity on the Tibetan Plateau measured by DNA taxonomy

“…The Daphnia longispina complex was found in eight water bodies from the westernmost Ngari Prefecture to Lhasa River. The lineage of D. longispina was found in Bangong co and Lang co, Ngari area, western Tibet, near to the recently confirmed easternmost locality of Pamir Mountains (Möst et al., ). Its distribution extends to western China.…”

“…More recently, Möst et al. () and Ma et al. () used DNA sequences to study species diversity in the region.…”

“…These were updated after several scientific expeditions to the area during the 1970s (Chiang & Chen, 1974;Chiang, Shen, & Gong, 1983). More recently, Möst et al (2013) and Ma et al (2015) used DNA sequences to study species In this study, we employed DNA barcoding and DNA taxonomy through analysis of the mitochondrial marker COI to determine species diversity of the Daphnia genus in lakes and ponds on the Tibetan Plateau. We also estimated the number of endemic species in the region and generated a phylogenetic tree based on our mtCOI data and those from GenBank.…”

Biogeography of the ‘water flea’ Daphnia O. F. Müller (Crustacea: Branchiopoda: Anomopoda) on the Indian subcontinent

“…2 a and b, respectively). It was demonstrated earlier that these taxa prefer high altitudes (Manca et al, 1994(Manca et al, , 1998(Manca et al, , 2006Möst et al, 2013;Ma et al, 2015). …”

pH as a key factor defining the niche space of the alpine crustacean species Daphnia tanakai

“…Daphnia , a filter‐feeding crustacean zooplankton, is a key player in lentic water and species such as Daphnia pulex , Daphnia longispina , and Daphnia galeata often occur abundantly and dominate zooplankton communities in lowland and subalpine zones (Winder et al ; Bigler et al ; Möst et al ). Although an alpine lentic body of water is an environmentally harsh habitat as mentioned above, some Daphnia species exclusively occur in such an environment.…”