Molecular differentiation in sympatry despite morphological stasis: deep-seaAtlantoserolis Wägele, 1994 andGlabroserolis Menzies, 1962 from the south-west Atlantic (Crustacea: Isopoda: Serolidae)

Abstract

During DIVA-3, the third expedition of the DIVA project (Latitudinal gradients of deep-sea biodiversity in the Atlantic Ocean), 45 specimens of Serolidae were obtained from the Argentine Basin, at a depth of about 4600 m. These were a new species of Glabroserolis and Atlantoserolis vemae (Menzies, 1962). Besides the description of Glabroserolis occidentalis sp. nov., Glabroserolis specialis Menzies, 1962 is redescribed on the basis of the type material. Atlantoserolis vemae is redescribed using the type material, North Atlantic specimens, and the new South Atlantic material. Morphological differences between specimens of A. vemae from the North and South Atlantic could not be identified. The molecular data suggest that A. vemae from the Argentine Basin comprises two deeply divergent clades, which may represent reproductively isolated, sympatric species.

Recent speciation and hybridization in Icelandic deep-sea isopods: an integrative approach using genomics and proteomics

“…In the case of Haploniscus bicuspis , several genetically divergent lineages were recovered, of which some probably constitute separate, morphologically cryptic species. Commonly observed intraspecific COI distances within deep-sea isopods were usually below 6% (e.g., Brix, Riehl, & Leese, 2011;Brix et al, 2018aBrix et al, , 2018bHavermans et al, 2013;Brandt, Brix, Held, & Kihara, 2014;Bober, Riehl, Henne, & Brandt, 2018), but intraspecific distances of more than 8% have been reported (e.g., Riehl, Lins, & Brandt, 2018). Conversely, interspecific COI distances as low as 4.6% were reported (Riehl et al, 2018), possibly suggesting that some of the larger intraspecific distances may be due to cryptic diversity, but commonly exceed 10% (e.g., Havermans et al, 2013;Brandt et al, 2014;Brix et al, 2018aBrix et al, , 2018b.…”

Phylogenetic and functional evidence suggests that deep-ocean ecosystems are highly sensitive to environmental change and direct human disturbance

“…Trait groupings and traits were chosen based on ecological relevance and data availability. We used a fuzzy coding [47] [38]); Mysida ( pink branches): Heteromysis modlini (modified from [39]). (b) Functional dendrogram of 77 peracarid taxa sampled by box corer from the NW Atlantic Ocean.…”

“…Root at 600 Ma, concentric circles representing 50 Ma steps to present day (tips). Examples of taxa-Amphipoda (blue branches): Leucothoe rudicola (modified from[37]); Cumacea (yellow branches): Procampylaspis chathamensis (image & Sarah Gerken); Tanaidacea (red branches): Pseudosphyrapus anomalus (image & Graham J. Bird); Isopoda (green branches): Atlantoserolis vemae (modified from[38]); Mysida ( pink branches): Heteromysis modlini (modified from[39]). (b) Functional dendrogram of 77 peracarid taxa sampled by box corer from the NW Atlantic Ocean.…”

Rhachotropis (Eusiroidea, Amphipoda) from the North East Atlantic

“…We conclude that the two aff. helleri groups therefore either represent a single species, which contains widely-divergent COI sequence, or that the two clades may be two species, which are genuinely cryptic rather than pseudo-cryptic ( Janosik and Halanych 2010 ; Brandt et al 2014 ). Although there may be good reasons to flag potentially new species to attract further attention ( Wägele 1994 ), we do not propose the formal erection of a new species here because the aff.…”