Arthropod Systematics & Phylogeny 73(1): 107-128, doi: 10.3897/asp.73.e31820
Morphological and genetic data clarify the taxonomic status of Colossendeis robusta and C. glacialis (Pycnogonida) and reveal overlooked diversity
expand article infoLars Dietz, Sven Pieper, Meike A. Seefeldt, Florian Leese
‡ University of Duisburg-Essen, Essen, Germany
Open Access
Colossendeis robusta Hoek, 1881, originally described from the Kerguelen shelf, is considered as one of the most widespread Antarctic pycnogonids. However, the taxonomic status of this and similar species has long been unclear, as synonymy of C. glacialis Hodgson, 1907 and several other species with C. robusta has been proposed. Here we test the synonymy of C. robusta and C. glacialis with two independent molecular markers as well as comprehensive morphometric measurements and SEM data of the ovigeral spine configuration. We show that C. robusta and C. glacialis are clearly distinct species, and our results also indicate the existence of another previously unrecognized Antarctic species, C. bouvetensis sp.n., as well as an Antarctic lineage closely related to the endemic Kerguelen group C. robusta s.str. We find evidence for strong regional differentiation within each species. Our results suggest that diversity of Antarctic pycnogonids is still underestimated.
Colossendeis robusta, Colossendeis glacialis, Colossendeis bouvetensis, Southern Ocean, Pycnogonida, phylogeography, integrative taxonomy.