Morphological and taxonomic demarcation of Brachionus asplanchnoidis Charin within the Brachionus plicatilis cryptic species complex (Rotifera, Monogononta)

作者：Michaloudi Evangelia^*; Mills Scott; Papakostas Spiros; Stelzer Claus Peter; Triantafyllidis Alexander; Kappas Ilias; Vasileiadou Kalliopi; Proios Konstantinos; Abatzopoulos Theodore John

来源：Hydrobiologia, 2017, 796(1): 19-37.

DOI：10.1007/s10750-016-2924-2

• Brachionus plicatilis
• Brachionus asplanchnoidis
• Brachionus 'Nevada'
• Brachionus 'Austria'
• Brachionus manjavacas
• Rotifer
• Morphology
• Species delimitation

Three well-defined groups, consisting of 15 species, have recently been ascribed to organisms historically identified as the Brachionus plicatilis species complex. One of these groups, the large clade, is composed of two named species (Brachionus plicatilis s.s. and Brachionus manjavacas) and two species identifiers (B. 'Nevada' and B. 'Austria'). B. 'Austria' has been confirmed to be B. asplanchnoidis. As no type specimen exists for this species, and the original taxonomic description is lacking in detail, we give a detailed account of this species using material from Obere Halbjochlacke in Austria where B. 'Austria' was first identified genetically. Our analysis of B. asplanchnoidis populations was of global scope, an approach that revealed a great degree of morphological variability. However, combining aspects of both the dorsal and ventral surfaces clearly discriminated B. asplanchnoidis from the rest of the large-type members. This approach may prove useful in taxonomic studies of other cryptic species with relatively few morphological features. We also observed a geographic pattern of genetic divergence within B. asplanchnoidis. Average uncorrected COI divergences for a 554-bp fragment of the COI gene ranged from 3.9% within species to 17.5% between species of the large clade and indicate deep divisions within the cryptic species complex.

• 出版日期2017-7