Scaling the high latitudes: evolution, diversification, and dispersal of Coryphella nudibranchs across the Northern Hemisphere.

Nudibranch molluscs Coryphella are widely distributed and species-rich gastropod group lacking fossil record and displaying a complex distribution across both Southern and Northern hemispheres. In this paper we provide a detailed review of the morphology, ecology, and distribution of Coryphella, estimation of divergence times between species, an ancestral area reconstruction, and a population analysis of widely distributed trans-Arctic species Coryphella verrucosa to investigate the evolution, phylogeographic patterns and reconstruct possible historical routes of oceanic dispersal. The inclusion of a larger sample size and five molecular markers has revealed a complex evolutionary history of Coryphella, shaped by transgression, vicariance, and dietary shifts, and overall driven by the pervasive effect of glacial cycles.

Panmixia and local endemism: a revision of the species complex with a description of new species.

Species of the genus Eubranchus Forbes, 1838 (Mollusca: Gastropoda: Nudibranchia) are common faunistic elements of boreal benthic ecosystems, associated with hydroid communities. Recent studies have suggested that the widely distributed trans-Arctic E. rupium (Møller, 1842) constitutes a complex of at least three candidate species, but the detailed taxonomy of the complex remains unresolved.

(Ceriantharia: Anthozoa: Cnidaria): New Status and New Perspectives.

Subclass Ceriantharia is a well-defined and probably ancient group of marine benthic organisms renowned for their bilateral symmetry, which is reflected in the arrangement of tentacles and mesenteries. Four species of Ceriantharia have been reported in the Arctic, including Gosse, 1859, also known from the Northern Atlantic and Northern Pacific. The integrity of this species was questioned in the literature, so we performed a molecular study of from several geographically distant locations using 18S and COI genes.

Nematocyst sequestration within the family Fionidae (Gastropoda: Nudibranchia) considering ecological properties and evolution.

Aeolid nudibranchs are well-known for their ability to incorporate cnidarian nematocysts and use them for defense; this process is tightly linked with the feeding preferences of molluscs. As many nudibranch groups show signs of ecology-based adaptive radiation, studies of prey-based defensive mechanisms can provide valuable insight into details of nudibranch evolutionary history. The main goal of this study is to test the correlation of ecological traits, feeding mechanisms, and prey preferences with cnidosac fine morphology and to pinpoint the phylogenetic value of these traits.

Diet-driven ecological radiation and allopatric speciation result in high species diversity in a temperate-cold water marine genus Dendronotus (Gastropoda: Nudibranchia).

While the majority nudibranch clades are more species rich in the tropics, the genus Dendronotus is mainly represented in Arctic and boreal regions. This distribution pattern remains poorly understood. An integrative approach and novel data provided valuable insights into processes driving Dendronotus radiation and speciation.