Scyllaeidae represents a small clade of dendronotoid nudibranchs. Notobryon wardi Odhner, 1936, has been reported to occur in tropical oceans from th

Astonishing diversity revealed: an annotated and illustrated inventory of Nudipleura (Gastropoda: Heterobranchia) from Mozambique

The subfamily Polycerinae includes four genera with around 46 species described to date. This subfamily is characterized by a limaciform body, which may have simple tentacular processes on the margin of the oral veil. Phylogenetic relationships between the genera of the subfamily Polycerinae (Polyceridae) have not yet been studied, and therefore, the only available information is based on morphological descriptions. The present study reports the first phylogenetic analysis of Polycerinae based on the mitochondrial genes cytochrome oxidase subunit I and the large ribosomal subunit (16S rRNA) using maximum likelihood and Bayesian methods. Our results showed that Polycerinae is monophyletic, but the relationships within the subfamily as well as within Polycera remain unresolved. A key finding of this study is that there are clearly two sympatric species of Polycera present in South Africa: Polycera capensis Quoy and Gaimard, 1824 also found in Australia and an undescribed Polycera sp. On the other hand, the studied specimens of the genus Gymnodoris were clustered within Polycerinae, reopening the problem of the systematic position of this genus. Additional genes and species of Polycerinae and Gymnodoris would provide more information and probably fully resolve this situation.

To investigate the conspecificity of different morphotypes of Jorunna tomentosa (Cuvier, 1804) (type species of genus Jorunna Bergh, 1876), we studied specimens sampled from across part of the geographical distribution of the species, using a combination of morphoanatomical characters and molecular phylogenetics. Bayesian and maximum likelihood phylograms were inferred based on the mitochondrial genes cytochrome c oxidase subunit I (COI) and 16S ribosomal RNA, and the nuclear gene histone H3. We used the automatic barcode gap discovery method to aid in species delimitation. COI genetic uncorrected p-distances were estimated between and within species. Animals were dissected and the reproductive system, radulae and labial cuticles were examined; scanning electron microscopy was employed to study ultrastructural elements of anatomical characters. The results revealed the presence of a new species (Jorunna artsdatabankia n. sp.) and a possible case of incipient speciation in J. tomentosa with our COI data indicating the presence of two morphoanatomically indistinct lineages that are separated from each other by distances of 3.2–5.0%. The genetic distance between J. artsdatabankia n. sp. and its sister species J. tomentosa was 9.0–12.3%; the former species is characterized by a plain white to yellow background colour with irregularly placed small brown spots, smooth radular teeth and a longer vas deferens, wider vagina and a longer copulatory spine (up to 600 μm longer) than the latter. A diagnostic comparison of all species of European Jorunna is included, as well as a discussion of the assignment of J. lemchei to the genus Gargamella.