The little Aplysia coming of age: from one species to a complex of species complexes in Aplysia parvula (Mollusca: Gastropoda: Heterobranchia)

Abstract

The widespread sea hare species Aplysia parvula includes four genetically distinct lineages, containing a total of ten different species. While the four lineages can be differentiated by their external characteristics, species in each clade are often morphologically indistinguishable. A review of literature and type material revealed that several available names exist for species recognized herein: Aplysia parvula is retained for a species from the north-eastern Atlantic; A. atromarginata, A. elongata, A. nigrocincta and A. japonica are resurrected for species from the western Pacific Ocean, the Hawaiian Islands, the Indian and western Pacific Oceans, and Japan and Korea, respectively. Two new species names are introduced for animals from the eastern Pacific, and the Atlantic and Indian Oceans. Mitochondrial sequences from Mediterranean and eastern Atlantic specimens identified as A. parvula, resulted to be A. punctata. However, two specimens were heterozygotes of histone H3 alleles of A. punctata and of a new Atlantic species described herein, suggesting they could be hybrids. These results contradict the hypothesis that the Mediterranean was colonized by A. parvula. If an invasion occurred, it was a limited introgression of nDNA from an Atlantic species into native A. punctata populations.

An updated inventory of sea slugs from Koh Tao, Thailand, with notes on their ecology and a dramatic biodiversity increase for Thai waters

“…Distribution. Across the Indo-Pacific including Mozambique, Mauritius, the Philippines, Indonesia, Papua New Guinea, Vanuatu (Golestani et al 2019), Maldives (Yonow 1994 as Aplysia fasciata), and the Red Sea as Aplysia cf. parvula.…”

Genetic Evidence Confirms That the Porostomate Nudibranch Dendrodoris gunnamatta Allan, 1932 Is a Morphotype of Dendrodoris krusensternii (Gray, 1850) (Gastropoda: Nudibranchia)

“…This approach, which uses a range of discriminatory characters, provides strong support for taxonomic decisions. In most cases, integrated taxonomic methods are used to separate species within cryptic complexes resulting in increased species diversity [31,32]. However, in this paper, these methods have been used to identify morphological variation within a single species that resulted in their historical description as separate species.…”

Review of heterobranch molluscs fauna in the Boka Kotorska Bay, Montenegro

“…This species has a cosmopolitan distribution. According to the new knowledge recently published by GOLESTANI et al (2019) this species should be attributed to the taxon Aplysia punctata.…”