Anton Chichvarkhin

Phylogeny and Evolution of Butterflies of the Genus Parnassius: Inferences from Mitochondrial 16S and ND1 Sequences

Abstract Phylogenetic relationships among species of the genus Parnassius and its related taxa were analyzed by comparing nucleotide sequences of mitochondrial 16S ribosomal RNA (504 sites) and NADH-dehydrogenase subunit 1 (469 sites). In the phylogenetic trees, Parnassius was found to be most closely related to Hypermnestra helios, whereas Archon apollinus, which has been classified in the tribe Parnassiini together with Parnassius and Hypermnestra, was more closely related to members of the tribe Zerynthiini. Within the Parnassius clade, six major clades corresponding to species groups were well supported, although the phylogenetic relationships among them were not clear. Although the results of the present study were in agreement with those of a previous phylogenetic study based on mitochondrial NADH-dehydrogenase subunit 5 sequences, our study strongly supported a close relationship between Parnassius and Hypermnestra, which was not well supported in the previous study.

A Radical Solution: The Phylogeny of the Nudibranch Family Fionidae

Tergipedidae represents a diverse and successful group of aeolid nudibranchs, with approximately 200 species distributed throughout most marine ecosystems and spanning all biogeographical regions of the oceans. However, the systematics of this family remains poorly understood since no modern phylogenetic study has been undertaken to support any of the proposed classifications. The present study is the first molecular phylogeny of Tergipedidae based on partial sequences of two mitochondrial (COI and 16S) genes and one nuclear gene (H3). Maximum likelihood, maximum parsimony and Bayesian analysis were conducted in order to elucidate the systematics of this family. Our results do not recover the traditional Tergipedidae as monophyletic, since it belongs to a larger clade that includes the families Eubranchidae, Fionidae and Calmidae. This newly recovered clade is here referred to as Fionidae, the oldest name for this taxon. In addition, the present molecular phylogeny does not recover the traditional systematic relationships at a generic level, and therefore, systematic changes are required. We recognize the following clades within Fionidae: Calma, Cuthona, Cuthonella, Eubranchus, Fiona, Murmania, Tenellia, Tergipes, Tergiposacca gen. nov., Rubramoena gen. nov. and Abronica gen. nov. The type species of Tergiposacca, T. longicerata nov. sp. is described. The other two new genera have a previously described species as their type species. Most of these taxa, with the exceptions of Eubranchus, Tergipes and Fiona are composed of radically different constituent species from their traditional membership, but appear to be supported by morphological synapomorphies as well as molecular data. Aenigmastyletus, Catriona, Phestilla, Tenellia and Trinchesia are nested within other clades and, thus are here considered as synonyms of the larger clades. The phylogenetic position and validity of Myja, Guyvalvoria, Leostyletus and Subcuthona still need to be tested in future studies when material becomes available.

Aligning evidence: concerns regarding multiple sequence alignments in estimating the phylogeny of the Nudibranchia suborder Doridina

Molecular estimates of phylogenetic relationships rely heavily on multiple sequence alignment construction. There has been little consensus, however, on how to properly address issues pertaining to the alignment of variable regions. Here, we construct alignments from four commonly sequenced molecular markers (16S, 18S, 28S and cytochrome c oxidase subunit I) for the Nudibranchia using three different methodologies: (i) strict mathematical algorithm; (ii) exclusion of variable or divergent regions and (iii) manually curated, and examine how different alignment construction methods can affect phylogenetic signal and phylogenetic estimates for the suborder Doridina. Phylogenetic informativeness (PI) profiles suggest that the molecular markers tested lack the power to resolve relationships at the base of the Doridina, while being more robust at family-level classifications. This supports the lack of consistent resolution between the 19 families within the Doridina across all three alignments. Most of the 19 families were recovered as monophyletic, and instances of non-monophyletic families were consistently recovered between analyses. We conclude that the alignment of variable regions has some effect on phylogenetic estimates of the Doridina, but these effects can vary depending on the size and scope of the phylogenetic query and PI of molecular markers.

A new phoronid species, Phoronis embryolabi, with a novel type of development, and consideration of phoronid taxonomy and DNA barcoding

Abstract. The Phoronida, which is one of the smallest phyla of invertebrates, includes only 13 valid species, although ∼40 larval forms of phoronids were recently described. This report uses light microscopy and molecular methods to describe a new phoronid species, Phoronis embryolabi Temereva & Chichvarkhin, sp. nov. The morphology of P. embryolabi, which lives commensally in the burrows of Axiidea shrimp Nihonotrypaea japonica in Vostok Bay (the Sea of Japan), is extremely similar to that of Phoronis pallida Silen, 1952; the bodies of both species exhibit specific regionalisation. However, the organisation of the metanephridia differs between P. pallida and P. embryolabi. Moreover, P. embryolabi has a unique type of development, viviparity, in which mothers release fully developed larvae into the environment. In all other phoronid species, the spawning occurs as a release of fertilised eggs or early embryos. Viviparity of completely developed larvae has not been previously described for any phoronid. According to analysis of partial 28S rRNA, P. embryolabi is close to Phoronis pallida. On the other hand, analysis of partial cytochrome c oxidase subunit I indicated a unique position of P. embryolabi among phoronids. These results should be used for revision of phoronid taxonomy (i.e. the type of development should be considered as characteristic of subgenera within the genus Phoronis). This report also establishes the relationship between P. embryolabi and an Actinotrocha sp. that was described in a previous paper.

Shallow water sea slugs (Gastropoda: Heterobranchia) from the northwestern coast of the Sea of Japan, north of Peter the Great Bay, Russia

The coast of northern Primorye region, north of Peter the Great Bay has been sparsely studied in regards to its molluscan fauna, with just a few works reviewing the distribution of local mollusks. This work presents a survey of the shallow water heterobranch sea slugs currently occurring around Kievka Bay to Oprichnik Bay, Russia. Thirty-nine species of sea slugs were found in this study and the new species Cadlina olgae sp. nov., described herein. Most (24) of the species occurring in the area have widespread ranges in the northern Pacific Ocean. The eight species are endemic for the Sea of Japan and adjacent part of the Sea of Okhotsk. Seven other occur also in northern Atlantic and Arctic waters. Thirteen found species are not known from Peter the Great Bay but known from adjacent northern Pacific waters. The finding of a previously undescribed species emphasizes the need of further surveys, particularly in subtidal and deeper waters, in order to improve the knowledge on this neglected fauna in Primorye.

A New Cryptic Species of Melanochlamys (Gastropoda: Heterobranchia: Cephalaspidea) from the Northwestern Pacific

Abstract: A new species of Melanochlamys is described based on specimens collected in Russia and Korea. This new species is genetically and anatomically different from other North Pacific species. Phylogenetic analyses of two mitochondrial (COI, 16S) and a nuclear (H3) gene confirmed the results of previous analyses and recovered a clade including specimens of the new species. Although this clade is poorly supported, species delimitation analyses and anatomical differences confirmed it constitutes a distinct species. These results confirm the presence of two distinct species of Melanochlamys in Russia and Korea, bringing the total diversity of the genus in the North Pacific to five.

Henricia djakonovi sp. nov. (Echinodermata, Echinasteridae): a new sea star species from the Sea of Japan

A new sea star species, H. djakonovi sp.n., was discovered in Rudnaya Bay in the Sea of Japan. This is a sympatric species of the well-known and common species Henricia pseudoleviuscula Djakonov, 1958. Both species are similar in body size and proportions, shape of skeletal plates, and life coloration, which distinguishes them from the other Henricia species inhabiting the Sea of Japan. Nevertheless, these species can be distinguished by their abactinal spines: in both species, they are short and barrel-like, but the new species is the only Henricia species in Russian waters of the Pacific that possesses such spines with a massive, smooth, bullet-like tip. The spines in H. pseudoleviuscula are crowned with a variable number of well-developed thorns. About half (<50%) of the abactinal pseudopaxillae in the new species are oval, not crescent-shaped as in H. pseudoleviuscula.

Sea star Henricia spiculifera (Clark, 1901) in the northwestern Pacific: one species or three?

Three species of the sea stars are reported from the waters of the northwestern Pacific. These species were referred by earlier authors as Henricia spiculifera or H. leviuscula spiculifera. Two of them, H. lineata and H. uluudax, were recently described from the Aleutian Islands. These species are reported for the first time from the western Pacific (southeastern Kamchatka shore, Commander Islands, and the northern Kurile Islands). The third species, H. olga sp. n. is herein described from the northern Sea of Japan. It is very likely that similar sea stars recorded in Yellow Sea and the southern Kurile Islands belong to H. olga sp. n. These three species are a part of a phylogenetic clade within the subgenus Setihenricia, which also includes H. sanguinolenta, H. multispina, and several undescribed species occurring in the northeastern Pacific.