Chaban E.M.1, Ekimova I.A.2*, Chernyshev A.V.3 2024. Philinopsis gigliolii (Gastropoda: Heterobranchia: Aglajidae) from the Sea of Japan: validity, synonymy and biogeography // Invertebrate Zoology. Vol.21. No.2: 157–169 [in English].
1 Marine Research Laboratory, Zoological Institute, Russian Academy of Sciences, Universitetskaya emb. 1, St. Petersburg 199034 Russia.
2 Invertebrate Zoology Department, Lomonosov Moscow State University, Leninskie gori 1-12, Moscow 119234 Russia.
3 A.V. Zhirmunsky National Scientific Center of Marine Biology, Far Eastern Branch, Russian Academy of Sciences, Palchevskogo str. 17, Vladivostok 690041 Russia.
* Corresponding author
Elena Chaban echaban@zin.ru ORCID 0000-0002-3433-5736
Irina Ekimova irenekimova@gmail.com ORCID 0000-0002-1846-0780
Alexey Chernyshev nemertea1969@gmail.com ORCID 0000-0002-2203-3001
doi: 10.15298/invertzool.21.2.04
ABSTRACT: Philinopsis gigliolii (Tapparone Canefri, 1874) was described under the name Aglaja gigliolii based on preserved material from the Pacific coast of Japan, collected during an expedition of the Italian warship Magenta in 1864–1868. Currently, this species is considered a subjective synonym of P. speciosa Pease, 1860, described from Hawaii, despite their morphological differences. To clarify the species status of P. gigliolii we have conducted a molecular phylogenetic analysis of the genus Philinopsis using COI, 16S, and histone H3 molecular markers, which included a specimen of P. gigliolii from Peter the Great Bay, the Sea of Japan. Our results confirm that P. gigliolii represents a distinct valid species, which shows both morphological and molecular differences with P. speciosa. The latter species is recovered paraphyletic and clearly needs further taxonomical revision. At the same time, the molecular analysis indicates that Australian species P. taronga (Allan, 1933) is conspecific to P. gigliolii (only two molecular substitutions were identified in 16S), and these species show many similarities in both external and internal morphology. We consider P. taronga a junior subjective synonym of P. gigliolii. Formally Chelidonura aureopunctata Rudman, 1968, described from New Zealand, is considered a junior subjective synonym of P. gigliolii as well. Philinopsis gigliolii has an antitropical distribution, its range includes subtropical and temperate areas of the Pacific Ocean in both hemispheres (the Sea of Japan, the Yellow Sea, the Pacific coast of Japan; South-East Australia and the northern coast of New Zealand). Three hypotheses may explain this distribution pattern. (1) The antitropical distribution results from the historical disjunction across tropical latitudes following the abiotic or biotic factors. (2) Philinopsis gigliolii may be widely distributed in temperate and tropical waters of the Pacific Ocean but be overlooked in the central part of its geographic range due to external similarities to other species of the genus. (3) The last hypothesis suggests the anthropogenic transportation of P. gigliolii. Further sampling activity and comparative genetic analyses may contribute to a better understanding of this very interesting biogeographic pattern.
KEY WORDS: Mollusca, Cephalaspidea, North-West Pacific, morphology, taxonomy, integrative analysis.