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| Pyropelta artemis Chen, Tsuda & Watanabe, 2025 |
Abstract
Hydrothermal vents and other chemosynthetic ecosystems are island-like oases in the deep ocean where microbial primary production supports an unusually high biomass. The small lepetelloidean family Pyropeltidae, with its sole genus Pyropelta containing about 10 described species, specialises in these systems. In the northwestern Pacific two species have been named around Japan, but their ranges have remained uncertain as shells of Pyropelta are typically corroded and difficult to identify morphologically. Here, we collected Pyropelta from three vents and two seeps in the northwestern Pacific, and assess the distribution of each species using molecular barcoding of the mitochondrial cytochrome c oxidase subunit I (COI) gene. As a result, we greatly extend the known distribution ranges of the two known northwestern Pacific species P. yamato and P. ryukyuensis. A lineage found in the Off Hatsushima seep in Sagami Bay was genetically distinct from the two described species and is named as Pyropelta artemis sp. nov. This new species inhabits a variety of substrates including tubes of siboglinid polychaetes as well as snail and mussel shells, and is noteworthy in displaying a great variability in its shell form because the aperture is constricted by substrate morphology. Our findings show that pyropeltids can also ‘shape-shift’ according to the substrate like many other limpet-formed gastropods, which excludes shell shape as a broadly useful taxonomic character in this family.
Keywords: cold seep; hydrothermal vent; Mollusca; Off Hatsushima; Pyropeltidae; Sagami Bay
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| In situ image of the type locality of Pyropelta artemis sp. nov. in the Off Hatsushima hydrocarbon seep, Sagami Bay, Japan, showing a range of substrate types where the new species was found living on – especially visible are the thick worm tubes of Lamellibrachia, narrow and twisted worm tubes of Alaysia, and shells of bathymodioline mussels. |
Pyropelta artemis sp. nov.
Etymology: Artemis – ‘she who shoots arrows’ – the goddess of the Moon and the hunt in Greek mythology. We allude to the new species’ capacity to ‘shape-shift’ in shell form, likening it to the moon’s waxing and waning. Used as a noun in apposition.
Chong Chen, Miwako Tsuda, and Hiromi Kayama Watanabe. 2025. Distribution of the Deep-Sea Limpet Genus Pyropelta in the Northwestern Pacific, with the Description of a New Species. Contributions to Zoology. 94(4); 371–394. DOI: doi.org/10.1163/18759866-bja10083
