Xenophorids are unusual in that in many of the species the animal cements small stones or shells to the edge of the shell as it grows, thus the shells of those species are sometimes humorously referred to as "shell-collecting shells". The genus name Xenophora comes from two ancient Greek words and means "bearing (or carrying) foreigners".
The shells are small to rather large (diameter of base without attachments 19–160 mm; height of shell 21–100 mm), depressed to conical, with narrow to wide, simple to spinose peripheral edge or flange separating spire from base. Aperture large, base broad, rather flattened, often umbilicate. Periostracum very thin or wanting. Protoconch depressed-conical, multispiral (in one species paucispiral). Teleoconch usually with foreign objects attached in spiral series to peripheral flange and, sometimes, remainder of dorsum, at least on early whorls. Operculum horny, yellowish to brown, nucleus lateral, with simple growth lamellae, sometimes with conspicuous radial striae or hollow radial ribs.[1]
Classification
Xenophoridae belongs to the superfamily Stromboidea, which also includes the true conchs (Strombidae).[2] It had previously been placed in a monotypic superfamily, Xenophoroidea,[3] but placement in Stromboidea is supported by behavioral,[4] anatomical,[5] and genetic data.[6] Within Stromboidea, Xenophoridae appears to be most closely related to Aporrhaidae and Struthiolariidae.[6]
Xenophora Fischer von Waldheim, 1807[10] - type genus
Behavior
Like other stromboids, xenophorids move in a "leaping" manner.[4]Xenophora conchyliophora has been found to move an average of 233.5 cm per day, with its speed during short-duration "sprints" averaging 1.44 cm per minute and reaching a maximum speed of 5.5 cm per minute.[11]
Xenophorids incorporate shells, coral, and other objects into their shells as they grow. Several different hypotheses have been proposed to explain this behavior.[12]
References
^ abcKreipl, K. & Alf, A. (1999): Recent Xenophoridae. 148 pp. incl. 28 color plts. ConchBooks, Hackenheim, ISBN3-925919-26-0.
^ abIrwin, Alison R.; Strong, Ellen E.; Kano, Yasunori; Harper, Elizabeth M.; Williams, Suzanne T. (2021). "Eight new mitogenomes clarify the phylogenetic relationships of Stromboidea within the caenogastropod phylogenetic framework". Molecular Phylogenetics and Evolution. 158: 107081. doi:10.1016/j.ympev.2021.107081. ISSN1055-7903. PMID33482382. S2CID231687470.
^Berg, Carl J. (1975). "Behavior and ecology of conch (Superfamily Strombacea) on a deep subtidal algal plain". Bulletin of Marine Science. 25 (3): 307–317.
^Feinstein, Noah; Cairns, Stephen D. (1998). "Learning from the collector: a survey of azooxanthellate corals affixed by Xenophora (Gastropoda: Xenophoridae), with an analysis and discussion of attachment patterns". The Nautilus. 112 (3): 73–83.
External links
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