Lantern Shells of the Thraciidae Family
Two Lantern Shells of the Thraciidae Family can be found in this website:
Phylogeny: Lantern Shells of the Thraciidae Family (Stoliczka, 1870), are in the phylum Mollusca and the class Bivalvia. They are in the subclass Autobranchia, the infraclass Heteroconchia, the subterclass Euheterodonta, the superorder Anomalodesmata, and the superfamily Thracioidea. The Thraciidae Family is one of four families in this superfamily. The Thraciidae Family contains seventeen genera and ninety-four species. The name Thraciidae comes from the Greek words referring to the ancient region of Thrace, where shells from this family were found. The common name Lantern Shells comes from these shells’ resemblance to an oil lamp or lantern. Species in the Thraciidae Family are also known as Thracid Clams.
Description: Lantern Shells may be quadrate, ovate, or round in outline. They are inflated in profile, with the right valve usually more convex than the left. The left valve often fits within the right valve. These shells are thin and brittle. The anterior end may be narrowly to broadly rounded. The posterior end may be truncate or bluntly rostrate. The exterior of these shells may be smooth, pustulate, striated, or sculpted with commarginal ridges or undulations. The interior is non-nacreous. Some species have a projecting resilifer. The margins are smooth. The anterior adductor scar is elongate and the posterior scar is round. The pallial sinus may be shallow or deep. Shells in this family are generally whitish. They have a thin periostracum that may be translucent to dark brown. Lantern Shells are small to medium in size, with the largest species reaching a maximum of 9.0 cm (3.5 inches) in length.
Habitat and Distribution: Lantern Shells are generally found buried in fine to coarse sand or mud substrates, but some species nestle in rock crevices. They range from the intertidal zone to depths of, at least, 836 m (2,742 feet). Lantern Shells are found worldwide in polar to tropical seas. Eleven species from the Thraciidae Family are found in Mexican waters.
Natural History: Lantern Shells are suspension feeders that filter plankton and fine detritus from the surrounding water. In turn they are preyed upon by birds, crabs, carnivorous mollusks and rays. They maybe gonochoric or simultaneous hermaphrodites. They reproduce sexually, through broadcast spawning, with external fertilization. Lantern Shells have not historically been the target of commercial or recreational fishers, or aquaculture.