Species ID
OC-SP-0002289
Discovered
Phylum
Mollusca
Species ID
OC-SP-0002289
Provisional Species Name
Aequiyoldia sp_MNHNCL MOL 101661
Lowest Valid Taxon Name in WoRMS
Aequiyoldia
Lowest Known Rank
Genus
Status
Discovered
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Embargo
No
Kingdom
Animalia
Phylum
Mollusca
Class
Bivalvia
Order
Nuculanida
Family
Sareptidae
Genus
Aequiyoldia
Date Identified
01/02/2026
Taxonomic Remarks
External shell morphology within Aequiyoldia is broadly conservative, and species are often superficially similar in overall outline and sculpture. Nevertheless, Aequiyoldia sp. nov. can be distinguished from its closest congeners by a consistent set of characters. Aequiyoldia sp. nov. differs from A. eightsii by its generally smaller shell length and by the shape of the pallial sinus, which is distinctly V-shaped in the new species, whereas in A. eightsii the pallial sinus is typically U-shaped. In addition, Aequiyoldia sp. nov. differs from A. woodwardii by its greater shell inflation, with valves noticeably more tumid than in A. woodwardii, which is comparatively more compressed.
Received All Minimal Data for Discovery
05/03/2026
Description of Material
Shell of moderate size (), subovate, compressed, thick, and slightly gaping anteriorly; white. The anterior end is slightly longer than the posterior end, which is somewhat pointed; margins rounded. The posterior dorsal margin is slightly concave, sometimes unusually pronounced. Periostracum yellowish green in juveniles, becoming dark brown in larger specimens, darker toward the ventral margin; occasionally with darker concentric bands. Umbones very weakly inflated, generally eroded. Beaks small, opisthogyrate. Sculpture composed of fine growth lines and faint radial lines, more evident at the anterior and posterior ends. Chondrophore triangular. Resilium almost entirely internal, externally divided into an anterior and a posterior portion relative to the chondrophore, the anterior portion being larger. Inner surface of the valves white and glossy, dorsally thickened toward the posterior region. Hinge with two subequal series of strong teeth; in the examined specimen, the anterior series presents 10 teeth and the posterior series 7 teeth. Pallial line weak; pallial sinus anteriorly subrounded and deep, reaching up to the level of the chondrophore, and posteriorly acute, V-shaped. Siphonal muscle scars small and faint, located ventral and posterior to the adductor scar.
Ecology
Habitat: Soft bottoms (mud and sandy mud), sometimes among glacial pebbles/cobbles; recorded from very shallow water (<10 m) to deeper shelf/upper slope settings. Ecology: Feeds mainly on organic material present in the surface layers of the sediment.
Distribution
Known only from the Magallanes Region (southern Chile).
Scientific Name Authorship
Rosenfeld
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