Siogamaia is a small genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of very small sea snail

Snail

Snail is a common name applied to most of the members of the molluscan class Gastropoda that have coiled shells in the adult stage. When the word is used in its most general sense, it includes sea snails, land snails and freshwater snails. The word snail without any qualifier is however more often...

s, pyramidellid

Pyramidellidae

Pyramidellidae, common name the pyram family, or pyramid shells, is a voluminous taxonomic family of mostly small and minute ectoparasitic sea snails, marine heterobranch gastropod molluscs or micromolluscs....

 gastropod mollusks or micromollusk

Micromollusk

A micromollusk is a descriptive term for a shelled mollusk which is extremely small, even at full adult size. The word is usually, but not exclusively, applied to marine mollusks, although in addition, numerous species of land snails and freshwater mollusks also reach adult size at very small...

s. This genus is currently placed in the subfamily Chrysallidinae

Chrysallidinae

Chrysallidinae is a taxonomic group of very small sea snails in the family Pyramidellidae.- Taxonomy :Chrysallidinae has been one of eleven recognized subfamilies of the gastropod family Pyramidellidae...

 of the family

Family (biology)

In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Odostomiidae. The genus was originally described as a subgenus of Tropaeas Dall & Bartsch, 1904, but was later erected to a full genus and placed within Chysallidinae by Schander et al. (1999).

Shell description

The original genus description (Nomusa 1936), states that Siogamaia is a shell of moderate size with many whorls. The outline is elongate-conical in outline. The surface is marked by weak axial ribs that are mostly shown in the earlier whorls. The interspaces between the ribs are smooth. The Aperture is obliquely ovate with a single distinct columellar fold. The outer lip is smooth within,

Life history

Nothing is known about the biology of the members of this genus. As is true of most members of the Pyramidellidae

Pyramidellidae

Pyramidellidae, common name the pyram family, or pyramid shells, is a voluminous taxonomic family of mostly small and minute ectoparasitic sea snails, marine heterobranch gastropod molluscs or micromolluscs....

 sensu lato, they are most likely to be ectoparasites.

Species

Species within the genus Siogamaia include:

• Siogamaia fortiplicata (Nomura, 1936) (Type species) (AsTropaeas (Siogamaia) fortiplicata)
• Siogamaia akatiperipherata Nomura, 1936
• Siogamaia asamusi Nomura, 1936
• Siogamaia desiderabilis Nomura, 1936
• Siogamaia kinkwazan Nomura, 1937
• Siogamaia morioria (Laws, 1941)
• Siogamaia minamotoi (Nomura, 1936)
• Siogamaia namensis (Corgan & Van Aartsen, 1998)
• Siogamaia odostomoides Nomura, 1937
• Siogamaia problematica (Nomura, 1936)
• Siogamaia quantoensis Nomura, 1937
• Siogamaia semiplicata (Turton, 1932)
• Siogamaia takonourana (Nomura, 1936)
• Siogamaia venus (Nomura, 1936)