Trona stercoraria

Description

The shells of these common cowries reach on average 50 - of length, with a minimum size of 26 mm and a maximum size of 97 mm. They are very variable in pattern and colour. The shape ranges from oval to rhomboidal. The surface is smooth and shiny, the basic color is bluish, greenish or greyish, but it can be completely dark brown or whitish. Normally there is a dense dark brown spotting on the dorsum. The wide margins are usually dark brown and the anterior and posterior canals end into well developed 'rostra'. The base may be purplish, light brown, pinkish or white, with a long and narrow aperture and long brown, beige or white fine teeth with brown spacing. The 'fossula' is considerably protruding.

Distribution

Trona stercoraria occurs in west Africa along Cape Verdes, Senegal, Guinea, Cameroon, Gabon, São Tomé Island, the Congo and Angola.

Habitat

These cowries usually live in shallow waters under large rocks.

Subspecies

• Trona stercoraria stercoraria (Linnaeus, 1758) (synonyms : Cypraea conspurcata Gmelin, J.F., 1791; Cypraea fasciata Gmelin, J.F., 1791; Cypraea gibba Gmelin, J.F., 1791; Cypraea ligata Röding, P.F., 1798; Trona cineracea Sulliotti, G.R., 1924)
• Trona stercoraria minima (Linnaeus, C., 1758)
• Trona stercoraria var. rattus (Lamarck, 1810): accepted as Trona stercoraria (Linnaeus, 1758)
• Trona stercoraria var. tumulosa (Meuschen, 1778) accepted as Trona stercoraria (Linnaeus, 1758)
• Trona stercoraria cameroonica Lorenz 2017

References

• Meuschen, F.C. (1778). Mvsevm Gronovianvm. Sive Index Rervm Natvralivm tam Mammalivm Amphibiorvm Piscivm Insectorvm Conchyliorvm Zoophytorvm Plantarvm et Mineralivm exqvisitissimorvm qvam Arte factarvm nonnvllarvm. Inter qvae eminet Herbarivs siccvs Plantarvm a Tovrnefortio Claitonio Linnaeo aliisqve Botanicis collectarvm. Qvae omnia mvlta Cvra et magnis Svmptibvs sibi comparavit Vir amplissimvs & celeberrimvs Lavr. Theod. Gronovivs J.V.D. Civitatis Lvgdvno Batavae Senator et Scabinvs Societatis Regiae Londinensis Basilaeensis et Hollandiae qvae Harlemi est aliorvmque Socivs &c. &c. Th. Haak & Socios J. Meerburg, Lvgdvni Batavorvm, vi + 251
• Bernard, P.A. (Ed.) (1984). Coquillages du Gabon [Shells of Gabon]. Pierre A. Bernard: Libreville, Gabon. 140, 75 plates pp.
• Lorenz & Hubert (2000). A guide to worldwide cowries. ConchBooks 1-584 page(s): 52
• Burgess, C.M. (1985) Cowries of the World. Gordon verhoef, Seacomber Publications, South Africa, Cape Town. XIV + 289 pp. page(s): 111

References

1. {{WRMS species. 225254. ''Trona stercoraria'' (Linnaeus, 1758). 6 January 2019
2. "''Trona stercoraria stercoraria''".
3. "''Trona stercoraria minima''".
4. "''Trona stercoraria rattus''".