Source: http://worldwideconchology.com/fam/Cassidae.shtml
Timestamp: 2019-04-20 14:23:40+00:00

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The Family CASSIDAE are a relatively small group of marine mollusks, but include some of the largest molluscan species. Cassis cornuta, the type species of the genus, is probably the largest -- a specimen measuring over 16 inches in length has been recorded. The Family consists of two subfamilies and eight genera according to the most current literature (see below). Commonly known as Helmet Shells, or Bonnets, the Cassidae inhabit tropical and temperate oceans from intertidal to subtidal depths; a few as deep as 500 fathoms of water. Many species surface as a bi-product of the fishing industry in trawling nets, and by dredging. Many of the largest species can also be collected by divers and snorkelers. The large species of Cassis are a food source in certain parts of the world. The Indo-Pacific Cypraecassis rufa is commonly used for carving cameos. Other large species have also been used for this ancient art, but the thick shell of Cypraecassis rufa is preferred by artisans for executing the bas-relief carving.
Ecology of Cassis: Cassis cornuta has been observed gathering in large numbers on sandy patches in about 60 feet of water off Maui, Hawaii (pers.comm. P.Fiene-Severns). As many as 46 were mating and laying eggs. This gregarious behavior has also been reported with Cassis madagascariensis spinella off the Florida Keys in about 30 feet of water. These large Cassis species are typically buried in sand with only a small portion of the dorsum, or dorsum spine exposed above the substrate. The dorsum is often encrusted, or covered with thick algae growth, which makes it difficult to distinguish the shell from other bottom debris.
LITERATURE: The Cassidae have been rather well illustrated in popular shell books, yet little attention has been paid to the family. The release of Recent Cassidae by Kurt Kreipl (Verlag Christa Hemmen, Wiesbaden, Germany, 1997) has once again re-focused collectors' attentions on this often overlooked family. This excellent book includes color photographs of the known living species of Cassidae with a basic synopsis on each. Recent Cassidae diverges taxanomically from the long-standing classic monograph on the Cassidae, The Helmet Shells Of The World (Cassidae) by R. Tucker Abbott (Indo-Pacific Mollusca, Vol. 2, No. 9, 1968). Abbott's monograph still stands as one of the most important scientific works on the Cassidae. The in depth write-ups on each species, including fossils, gives collectors a solid picture of the Family. For the serious Cassis-collector both titles are essential reading for a better understanding of the family.
e.g., use Cassis instead of Cassis shell.
Cassis Scopoli, 1777. Type species : Cassis cornuta (Linnaeus, 1758); Vaught, 1989: 36 [Cassinae]; Pacaud & Le Renard, 1995: 164 [Cassidae]; Cassida Brunnich, 1772 (non Linnaeus, 1758); Cassidea Bruguière, 1789; Cassis Röding, 1798; Cassinia Rafinesque, 1815 (error); Goniogalea Mörch, 1857; Fimbriola Megerle in Scudder, 1882 (nom. nud.); Cassisoma Rovereto, 1899; Pro Cassis Klein, 1753 (non-binom.); Galeodocassis Sacco, 1890 (fossil); Subgenus : HYPOCASSIS Iredale, 1927; Nannocassis Iredale, 1927; Cassis (Hypocassis); Vaught, 1989: 36 [Cassinae]; Subgenus : MORIONELLA Dall, 1909; Cassis (Morionella); Pacaud & Le Renard, 1995: 164 [Cassidae]. Ref.: Millard, V. 1997. Classification of the Mollusca :A classification of worldwide Mollusca. pp.119-120. Cassis cornuta (Linné, 1758) - Philippines, 205mm - collected back in the 1970's. It was found crawling on sand in 3 meters of water. Ref.: Abbott, R.T., 1968. Indo-Pacific Mollusca, Vol.2, No.9, p.47; Kreipl, K., 1997. Recent Cassidae. p.13, pl.1. Cassis madagascariensis (Lamarck, 1822) form: spinella Clench 1944 - Florida Keys, 250mm - collected scuba diving in 30 feet of water, on sand. Ref.: Abbott, R.T., 1974. American Seashells, Second Ed., p.161, No.1744; Kreipl, K., 1997. Recent Cassidae. p.15, pl.2.
Cassis madagascariensis (Lamarck, 1822) form: spinella Clench 1944 - Florida Keys - specimens fresh out of the water, taken from about 30 feet off water off central Florida Keys. This picture illustrates the organic growth and encrustations that are often found on living Helmet shells. Ref.: Cassis (Hypocassis) nana Tenison-Woods, 1879 - Queensland, Australia, 50mm - at a maximum size of about 65mm Cassis nana is the smallest species of the genus. It is main found from trawl nets set in relatively deep water from Townsville, Queensland south to central New South Wales. Ref.: Abbott, R.T. 1968. Indo-Pacific Mollusca - Cassidae. p.65, pl. 4, figs. 5-6, pl. 39.
Galeodea Link, 1807. Type species : Galeodea echinophora (Linnaeus, 1758); Vaught, 1989: 36 [Cassinae]; Pacaud & Le Renard, 1995: 164 [ Cassidae]; Le Renard, 1996: 50; Morio Montfort, 1810 (non Latreille, 1810); Cassidaria Lamarck, 1812; Echinora Schumacher, 1817; Galeoda Schaufuss, 1869; Morio Montfort, 1810 (non Latreille, 1810); Echinophora Latreille, 1825; Doliopsis Conrad, 1865 (non Voigt, 1952); Galeodaria Conrad, 1865; Subgenus: GALEOOCORYS Kuroda & Habe, 1957; Galeodea (Galeoocorys); Vaught, 1989: 36 [Cassinae]; Subgenus: MAMBRINIA Gardner, 1939; Galeodea (Mambrinia); Pacaud & Le Renard, 1995: 164 [Cassidae]. Ref.: Millard, V. 1997. Classification of the Mollusca :A classification of worldwide Mollusca. pp.119-120. Galeodea echinophora (Linné 1758) - Mediterranean, 60-70mm. Ref.: Kreipl, K. 1997. Recent Cassidae. p.24, pl. 8, figs. 15-15c. Galeodea (G.) keyteri Kilburn, 1975 - Madagascar, 73mm - trawled in deep water. Ref.: Kreipl, K. 1997. Recent Cassidae. p.26, pl. 9, fig. 19.
Sconsia Gray, 1847; Vaught, 1989: 36 [Cassinae].
Ref.: Millard, V. 1997. Classification of the Mollusca :A classification of worldwide Mollusca. pp.119-120. Sconsia_lindae Petuch, 1987 - Colombia, 66mm - limited range in the southwestern Caribbean, mainly trawled off the coast of Colombia. Ref.: Sconsia_lindae Petuch, 1987 - Colombia, 58mm - an unusual specimen with a golden color form and lacking markings.
Sconsia striata (Lamarck, 1816) - Dry Tortugas, Florida Keys, 58mm - dredged in 100-150 feet of water by shrimp boat in 1970's. Ref.: Abbott, R.T., 1974. American Seashells, Second Ed., p.160, No.1730; Kreipl, K., 1997. Recent Cassidae. p.31, pl.10. Sconsia striata (Lamarck, 1816) - Colombia, 45mm - trawled off Cabo la Vela, Guajira Peninsula. Though a smaller specimen, it cannot be referred to as a dwarf specimen since the thickened lip will become a varice (rib) as the mollusk continues to add a whorl to its shell. A synonym is S. grayi Ref.: Clench, W.J, Abbott, R.T. 1943. The Genera Cypraecassia, Morum, Sconsia and Dalium in the Western Atlantic. Johnsonia, No. 9, p. 6, pl. 4.
Herculea Hanley in H. & A. Adams, 1858; Vaught, 1989: 36 [Cassinae]. Ref.: Millard, V. 1997. Classification of the Mollusca :A classification of worldwide Mollusca. pp.119-120.
Ref.: Millard, V. 1997. Classification of the Mollusca :A classification of worldwide Mollusca. pp.119-120.
Ref.: Millard, V. 1997. Classification of the Mollusca :A classification of worldwide Mollusca. pp.120.
Phalium fimbria (Gmelin, 1791) - Andaman Sea, 120.5mm - An exceptionally large specimen trawled off Thailand. Rarely is this species found this size, but a specimen of 128mm has been recorded. Ref.: Kreipl, K., 1997. Recent Cassidae. p.36, pl.12. Phalium muangmani Massilia & Musetti, 1995 - Thailand, 70mm. Ref.: Kreipl, K., 1997. Recent Cassidae. p.38, pl.13, fig. 36-36a.
Casmaria H. & A. Adams, 1853. Type species : Casmaria erinaceus (Linnaeus, 1758) Casmeria Jousseaume, 1888. Ref.: Millard, V. 1997. Classification of the Mollusca: A classification of worldwide Mollusca. pp.120.
Echinophoria (Bathygalea); Vaught, 1989: 36. Ref.: Millard, V. 1997. Classification of the Mollusca: A classification of worldwide Mollusca. pp.120.
Faurotis Jousseaume, 1888; Bezoardica Dall, 1909 (non Schumacher, 1817); Tylocassis Woodring, 1928; Xenophalium Iredale, 1927; Xenogalea Iredale, 1927; Kahua Marwick, 1928; Subgenus: ANTEPHALIUM Iredale, 1927. Ref.: Millard, V. 1997. Classification of the Mollusca: A classification of worldwide Mollusca. pp.120. Phalium bisulcata (Schubert & Wagner, 1829) - Indonesia, 34-44mm. Ref.: Kreipl, K., 1997. Recent Cassidae. p.48-49, pl.17, figs. 54-54g. Phalium bisulcata (Schubert & Wagner, 1829) [form: japonica Reeve, 1848] Philippines, 56mm -- an extremely variable species. This specimen is quite dark for the species. Ref.: Kreipl, K., 1997. Recent Cassidae. p.48-49, pl.17, figs. 54-54g.
Semicassis granulata peristephes (Pilsbry & McGinty, 1939) - Brazil, 45-48mm - a form with strong spiral cords crossed by axial grooves and often with shoulder nodules. Ref.: Kreipl, K., 1997. Recent Cassidae. p.53, pl.19, fig. 62c. Semicassis labiata iredalei (Bayer, 1935) [= zeylanicum] - South Africa, 38-45mm - the name iredalei is a form that is typically smaller than average in size. Ref.: Kreipl, K., 1997. Recent Cassidae. p.58, pl.20, fig. 68b. Semicassis (S.) microstoma (von Martens, 1903) - Somalia, 59-67mm. Ref.: Kreipl, K., 1997. Recent Cassidae. p.59, pl.21.
Semicassis (S.) umbilicata (Pease, 1861) - Hawaii, 67-73mm - taken from deep water trap set off northwest Oahu. Ref.: Kreipl, K. 1997. Recent Cassidae. p.63, pl. 23, figs. 76-76a. Semicassis (Semicassis) whitworthi (Abbott, 1968) - Western Australia, 71mm - A deep water species, rarely found in living condition in trawl nets and lobster pots. The unmistakable beaded cords cannot be confused with any other molluscan species. Ref.: Abbott, R.T., 1968. The helmet shells of the world (Cassidae) Pt.1. Indo-Pacific Mollusca. 2(9), p.179-181.; Wilson, B., 1993. Australian Marine Shells. Vol. 1, p.234. Odyssey Publishing, Australia; Kreipl, K., 1997. Recent Cassidae. p.64, pl.23, fig. 78-78a.

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