Drupa ricinus
| Drupa ricinus | ||||||||||||
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Enclosure of Drupa ricinus , Mindanao, Philippines |
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| Scientific name | ||||||||||||
| Drupa ricinus | ||||||||||||
| ( Linnaeus , 1758) |
Drupa ricinus is the name of a snail from the family of spiny snails thatis commonin the Indo-Pacific . It is the only known predatory snail species that, in addition to decapods and other mobile prey, occasionally also prey on fish without the use of poison.
features
The compact shell of Drupa ricinus , which in adult snails reaches a length of about 2.8 cm, has a low thread and a narrow, long shell mouth. The outer lip of the case mouth is thick and has two serrated teeth. The spindle has two or three strong folds and small granules at the base. The snail shell is sculptured with 5 spiral rows of pointed or blunt spines. The surface of the shell is cream or pale yellow, the spike tips dark brown or black, the inside of the case mouth is white with an orange line on the edge.
distribution and habitat
Drupa ricinus is widespread in the Indian Ocean on the East African and South African coasts of KwaZulu-Natal and in the western Pacific Ocean , but also in the Red Sea , where it can be found on rocky subsoil in the intertidal zone.
Life cycle
Like other spiny snails, Drupa ricinus is segregated with internal fertilization. From the egg capsules deposited after mating, similar to Drupa morum, distinctly teleplane, large Veliger larvae hatch, which, thanks to their long-lived stage as zooplankton, contribute to the widespread distribution of the species in the Indo-Pacific and to the colonization of isolated archipelagos in the Eastern Pacific.
nutrition
The prey spectrum of Drupa ricinus is considered the widest among the whelks: So, in addition to crabs - decapods , amphipods , isopods and barnacles - polychaete families Nereidae and Eunicidae , sipuncula , snails family Vermetidae and Chitons and occasionally fish caught and eaten. The subspecies Drupa ricinus lischkei (Hidalgo, 1904), better known under the synonym Drupa ricinus hadari Emerson & Cernohorsky, 1973, living in the Red Sea , is reported to catch small fish and decapods by opening the entrances to small caves or empty snail shells in which the animals seek refuge, locked with their bodies, then reached the trapped victim with their proboscis and rasped with the sharp teeth of their radula . In 1982 by John D. Taylor published studies of the intestinal contents of more than 100 of these snails, showed that 57% of prey crabs (decapods, mantis shrimp and amphipods), 17% Nereidae, 4% other polychaete (usually Eunicidae), 11% Vermetidae and 4% were snails. Eight snails (7%) contained scales and bones from fish that were assigned to the Gobiidae family . Drupa ricinus is the only known type of snail, along with several cone snail species, that prey on fish, but without poison.
literature
- Richard Kilburn, Elizabeth Rippey: Sea Shells of Southern Africa. Macmillan South Africa, Johannesburg 1982. p. 87.
- DG Steyn, Markus Lussi: Marine Shells of South Africa: An Illustrated Collector's Guide to Beached Shells. Ekogilde Publishers, Hartebeespoort 1998. p. 43.
- John D. Taylor (1975): The food of coral-reef Drupa (Gastropoda). Zoological Journal of the Linnean Society 78, pp. 299-316.
- John D. Taylor (1978): Habitats and diet of predatory gastropods at Addu Atoll, Maldives. Journal of Experimental Marine Biology and Ecology 31, pp. 83-103.
- John D. Taylor (1982): Fish in the diet of Drupa ricinus hadari. Journal of Conchology 31 (2), p. 134.
- John D. Taylor (1983): The food of coral-reef Drupa (Gastropoda). Zoological Journal 78 (4). Pp. 299-316.
- Jane Bartlett Taylor (1975): Planktonic prosobranch veligers of Kaneohe Bay. Ph.D. thesis, University of Hawaii.
- Martine Claremont, David G. Reid, Suzanne T. Williams (2012): Speciation and dietary specialization in Drupa, a genus of predatory marine snails (Gastropoda: Muricidae). Zoologica Scripta 41 (2), pp. 137-149.
Web links
Individual evidence
- ↑ Jane Bartlett Taylor (1975): Planktonic prosobranch veligers of Kaneohe Bay. Ph.D. Thesis, University of Hawaii, Honolulu. 593 pages.