Ivory cone
| Ivory cone | ||||||||||||
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Housing of Conus eburneus |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Conus eburneus | ||||||||||||
| Hwass in Bruguière , 1792 |
The ivory cone or ivory-cone shell ( Conus eburneus ) is a screw from the family of the cone snails (genus Conus ), which in Indopazifik is widespread and mainly on Vielborstern , but also of small fish feeds.
features
Conus eburneus carries a medium-sized to moderately large, moderately firm to heavy snail shell , which in adult snails reaches 3.5 to 8 cm in length. The circumference of the body is conical to broad or bulbous conical, occasionally conical cylindrical, the outline at the shoulder convex to onion-shaped and straight towards the base, the base cut off. The shoulder is angled to rounded. The thread is low, its outline is concave to straight or S-shaped. The Protoconch is multi-threaded and measures a maximum of 0.7 mm. The seam ramps of the Teleoconch are almost flat with 2 narrow but deeply incised spiral grooves in the first whorls and 2 to 5 grooves in the later whorls. Ribs in between and a rib on the shoulder are often emphasized, sometimes only weakly on the last passages. The area around the body is provided in a quarter to half at the base with weak, spiraling fine ribs and cords.
The basic color of the housing is white. The body is covered in alternating intervals with spiral rows of reddish-brown to black, square spots, rectangular bars or comma-shaped stripes. Under the spiral rows there can be 3 yellow, orange or dark yellow bands on the shoulder and on either side of the center. The whorls of the Protoconch are white. The seam ramps of the Teleoconch have reddish-brown to blackish spots, axial stripes or spots. The density of the pattern on the thread corresponds to that of the body circumference. The inside of the case mouth is white.
The thin, translucent, and smooth periostracum in almost adults is yellowish-orange and becomes less translucent and olive-brown in fully grown animals.
The top of the foot is ivory, with occasional beige on the sides and back. The edge area of the middle and rear sections has radial gray, black and various shades of brown. The front section is often covered with 2 to 3 triangular, granular, black spots radiating from the center and with 2 gray to black markings next to the front corners. The sole of the foot is ivory to pink-beige with white and dark yellow spots or yellow-brown with a dark yellow leading edge. The rostrum is pale pink or yellow-brown, the antennae white, sometimes distally and dorsally dark yellow. The sipho is distally white with a pink, yellow or dark yellow edge, in the middle dark yellow or white with 1 or 2 irregular black rings that merge lateroventrally into gray, proximally light brown with dark brown and black spots on the dorsal side.
The radula teeth, which are connected to a poison gland , have a barb on the tip and a long cutting edge on the opposite side. From the end of the barb to the end of the cutting edge they are sawn over a short distance. A spur sits at the base.
distribution and habitat
Conus eburneus is distributed in the Indo-Pacific from the coast of East Africa via Madagascar and Chagos to Australia , Polynesia and the Ryūkyū Islands . It lives in the intertidal zone and down to a depth of about 65 m, but mostly at depths of 1 m to 25 m, mainly on sand, but also between vegetation on sandy or muddy subsoil.
Development cycle
Like all cone snails, Conus eburneus is sexually separate and the male mates with the female with his penis . The female lays egg capsules with numerous eggs that are about 150 µm in diameter. From this it is concluded that the Veliger larvae swim freely for at least 28 days before they sink and metamorphose into crawling snails .
nutrition
The prey of Conus eburneus consists mainly of Vielborstern verschiedenster both sedentary and erranter families, but he also eats small fish , which he shares with his Radulazähnen stands and using the poison out of his venom gland immobilized. Annular worms that are eaten come from the families Eunicidae and Capitellidae , but also Nereididae . The poison is fatal to annelids, mollusks and small fish, but is less toxic to small mammals.
literature
- George Washington Tryon: Manual of Conchology, structural and systematic, with illustrations of the species , vol. VI; Academy of Natural Sciences, Philadelphia 1884. C [onus] eburneus Hwass., P. 11.
- Jerry G. Walls: Cone Shells: A Synopsis of the Living Conidae TFH Publications, Neptune (New Jersey) 1979. p. 419.
- Dieter Röckel, Werner Korn, Alan J. Kohn: Manual of the Living Conidae Vol. 1: Indo-Pacific Region . Verlag Christa Hemmen, Wiesbaden 1995. The texts on the individual cone snail species of the Indo-Pacific are published on The Conus Biodiversity website with the permission of the authors (see web links).
Web links
- The Conus Biodiversity website: Conus eburneus Hwass in Bruguière, 1792
- Underwater Kwajalein: Conus eburneus Hwass in Bruguière, 1792
Individual evidence
- ↑ Alan J. Kohn, James W. Nybakken (1975): Ecology of Conus on eastern Indian Ocean fringing reefs: diversity of species and resource utilization. Marine Biology 29, pp. 211-234.
- ↑ Baldomero M. Olivera, Jon Seger, Martin P. Horvath, Alexander E. Fedosov: Prey-Capture Strategies of Fish-Hunting Cone Snails: Behavior, Neurobiology and Evolution. In: Brain, behavior and evolution. Volume 86, number 1, September 2015, pp. 58-74, doi : 10.1159 / 000438449 , PMID 26397110 , PMC 4621268 (free full text) (review).
- ^ Robert Endean, Clare Rudkin (1963): Studies of the venoms of some Conidae. Toxicon 1, pp. 49-64.