Nuculida
Nuculida | ||||||||||
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Systematics | ||||||||||
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Scientific name | ||||||||||
Nuculida | ||||||||||
Dall , 1889 |
The Nuculida are an order of the mussels (Bivalvia), which was formerly also called Palaeotaxodonta . The order is placed in the infra-class Protobranchia within the class of mussels. The oldest representatives are known with a certain uncertainty from the Lower Cambrian , certainly from the Ordovician .
Characteristics
The representatives of the order have housings with the same flaps , the rear end of which can also be more or less elongated. The bowl is aragonitic with homogeneous or mother-of-pearl prismatic structures. The lock is taxodont , a few forms also have an actinodontic lock. The ligament can be external or internal on a ligament support. The sphincter muscles are uniform (isomyar). The gills belong to the so-called protobranch type. The rather long mouth probes lie around the mouth opening.
Way of life
The representatives of the order Nuculida live exclusively marine, but occur from the subtidal to abyssal depths. They live mostly buried in the soft sediment as detritus eaters.
Systematics
The order contains the following superfamilies:
- Superfamily Nuculoidea Gray, 1824
- Nut clams family (Nuculidae Gray, 1824)
- Subfamily Nuculinae Gray, 1824
- Subfamily Nuculominae Maxwell, 1988
- Subfamily Palaeonuculinae Carter, 2001
- Family Nucularcidae Pojeta & Stott, 2007
- Family Palaeoconchidae SA Miller, 1889
- Family Praenuculidae McAlester, 1960
- Nut clams family (Nuculidae Gray, 1824)
- Superfamily Sareptoidea Stoliczka, 1870
- Family Sareptidae Stoliczka, 1870
- Subfamily Sareptinae Stoliczka, 1870
- Subfamily Pristiglominae Sanders & Allen, 1973
- Family Sareptidae Stoliczka, 1870
supporting documents
- Michael Amler, Rudolf Fischer & Nicole Rogalla: Mussels . Haeckel library, volume 5. Enke Verlag, Stuttgart 2000 ISBN 3-13-118391-8 .
- Rüdiger Bieler & Paula M. Mikkelsen: Bivalvia - a look at the branches . Zoological Journal of the Linnean Society, 148: 223-235, London 2006.