Scaphula

from Wikipedia, the free encyclopedia
Scaphula
Scaphula minuta (from Gosh, 1922: Text-fig. 6 [1])

Scaphula minuta (from Gosh, 1922: text fig. 6)

Systematics
Subclass : Autolamellibranchiata
Subclass : Pteriomorphia
Order : Arcida
Superfamily : Arcoidea
Family : Ark clams (Arcidae)
Genre : Scaphula
Scientific name
Scaphula
Benson , 1834

Scaphula is a shell - genus from the family of ark shells (Arcidae). The representatives of the genus Scapharca live in fresh and brackish water ; the distribution area extends over large parts of Southeast Asia.

features

The mostly equally-folded, clearly elongated housings are small to very small (4.5 to approx. 13 millimeters long) and comparatively bulky (L: 4.5 mm, H: 2 mm, D: 2 mm for Scaphula minuta or L: 10 mm, H: 3.5 mm, D: 6.5 mm with scaphula deltae ). They are rounded-rhomboidal in outline and can be twisted somewhat in the longitudinal axis. The vertebrae sit well in front of the midline (about a quarter from the front end). A distinct keel (or double keel) extends from the vertebra to the lower, rear end. It clearly separates the rear case field from the rest of the case. The ligament is elongated and extends in front of and / or behind the vertebrae. In the lock, the teeth sit in two groups, which are separated from each other by a toothless, central area. The posterior teeth are very crooked. The anterior sphincter is significantly smaller than the posterior sphincter.

The ornamentation in the central and front housing field consists of more or less coarse growth strips parallel to the edge, which intersect with weaker radial lines. The rear housing field, separated from the (double) keel, has stronger radial lines or weaker keelings that intersect with weak growth strips.

Geographical distribution and habitat

Species of the genus Scaphula have so far been recorded from India , Bangladesh , Myanmar , Thailand and Vietnam .

They live in the fresh water of rivers under stones or on water plants, other mollusks (snails and mussels), attached with byssus threads. Most species are also found in the brackish water of the river deltas.

Taxonomy

The genus Scaphula was established in 1834 by William Henry Benson . In his two works from 1834, however, he did not mention any species. Type species through secondary monotype is the species Scaphula celox , which Benson then established in 1836. The name Scaphula was later given to a species of snail and an insect species.

Scaphula bensoni H. Adams, 1872 is a younger synonym of Scaphula pinna Benson, 1856, and Scaphula lanceolata Hutton, 1885 is now part of the genus Poroleda Hutton, 1893. Scaphula Benson, 1834 is the type genus of the Scaphulinae subfamily Scarlato & Starobogatov, 1979. However, the subfamily structure of the ark mussels is only used by a few authors. Arca (Scaphula) convergidens Gerhardt, 1897 from the Chalk of South America is, according to Philipp Reinhart, a species of the genus Cucullaea .

supporting documents

literature

  • Markus Huber: Compendium of Bivalves. Volume 1. 901 S., ConchBooks, Hackenheim 2010 (p. 575).
  • Henk K. Mienis, Oz Rittner: Brief review of the fresh water ark shells belonging to the genus Scaphula Benson, 1834 (Fam. Arcidae). Triton, 34: 16–20, 2016 PDF (ResearchGate)
  • Norman D. Newell: Scaphula Benson, 1834. In: Raymond Cecil Moore (Ed.): Treatise on invertebrate paleontology. Mollusca, 6, Bivalvia 1. XXXVIII, S.N256, New York, 1969.

Individual evidence

  1. ↑ a b Ekendranath Gosh: On the anatomy of Scaphula, Benson, with a description of a new species. Proceedings of the Zoological Society of London, 1922: 1139-1144, London 1922. www.biodiversitylibrary.org
  2. ^ A b William Henry Benson: A collection of land and freshwater shells found in the Gangetic provinces of India. Proceedings of the Zoological Society of London, (2) 20: 89-91, London 1834a. { http://www.biodiversitylibrary.org/item/96158#page/103/mode/1up Online at www.biodiversitylibrary.org] (p. 91)
  3. ^ William Henry Benson: Conchological Notices; chiefly relating to the Land- and Fresh-water Shells of the Gangetic Provinces of Hindoostan. The Zoological Journal, 5: 458-466, London 1834b Online at www.biodiversitylibrary.org (p. 464).
  4. ↑ a b William Henry Benson. Descriptive catalog of a collection of land and fresh-water shells, chiefly contained in the Museum of the Asiatic Society. Part 2, Fluviatile shells. Journal of the Asiatic Society of Bengal, 5 (59): 741-750, Calcutta 1836 Online at www.biodiversitylibrary.org (p. 750).
  5. ↑ Nomenclator Zoologicus: Scaphula
  6. ↑ a b c MolluscaBase: Scaphula Benson, 1834
  7. ^ A b William Henry Benson: Amended description of the genus Scaphula, Benson, a freshwater form of the Arcacea; with characters of a new species from Tenasserim. Annals and Magazine of Natural History, (2) 17: 127-129, London 1856 Online at www.biodiversitylibrary.org (p. 127).
  8. ^ William Thomas Blanford: Contributions to Indian Malacology, No. VIII. List of estuary shells collected in the delta of the Irawady, in Pegu, with descriptions of the new species. Journal of the Asiatic Society of Bengal, 36 (2): 51-72, 1867 Online at www.biodiversitylibrary.org (p. 71) plate 3 and plate 14 .
  9. ↑ K. Janaki Ram, Y. Radhakrishna: The distribution of freshwater mollusca in Guntur District (India) with a description of Scaphula nagarjunai sp. n. (Arcidae). Hydrobiologia, 119 (1): 49-55, 1984 doi : 10.1007 / BF00016863
  10. ^ K. Gerhardt: Contribution to the knowledge of the chalk formation in Venezuela and Peru. New Yearbook for Mineralogy, Geology and Paleontology, Supplement Volume 11: 65-117, Stuttgart 1897. Online at www.archive.org (p. 98)
  11. ^ Philip W. Reinhart: Classification of the Pelecypod Family Arcidae. Bulletin du Musée royal d'Histoire naturelle de Belgique, 11 (13): 1-68, Brussels 1935 PDF

Web links

Commons : Scaphula  - collection of images, videos and audio files