Montacuta percompressa
| Montacuta percompressa | ||||||||||||
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| Scientific name | ||||||||||||
| Montacuta percompressa | ||||||||||||
| Dall , 1899 |
Montacuta percompressa is a type of mussel from the lentil mussel family(Montacutidae). The species lives commensally with the sea cucumber Leptosynapta tenuis , either attached to the spines with linen or creeping freely on the host. The males are dwarf males that live parasitically in the mantle of the females.
features
The same-lobed, narrow (compressed) housing of the female is oblong-egg-shaped and is up to five millimeters long. The height is about 80% of the length. The (dwarf) males grow up to 500 µm, they no longer have a housing. The shells (of the females) are unequal, the vertebra sits behind the middle of the shell length. The front edge is slightly extended and rounded, the rear edge of the case is slightly more rounded. The ventral margin is slightly curved. The inner edge of the case is smooth. In the right flap, the lock consists of a cardinal tooth and a longitudinal pit into which the lateral tooth of the left flap “fits”. A lateral tooth sits in the left valve. The surface line is not indented. The Prodissoconch measures 120 to 200 µm in length, 85 to 125 µm in height and 40 to 100 µm in thickness. The surface has irregular concentric stripes. The shell is thin.
Similar species
The housing of the elongated lentil shell ( Tellimya ferruginosa ) is significantly larger, more elongated, slimmer and more expanded than Montacuta percompressa .
Way of life
The species is segregated. The females live with byssus attached to the spines of the sea cucumber Leptosynapta tenuis , or crawl around freely on the host. The males are reduced to dwarf males, living parasitically in the coat of the females. They no longer have a housing and are basically reduced to egg-shaped gonadal tissue. The fertilization of the eggs takes place in the mantle cavity of the female.
Fertilized eggs are “incubated” in a brood pouch, which is formed as a protuberance in the back of the mantle. A brood comprises between 450 and 16,900 larvae, depending on the size of the eggs. After five to seven days they are released into the open water as Veliger larvae. They then live planktotroph for a period of time before they switch to soil life and metamorphosis after 17 to 31 days . The Pediveliger are at this time to 385 microns long already 350 and have already developed a foot and gills. The castle is initially not differentiated; the ligament only appears at a size of 310 µm. A second “brood” can be formed after around 14 to 19 days.
Taxonomy
The taxon was established in 1899 by William Healey Dall . According to MolluscaBase, the taxon belongs to the genus Montacuta Turton, 1822.
supporting documents
literature
- Paul Chanley, Matoira Chanley: Larval development of the commensal clam, Montacuta percompressa Dall. Journal of Molluscan Studies, 39 (1): 59-67, 1970 PDF
- Gennady M. Kamenev: Little-known arctic species Montacuta spitzbergensis (Bivalvia: Montacutidae) from the north-western Pacific with notes on Montacuta substriata and Tellimya ferruginosa. Journal of the Marine Biological Association of the United Kingdom, 88 (2): 347-356, 2008 doi : 10.1017 / S002531540800056
Individual evidence
- ^ William Healey Dall: Synopsis of the recent and Tertiary Leptonacea of North America and the West Indies. Proceedings of the United States national Museum, 21: 873–897, 1899 Online at www.biodiversitylibrary.org (p. 894)
- ^ MolluscaBase: Montacuta percompressa Dall, 1899