Kurtiella pedroana
| Kurtiella pedroana | ||||||||||||
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Kurtiella pedroana |
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| Scientific name | ||||||||||||
| Kurtiella pedroana | ||||||||||||
| ( Dall , 1899) |
Kurtiella pedroana is a type of mussel from the lentil mussel family(Montacutidae). The species lives commensally in the gill cavity of the decapod Blepharipoda occidentalis Randall, 1840.
features
The often somewhat unevenly folded , moderately inflated housing is egg-shaped and somewhat elongated at the front end. The front edge is strong, the rear edge less curved. The ventral margin is almost straight. The comparatively large cases are up to 9.2 mm long. The height reaches about 80% of the length. The opisthogyrate vertebrae sit somewhat behind the middle of the length of the case. The housing is often twisted slightly to one side or the other at the front end. As a result, a valve is a little less inflated. The lock has a strongly developed resilium under the vertebra, which sits in a deep resilifer. There is no external ligament . The right valve has a front, long and a rear, shorter lamellar tooth. The two lamellae diverge in a V-shape on both sides of the resilium. The dorsal edge of the housing and the two lamellar teeth each enclose a longitudinal pit between them. The left flap has two thin lamellae, roughly parallel to the dorsal edge of the housing, which fit into the two longitudinal pits of the right flap.
The shells are comparatively thin. The surface is chalky-white with coarse, irregular, concentric growth lines. The periostracum is thick, yellow to brown-black in color. The Prodissoconch measures 37 μm in length.
The mantle edges are fused at the rear edge , from the "heel" of the foot to the vertebra. An area in the rear part of the ventral margin for the outflowing water is excluded from the adhesion. The free ends of the mantle are somewhat thickened and covered with short, blunt protuberances (papillae). The jacket edges do not overlap on the outer housing surface. The muscle impressions are clearly pronounced. The anterior sphincter is elongated and the posterior sphincter is rounded. The two foot retractor muscles sit directly next to the sphincter muscles. The surface line is complete. The muscular foot is spade-shaped with a more or less distinct sole. The ventral longitudinal pit extends almost the entire length of the foot. It is bordered by glandular tissue; a mucous gland sits on the "heel".
The gills consist only of the inner half-leaf. The slats are only connected to one another by a few slat bridges. The gill space serves as a breeding chamber in which the eggs or the developing larvae are retained. The labial palps are small. The throat (esophagus) is moderately short and widens evenly towards the simple stomach. Three passages of the digestive glands open into the large central chamber. The sac of the crystal sac is long, points almost exactly backwards and runs parallel to the rectum. The midgut is separate from the sac of the crystal stem and runs directly without a loop. The gonads can contain eggs and sperm, so the animals are real simultaneous hermaphrodites , at least at some point in their life cycle.
Geographical distribution, habitat and way of life
Kurtiella pedroana lives in the gill cavity of the decapod Blepharipoda occidentalis Randall, 1840, attached to the gills with byssus threads . There the mussel filters food from the water flowing by. So it does not feed on its host , but rather, as a commensal, is supplied with sufficient nutrition by its gill activity. The advantage for the mussel is that it is relatively well protected in the gills and that the water flow through the gills of the host receives more food particles than in the free ocean current. Still, this way of life can harm the host. Although the oxygen uptake of the cancer by the mussels that have attached to the gills is not or not measurably impaired, necrosis of the gill tissue often occurs at the attachment points . The existence of wild specimens suggests, however, that the mussel is viable even without the interspecific interrelation with the cancer Blepharipoda occidentalis .
Kurtiella pedroana has a well-developed byssus apparatus which is able to produce new byssus threads almost at any time and quickly when it is necessary (e.g. when the host cleans his gills and tears the commensal loose). The often somewhat unevenly hinged housing is not correlated with the position within the gill cavity of the cancer.
How Kurtiella pedroana reacts to the periodic molting of its host is not known. It would be conceivable that Kurtiella pedroana completes a life cycle between two moults or that the mussel detaches from the moulting shirt and attaches itself again to the same host (or to another host) or also goes over to free life. Kurtiella pedroana has also been found living free on occasion.
Kurtiella pedroana is host-specific and has not yet been detected in the other three species of the genus Blepharipoda . Also at the two closely related species of Lophomastix comes Kurti Ella pedroana not available.
The eggs are internally fertilized and initially retained in the mantle cavity. There the larvae develop into planktotrophic Veliger larvae with a D-shaped Prodissoconch with a housing length of 157 to 186 μm (mean: 175 μm).
Taxonomy
The taxon was established in 1899 by William Healey Dall as Mysella pedroana . The MolluscaBase places the species in the genus Kurtiella Gofas & Salas, 2008.
supporting documents
literature
- Christopher B. Boyko, Paula M. Mikkelsen: Anatomy and Biology of Mysella pedroana (Mollusca: Bivalvia: Galeommatoidea), and its Commensal Relationship with Blepharipoda occidentalis (Crustacea: Anomura: Albuneidae). Zoologischer Anzeiger, 241: 149-160, 2002 doi : 10.1078 / S0044-5231 (04) 70070-4
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. 893)
- ↑ MolluscaBase: Kurtiella pedroana (Dall, 1899)