Enigmonia is a genus of saltwater clams, a marinebivalvemollusc in the familyAnomiidae, the jingle shells. Enigmonia aenigmatica, the mangrove jingle shell clam, is the only species in this monotypic genus. It is found living on mangroves in the Indo-Pacific Ocean.
The mangrove jingle shell clam can grow to a length of about 3 centimetres (1.2 in). The shell is thin and delicate. Although this species is a bivalve, only the upper valve is normally visible, and that valve is elongated or oval with a low dome, and thus the general appearance which is like that of a limpet. The umbone of the shell is off centre, near the dorsal margin of the shell. A few fine ridges radiate from the umbone and there is a sculpting of concentric growth rings. The lower valve has a hole or notch in it through which byssus threads pass which attach it to a hard surface, usually a branch, leaf or aerial root of a mangrove tree.[3] The lower valve is curved so as to adhere closely to the surface on which it rests. Unlike most other bivalves, but like others in the genus, it has a single adductor muscle holding the two valves together.[4]
The morphology of the mangrove jingle shell depends on the nature of the substrate on which it has settled. When it is a juvenile the animal can and does move around, but later it becomes sessile. If it is on a mangrove leaf, the shell becomes flattened and more or less oval. However, on hard surfaces such as the branches of Avicennia and the aerial prop roots of Rhizophora, it is more domed and the animal orientates itself with regard to the water current and the axis of the wood.[5]
The mangrove jingle shell has two distinct colour varieties, one cream, usually found on the underside of mangrove leaves, and the other brownish purple and found on mangrove bark. At first it was thought that these represented two different species or two morphs occupying different habitats. However, in an experiment, cream-coloured shells were transplanted from leaves onto mangrove branches and began to change colour over the course of a few weeks. They became purplish-brown at the margins where new shell material was laid down. Other cream-coloured shells were left as controls on leaves and they showed no colour changes. The researchers concluded that the colour of the shell was not genetically controlled but was determined by the nature of the substrate on which the animal lived.[6]
Distributionedit
The mangrove jingle shell is found on coasts in the tropical Indo-Pacific Ocean, where it is a characteristic member of the mangrove community. The range extends from Malaya and the Philippines to the northern coast of Australia.[5]
Biologyedit
The mangrove jingle shell is a filter feeder. Like bivalves living in the intertidal zone on sandy beaches, this species feeds while the tide is in and it is submerged; otherwise it gathers food particles from splashes of sea water.[4]
Referencesedit
^ abRosenberg, Gary; Huber, Markus (2010). "Enigmonia aenigmatica (Holten, 1802)". WoRMS. World Register of Marine Species. Retrieved 2012-04-23.
^ abMorton, Brian (1976). "The biology, ecology and functional aspects of the organs of feeding and digestion of the S.E. Asian mangrove bivalve, Enigmonia aenigmatica (Mollusca: Anomiacea)". Journal of Zoology. 179 (4): 437–466. doi:10.1111/j.1469-7998.1976.tb02306.x.
^ abYonge, C. M. (1957). "Enigmonia aenigmatica Sowerby, a Motile Anomiid (Saddle Oyster)". Nature. 180 (4589): 765–766. Bibcode:1957Natur.180..765Y. doi:10.1038/180765a0. S2CID 4222635.
^Moss, Shaun M. (1993). Morten, Brian (ed.). Enigmonia aenigmatica: An enigmatic molluscan chameleon. The Marine Biology of the South China Sea: Proceedings of the First International Conference on the Marine Biology of Hong Kong and the South China Sea. Hong Kong University Press. pp. 605–611. ISBN978-9622093560.
December 15, 2023
enigmonia, genus, saltwater, clams, marine, bivalve, mollusc, family, anomiidae, jingle, shells, aenigmatica, mangrove, jingle, shell, clam, only, species, this, monotypic, genus, found, living, mangroves, indo, pacific, ocean, aenigmaticascientific, classific. Enigmonia is a genus of saltwater clams a marine bivalve mollusc in the family Anomiidae the jingle shells Enigmonia aenigmatica the mangrove jingle shell clam is the only species in this monotypic genus It is found living on mangroves in the Indo Pacific Ocean EnigmoniaEnigmonia aenigmaticaScientific classificationDomain EukaryotaKingdom AnimaliaPhylum MolluscaClass BivalviaOrder PectinidaFamily AnomiidaeGenus EnigmoniaIredale 1918 2 Species E aenigmaticaBinomial nameEnigmonia aenigmatica Holten 1802 1 Synonyms 1 Aenigma convexum Koch 1846 Aenigma corrugatumKoch 1846 Aenigma reticulatumKoch 1846 Anomia aenigmaticaHolten 1802 Anomia alfredensisTurton 1932 Anomia curiosaTurton 1932 Anomia farquhariTurton 1932 Anomia naviformisJonas 1847 Anomia oblongaTurton 1932 Anomia roseaGray 1825 Contents 1 Description 2 Distribution 3 Biology 4 ReferencesDescription editThe mangrove jingle shell clam can grow to a length of about 3 centimetres 1 2 in The shell is thin and delicate Although this species is a bivalve only the upper valve is normally visible and that valve is elongated or oval with a low dome and thus the general appearance which is like that of a limpet The umbone of the shell is off centre near the dorsal margin of the shell A few fine ridges radiate from the umbone and there is a sculpting of concentric growth rings The lower valve has a hole or notch in it through which byssus threads pass which attach it to a hard surface usually a branch leaf or aerial root of a mangrove tree 3 The lower valve is curved so as to adhere closely to the surface on which it rests Unlike most other bivalves but like others in the genus it has a single adductor muscle holding the two valves together 4 The morphology of the mangrove jingle shell depends on the nature of the substrate on which it has settled When it is a juvenile the animal can and does move around but later it becomes sessile If it is on a mangrove leaf the shell becomes flattened and more or less oval However on hard surfaces such as the branches of Avicennia and the aerial prop roots of Rhizophora it is more domed and the animal orientates itself with regard to the water current and the axis of the wood 5 The mangrove jingle shell has two distinct colour varieties one cream usually found on the underside of mangrove leaves and the other brownish purple and found on mangrove bark At first it was thought that these represented two different species or two morphs occupying different habitats However in an experiment cream coloured shells were transplanted from leaves onto mangrove branches and began to change colour over the course of a few weeks They became purplish brown at the margins where new shell material was laid down Other cream coloured shells were left as controls on leaves and they showed no colour changes The researchers concluded that the colour of the shell was not genetically controlled but was determined by the nature of the substrate on which the animal lived 6 Distribution editThe mangrove jingle shell is found on coasts in the tropical Indo Pacific Ocean where it is a characteristic member of the mangrove community The range extends from Malaya and the Philippines to the northern coast of Australia 5 Biology editThe mangrove jingle shell is a filter feeder Like bivalves living in the intertidal zone on sandy beaches this species feeds while the tide is in and it is submerged otherwise it gathers food particles from splashes of sea water 4 References edit a b Rosenberg Gary Huber Markus 2010 Enigmonia aenigmatica Holten 1802 WoRMS World Register of Marine Species Retrieved 2012 04 23 Tran Bastien 2010 Enigmonia Iredale 1918 WoRMS World Register of Marine Species Retrieved 2012 04 23 Mangrove jingle shell Enigmonia aenigmatica Wildsingapore Retrieved 2012 04 23 a b Morton Brian 1976 The biology ecology and functional aspects of the organs of feeding and digestion of the S E Asian mangrove bivalve Enigmonia aenigmatica Mollusca Anomiacea Journal of Zoology 179 4 437 466 doi 10 1111 j 1469 7998 1976 tb02306 x a b Yonge C M 1957 Enigmonia aenigmatica Sowerby a Motile Anomiid Saddle Oyster Nature 180 4589 765 766 Bibcode 1957Natur 180 765Y doi 10 1038 180765a0 S2CID 4222635 Moss Shaun M 1993 Morten Brian ed Enigmonia aenigmatica An enigmatic molluscan chameleon The Marine Biology of the South China Sea Proceedings of the First International Conference on the Marine Biology of Hong Kong and the South China Sea Hong Kong University Press pp 605 611 ISBN 978 9622093560 Retrieved from https en wikipedia org w index php title Enigmonia amp oldid 1180877639, wikipedia, wiki, book, books, library,
