Myoconcha crassa, from Bajocien 14.

Belongs within: Bivalvia.
Contains: Pholadomyoida.

The Anomalodesmata are a clade of bivalves characterised by a reduced hinge dentition. Despite not being among the most speciose groups of bivalves, anomalodesmatans encompass a surprising amount of ecological and morphological diversity, including (among others) endolithic rock-borers, some of which form rather un-bivalve-like tubes, and active predators. Stem representatives of the Anomalodesmata may be found among the Palaeozoic order Modiomorphoida, characterised by an actinodont hinge with radial, poorly differentiated teeth. Modiomorphoids are somewhat similar in appearance to modern mussels to which they have alternatively been suggested to be related. However, unlike mussels, they probably lacked an attaching byssus. The Carboniferous to Cretaceous Kalenteroidea possessed trapezoidal to modioliform shells with the anterior and pedal muscle scars on thickened buttresses. The Ordovician to Silurian Lipanellidae have a shell with predominantly radial ornamentation, an edentulous hinge and no byssal sinus (Sánchez 2006). An edentulous hinge is also characteristic of the Archanodontidae, large freshwater bivalves known from the Upper Devonian to the Permian.

<==Anomalodesmata [Conocardiiformii]
    |--Lipanella [Lipanellidae]S06
    |    `--L. purmamarcensisS06
       `--+--Archanodontidae [Archanodontoidea]M96
          |    |--Archanodon jukesi (Forbes 1853)SB93
          |    `--NeamnigeniaSB93
          |         |--N. beljanini Khalfin 1950SB93
          |         `--N. longa Betekhtina 1966SB93
               |  i. s.: Lyromytilus attenuatusJB12
               |         AllodesmatidaeJB12
               |           |--IschyrodontaJB12
               |           `--Allodesma Ulrich 1894C04
               |         MecynodontidaeS06
               |           |--MecynodonSB93
               |           |    |--M. carinatus (Goldfuss 1837)SB93
               |           |    `--M. oblongus (Goldfuss 1837)SB93
               |           `--Goniophora Phillips 1848S06
               |                |--G. chemungensisS06
               |                |--G. (Cosmogoniophora) extensa Cope 1996S06
               |                `--G. pravinasuta Johnston 1993S06
               |         GoniophorinidaeS06
               |           |--Lossella Sánchez 2006S06
               |           |    `--*L. juancruzi Sánchez 2006S06
               |           `--Goniophorina Isberg 1934SV03 [incl. Cosmogoniophorina Isberg 1934S06, SV03]
               |                |--*G. volvens Isberg 1934S06
               |                |--G. carinata (Isberg 1934) [=*Cosmogoniophorina carinata]SV03
               |                `--G. tenuicostata Harrington 1938 [=G. (Cosmogoniophorina) tenuicostata]SV03
               |         ColpomyidaeSB93
               |           |--Colpantyx woolleyi Pojeta & Gilbert-Tomlinson 1977SB93
               |           `--Xestoconcha kraciukae Pojeta & Gilbert-Tomlinson 1977SB93
               |         OrthonotidaeSB93
               |           |--Orthonote Conrad 1841M65
               |           `--PalaeosolenTW07
               |--Modiomorphidae [Modiomorphoidea]S06
               |    |--Modiomorpha Hall 1869S06
               |    `--Megalomoidea canadensis (Hall 1852)SB93
                    |    |--Rimmyjimima arcula Chronic 1952SB93
                    |    `--Kalentera flemingi Marwick 1953SB93
                         |--Pleurodapis multicincta Clarke 1913SB93
                         |--Neocypricardinia Liu 1976ZP86
                         |    |--N. simplex Zhang & Pojeta 1986ZP86
                         |    |--N. sinensisZP86
                         |    `--N. subelegansZP86
                         |--Myoconcha Sowerby 1824 [Myoconchinae]H00
                         |    |--M. (Myoconcha) [incl. Labayophorus Likharev 1939]H00
                         |    |    |--*M. (M.) crassa Sowerby 1824H00
                         |    |    |--*Labayophorus’ magnus Likharev 1939H00
                         |    |    `--M. (M.) psilonoti Quenstedt 1856 (see below for synonymy)H00
                         |    `--M. (Modiolina Müller 1851)H00
                         |         |--‘Lithodomus’ discrepans Müller 1847 [incl. *Modiolina bosqueti Müller 1851]H00
                         |         `--M. (M.) decorata (Münster in Goldfuss 1837) (see below for synonymy)H00
                              |--S. compressaF71
                              |--S. costata [=Cardinia costata]F71
                              |--S. farleyensis Etheridge 1900F71
                              |--S. obliqua Etheridge 1900F71
                              |--S. praerupta (Dana 1849) [=Cypricardia praerupta]F71
                              |--S. recta (Dana 1849) [=Cardinia recta]F71
                              |--S. simplex (Dana 1849) [=Cypricardia simplex]F71
                              `--S. veneris [=Cypricardia veneris]F71

Myoconcha (Modiolina) decorata (Münster in Goldfuss 1837) [=Mytilus decoratus; incl. Modiola lithodomus Koch & Dunker 1837, Myoconcha oxynoti Quenstedt 1856]H00

Myoconcha (Myoconcha) psilonoti Quenstedt 1856 [incl. M. scabra Terquem & Piette 1865, M. scalprum d’Orbigny 1849 (n. d.)]H00

*Type species of generic name indicated


[BRW98] Beesley, P. L., G. J. B. Ross & A. Wells (eds) 1998. Fauna of Australia vol. 5. Mollusca: The Southern Synthesis. Part A. Australian Biological Resources Study: Canberra.

[C04] Cope, J. C. W. 2004. Bivalve and rostroconch mollusks. In: Webby, B. D., F. Paris, M. L. Droser & I. G. Percival (eds) The Great Ordovician Biodiversification Event pp. 196–208. Columbia University Press.

[F71] Fletcher, H. O. 1971. Catalogue of type specimens of fossils in the Australian Museum, Sydney. Australian Museum Memoir 13: 1–167.

[H00] Hodges, P. 2000. The Early Jurassic Bivalvia from the Hettangian and Lower Sinemurian of south-west Britain. Part. 1. Monograph of the Paleontographical Society 614: 1–64.

[JB12] Johnson, M. E., & B. G. Baarli. 2012. Development of intertidal biotas through Phanerozoic time. In: Talent, J. A. (ed.) Earth and Life: Global biodiversity, extinction intervals and biogeographic perturbations through time pp. 63–128. Springer.

[M65] Moore, R. C. (ed.) 1965. Treatise on Invertebrate Paleontology pt H. Brachiopoda vol. 2. The Geological Society of America, Inc.: Boulder (Colorado), and The University of Kansas Press: Lawrence (Kansas).

[M96] Morton, B. 1996. The evolutionary history of the Bivalvia. In: Taylor, J. D. (ed.) Origin and Evolutionary Radiation of the Mollusca pp. 337–359. Oxford University Press: Oxford.

[S06] Sánchez, T. M. 2006. Taxonomic position and phylogenetic relationships of the bivalve Goniophorina Isberg, 1934, and related genera from the early Ordovician of northwestern Argentina. Ameghiniana 43 (1): 113–122.

[SV03] Sánchez, T. M., & N. E. Vaccari. 2003. Ucumariidae new family (Bivalvia, Anomalodesmata) and other bivalves from the Early Ordovician (Tremadocian) of northwestern Argentina. Ameghiniana 40 (3): 415–424.

[SB93] Skelton, P. W., & M. J. Benton. 1993. Mollusca: Rostroconchia, Scaphopoda and Bivalvia. In: Benton, M. J. (ed.) The Fossil Record 2 pp. 237–263. Chapman & Hall: London.

[TW07] Taylor, J. D., S. T. Williams, E. A. Glover & P. Dyal. 2007. A molecular phylogeny of heterodont bivalves (Mollusca: Bivalvia: Heterodonta): new analyses of 18S and 28S rRNA genes. Zoologica Scripta 36 (6): 587–606.

[ZP86] Zhang, R., & J. Pojeta Jr. 1986. New bivalves from the Datang Stage, Lower Carboniferous, Guangdong Province, China. Journal of Paleontology 60 (3): 669–679.

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