Anomalodesmata

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. purmamarcensis S06
    `--+--Pholadomyoida SV03
       `--+--Archanodontidae [Archanodontoidea] M96
          |    |--Archanodon jukesi (Forbes 1853) SB93
          |    `--Neamnigenia SB93
          |         |--N. beljanini Khalfin 1950 SB93
          |         `--N. longa Betekhtina 1966 SB93
          `--Modiomorphoida SV03
               |  i. s.: Lyromytilus attenuatus JB12
               |         Allodesmatidae JB12
               |           |--Ischyrodonta JB12
               |           `--Allodesma Ulrich 1894 C04
               |         Mecynodontidae S06
               |           |--Mecynodon SB93
               |           |    |--M. carinatus (Goldfuss 1837) SB93
               |           |    `--M. oblongus (Goldfuss 1837) SB93
               |           `--Goniophora Phillips 1848 S06
               |                |--G. chemungensis S06
               |                |--G. (Cosmogoniophora) extensa Cope 1996 S06
               |                `--G. pravinasuta Johnston 1993 S06
               |         Goniophorinidae S06
               |           |--Lossella Sánchez 2006 S06
               |           |    `--*L. juancruzi Sánchez 2006 S06
               |           `--Goniophorina Isberg 1934 SV03 [incl. Cosmogoniophorina Isberg 1934 S06, SV03]
               |                |--*G. volvens Isberg 1934 S06
               |                |--G. carinata (Isberg 1934) [=*Cosmogoniophorina carinata] SV03
               |                `--G. tenuicostata Harrington 1938 [=G. (Cosmogoniophorina) tenuicostata] SV03
               |         Colpomyidae SB93
               |           |--Colpantyx woolleyi Pojeta & Gilbert-Tomlinson 1977 SB93
               |           `--Xestoconcha kraciukae Pojeta & Gilbert-Tomlinson 1977 SB93
               |         Orthonotidae SB93
               |           |--Orthonote Conrad 1841 M65
               |           `--Palaeosolen TW07
               |--Modiomorphidae [Modiomorphoidea] S06
               |    |--Modiomorpha Hall 1869 S06
               |    `--Megalomoidea canadensis (Hall 1852) SB93
               `--Kalenteroidea H00
                    |--Kalenteridae SB93
                    |    |--Rimmyjimima arcula Chronic 1952 SB93
                    |    `--Kalentera flemingi Marwick 1953 SB93
                    `--Permophoridae H00
                         |--Permophorus JB12
                         |--Pleurodapis multicincta Clarke 1913 SB93
                         |--Neocypricardinia Liu 1976 ZP86
                         |    |--N. simplex Zhang & Pojeta 1986 ZP86
                         |    |--N. sinensis ZP86
                         |    `--N. subelegans ZP86
                         `--Myoconcha Sowerby 1824 [Myoconchinae] H00
                              |--M. (Myoconcha) [incl. Labayophorus Likharev 1939] H00
                              |    |--*M. (M.) crassa Sowerby 1824 H00
                              |    |--‘*Labayophorus’ magnus Likharev 1939 H00
                              |    `--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

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

REFERENCES

[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.

[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.

Last updated: 5 March 2022.