| Abstract |
A re-evaluation of the Dynomenidae Ortmann, 1892, on the basis of morphological characters, allows four subfamilies to
be recognised, viz. Acanthodromiinae n. subfam., Dynomeninae Ortmann, 1892, Metadynomeninae n. subfam., and
Paradynomeninae n. subfam. Sequences of character states for each homologous character (morphocline) show a similar
polarity. The Acanthodromiinae n. subfam. exhibits a plesiomorphic condition, both in body shape and fronto-orbital
disposition as well as in the condition of the thoracic sternum, abdominal holding mechanism and gill structure. Both the
Metadynomeninae n. subfam. and Dynomeninae are more advanced, the latter being more “carcinized” and the most
derived. The Paradynomeninae n. subfam. evolved a specialised frontal and buccal region, by forming a projecting
“face”. The family Dynomenidae, which presently comprises merely five extant genera and 21 species, but with a worldwide
distribution, is amongst the most ancestral brachyuran families, with a good fossil record from the Late Jurassic
onwards. A few fossil genera such as Kromtitis Müller, 1984, and Kierionopsis Davidson, 1966, appear to conform to the
Paradynomeninae n. subfam. A key to the subfamilies of extant Dynomenidae is provided.
Key words: Crustacea, Decapoda, Brachyura, Dynomenidae, podotremes, fossil Brachyura, new subfamilies |
