Jamieson, B.G.M. 1994j. Phylogeny of
the Brachyura
with particular reference to the Podotremata: evidence from a review of
spermatozoal ultrastructure (Crustacea, Decapoda). Philosophical
Transactions of the Royal Society London, B 345, 373-393.
Parsimony analysis, whether using
only spermatozoal characters orspermatozoal and
non-spermatozoal characters, suggests that: (i) the Brachyura is a
monophyletic taxon relative to the outgroup, three paguroids; (ii)
the Podotremata is a monophyletic taxon and the sister -group of the
heterotreme-thoracotreme assemblage; (iii) within the Podotremata, the
Dromiidae appears paraphyletic as its clade includes Paradynomene; (iv)
the Homolidae, is a monophyletic family; (v) the Raninoidea and
Cyclodorippoidea are sister groups within a monophyletic (unnamed) clade;
(vi) Latreillia sp. forms a polytomy with Homolidae +
Raninoidea-Cyclodorippoidea; and (vii) within the
heterotremethoracotreme
assemblage, the
Thoracotremata is a monophyletic taxon but the Heterotremata s.
strict. is a paraphyletic grouping. Analyses based on sperm data alone
differ from the combined data in not including the Homolidae in the
Archaeobrachyura (Homolidae + Raninoidea
-Cyclodorippoidea), thus the Dromiidae-Paradynomene + Homolidae +
Latreillia form a
polytomous clade which is the sister-group of the Raninoidea +
Cyclodorippoidea. Spermatozoal data also give majids the most
basal position in
the Heterotremata whereas for the combined data Neodorippe
(a shell carrier) appears the least modified member of the
heterotreme-thoracotreme assemblage. These findings are viewed in the
perspective of
other, notably molecular, studies. Spermatozoal synapomorphies are
listed and illustrated.