Phylogenetic Relationships of Clawed Lobster Genera (Decapoda : Nephropidae) Based on Mitochondrial 16S rRNA Gene Sequences

Approximately 350 base pairs (bp) of the mitochondrial 16S rRNA gene were used to study the phylogenetic relationships among 5 genera of the clawed lobster family Nephropidae (infraorder Astacidea), including Homarus, Homarinus, Metanephrops, Nephrops, and Nephropsis. Maximum-parsimony analysis, using a hermit crab, Pagurus pollicaris (infraorder Anomura), as an outgroup. produced a tree topology in which Homarus and Nephrops formed a well-supported clade that excluded Homarinus. The same tree topology was obtained from both neighbor-joining and maximum-likelihood analyses, Some morphological characters that appear synapomorphic for Nephrops and Metanephrops may be due to convergence rather than symplesiomorphy. The current taxonomy, therefore, does not reflect the phylogeny of this group as suggested by the molecular data. More molecular data and studies using homologous morphological characters me needed to reach a better understanding of the phylogenetic history of clawed lobsters.

On the Identity of Spencebatea Abyssicola (Cumacea), with Additional Observations on the Genera Allied to Procampylaspis

In 1879 Norman described Spencebatea abyssicola, new genus, new species, on the basis of a single specimen from a deep-sea site off Ireland. The species was transferred to the genus Cumella by Stebbing in 1913, where it has remained. A reexamination of the specimen indicated that it belongs to the genus Procampylaspis since it possesses the recurved, tooth-bearing dactyl on maxilliped 2 which characterizes the genus. Seven other genera also exhibit modified dactyls on maxilliped 2, and, in addition, have styliform mandible molars, thus forming a coherent group within the family Nannastacidae.