PRELIMINARY CLADISTIC ANALYSES OF RELATIONSHIPS AMONG LOLIGINID SQUIDS (CEPHALOPODA, MYOPSIDA) BASED ON MORPHOLOGICAL DATA

Most species in the cephalopod taxon Loliginidae have a near-shore hab itat and are commercially important, yet phylogenetic relationships wi thin the group have not been examined. In this study, relationships am ong loliginid species are analyzed using cladistic methods. Forty-eigh t morphological characters for 48 species (40 loliginid species and ei ght outgroup taxa) were collected through examination of museum specim ens and primary literature and coded into a matrix for cladistic analy sis. Both unweighted and successive weighting maximum-parsimony analys es were undertaken, and the phylogenetic signal of the data was evalua ted. Unweighted analyses support the hypothesis of monophyly for Lolig inidae, and suggest some well-supported sister species and crown-clade relationships (such as Alloteuthis Wulker and Sepioteuthis Blainville ), but the positions of these groups relative to one another cannot be resolved due to the large number of most-parsimonious trees. Successi ve weighting analyses showed support for some additional major clades (Photololigo Natsukari and Nipponololigo Natsukari), and provided insi ght into the cladistic information value of the characters in the anal ysis. Continued collection of morphological and internal anatomical da ta for these species for all stages of the life cycle, as well as the addition of molecular data to the analysis, could help resolve relatio nships within the group.