Ontogenetic changes of the spiral cords as keys innovation of the muricid sculptural patterns: the example of the Muricopsis–Murexsul lineages (Gastropoda: Muricidae: Muricopsinae)

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“…Murexsul asper and M. queenslandicus both belong to a group of shells showing the assumed plesiomorphic condition of Murexsul, which comprises 19 Recent and fossil species from different parts of the world (Merle and Houart 2003). The plesiomorphic condition is assumed from the nature of the spiral sculpture (Merle and Houart 2003) determined from the condition in M. prionotus (Tate, 1888; Priabonian, Australia), which represents one of the oldest members of the genus (Merle 1999).…”

“…The plesiomorphic condition is assumed from the nature of the spiral sculpture (Merle and Houart 2003) determined from the condition in M. prionotus (Tate, 1888; Priabonian, Australia), which represents one of the oldest members of the genus (Merle 1999). The other Australian species included in that group are: M. diamantina (Houart, 1991), M. planiliratus (Reeve, 1845) and M. purpurispina (Ponder, 1972), but these species differ from the new species in shell length and other characters, especially in protoconch and spiral cord morphology.…”

“…This is highlighted by the Muricidae in the collection of the Australian Museum, Sydney, in which several little known or unknown species were found (Houart 1998;Houart 2004). Among these were two species belonging to a group of species previously studied by Merle and Houart (2003), many of which have been classified in Muricopsis (Murexsul) or in Murexsul s.s. by Houart (1988Houart ( , 1991Houart ( , 1993Houart ( , 1994Houart ( , 2001a.…”

The spiral cords of the Muricidae (Gastropoda, Neogastropoda): importance of ontogenetic and topological correspondences for delineating structural homologies

“…These latter species are representatives of primitive morphologies of the family (Harasewych 1984;Vokes 1992;Merle & Pacaud 2002a, b). Murexsul elatospira (Chattian, Aquitaine basin) and Murex (sensu stricto) tenuirostrum (Recent, New-Caledonia) are the most ornamented forms with the most complete series of primary cords corresponding to derived morphologies (Ponder & Vokes 1988;Merle & Houart 2003).…”

“…Fig. 2, with the P1 of X. kosugei) of a given cord during ontogeny influences the development of the cord spine (Merle & Houart 2003;Berrou et al 2004). In a second mode, differences in the development of one or several cord spines are not generated by differences in the development of the corresponding cord.…”