A new family of the Hoplonemertea: Cinclidonemertes mooreae fam., gen. et sp. nov. (Nemertea: Hoplonemertea)

Abstract

Recent morphological, cladistic and molecular phylogenetic studies suggest a strong relationship between Cratenemertidae and Reptantia. In contrast to other hoplonemerteans, these groups have complex cerebral organs located behind the pre-cerebral septum possessing both sensory and “sac-type” epithelial components in the canal structure and a robust single-layered rhynchocoel wall composed of interwoven circular and longitudinal muscle fibres. Four specimens collected by the US Antarctic Program, listed in an earlier cladistic study as “Antarctic C”, distinct from other Hoplonemertea and related to Cratenemertidae and Reptantia, are described herein as Cinclidonemertes mooreae fam., gen. et sp. nov. They have complex cerebral organs, with the same two types of canal epithelium, lying against the sides of the brain and extending below and behind it ventrally, a lattice-like rhynchocoel wall with partial interweaving, and four large shallow cup-shaped eyes with little pigment as opposed to the numerous heavily pigmented deep-cup ocelli of Cratenemertidae and Reptantia.

Keywords:

• Cratenemertidae
• Reptantia
• Cinclidonemertes
• cerebral organs
• rhynchocoel wall
• pre-cerebral septum
• ocelli

Acknowledgements

This research was supported in part by two 2-year National Science Foundation US Antarctic Program grants (OPP-9509761) administered by the US National Museum of Natural History, Smithsonian Institution, and in part by a 5-year National Science Foundation grant (DEB-9712463) under the Partnerships for Enhancement of Expertise in Taxonomy program. Any opinions, findings, conclusions, or recommendations expressed herein are those of the author and do not necessarily reflect the views of the National Science Foundation.