Notomastusbermejoi, a new species of Capitellidae (Annelida, Polychaeta) from the Gulf of California, with morphological remarks on species with hooks in thoracic chaetigers

Notomastusbermejoi sp. nov. from the Gulf of California shelf is described, illustrated, and compared with its congeners bearing hooded hooks in thoracic chaetigers. This new species is characterized by the presence of a prostomial palpode, only notopodia in the first chaetiger, hooded hooks in neuropodia of chaetiger 11, and its distinct methyl green staining pattern consisting of: chaetigers 1-4 slightly stained, chaetigers 5-10 with green bands encircling the segments, and a darker, solid, green band encircling the body in chaetigers 11-12. It is mainly distributed in the central Gulf of California in fine sand bottoms (62-96%) at 32-106.4 m depth, tolerating a wide range of temperature (13.2-17.59 °C), dissolved oxygen (0.8-4.93 ml/L), and organic carbon (3.0-7.2%). The type material and original descriptions of Notomastus species with hooks in thoracic chaetigers were examined; an identification key and tables with morphological distinctive characteristics, methyl green staining patterns, and geographic distribution of these close species are provided.

A new species of Notomastus (Annelida, Capitellidae) from southern China, with remarks on its morphology and distribution

The genus Notomastus is frequently encountered in Chinese waters. However, its species richness is poorly understood. In this study, a Notomastus species obtained from Xiamen Bay, southern China, was described and illustrated as a new species (N.sunaesp. nov.), based on morphological and molecular analyses. The new species is characterized by having uniramous chaetiger 1, the presence of palpode and eyespots on prostomium, chaetiger 11 with notopodial capillaries and neuropodial hooded hooks, and notopodial lobes with simple epithelial extensions on far posterior abdomen. With additional specimens collected from several localities along the southern coasts of China, the morphology and geographical distribution of the new species are discussed. A key is also provided for Notomastus species with neuropodial hooks in thoracic chaetiger 11.