![]() High rates of fishery bycatch clearly indicate a strong interaction between existing fisheries and sponge habitat. Furthermore, sponges are extremely fragile and easily damaged by contact with fishing gear. Examination of video footage collected along 127 km of the seafloor further indicate that there are likely hundreds of species still uncollected from the region, and many unknown to science. Submersible observations revealed that sponges, rather than deep-water corals, are the dominant feature shaping benthic habitats in the region and that they provide important refuge habitat for many species of fish and invertebrates including juvenile rockfish (Sebastes spp.) and king crabs (Lithodes sp). Clearly the deep-water sponge fauna of the Aleutian Islands is extraordinarily rich and largely understudied. Based on these collections and the published literature, we now confirm the presence of 125 species (or subspecies)of deep-water sponges in the Aleutian Islands. The first dedicated collections of deep-water (>80 m) sponges from the central Aleutian Islands revealed a rich fauna including 28 novel species and geographical range extensions for 53 others. Furthermore, the species presently recognized as Bathyraja parmifera exhibits two haplotypes among specimens from Alaska, suggesting the possibility of a second, cryptic species. Bathyraja panthera is diagnosed by its color pattern of light yellow blotches with black spotting on a greenish brown background, high thorn and vertebral counts, chondrological characters of the neurocranium and clasper, and a unique nucleotide sequence within the mitochondrial cytochrome oxidase gene. panthera isrestricted to the western Aleutian Islands. simoterus is restricted to waters around the northern and eastern coasts of Hokkaido, Japan and the new species B. smirnovi is a western Pacific species found in the Sea of Okhotsk and Sea of Japan B. Bathyraja parmifera is abundant in the eastern Bering Sea, Aleutian Islands, and northern Gulf of Alaska B. Species of Arctoraja are distributed across the North Pacific Ocean and adjacent seas from southern Japan to British Columbia. Although the nominal species of Arctoraja have all been considered synonyms of Bathyraja parmifera by various authors, on the basis of morphometric, meristic, chondrological, and molecular data we recognize four species, including the new species. Arctoraja was previouslyrecognized as a distinct subgenus of Breviraja and later synonymized with Bathyraja (family Rajidae). We also resurrect the skate subgenus Arctoraja Ishiyama, confirming its monophyly and the validity of the subgenus. We provide morphological and molecular evidence to recognize a new species of skate from the North Pacific, Bathyraja panthera. pingeli by a large eye, pigment on the lateral line and dorsal midline in flexion larvae, and a greater number of dorsal-fin rays and pectoral-fin rays once formed. Triglops nybelini is distinguished from T. pingeli larvae are distinguished from each other by meristic counts (vertebrae, dorsal-fin rays, and anal-fin rays once formed), number of postanal ventral melanophores, and first appearance and size of head spines. Among species co-occurring in the western North Atlantic Ocean, T. ![]() Triglops scepticus is differentiated from other eastern North Pacific Ocean larvae by having 0–3 postanal ventral melanophores, a large eye, and a large body depth. pingeli larvae are distinguished from each other by meristic counts and presence or absence of a series of postanal ventral melanophores. Among species co-occurring in the eastern North Pacific Ocean, T. Larval Triglops are characterized by a high myomere count (42–54), heavy dorsolateral pigmentation on the gut, and a pointed snout. xenostethus have yet to be identified and are thus not included in this paper. We examined larvae from collections of the Alaska Fisheries Science Center and Atlantic Reference Centre and used updated meristic data, pigment patterns, and morphological characters to identify larvae of Triglops forficatus, T. Prior to Pietsch’s (1993) revision of the genus Triglops, identification of their larvae was difficult six species co-occur in the eastern North Pacific Ocean and Bering Sea and three co-occur in the western North Atlantic Ocean.
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