TWO NEW SPECIES OF THE DEEP-SEA GENUS NEOTANAIS BEDDARD, 1886 (TANAIDACEA: NEOTANAIDIDAE) FROM THE EASTERN CENTRAL PACIFIC

Abstract

We describe two new species of deep-water neotanaids collected from the Korea Deep Ocean Study (KODOS) Area in the eastern central Pacific. Neotanais pacificus is distinguished from other species of Neotanais by the following morphological combination: in the female: 1) pereiomere 5 is the longest of the pereiomeres, 2) distal claw of the cheliped fixed finger bulges outward, and the cutting edge descends steeply, 3) the uropod exopod is much longer than first endopodal article, 4) the setal row of the left mandible has bi-serrated setae and plumose seta, 5) the maxilliped endite bears three bipinnate spiniform setae on the inner posterior margin and medially expanded plumose seta on the distal margin, and 6) the propodi of pereipods 1 to 3 bear thick bi-pinnate spiniform setae. The female of N. capillus distinctly differs from other species of Neotanais by the following morphological combination: I) pereiomeres 4 and 5 are longer than wide, 2) the pleomeres are without midventral spurs, 3) the pleotelson bears fine setules along the distal margin, 4) the maxilliped endite has a very long plumose seta on the distal outer corner and two bipinnate spiniform setae on inner posterior margin, 5) the propodi of pereiopods I to 6 have thick bipinnate spiniform setae, and 6) the uropod is shorter than the pleon. In this study, distinct morphological characters differentiating the N. pacificus and N. capillus from other species of Neotanais are given on the basis of detailed descriptions.