New species and records of deep-water Orbiniidae (Annelida, Polychaeta) from the Eastern Pacific continental slope, abyssal Pacific Ocean, and the South China Sea Blake, James A. Zootaxa 2020 2020-02-03 4730 1 1 61 84PL5 Day 1977 [513,686,969,996] Polychaeta Orbiniidae Leitoscoloplos Animalia 5 6 Annelida genus    1A. Branchiae first present from a posterior thoracic setiger....................................................... 2  1B. Branchiae first present from an anterior abdominal setiger..................................................... 3   2A. With 12 thoracic setigers; branchiae from setiger 10; abdominal neuropodium with rounded tip and short ventral cirrus, subpodial flange absent; abdominal notopodia elongate, tapering to narrow tip; branchiae symmetrical, typically triangular, tapering to papillate tip.................................................................  Leitoscoloplos sahlingi  n. sp.  2B. With 14 thoracic setigers; branchiae from setigers 11–12; abdominal neuropodium with bi-lobed tip; subpodial flange present; abdominal notopodia elongate, with subdistal swelling; branchiae asymmetrical..  Leitoscoloplos mexicanus( Fauchald, 1972)   3A. Pre-setiger region long, narrow, triangular, longer than wide................................................... 4  3B. Pre-setiger region short, as wide as or wider than long........................................................ 5   4A. Furcate setae present; branchiae from setiger 15–16; thoracic noto- and neuropodial postsetal lamellae short, triangular, tapering, arising from low base; abdominal neuropodia without subpodial flange.................  Leitoscoloplos cliffordi  n. sp.  4B Furcate setae absent; branchiae from setiger 17–18; thoracic noto- and neuropodial postsetal lamellae long, digitiform, arising from broadly rounded base; abdominal neuropodia with protruding subpodial flange.......  Leitoscoloplos williamsae  n. sp.   5A. Prostomium distinctly separated from peristomium by groove; branchiae elongate, smooth, triangular, tapering to narrow tip ................................................................................................... 6  5B. Prostomium merging posteriorly with peristomium; branchiae short, thick, with glandular appearance...........................................................................  Leitoscoloplos pachybranchiatus Blake & Hilbig, 1990   6A Thoracic notopodial postsetal lamellae triangular; abdominal neuropodia with blunt tip with two weakly developed lobes, ventral cirrus absent; subpodial flange absent.........................................  Leitoscoloplos gordaensis  n. sp.  6B. Thoracic notopodial postsetal lamellae elongate, digitiform, arising from swollen base; abdominal neuropodia with rounded tip and subterminal ventral cirrus; subpodial flange present................................  Leitoscoloplos lunulus  n. sp.