Willenstenhelia, Karanovic & Kim, 2014

Karanovic, Tomislav & Kim, Kichoon, 2014, New insights into polyphyly of the harpacticoid genus Delavalia (Crustacea, Copepoda) through morphological and molecular study of an unprecedented diversity of sympatric species in a small South Korean bay, Zootaxa 3783 (1), pp. 1-96 : 73

Genus Willenstenhelia gen. nov.

Type species. Willenstenhelia thalia sp. nov.

Other species. Delavalia minuta A. Scott, 1902 ; Stehelia (Delavalia) unisetosa Wells, 1967 ; Willenstenhelia urania sp. nov.; Willenstenhelia terpsichore sp. nov.

Etymology. The new genus name is dedicated to Dr. Elke Willen, formerly of the Deutsches Zentrum für Marine Biodiversitätsforschung, University of Oldenburg, Germany, for her contribution to the taxonomy and phylogeny of stenheliin miraciids. Her last name is prefixed to the existing genus name Stenhelia .

Diagnosis. Habitus robust but not spindle shaped in dorsal view, widest at posterior end of cephalothorax but with also very wide first two urosomites; podoplean boundary between prosome and urosome very conspicuous. Integument of all somites relatively weakly sclerotized, prosomites generally very smooth and urosomites with several parallel transverse rows of minute spinules, without cuticular windows or pits. Hyaline fringe of somites broad and smooth. Rostrum with dorsal transverse suture, bifid tip, pair of dorsal sensilla near tip, and pair of dorso-lateral pores near midlength; no spinules. Genital double-somite in female completely fused along ventral surface but with deep suture indicating original segmentation between genital and second urosomites dorsolaterally, dividing double-somite into equally long halves; anterior part inflated and with sharp and posteriorly directed cuticular process in vicinity of laterally placed genital apertures. Preanal somite with large and small spinules. Anal somite clefted medially at posterior half, with wide and almost trilobate anal operculum; ornamented with pair of large dorsal sensilla on anal operculum, posterior row of strong spinules on anal somite, and several large ventral spinules along medial cleft. Caudal rami more or less cylindrical, with slightly wider base, from three to five times as long as wide, completely smooth, and with seven setae (three lateral, one dorsal and three apical), all in posterior sixth of ramus length. Female antennula seven-segmented, but traces of ancestral division present on sixth segment, with distal posterior corner of first segment without spiniform process, and eighth segment with three lateral and two apical setae; no apical aesthetasc on ultimate segment. Male antennula strongly geniculate, nine-segmented, with additional large aesthetasc on third segment. Antenna composed of short coxa, strong allobasis, one-segmented endopod, and three-segmented exopod; endopod with two lateral spines flanking one slender seta. Mandibula without central seta on cutting edge, with six slender setae on small onesegmented endopod, and with three lateral and six apical setae on elongated and curved exopod; four apical exopodal setae strong and spiniform, one of them extremely long. Maxillula composed of praecoxa, coxa, basis, one-segmented endopod, and one-segmented exopod; endopod and exopod fused basally to basis, with two and four setae respectively; endopod wide distally. Maxilla composed of large syncoxa, small basis and even smaller one-segmented endopod; three coxal endites armature formula (starting from dorsal side) 2.3.3; basis with two lateral slender setae and two apical geniculate spines; endopod with four slender setae. Maxilliped not prehensile, three-segmented (two endopodal segments fused), with armature formula 0.3.4. All swimming legs of similar size and long in comparison to body length, with short spiniform processes on intercoxal sclerite and inner distal corner of basis of second to fourth leg, with all exopods three-segmented, endopod of first leg two-segmented, endopods of second to fourth legs three-segmented, except endopod of second leg in male with fused second and third segments; armature formula of exopods/endopods in female as follows: first leg, 0.1.022/1.211; second leg, 0.1.123/1.2.121; third leg, 0.1.223/1.1.121; fourth leg, 0.1.1(2)22(3)/1.0.121; inner seta on first endopodal segments of second and third legs slender; inner seta on first endopodal segment of fourth leg extremely strong and long; no sexual dimorphism in third leg; male second leg with three elements on ancestral third endopodal segment and inner apical seta shorter than outer spine; male fourth leg with very strong and characteristically curved outer spine on second exopodal segment. Female fifth legs fused medially, without posterior spinules or spiniform process on baseoendopod at base of exopod; endopodal lobe with only three elements but with large gap between innermost and two other ones; exopod more or less rectangular in shape, with wide base, about 1.5 times as long as wide, with five setae; innermost exopodal seta inserted on inner margin, while others more or less apical; central exopodal seta short and slender. Male fifth leg with fused endopodal lobes forming slightly convex plate, with two or three dissimilar spines on very narrow bump close to medial line and long posterior row of spinules between endopodal armature and exopod; exopod rectangular, with four or five elements, innermost one always inserted on inner margin, outermost one strong and spiniform. Female sixth leg minute flap covering genital aperture, with single short seta and two minute spines; sixth legs not joined with ventral suture, ventral surface of genital doublesomite completely smooth.