| Summary: | Halearcturus gen. nov. Zoobank LSID. http://zoobank.org/ urn:lsid:zoobank. org:act: 80AB03F2-0DAD-4205-9831-B8F30D3D0757 Type species. Arcturus serrulatus Whitelegge, 1904, by monotypy and original designation (masculine). Diagnosis . Body weakly geniculate between pereonites 4 and 5, anterior pereon slightly elevated. Head with pair of submedian spines between eyes; pereonites with supracoxal spines on all pereonites, with paired sublateral tubercles, without paired submedian spines, without middorsal spines; pleonite 1 fused to remaining pleotelson; pleotelson with 2 middorsal tubercles near apex, without paired submedian spines, with pairs of sublateral tubercles, with marginal lateral projections, without prominent paired posterior sublateral spines more dominant than other spines, without prominent medial posterior spine dorsal to margin. Antennal flagellum of 2 articles, first about third as long as peduncle article 5, second quarter length of first. Pereopods 2–4 with regular row of long setae along flexor margins of merus-propodus, second row on mesial face. Pereopods 2–4 unguis short, curved. Pleopod 1 of male exopod groove opening distolaterally on margin, scarcely produced at opening. Pleopod 2 of male, appendix masculina acute, at least 1.5 times as long as endopod. Uropod without exopod. Oostegites 2–4 supported by ventral coxal processes, largest on pereonite 4; oostegite 5 absent, without ventral coxal processes. Etymology . For Herbert Mathew Hale (1895–1963) whose contributions significantly expanded knowledge of marine isopods in southern Australia, combined with Arcturus , a commonly used genus stem. Composition . Type species only. Remarks . Several characters set this genus and its only species apart from other antarcturids. Halearcturus serrulatus is unique in the family in having an antennal flagellum of one major article plus a short curved tapering second article; all other genera have either three or four articles, or about nine of similar lengths, plus a terminal one. The genus is ...
|
|---|