A monograph on the isopod genus Colopisthus (Crustacea: Isopoda: Cirolanidae) with the description of a new genus Author MOORE, WENDY Author BRUSCA, RICHARD C. text Journal of Natural History 2003 2003-06-30 37 11 1329 1399 http://www.tandfonline.com/doi/abs/10.1080/00222930110108335 journal article 10.1080/00222930110108335 1464-5262 5260073 Colopisthus cavalier new species (figures 10–14) Material examined . H  , female ( USNM 285288 ) and six female paratypes ( USNM 285289 ); Barbuda , Spanish Point, intertidal beach wrack and live Porites ; Bredin Expedition 1958, Station 112a-58, collected by Smitt and Shuster ( USNM 217237 ) . Diagnosis . Lateral margins of cephalon and pereonite 1 with crenulations. Coxae 4–7 visible dorsally. Antenna 1 flagellum three-articulate. Antennae 2 flagellum sixarticulate. Pleon with one free pleonite and two fused pleonites (suture visible only in lateral view). Maxilliped endite with four circumplumose setae and three coupling setae. P-1 to P-3 merus with four to six molariform setae on inferior margin. Carpus of P-1 with four connate spines on inferior margin; P-2 and P-3 with three to five molariform setae and cuticular tubercles on inferior margin. Propodus of P-1 and P-2 with two complex setae and four or five connate spines. Pl-3 exopod with partial transverse suture. Uropodal exopod with two robust setae. Description of female Head . Lateral margins of cephalon and pereonite 1 with crenulations. Antennae . Antenna 1 peduncular articles 1–3 with biplumose setae, article 3 longest and narrowest, article 4 with slender and biplumose setae; flagellum threearticulate, first article much longer than distal two articles, all flagellar articles with slender setae and jointed aesthetascs, terminal article with biplumose seta. Antennae 2 peduncular articles 2–3 wider than long with slender setae only; article 4 subquadrate with biplumose and slender setae; article 5 longer than wide with three biplumose, one palmate and approximately 11 slender setae; flagellum six-articulate, all longer than wide, all with cluster of slender setae in anterior-distal region. Maxilliped . Endite with four circumplumose setae and three coupling setae. Palp article 1 medial margin with fine and slender setae; article 2 much wider than long, medial margin with slender setae; article 3 subquadrate with jointed slender setae on lateral and medial margins, article 4 subquadrate with one jointed slender seta on disto-lateral angle, two uniserrate and approximately four jointed slender setae on distal medial angle; terminal article length greater than width and with approximately four slender, one biplumose and two uniserrate apical setae. Maxillae . Maxilla 1 lateral lobe with one stout, seven forked and three uniserrate setae; medial lobe with two slender and three stout biplumose setae. Maxilla 2 outer lobe with three uniserrate apical setae, fine setae on lateral margin; medial lobe with four uniserrate setae; gnathal lobe apical margin with one large circumplumose, five stout biplumose and two slender setae; clusters of fine setae on medial and lateral margins. F. 10. Colopisthus cavalier , female holotype: (A) lateral aspect; (B) dorsal aspect. Mandible . Spine row with 11 large spines; molar process with approximately 16 small acute marginal spines; proximal palp article longer than wide with one slender seta on lateral margin; middle article with three slender, seven biserrate and four unequally biserrate setae; distal article with nine biserrate setae. Pereopods 1–3 . Ischium with one or two stout setae on inferior margin and one stout seta on superior-distal angle; P-3 with molariform seta near inferior-distal angle. Merus with cuticular tubercles on inferior margin, P-2 and P-3 with two molariform setae and a cluster of stout setae on distal angles; distal margin deeply incised (notched) on anterior surface. Carpus subtriangular, inferior margin much longer than superior margin; with cluster of stout setae on inferior distal angle; P-1 with four connate spines on inferior margin; P-2 and P-3 with three to five cuticular tubercles on inferior margin. Propodus with complex setae and connate spines on inferior margin as figured; P-1 and P-2 with two complex setae and four or five connate spines; P-3 with two complex setae and no connate spines; P-1 to P-3 superior distal angle with two slender setae, P-2 also with a biplumose seta. F. 11. Colopisthus cavalier , female holotype: (A) antenna 1; (B) antenna 2. F. 12. Colopisthus cavalier , female: (A) frontal lamina, clypeus, labrum, holotype; (B) maxilla 2; (C) right maxilliped, holotype; (D) right mandible, holotype; (E) maxilla 1. F. 13. Colopisthus cavalier , female holotype: (A, B) right pereopod 1; (C) right pereopod 2; (D) right pereopod 4; (E) right pereopod 5; (F) right pereopod 6; (G) right pereopod 3; (H) left pereopod 7; (I) left pereopod 7 carpus. F. 14. Colopisthus cavalier , female holotype: (A) left pleopod 5; (B) right uropod; (C) left pleopod 4; (D) telson-uropod; (E) right pleopod 1; (F) right pleopod 2; (G) right pleopod 3. Pereopods 4–7 . Basis with two biplumose setae at inferior distal angle. Ischium with two to four clusters of stout setae on inferior margin; P-4 with cuticular tubercles on inferior distal angle; P-5 and P-7 with two or three robust setae at superior-distal angle. Carpus of P-5 with one biplumose seta on anterior-distal margin, P-6 with two biplumose setae on anterior-distal margin and one biplumose seta on superior-distal angle, P-7 with seven biplumose setae on anterior-distal margin and approximately five long biplumose setae at superior-distal angle. Propodus superior-distal angle with stout and biplumose setae; P-4 to P-6 posteriordistal margin with one stout seta; inferior distal angle with two stout setae on P-4 and P-5 and one stout seta and one reduced complex seta on P-6 and P-7. Pleopods . Pl-1 to Pl-4 peduncle with three coupling setae on medial margin. Pl-3 to Pl-5 lateral margin of peduncle with one stout seta. Pl-3 exopod with partial transverse suture, Pl-4 and Pl-5 exopod with complete transverse suture. P1-1 to Pl-5 exopods with fine setae on proximo-lateral angle. Pl-1 to Pl-3 endopods with fine setae on proximo-medial angle. Pl-1 to Pl-4 endopods with approximately five PMS ; exopods with approximately 13–16 PMS . Pl-5 endopod subovate, without setation; exopod with approximately eight PMS . Uropod . Endopod with slender and palmate setae; two robust setae on medial margin and one robust seta on lateral margin; apex broadly rounded, with approximately four long slender setae. Exopod with slender setae and two robust setae on medial margin; apex rounded, with approximately three long slender setae; lateral margin with a continuous row of short slender setae; proximal lateral margin with dorsal fold. Distribution So far known only from Spanish Point, Barbuda , where it was collected from intertidal beach wrack and live Porites (a scleractinian coral). Remarks Known only from females. Etymology This species is named after Cavalier rum, a light golden rum of the islands of Barbuda and Antigua .