A new species of Ultratenuipalpus (Acari: Tenuipalpidae) from Cook Islands, with a key to the known species Author Xu, Yun Author Fan, Qing-Hai Author Zhang, Zhi-Qiang text Zootaxa 2013 3731 2 223 233 journal article 10.11646/zootaxa.3731.2.3 933215ad-5930-4b25-9c66-9b57c32559c4 1175-5326 223903 77466136-FA53-404D-B950-056CB809C610 Ultratenuipalpus avarua sp. nov. ( Figs. 1–7 ) Diagnosis. The adult female of Ultratenuipalpus avarua sp. nov. is readily distinguished from those of the other 24 species by rostral shield deeply cleft medially with 2 forked projections on each side; prodorsum smooth, divided into 5 regions, the prodorsal setae v 2 and sc 1, dorsalcentral setae c 1, d 1 and e 1 setiform and subequal; the dorsolateral setae e 3, f 3, h 2 and h 1 broadly lanceolate, subequal in length and about 7 times as long as setae d 3; triangular body projections present anterior to setae h 2 and h 1 on each side, and a broadly truncated projection between setae h 1. Type specimens. Holotype ♀. Cook Islands , Rarotonga, Avarua , 15 March , 1983, by Uri Gerson, ex. Cocos sp . ( Arecaceae ). Paratypes : 3♀, same collection data as holotype . The holotype and paratypes were deposited in New Zealand Arthropod Collection, Landcare Research, Auckland, New Zealand . Adult Female (n=4) Gnathosoma . ( Figs. 2 , 4 B) Gnathosoma reaching base of femur I, subcapitular setae m setiform, m = 14 (14– 16), m–m = 20 (20–21). Palp 4-segmented, setal formula: 0, 0, 2, 3; tibia with 2 bare setae near distal portion, tarsus with 2 eupathidia 5 (5–6), 6 and a companion seta. Idiosoma . ( Fig. 1 , 3 A, 6) 415 (415–425) long, 283 (277–283) wide. Rostral shield deeply cleft medially with 2 forked projections on each side. Idiosoma widest at posterior margin of propodosoma, narrowing abruptly at base of opisthosoma, then expanding posteriorly. PRODORSUM smooth, divided into 5 regions, bearing 3 pairs of prodorsal setae ( v 2 , sc 1 and sc 2) and 2 pairs of eyes ( Figs. 1 , 6 ). Setae v 2 and sc 1 setiform, sc 2 broadly lanceolate; lengths: v 2 7, sc 1 7 (7–8), sc 2 61 (61–67); distances: v 2– v 2 54 (53–54), sc 1– sc 1 136 (132–137), sc 1– sc 2 40 (40–47), sc 2– sc 2 222 (222–232). HYSTEROSOMA bearing 3 pairs of dorsalcentral setae ( c 1, d 1 and e 1), 1 pair of humeral seta c 3 and 5 pairs of dorsolateral setae ( d 3, e 3, f 3, h 2 and h 1). Triangular body projections present anterior to setae h 2 and h 1 on each side, and a broadly truncated projection between setae h 1 ( Fig. 1 , 6 ). Setae c 1, d 1 and e 1 setiform, subequal in length; setae d 3 lanceolate, c 3 leaf-like and about half as long as setae vR on trochanter III, and e 3, f 3, h 2 and h 1 broadly lanceolate, subequal in length and about 7 times as long as setae d 3. Lengths: c 1 8 (8–10), d 1 8, e 1 8 , c 3 29 (28–29), d 3 10 (10–12), e 3 71 (71–85), f 3 73 (73–82), h 2 73 (67–73), h 1 74 (74–81); distances: c 1– c 1 61 (61–63), d 1– d 1 57 (55–57), e 1– e 1 33 (32–33), d 3– e 3 103 (103–116), e 3– f 3 29 (28–29), f 3– h 2 26 (26–27), h 2– h 1 27 (27–30), h 1– h 1 67 (64–71). FIGURE 1. Ultratenuipalpus avarua sp. nov. (adult female). Dorsal view of idiosoma. FIGURE 2. Ultratenuipalpus avarua sp. nov. (adult female). Ventral view of idiosoma. FIGURE 3. Ultratenuipalpus avarua sp. nov. (adult female). A, dorsal setae; B, genital-anal plate. FIGURE 4. Ultratenuipalpus avarua sp. nov. (adult female). A, chelicerae and collar; B, subcapitulum; C, ventral setae. Venter. ( Fig. 2 , 3 B, 4C, 7) Venter with a few transverse striations between coxae II and III, fine transverse striations between setae 1a – 4a and dense round knots in lateral area of ventral idiosoma ( Fig. 7 ). All coxal setae setiform. Seta 1a and posterior medioventral seta 4a flagelliform, anterior medioventral seta 3a setiform. Length of 1a and 4a subequal, approximately 3.5 times as long as seta 3a ( Fig. 4 C). Lengths: 1a 77 (70–77), 3a 20 (20–22), 4a 71 (70–71). Distances: 1a – 1a 21 (21–29), 3a – 3a 46, 4 a– 4a 35 (35–40). Genital and ventral plates with flap of cuticles as shown in Fig. 3 B, bearing 1 pair of aggenital setae ag and 2 pairs of gential setae ( g 1 and g 2), setiform, g 1 and g 2 subequal. Anal plate with 3 pairs of pseudanal setae ( ps 1, ps 2 and ps 3). Setae lengths: ag 8 (8–9), g 1 13 (12– 14), g 2 13 (11–13), ps 1 27 (26–27), ps 2 17 (17–23), ps 3 8 (8–10). Distances: ag – ag 34 (32–34), g 1– g 1 11 (8–14), g 1– g 2 11 (8–12), ps 1– ps 2 9 (9–11). FIGURE 5. Ultratenuipalpus avarua sp. nov. (adult female). A, leg I; B, leg II; C, leg III; D, leg IV. Legs . ( Fig. 5 ) Lengths of legs I–IV: 207 (207–223), 176 (176–192), 170 (167–176), 176 (172–183). Chaetotaxy: I 2 , 1, 4, 3, 4, 8 + ω; II 2 , 1, 4, 3, 4, 8 + ω; III 1 , 2, 2, 1, 2, 5; IV 1 , 0, 1, 1, 2, 5. Most dorsal and lateral setae on trochanters, femora, genua and tibiae lanceolate, dorsal setae d on femora I and II broadly lanceolate and lateral setae l' on genua and tibiae setiform; ventral setae v setiform except on femora I and II barbed. Lateral setae l" on tibiae I–IV as long as corresponding tibiae. Setae ft ′ζ on tarsi I–IV flagelliform, much longer than others and about 1.5 times as long as corresponding tarsi; ft′′ setiform; unguinal setae u pectinate and equal in length. Lengths of solenidia: I ω 9, II ω 9 (8–9). Claws developed with tenent hairs on each side. Etymology. The species is named for its type locality Avarua and here treated as a noun in apposition.