Amazonacarus setosus Vázquez, Araújo & Feres, 2014

Vázquez, Ma. Magdalena, Araújo, Marcel Santos De & Feres, Reinaldo José Fazzio, 2014, A new genus and two new species of Opilioacaridae (Acari: Parasitiformes) from Amazonia, Brazil with a key to world genera, Zootaxa 3814 (2), pp. 151-176 : 155-156

Amazonacarus setosus Vázquez, Araújo & Feres n. sp.

( Figs. 6–21 , 53 )

Diagnosis. Preanal segment XVIII with 4–6 setae dorsal plus 2 latero-ventral setae (5–6 dorsal setae in female, 4 in males) ( Figs. 15–16 ). Palp in adults with 10 foliate (= d) setae 26–31 thin, serrate and long setae on tibia not present in other species, not in such number nor in the size. Females with two large fine and acute eugenital setae. Males with a pair of large, quadrate glands surrounded by large, thick channel. Pregenital and genital areas in males with, respectively, 5 and 8 short slightly thickened acute setae.

Description. Based on 5 females and 2 males.

Gnathosoma . Chelicera ( Fig. 6 ). Basal segment with 1 seta, fixed digit with 3 lightly, serrate setae. Dorsal and antiaxial lyrifissures on fixed digit well developed. Fixed digit with 1 tooth, movable digit with 2 teeth and welldeveloped terminal hook. Movable digit in adults with 4 small, rounded ventral denticles (serrula).

Subcapitulum. ( Figs. 7–8 ). All 4 pairs of paralabial setae present: pl1 small, conical; With’s organ (pl2) membranous, discoid, rutellum (pl3) with 1 row of 5 teeth, inserted dorso-laterally; pl4 tiny, inserted dorsally. With 4 circumbuccal (cb) and 10 (males) or 13 (females) median and subcapitular (vm, lvm, ldm, vp, lvp) setae. Lateral lips with distinct canals (dl1 and/or dl2).

Palp ( Figs. 9–13 ). Trochanter with 5 spine-like, ribbed, tapering setae (= r - type); femur with 10 papilliform (= p - type) and 23–26 r - type setae; genu with 9 p- setae and 27 r - type setae in females; males with 6–7 p- and 20–24 r - type setae. Tibia with 26–31 thin, serrate and large (= s - type) and 44 r - type setae; 4–6 s - type setae distinctly elongate, positioned antero-ventral, extending to the base of the tarsal claws ( Fig. 10 ). Tibia and tarsus partially fused. Tarsus with 10 foliate (d), 6 v, 18–24 ch, 3 s, and 9 sm setae in females.

Idiosoma. Color: dark blue and violet stripes on body and legs. A relatively large species (1393–2065 µm).

Dorsum. Prodorsal shield in adults with 2 pairs of eyes and 86–102 stout, ribbed, “puffy” setae ( Fig. 14 ). Dorsal idiosoma between prodorsal shield and preanal segment without setae but with numerous lyrifissures arranged in transverse rows. Preanal segment (XVII) with 4–6 dorsal plus 2 latero-ventral setae (5–6 dorsal setae in females, 4 in males) ( Figs. 15–16 ). Anal plates each with 8–12 stout ribbed setae, higher numbers in females.

Sternitogenital region ( Figs. 17–18 ). Sternal verrucae each with 2–3 medium-long, barbed, tapering setae and 1 distinctly longer, barbed, tapering (st1) seta. Remaining sternal region with 3 pairs of stout, ribbed setae and, centrally, 1 pair of long tapering (st2) setae. Setae st3 stout, ribbed, not distinct from remaining sternal setae. With 3 pairs of lyrifissures. Pregenital capsules each with 1 long, tapering seta and 3 stout, ribbed setae. Pregenital and genital area in male with, respectively, 5 and 8 short, slightly thickened, acute setae. Both complexes of setae on small papillae. Pregenital area in females nude; a pair of fine, acute genital setae located under genital opening. Ovipositor ( Fig. 20 ) of “complex” type, with a pair of spiny lightly sclerotized projections, 2 small glands and a thick channel surrounding the ovipositor. Males with a pair of large quadrate glands surrounded by large, thick channel, with reel- like structures were close to glands ( Fig. 19 ).

Legs. Leg I longer than others. Tarsus I without a distinct acrotarsus, but with distinct basitarsus and telotarsus. Broad sensillum with “crown-like” tip distinctly distal to main group of sensory sensilla, but not adjacent to claws. Tarsus II with dorsal bifurcate seta and two smooth sensilla resembling solenidia.

Measurements: Idiosoma length 1393–2065, width 623–1096. Palps: trochanter 70–112, femur 125–190; genu 112–172; tibiotarsus 172–275. Rutella: 92–137. Chelicera: movable digit 62–102; median segment 177–257; basal segment 155–215. Legs. Leg I: trochanter 153–211, femur I 82 –95, femur II 597–840 genu 410–577, tibia 723–960, basitarsus 210–346, telotarsus ( Fig. 21 ) 329–452. Leg II: trochanter 153–211, femur 274–512, genu 156- 298, tíbia 159–335, basitarsus 197–350, telotarsus 184–280, acrotarsus 65–89. Leg III: trochanter I 105–163, trochanter II 85 –155, femur 218–417, genu 149–217, tibia 166–259, basitarsus 200–336, telotarsus 187–297, acrotarsus 66–82. Leg IV: trochanter I 168–274, trochanter II 114–271, femur 397–498, genu 260–363, tibia 295–482, basitarsus 271–444, telotarsus 224–358, acrotarsus 75–96.

Collection information. Holotype female, BRAZIL, Pará, Alter do Chão, coll. Franklin, E. & Ferreira, R., 20.VI.2000, ex littoral rainforest, sifted litter. Paratypes, same locality and collectors as the holotype. Deposition of types. Holotype female at INPA. Paratypes at INPA and DZSJRP.

Etymology. The specific name refers to setae on the penultimate segment.

Figures

FIGURE 21. Amazonacarus setosus n. sp. Female telotarsus I. Arrow: sensillum with crown-like tip.

FIGURES 6 – 8. Amazonacarus setosus n. sp. 6, lateral view of female chelicerae and detail of denticles (arrow: ventral denticles of another specimen). Ventral view of hypostome: 7, female; 8, male.

FIGURES 9 – 10. Amazonacarus setosus n. sp. Female. 9, palp tarsus, ventral (left) and dorsal (right) view. 10, palp tibia, ventral (left) and dorsal (right) view. Arrows indicate the unique length of this setae group in Opilioacaridae.

FIGURES 11 – 13. Amazonacarus setosus n. sp. Palp. Dorsal (left) and ventral (right) view of genu (11) and femur (12). 13, dorsal view of trochanter.

FIGURES 14 – 16. Amazonacarus setosus n. sp. 14, anterior view of dorsal shield. Dorsal view of preanal (XVIII segment) and anal segments: 15, female, 16, male (arrows show the dorsal setae on it).

FIGURES 17 – 18. Amazonacarus setosus n. sp. Ventral view of sternitogenital area: 17, female; 18, male.

FIGURES 19 – 20. Amazonacarus setosus n. sp. 19, ventral view of male glands (arrows: reel-like structure). 20, female invaginated ovipositor (arrow: genital setae).

FIGURES 51 – 53. 51, Caribeacarus panamensis. 52, Amazonacarus paraensis n. sp. 53, Amazonacarus setosus n. sp. Showing the group of setae s-type which are very large in A. setosus, but not in other species.