Allocunaxa heveae

Heyer, Jacob Den & Castro, Tatiane Marie Martins Gomes De, 2008, A new Neotropical genus of the family Cunaxidae (Acari: Prostigmata: Bdelloidea), Zootaxa 1843, pp. 35-46 : 37-38

Allocunaxa heveae gen. et sp. nov.

Type-specimens (all on slides). Holotype male, rubber tree ( H. brasiliensis ), Pontes e Lacerda, State of Mato Grosso, (I. A. N. 873), Brazil, 21-I-2000, Ferla, N.J. deposited at “Musea de Zoologia Luiz de Queiroz”; paratype female, Solanum melongena L. ( Solanaceae ), Chiclaya Lambayeque (6º 51’S, 79º 49’W), Peru, 6- VIII-2006, Alvarado, A.D.G., deposited at “Museu de Zoologia Luiz de Queiroz”, Piracicaba; 1 paratype male, 1 molting paratype tritonymph (25-I-2005), 1 paratype female (5-IV-2004), 1 molting paratype tritonymph (7-VII-2004), 2 paratype protonymphs (29-VI-2004), 1 paratype protonymph (18-X-2004) and 1 paratype protonymph (9 –II-2005), all from H. brasiliensis, Plantações E., Michilin Ltda, Itiquira (17º23’S, 54º45’W), state of Mato Grosso, Brazil, Andrade, J.C. & Siqueira, L.M.S., deposited at DZBSJRP, São José do Rio Preto.

Diagnosis. Adults of this species can be identified by the strongly sclerotised gnathosoma and the presence of long prominent setae hg 3 borne on integumental protuberences.

Male (figs 1–9). Dimensions. Idiosoma : length 310(262–358), width 201(165–235); length hypognathum 115(112–117); width hypognathum 82(75–88); length palp 81(80–82); length chelicera 113(110–115); length leg I 209(205–213), leg II 214(195–223), leg III 254(248–260); leg IV 244(240–248); length sensillae vi 128(127–130), sce, 150(145–155); hg 3 39–42; trichobothrium leg IV 30.

Dorsum (figs. 1 and 2). Single trapezoid propodosomal shield poorly demarcated; only by surrounding striae. Sensillae vi and sce finely and densely pilose; sce shorter than vi. Setae ve somewhat longer than sci. Setae f 2 lacking. Setae c 2 positioned rather posteriad; seem closer in line to setae d 1 (fig. 1). Dorsal striae very finely papillated. Lateral shoulders, formed by coxae III, present. Anal region with cupules, 1 pair of para-anal and 1 pair of anal setae (fig. 2).

Ve n t e r (figs. 3 and 4). Coxal shields poorly demarcated. Only 6 (3 pairs) hysterogastral setae. Propodogastral setae just medioposteriad of coxae II. Paracoxal setae appear medially to and just off coxae IV (fig. 3). The genital valves poorly demarcated; provided with 4 pairs of g setae of which setae g 2 placed laterad to imaginary curved line connecting g 1, 3 and 4 (fig. 4). An everted aedeagus is present but its structure is not clearly defined.

Gnathosoma . Similar to female but smaller in dimensions. All parts are well-sclerotised and randomly finely papillated.

Legs (figs. 5–9). All legs are shorter than the body; I shortest, III longest. Tarsal lobes fairly well-developed. All leg segments provided with randomly placed papillae. Leg chaetotaxy: coxae I–IV 3 sts, 1 peg—1 sts—3 sts—1 sts; trochanters I–IV 1—1 —2—1 sts; basifemora I–IV 3—3 —4 or 3—0 sts; telofemora I–IV 4—4 —4—3 sts; genua I–IV (2 asl,1 sts), 2 asl, 4sts—(1 asl,1 sts),1 asl, 5 sts—2 asl, 4sts—1 asl, 4 sts; tibiae I–IV 2 asl, 5 sts—1 asl, 5 sts—1 asl, 5 sts—4 sts, 1 T; tarsi I–IV (1sts, 1 peo, 1 asl), 3 asl, 1 dtsl, 2 tsl, 7 sts, 2 spsts—1 asl,1dtsl, 1 tsl, 9 sts, 2spsts—1 tsl, 9 sts—1dtsts, 8 sts.

Female (figs. 10–18). Dimensions. Idiosoma : length 504(337–670) (bodies very much distended); width 378(285–470); length hypognathum 175; width hypognathum 138; length palp 119(118–120); length chelicera 153(148–163); length leg I 290(276–302); leg II 285(270–295); leg III 312(303–320,); leg IV 351(339– 363); length sensillae vi 155(145–163), sce 186, hg 3 59(50–65), trichobothrium IV 51.

Dorsum (fig. 10). The randomly papillated trapezoid shield is faintly demarcated (fig. 10). Resembles the male in most aspects as shield, striae, propodosomal and hysterosomal chaetotaxy, except in dimensions.

Ve n t e r (fig. 11). Resembles in general trends that of the male. It differs, however, in the number hysterogastral setae which is 8 (4 pairs). The genital valves are poorly demarcated and the papilla-patterns runs unbroken over the edges onto the surrounding integument (fig. 11).Two unequal genital papillae are present; the posterior pair being the smaller.

Gnathosoma (figs.12–14) Palp (fig. 12). The five-jointed palp displays a very interesting feature, viz. a (near) loss of the articulation facet between the telofemur and the genu. The remnant of this facet can only be observed as a narrow line between the mentioned segments. The papillae patterns runs unbroken over this line. Articulation facet of genu with tibiotarsus functional. The palpal chaetotaxy is as follows: trochanter (I), 0; basifemur (II), 1 dorsal long sts; telofemur (III), 1 shorter sts; genu (IV), 1 dorsal, 1 median,1 ventral and 1 lateral sts; tibiotarsus (V), 1 ventral sts, 1 median sts, 1 strong ventral tubercle, 1 ventral sts, 1 dorsal sts, 1 dtsl and 1 terminal claw.

Chelicerae (fig. 13). Trochanter broad, segment II tapers gradually towards the chelae. Cheliceral setae prominent. Immovable membranous digit reduced (fig. 13).

Hypognathum (fig. 14). No lateral lens-like structures (as occur in Dactyloscirus and Armascirus ). Setae hg 3 very long, prominent and borne on integumental protuberances (fig. 14). Hypostome (region anterior to setae hg 3) shorter than the coxal region (part posteriad to hg 3). Two pairs of prominent adoral setae (fig. 14).

Legs (figs. 15–18). Leg chaetotaxy: coxae I–IV 3 sts, 1 peg—1 sts—3 sts—1 sts; trochanters I– I 1 sts—1 sts—2 sts—1 sts; basifemora I–IV 3 sts—3 sts—3 sts –1 sts; telofemora I–IV 4 sts—4 sts—4 sts—4 sts; genua I–IV 4 asl, 5 sts—1 asl, 5 sts—1 asl, 5 sts—1 asl, 5 sts; tibiae I–IV 2 asl, 1 bsl, 5 sts—1 asl, 5 sts—1 asl, 5 sts—4 sts, 1 T; tarsi I–IV (1 sts,1 peo,1 asl), 3 asl, 1 dtsl, 2 tsl, 3 spsts, 10 sts—1 asl, 1 dtsl, 1 tsl, 3 spsts, 11 sts—1 tsl, 10 sts—10 sts.

Tritonymph (figs. 19–24). Dimensions: Idiosoma : length 425; width 300; length hypognathum 130; width hypognathum 85; length palp 86; length chelicerae 113; length legs I 230; leg II 225; leg III 257; leg IV 262; length sensillae vi 144, sce 170, trichobothria IV 50.

Dorsum (fig. 19). Except for dimensions and somewhat weaker sclerotisation it resembles the female. Figure 19 probably indicates more or less the form of the female. The trapezoid propodosomal plate resembles that of the male concerning form, position and relative length of setae, sensillae and papillae pattern. The hysterosomal chaetotaxy resembles that of the male.

Ve n t e r. Resembles that of the male except for dimensions and the genital region; 6 (3 pairs) of hysterogastral setae

Gnathosoma . Resembles that of the female but less sclerotised and smaller. The femur-genu joint of the palp is also fused.

Legs (figs. 20–24). All legs are shorter than the body; sequence II-I-III-IV. All leg segments are randomly papillated. Leg chaetotaxy: coxae I–IV 3 sts, 1 peg—1 sts—3sts—1sts; trochanters I–IV 1—1 —2—1 sts; basifemora I–IV 3—3 —3— 0 sts; telofemora I–IV 4 – 4 — 4 —4 sts; genua I–IV 3 asl, 1 short bsl, 5 sts—1 asl, 5 sts—1 asl, 5 sts—1 asl, 5 sts; tibiae I–IV 2 asl, 5 sts—1 asl, 5 sts—1 short bsl, 5 sts—4 sts, 1 T; tarsi I–IV (1 asl, 1peo,1 sts), 3 asl, 1 dtsl, 6sts, 2 spsts, 2 tsl—1 bsl, 1 dtsl, 8 sts, 1 tsl, 2 spsts —1 tsl, 9 sts—9 sts.

Protonymph (fig. 25). Dimensions: Idiosoma : length 258(238–275); width 181(168–213); length hypognathum 83(75–88); width hypognathum 69(65–71); length palp 60(55–63); length chelicera 84(80–85); length legs I 159(125–175); leg II 165(150–173); leg III 205(195–213); leg IV 197(170–210); length sensillae vi 92 (85–100), sce 111(100–125).

Idiosoma . Poorly sclerotised and smaller than the male. Dorsal shields non-existent. Venter with propodogastral and paracoxal setae. Genital region with one pair of genital setae flanking the genital opening.

Gnathosoma . Poorly sclerotised but typical for the species.

Legs (fig. 25). Basi – and telofemora IV being fused and lacking setae; tibiae IV lack trichobothria. Leg chaetotaxy: coxae I–IV 3 sts, 1 peg—1 sts—3sts—0 sts; trochanters I–IV 1—1 —2—0 sts; basifemora I–III 2—2 —1 sts; telofemora I–III 4 – 4 — 4 sts; genua I–IV 3 asl, 5 sts—1 asl, 5 sts—1 asl, 5 sts—1 asl; tibiae I– IV 2 asl, 5 sts—1 asl, 5 sts—1 short asl, 5 sts—0; tarsi I–IV (1 asl, 1peo,1 sts), 1 asl, 1 dtsl, 6sts, 2 spsts, 2 tsl—1 asl, 1 dtsl,1 tsl, 2 spsts, 6 sts— 1tsl, 8 sts—7 sts.

Etymology: This species is named for the plant species on which most of the specimens where associated with, viz. Hevea brasiliensis .

Figures

FIGURES 19 – 23. Allocunaxa heveae gen. et sp. nov. Tritonymph. 19 a. Dorsum. 19 b. Sensilla vi. 19 c. Sensilla sce. 20. Leg I. 21. Leg II. 22. Leg III. 23. Leg IV.