Gamasellodes Athias -Henriot

De Moraes, Gilberto J., Britto, Erika P. J., Mineiro, Jefferson L. De C. & Halliday, Bruce, 2016, Catalogue of the mite families Ascidae Voigts & Oudemans, Blattisociidae Garman and Melicharidae Hirschmann (Acari: Mesostigmata), Zootaxa 4112 (1), pp. 1-299 : 22-23

Gamasellodes Athias -Henriot

FEMALE

Gnathosoma. Anterior margin of epistome most often with three pointed, smooth projections; some species with all or some of the projections distally denticulate; other species with two or four smooth and not distally denticulate projections, or with anterior margin convex or truncate, and denticulate. Usually h1 or h3 the longest and h2 the shortest of the hypostomatic and pc setae; insertion of h2 about in transverse line or slightly anterior to insertion of h3 (slightly posterior in G. tatricus Gwiazdowicz & Walter ). Inner palp trochanter seta not elongate. Deutosternum moderately wide, with subparallel delimiting lateral lines and seven rows (in the description of some species, 4–6) of 2–6 denticles each (one denticle in some rows in G. insignis (Hirschmann)) . Corniculi 1.5–2.5 times as long as their basal widths, with pointed tips, subparallel to slightly divergent distally. Palp tarsal apotele two-tined. Cheliceral digits of similar lengths; fixed digit with 4–6 teeth (eight in G. ericae Walter and apparently 12 in G. tatricus ) in addition to apical tooth; movable digit with two teeth in addition to apical tooth, without ventral projection.

Idiosoma. Elongate. Dorsum: podonotal and opisthonotal shields not fused, both usually mostly smooth (at least the posterior part of the opisthonotal shield strongly ornamented in some species), without transverse and nearly straight lines; some species with delineated strip along lateral margins of podonotal and opisthonotal shields. No supernumerary setae on dorsal shields or on unsclerotised lateral cuticle. Anterior end of podonotal shield not strongly deflexed; podonotal shield usually with 16 pairs of setae (s1 and s2 usually on unsclerotised lateral cuticle; 15 in G. hildae Jordaan , because z1 is absent; 17 in other species, because s1 is inserted on dorsal shield). Opisthonotal shield with 15 pairs of setae (14 in G. ericae , G. spinosus Bhattacharyya & Sanyal and an undescribed species from Colombia, because S1 is absent in the first two species and J4 is absent in the third); opisthonotal shield without posterior tubercles. Unsclerotised lateral cuticle with 5–13 pairs of setae (r -R, UR), including r3, which is often perpendicular to surface of idiosoma and distinctly longer than neighbouring setae. Most dorsal and lateral setae of idiosoma of similar lengths, short (often Z5 and less often other posterior setae of opisthosoma distinctly longer than other setae), acicular and smooth. Vent er: presternal platelets indistinct or lightly sclerotised as two lobes fused with sternal shield. Sternal shield with three pairs of setae of similar lengths (st1 inserted on lightly sclerotised presternal area in some species) and three pairs of lyrifissures (iv1–iv3; the latter on truncate to concave posterior shield margin); st2 about equidistant to st1 and st3. Seta st4 inserted on unsclerotised cuticle. Genital shield broadened or not posteriorly, including st5 (except in G. ericae ) but not iv5; posteriorly truncate to convex. One or two pairs of metapodal plates, the anterior usually elongate and transversely oriented, the posterior usually elongate and longitudinally oriented. Usually with 0–1 pair of elongate platelets and/or a sclerotised line between genital and anal shields (two pairs of elongate platelets in G. islandicus Bhattacharyya & Sanyal ). Opisthogaster with 6–10 pairs of setae in addition to circumanal setae, 3–4 pairs of which on the ellipsoidal to rounded ventrianal shield (anal shield, only with circumanal setae in G. ericae and G. tatricus ); ventrianal shield often strongly punctate posterolaterally to anal opening; para-anal setae inserted most often between levels of posterior margin and mid-length of anal opening, from slightly shorter than to less than half as long as post-anal seta, the latter not stout. Anal opening usually small, 1/4 to 1/7 of shield length (about 1/3 of shield length in G. ericae and G. tatricus ), usually in shield centre or posterior to it (slightly anterior to centre in G. ericae and G. tatricus ), away from posterior shield margin. Anterior section of endopodal shield usually normally developed and fused with sternal shield (reduced beside coxae I–II in G. ericae and G. seminudus (Ryke)) ; section behind sternal shield usually reduced to elongate platelet beside coxa IV (not shown in the original description of some species). Exopodal shield usually fragmented (a continuous strip along coxa II–IV in G. claudiae Walter ).

Peritreme. Extending from stigma to region between s1 and z1 (in some species shorter, to the extreme of just reaching posterior half of coxa II), about as wide as diameter of stigma. Peritrematic shield usually distinct, fused with dorsal shield at level between z1 and s1, or not fused with dorsal shield; tapering behind stigma, extending along part of posterior margin of coxa IV.

Legs. All legs with pretarsi. Setation of legs I–IV, femur: 12, 10 (or 11), 6, 6; genu: 13, 11, 8, 9; tibia: 13, 10, 8 (or 7), 10 (or 8). Leg II not distinctly different from other legs. Legs without macrosetae (with paired macrosetae on tarsus I of G. islandicus ).

Spermathecal apparatus. Usually distinct.

MALE

Gnathosoma similar to female, but movable digit with one tooth in addition to apical tooth; spermatodactyl about as long as or slightly longer than movable digit, directed forward, curved downward, and usually curved upward near narrower distal part. Dorsal shield with ornamentation similar to female, but broader, usually including s1; usually with fewer setae than female on unsclerotised lateral cuticle. Sternogenital shield with five pairs of setae (st1–st5) and three pairs of lyrifissures (iv1–iv3); not fused with ventrianal or peritrematic shields; posterior margin usually convex (truncate in G. spinosus ); with or without sclerites between sternogenital and ventrianal shields. Endopodal shield fused with sternogenital shield beside coxae I–III, apparently atrophied beside coxa IV. Metapodal plates present or not. Ventrianal shield usually semicircular, covering a considerable part or most of the opisthogastric surface, bearing 5–6 pairs of setae (when shield is partially eroded anteriorly) or seven pairs in addition to circumanal setae (only four pairs in the subrectangular, reduced shield of G. hildae ). Exopodal shield not fused with peritrematic shield, either an entire strip along coxae II–IV or strip interrupted near region between coxae II–III. Peritreme similar to female. Legs without spine-shaped setae.