ASCIDAE

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 : 8-10

Diagnoses of Ascidae , Blattisociidae and Melicharidae

Figures 1–16 illustrate the structures mentioned in the subsequent diagnoses of the families and genera, as well as in the key provided to separate them.

ASCIDAE

FEMALE

Gnathosoma. Anterior margin of epistome variously shaped, smooth or denticulate. Ratios between lengths of hypostomatic and pc setae and insertion of h2 variable. Inner palp trochanter seta elongate or not. Deutosternum varying from narrow to wide, with delimiting lateral lines (very wide and without distinct lateral lines in Iphidozercon ). Corniculi 1–4 times as long as their basal widths (up to seven times as long as basal width in some Protogamasellus ), with pointed tips (distally divided in Anephiasca and some Protogamasellus ), well separated from each other and subparallel (slightly convergent distally in Gamasellodes and Protogamasellus ; convergent in Anephiasca , slightly divergent in Iphidonopsis , some Iphidozercon and some Leioseius ). Palp tarsal apotele bifurcate ( Ectoantennoseius with two tines normally developed and a third minute tine). Chelicera elongate in Xenoseius and Zerconopsis ; cheliceral digits of similar lengths or fixed digit slightly longer; fixed digit usually with 3–17 teeth (some Antennoseius with up to 26 teeth) in addition to apical tooth and a setiform pilus dentilis, and with differentiated processes in Anephiasca and Anystipalpus ; movable digit usually with two teeth (with 3–4 in some Antennoseius , Anystipalpus , Asca , Iphidozercon and Protogamasellus ), without ventral mucro (except in Antennoseius ).

Idiosoma. Usually elongate to ovoid (roundish in some Neojordensia ). Dorsum: podonotal and opisthonotal shields fused or not, smooth or ornamented; when fused, with or without distinct lateral incisions at region of fusion; without transverse and nearly straight lines (except in Protogamasellus ), delineated strip along lateral margins (except in some Gamasellodes and Iphidozercon ) or posterior tubercles (present in most Asca , except in Asca acornis ); anterior end of dorsal shield varying from not deflexed to strongly deflexed, concealing bases of j1 and z1. Usually no supernumerary setae on dorsal shield or on unsclerotised lateral cuticle (except in some Antennoseius , Anystipalpus , Asca , Neojordensia and Zerconopsis ). Podonotal region of shield (or podonotal shield) with 16–23 pairs of setae (some Antennoseius with up to 31 pairs). Opisthonotal region of shield (or opisthonotal shield) with 14–15 pairs of setae (13 pairs in some Arctoseius or up to 19 pairs in some Antennoseius , 16 pairs in Athiashenriotis and some Leioseius ; 19–22 pairs in Neojordensia ). Unsclerotised lateral cuticle usually with 4–13 pairs of setae (none in Neojordensia , two in Iphidonopsis , up to 16 pairs in some Anystipalpus , 8–43 in Antennoseius ); with or without UR setae. Vent er: with 0–1 pairs of presternal plates, which may be fused with sternal shield, or presternal area sclerotised as two lobes fused with sternal shield (a few pairs of fragmented plates in some Xenoseius ). Sternal shield usually with three pairs of setae (st1–st3; only two pairs in Neojordensia , some Anystipalpus , Arctoseius , Gamasellodes , Leioseius , Protogamasellus and in most Asca species; in Neojordensia and most Asca species, st1 inserted on presternal shields); usually st1–st3 of similar lengths and shapes; sternal shield with three pairs of lyrifissures (iv1–iv3; the latter usually on posterior shield margin, but on unsclerotised cuticle in Ectoantennoseius and in some Anephiasca and Protogamasellus ; at most with a pair of lyrifissures, iv2, in Anystipalpus ); posterior margin of sternal shield undulate, with a median lobe or varying from concave to convex. Seta st4 usually inserted on unsclerotised cuticle (absent in some Neojordensia ; inserted on lightly sclerotised platelets in some Protogamasellus ; shown as inserted on metasternal platelets in Arctoseius dendrophilus Karg , Asca pristis Karg and Leioseius naglitschi Karg ). Genital shield varying from very narrow to wide, usually not including genital lyrifissure (iv5; except in Neojordensia ), including or not st5; posterior region truncate to convex (tapering in some Antennoseius ). Usually with 1–2 pairs of metapodal plates (none in Maxinia , Neojordensia and some Protogamasellus ; three pairs in Leioseius brevisetosus Ishikawa). With or without sclerotised line or platelets between genital and anal shields. Opisthogaster usually with 7–10 pairs of setae (five pairs in Neojordensia and Protogamasellus scuticalis Genis, Loots & Ryke ; six pairs in Athiashenriotis , most Protogamasellus and some Gamasellodes ); with an anal shield bearing only circumanal setae, or with a ventrianal shield bearing additionally up to seven pairs of setae; para-anal setae usually inserted between levels of anterior and posterior margins of anal opening (anterior to anterior margin of anal opening in an undescribed Protogamasellus ); varying from about half as long as to about as long as post-anal seta (much shorter than postanal seta in Arctoseius ; longer than post-anal in some Protogamasellus ). Anal opening not enlarged (enlarged in Anephiasca ). Anterior section of endopodal shield varying from normally developed and fused with sternal shield to reduced to isolated fragments; section behind sternal shield varying from indistinct to a broad plate encircling part of coxae III–IV (plate fragmented in some Neojordensia ). Exopodal shield indistinct or distinct between coxae II–IV, sometimes fragmented or only distinct beside coxa IV.

Peritreme. Most commonly extending from stigma at least to level of dorsal seta s1 (reaching only level of coxa I in Maxinia , of coxa II in Protogamasellus and some Arctoseius , only level between s4–s 5 in Athiashenriotis ); with anterior end sharply recurved posteriorly in Iphidozercon ; about as wide as or narrower than diameter of stigma, wider than diameter of stigma in Iphidozercon and some Neojordensia ; with post-stigmatic extension in some Iphidozercon . Peritrematic shield usually wide (narrow in Protogamasellus , Xenoseius and some Arctoseius ); usually fused anteriorly with dorsal shield (not fused in Anephiasca , Protogamasellus and in some Arctoseius and Gamasellodes ); broadly fused with exopodal shield beside coxa IV (continuously fused with exopodal shield along its entire length in Anystipalpus and some Antennoseius ).

Legs. All legs with pretarsi (absent in Antennoseius (Antennoseius) and Anystipalpus ; vestigial in some Xenoseius ). Median section of pulvilli of legs II–IV rounded. Usual setation of legs I–IV, genu: 13 (12), 11 (10), 10 (8,9), 8 (9); tibia: 13 (12), 10 (9), 8 (9), 10 (9); setation sometimes reduced on tibia III: seven ( Arctoseius , Iphidozercon , Xenoseius , Zerconopsis and some Gamasellodes ); tibia IV: seven ( Iphidozercon , Xenoseius , Zerconopsis , Maxinia and most Arctoseius ) or six (some Arctoseius ). Leg II not distinctly different from other legs (except in some Zerconopsis , stouter). Legs with or without macrosetae.

Spermathecal apparatus. Laelapid-type; quite often not easily discernible.

MALE (not including: Anystipalpus and Athiashenriotis )

Fixed cheliceral digit with 2–14 teeth (17 in Ectoantennoseius ) in addition to apical tooth; movable digit usually with 1–2 teeth in addition to apical tooth (three in Protogamasellus keralaensis Bhattacharyya, Sanyal & Bhattacharya ); spermatodactyl usually from slightly shorter to slightly longer than movable digit (up to 2–3 times longer in Arctoseiodes , Asca and Iphidonopsis ). Sternogenital shield with five pairs of setae (st1–st5; st4 on or off the shield and st5 off the shield in Anephiasca , st5 also off the shield in some Antennoseius , Arctoseius and Asca ; st1 absent in Iphidozercon poststigmatus Gwiazdowicz ) and three pairs of lyrifissures (iv1–iv3; Maxinia without iv3). Usually with a ventrianal shield bearing 3–10 pairs of setae in addition to circumanal setae (some Arctoseius with separate ventral and anal shields). Legs similar to female, not enlarged; leg II with some spine-shaped setae in Anephiasca , Ectoantennoseius and some Arctoseius .

Figures

FIGURES 1 – 8. General morphology of members of the ascid complex (all females, except 8, male): 1. Dorsal idiosoma of a Lasioseius (Blattisociidae) species; 2. Ventral idiosoma of a Lasioseius species; 3. Dorsal gnathosoma of a Lasioseius species; 4. Ventral gnathosoma of a Lasioseius species (a: palp trochanter; b: corniculus; c: internal malae; d: deutosternum; h 1, h 2, h 3: hypostomal setae; pc: palpcoxal seta); 5 – 8. Antiaxial view of chelicera. 5. Female Lasioseius species (a: dorsal seta; b: dorsal lyrifissure; c: pilus dentilis; d: antiaxial lyrifissure); 6. Female Proctolaelaps species, Melicharidae (a: lobe; b: ventral mucro; c: hyaline rim); 7. Female Mucroseius species, Melicharidae (a: distal mucro); 8. Male, Lasioseius species (a: spermatodactyl). Not to scale.

FIGURES 9 – 16. General morphology of members of the ascid complex: 9. Phytoseiid-type sperm access system; 10. Laelapid-type sperm access system; 11. Pre-tarsus of a Lasioseius species; 12. Pre-tarsus of a Cheiroseius species; 13 – 16. Generalised legs, dorsal aspect. 13. Leg I; 14. Leg II, 15. Leg III; 16. Leg IV. Not to scale.