Mucroseius Lindquist

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 : 47-48

Mucroseius Lindquist

FEMALE

Gnathosoma. Anterior margin of epistome usually with three projections (sometimes irregularly convex), denticulate. Seta h3 longest and h2 shortest of the hypostomatic and pc setae; h1 and pc similar in lengths; insertion of h 2 in transverse line with insertion of h3 or slightly anterior to it. Inner palp trochanter seta slightly longer than outer seta but not elongate. Deutosternum wide, with seven rows of denticles; with proximally divergent delimiting lateral lines extending from the most distal to the fifth rows of denticles; first four rows with 4–10 denticles, fifth and sixth rows with a larger number of denticles, seventh row with 0–7 denticles. Corniculi about 1.5–2.5 as long as their basal widths, with pointed tips, well separated from each other, subparallel; with or without a distinct membranous extension of the hypostome near the paraxial base of each corniculus. Palp tarsal apotele two-tined. Fixed cheliceral digit with 10–20 teeth about equally distributed along internal margin, an offset subapical tooth, a dorsodistal projection, an apical sensillus, an antiaxial expanded membranous lobe instead of setiform pilus dentilis, and a paraxial fringed hyaline rim near base of movable digit; movable digit with three teeth in addition to apical tooth and a ventral mucro near base.

Idiosoma. Broadly ovoid. Dorsum: podonotal and opisthonotal shields fused, smooth or ornamented, with or without lateral incisions; without transverse and nearly straight lines or delineated strip along lateral margins; anterior end of dorsal shield not strongly deflexed. No supernumerary setae on dorsal shield or on unsclerotised lateral cuticle. Podonotal region of shield with 20–23 pairs of setae, usually including r3 (sometimes inserted on unsclerotised lateral cuticle), which is similar to neighbouring setae. Opisthonotal region of shield with 15–19 pairs of setae. Unsclerotised lateral cuticle with 8–14 pairs of setae, including some UR setae. Most dorsal and lateral setae of idiosoma of similar lengths, from slightly shorter to distinctly longer than distance to subsequent setae, acicular and smooth (except Z5, usually sparsely barbed). Ve n t e r: presternal platelets indistinct. Sternal shield with three pairs of setae of similar lengths (st1–st3); st2 closer to st3 than to st1; posterior shield margin lightly sclerotised or slightly to deeply concave. Third pair of sternal lyrifissures (iv3) absent; seta st4 inserted on metasternal plates. Genital shield not wide enough to include iv5, but including st5; slightly convex posteriorly. Two pairs of metapodal plates, the anterior much smaller. No platelets between genital and anal shields. Opisthogaster with 9–10 pairs of setae on unsclerotised cuticle, in addition to circumanal setae; anal shield ovoid (longer axis longitudinal); para-anal setae inserted between levels of posterior margin and mid-length of anal opening, about half as long as post-anal seta. Anal opening enlarged, 1/3 of shield length, in shield centre or slightly anterior to it. Anterior section of endopodal shield fused with sternal shield; section behind sternal shield well developed, usually I-shaped, beside coxa IV. Exopodal shield distinct at least between coxae II and IV. Peritreme. Extending from stigma to level of s1 or slightly beyond, about as wide as diameter of stigma. Peritrematic shield narrow, fused with dorsal shield at level of s1 and fused by narrow bridge with exopodal shield next to coxa IV.

Legs. Setation of legs I–IV, genu: 13, 11, 9, 9; tibia: 13, 10, 8 (rarely 9), 10. Leg II not distinctly different from other legs. Legs I and IV with macrosetae.

Spermathecal apparatus. Not distinct.

NOTE: M. disparisetus Lindquist & Wu is found in two different morphs, the largest of which has disproportionately longer setae.

MALE: unknown.