Lasioseius phytoseioides Chant
Creators: name: De Moraes, Gilberto J.
name: Abo-Shnaf, Reham I. A.
name: Pérez-Madruga, Yanebis
name: Sánchez, Leocadia
name: Karmakar, Krishna
name: Ho, Chyi-Chen
Publisher: name: Zenodo
Year: 2015
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Mesostigmata
Ascidae
Lasioseius
Lasioseius phytoseioides

description: Lasioseius phytoseioides Chant
(Figs 40–46)
Lasioseius phytoseioides Chant, 1963: 275.
Lasioseius phytoseioides.— Lindquist, 1964: 239; Kandil, 1980: 84. Lasioseius (Crinidens) phytoseioides.— Karg, 1980: 348.
Lasioseius (Cuspiacus) phytoseioides.— Christian & Karg, 2006: 227.
Specimens examined. female holotype collected in April, 1948 at Kentwood, Louisiana, USA, on clover.
Adult female (holotype female).
Dorsum of idiosoma (Fig. 40): dorsal shield 428 long and 318 wide at level of j6. Podonotal region of dorsal shield completely reticulate, with 13 pairs of setae (j2–j6, z2, z4, z5, s4–s6, r2, r3), a pair of distinct lyrifissures and three pairs of pores. Opisthonotal region completely reticulate, with 11 pairs of setae (J2, J4, J5, Z1, Z3–Z5, S2– S5), three pairs of distinct lyrifissures and three pairs of pores. Setae j5, j6, s4, s6, r2, r5, J2, J4, J5, Z1 short and smooth; j3, z2, S2, S3, S4 intermediate in length, smooth and stout; j2, j4, z4, z5, s5, r3, Z3–Z5, S5 longest, smooth and stout. Unsclerotised lateral cuticle beside dorsal shield with six pairs of setae (r5, R1–R5), short and smooth. Setal lengths: j2 44, j3 40, j4 37, j5 9, j6 20, J2 13, J4 18, J5 18, z2 24, z4 48, z5 44, Z1 9, Z3 75, Z4 68, Z5 79, s4 15, s5 55, s6 18, S2 22, S3 31, S4 35, S5 59, r2 11, r3 57, r5 11, R1 13, R2 15, R3 15, R4 22, R5 26.
Venter of idiosoma (Figs 41–42): base of tritosternum about 10 long and 8 wide at median level; laciniae about 75 long, divided for about 65% of their total length. Ventral shields reticulate; all setae aciculate and smooth. Presternal region transversely striate. Sternal shield 75 long, 97 wide at level of st2, bearing three pairs of setae (st1–st3) and two pairs of lyrifissures. Metasternal plate round to ellipsoid, bearing the fourth pair of sternal seta (st4) and a pair of lyrifissures (iv4). Genital shield 131 long, including the hyaline flap, 88 wide at posterior corners; bearing genital setae (st5); distance between genital setae 66; paragenital lyrifissures (iv5) on unsclerotised cuticle, posterolateral to st5. Ventrianal shield subtriangular, 165 long and 211 wide at widest level, bearing six pairs of opisthogastric setae (JV1–JV4, ZV2, ZV3) in addition to the circum-anal setae, a pair of marginal pores posterolateral to para-anal setae; anal opening small, 22 long including frame. Opisthogastric cuticle with a broken sclerotised line between genital and ventrianal shields, and two pairs of metapodal plates, the anterior smaller than the posterior. Unsclerotised cuticle around ventrianal shield with five pairs of lyrifissures and seta JV5. Exopodal plate distinct from anterior margin of coxa II to posterior margin of coxa IV. Length of ventral setae: st1 24, st2 20, st3 20, st4 22, st5 18, JV1 22, JV2 24, JV3 32, JV4 22, JV5 61, ZV2 20, ZV3 20, para-anal 15 and post-anal 31.
Peritrematic plate and peritreme: peritrematic plate fused with dorsal shield at level of j2 and broadly fused with exopodal plate beside coxa IV; peritreme extending forward to region between j2 setae.
Spermatheca (Fig. 43): calyx of spermatheca apparently swollen near atrium, then becoming slender, flaring slightly near vesicle.
Gnathosoma (Figs 44–45): general shape of chelicera as for the new characterisation of the phytoseioides group; fixed digit 32 long, bearing 13 teeth in addition to apical tooth; hyaline rim bearing 12-14 teeth; movable digit 35 long, bearing three teeth in addition to the apical tooth. Anteromedian region of epistome with three denticulate triangular extensions.
Legs (Fig. 46): leg pretarsi I–IV each with a pair of claws and pulvillus with three rounded lobules. Leg IV with three macrosetae: on genu (ad2) 55, basitarsus (pd3) 105 and telotarsus (pd2) 75, all smooth. Leg chaetotaxy (genu and tibia): II: 2, 3/1, 2/1, 2; 2, 2/1, 2/1, 2; III: 2, 2/1, 2/1, 1; 2, 1/1, 2/1, 1; IV: 2, 2/1, 3/0, 1; 2, 1/1, 3/1, 2.
Remarks. Seta s6 was not shown in the original description of the species. Walter & Lindquist (1997) suspected L. tabella to be a junior synonym of L. phytoseioides. However, our examination of specimens collected close to the type locality of L. tabella and of type specimens of L. phytoseioides led us to conclude that they are different species (s4 much shorter and s6 absent in L. chaudhrii = L. tabella).
description: Published as part of De Moraes, Gilberto J., Abo-Shnaf, Reham I. A., Pérez-Madruga, Yanebis, Sánchez, Leocadia, Karmakar, Krishna & Ho, Chyi-Chen, 2015, The Lasioseius phytoseioides species group (Acari: Blattisociidae): new characterisation, description of a new species, complementary notes on seven described species and a taxonomic key for the group, pp. 1-41 in Zootaxa 3980 (1) on pages 20-22, DOI: 10.11646/zootaxa.3980.1.1, http://zenodo.org/record/288988