Lasioseius youcefi Athias-Henriot
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 youcefi

description: Lasioseius youcefi Athias-Henriot
(Figs 69–77)
Lasioseius youcefi Athias-Henriot, 1959: 177.
Lasioseius youcefi.— Hirschmann, 1962: 30; Bregetova, 1977: 178; Tseng, 1978: 124; Walter & Lindquist, 1989: 2800; Karg, 1993: 254; Kamali et al., 2001: 8; Halliday, 2005: 21; Gwiazdowicz, 2007: 88; Christian & Karg, 2008: 69; Zhang & Fan, 2010: 284, Negm, 2014: 116.
Lasioseius mcgregori Chant, 1963: 276 [Junior synonym of L. youcefi by Walter & Lindquist, 1989: 2800; Christian & Karg, 2006: 219].
Lasioseius (Lasioseius) paucisetosus Westerboer, 1963: 220 [Junior synonym of L. youcefi by Bregetova, 1977: 178; Karg, 1980: 364; Walter & Lindquist, 1989: 2800; Christian & Karg, 2006: 219].
Lasioseius mcgregori.— Lindquist, 1964: 242; Bregetova, 1977: 179; Kandil, 1980: 85; Gupta, 2003: 5.
Lasioseius (Lasioseius) proteae Ryke, 1964: 343 [Junior synonym of L. youcefi by Karg, 1980: 364; Walter & Lindquist, 1989: 2800; Christian & Karg, 2006: 219].
Lasioseius paucisetosus. — Karg, 1965: 206; 1971: 250; Lapinya, 1976: 80 (Figs 12, 13 but not 14, 15). Lasioseius lasiodactyli Ishikawa, 1969: 112 [Junior synonym of L. youcefi by Christian & Karg, 2006: 219] Lasioseius (Criniacus) mcgregori.— Karg, 1980: 362.
Lasioseius (Criniacus) youcefi.— Karg, 1980: 364.
Lasioseius peritremus Nasr & Abou-Awad, in Zaher, 1986: 70 [Junior synonym of L. youcefi by Gwiazdowicz, 2007: 80]. Lasioseius peritremus.— Nasr & Abou-Awad, 1987a: 31; Nasr & Abou-Awad, 1987b: 89; Fouly, 1997: 2. Lasioseius (Crinidens) peritremus.— Christian & Karg, 2006: 152.
Lasioseius (Cuspiacus) youcefi.— Christian & Karg, 2006: 219.
Specimens examined. France —three adult females from weeds, collected by F. Faraji, at Lot-et-Garonne, South- West, May 27, 2006. United Arab Emirates —Six adult females from Bermuda grass, collected by M.W. Negm, at Dubai, January, 2013.
Adult female (specimens measured: United Arab Emirates—six, France—three).
Measurements of structures given in Table 3.
Dorsum of idiosoma (Fig. 69): podonotal region of dorsal shield reticulate, with 12 pairs of setae (j2–j6, z2, z4, z5, s4–s6, r3), two pairs of distinct lyrifissures and three pairs of pores. Opisthonotal region reticulate, with 11 pairs of setae (J2, J4, J5, Z1, Z3–Z5, S2–S5), seven pairs of distinct lyrifissures and two pairs of pores. Seta J5 short and smooth; j2, z2, s4, s6, J2, J4, S2–S4 intermediate in length, smooth and stout; j3–j6, z4, z5 intermediate in length, lightly serrate and stout; s5, r3, Z1, Z3–Z5, S5 longest, lightly serrate and stout. Unsclerotised lateral cuticle beside dorsal shield with six pairs of setae (r5, R1–R 5), all short and smooth.
Venter of idiosoma (Figs 70–71): all setae aciculate and smooth, except for JV5, lightly serrate. Base of tritosternum about 16 (14–18) long and 8 (6–10) wide at median level; laciniae divided for about 74 (69–79)% of their total length. Presternal region transversely striate. Sternal shield with sparse anterolateral reticulations, bearing three pairs of setae (st1–st3) and two pairs of lyrifissures. Metasternal plate roundish, bearing the fourth pair of sternal seta (st4) and a pair of lyrifissures (iv4). Genital shield smooth in specimens collected from the United Arab Emirates, with slight reticulations in specimens collected from France, bearing genital setae (st5); paragenital lyrifissures (iv5) on unsclerotised cuticle, posterolateral to st5. Ventrianal shield subtriangular, reticulate, bearing six pairs of opisthogastric setae (JV1–JV4, ZV2, ZV3) in addition to the circum-anal setae, with two pairs of lyrifissures between ZV2 and ZV3 and a pair of marginal pores posterolateral to para-anal setae; anal opening small. Opisthogastric cuticle with a line between genital and ventrianal shields, and two pairs of metapodal plates, the anterior smaller than the posterior. Unsclerotised cuticle around ventrianal shield with four pairs of lyrifissures and seta JV5. Exopodal plate distinct from anterior margin of coxa II to posterior margin of coxa IV.
Peritrematic plate and peritreme (Fig. 72): peritrematic plate fused with dorsal shield at level of j2 and broadly fused with exopodal plate beside coxa IV; with a lyrifissure and a pore in region between coxae II–III (ip1, gp2), two lyrifissures and a pore behind stigma (ip2, ip3, gp2), and with a pore near posterior end [SJ, inguinal solenostome of Athias-Henriot, 1969, gv2 of Lindquist & Moraza, 2009]; peritreme extending forward to region between j2 setae.
Spermatheca (Fig. 73): spermathecal structure complex, distinct in specimens from the United Arab Emirates (not in specimens from France), apparently with a large rounded atrium followed by a short, lightly sclerotised calyx; major duct wide and minor duct apparently corresponding to a duct with rough wall.
Gnathosoma (Figs 74–76): general shape of chelicera as for the new characterisation of the phytoseioides group; fixed digit bearing 12 (10–13) teeth in addition to apical tooth; movable digit, bearing three teeth in addition to the apical tooth. Anteromedian region of epistome convex and denticulate. Deutosternum with seven transverse lines of denticles; first (distal) to fifth with 8–9 denticles each; sixth with 15–16 denticles and seventh with 11–12 denticles.
Legs (Fig. 77): leg pretarsi I–IV each with a pair of claws and pulvillus with three rounded lobules. Leg IV with three macrosetae on genu (ad2), basitarsus (pd3) and telotarsus (pd2), all smooth. Leg chaetotaxy (trochanter to tibia): I: 1, 0/1, 1/2, 1; 2, 3/2, 2/1, 2; 2, 3/2, 3/1, 2; 2, 3/2, 3/1, 2; II: 1, 0/1, 0/2, 1; 2, 3/1, 2/2, 1; 2, 3/1, 2/1, 2; 2, 2/1, 2/1, 2; III: 1, 1/1, 1/1, 0; 1, 2/1, 1/0, 1; 2, 2/1, 2/1, 1; 2, 1/1, 2/1, 1; IV: 1, 1/1, 0/1, 1; 1, 2/1, 1/0, 1; 2, 2/1, 3/0, 1; 2, 1/1, 3/1, 2.
Remarks. Specimens from France are considerably larger than specimens from the United Arab Emirates; all measurements of structures of French specimens were consistently larger. Seta s6 was not shown in the original description of the species. The difference between the description of the spermathecal apparatus given by Walter & Lindquist (1989), apparently based on specimens from Colorado, USA, and the description given in this paper is Table 3. Mean (minimum – maximum) measurements in µm of characters of type specimen and female specimens identified as
asioseius youcefi Athias-Henriot from two geographic regions.
Character1 Holotype 2 United Arab France Character1 Holotype 2 United Arab France
Emirates Emirates
DS L 445-490 374 (353–403) 429 (408–440) SS L 70-80 81 (79–85) 84 (80–86) DS W 245 222 (205–240) 293 (270–315) SS W 81 84 (79–90) 98 (96–100)
35-40 30 (26–33) 37 (34–40) GS L 69-73 110 (103–121) 136 (132–140)
GS W at post.
31 (28–34) 37 (35–41) 93-97 81 (75–90) 93 (90–96)
corners
30 (27–34) 36 (35–37) st5–st5 59 (56–60) 71 (65–75)
24 (22–25) 29 (28–30) Anus length 22 (21–23) 23 (22–25)
32 (30–34) 37 (36–39) st 1 20-30 25 (23–27) 34 (32–35) 2 28 (24–30) 36 (34–37) st 2 20-30 24 (23–26) 29 (27–30) 4 23 (21–26) 31 (31–32) st 3 20-30 23 (22–25) 29 (26–30) 5 15 (13–16) 14 (12–15) st 4 20-30 26 (24–28) 29 (28–30) 2 27 (25–30) 35 (33–36) st 5 20-30 24 (22–25) 23 (22–26) 4 33 (28–36) 42 (41–43) Jv 1 20-30 21 (20–21) 25 (23–26) 5 34 (31–37) 40 (39–42) Jv 2 20-30 23 (22–24) 28 (28–29) 1 36 (35–38) 48 (46–50) Jv 3 20-30 24 (23–26) 33 (31–34) 3 55-60 48 (43–57) 65 (62–66) Jv4 35-40 25 (24–27) 35 (34–36) 4 55-60 45 (43–48) 67 (62–69) Jv5 65 41 (40–44) 59 (56–60) 5 80 54 (50–61) 75 (70–78) Zv 2 20-30 22 (21–23) 25 (24–26) 4 30 (25–35) 44 (43–46) Zv 3 20-30 20 (18–23) 21 (20–22)
... continued on the next page: length; W: width; shields: DS—dorsal, GS—genital, SS—sternal, VAS—ventrianal: ventrianal shield; NT: number of teeth; FD: fixed cheliceral digit; MD: movable cheliceral digit; 2from original description (Athias-Henriot, 1959)
seemingly due to the position of the spermathecae in the different specimens. Apparently, what they referred to as "smaller doughnut" and bead-like accessory structure may correspond to what are here interpreted respectively as lightly sclerotised calyx and minor duct.
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 28-33, DOI: 10.11646/zootaxa.3980.1.1, http://zenodo.org/record/288988