Hypoaspis larvicolus, Joharchi, Omid & Halliday, Bruce, 2011

Joharchi, Omid & Halliday, Bruce, 2011, New species and new records of mites of the family Laelapidae (Acari: Mesostigmata) associated with Coleoptera in Iran, Zootaxa 2883, pp. 23-38 : 27-31

Hypoaspis larvicolus sp. nov.

Specimens examined. Holotype, female, Iran, Karaj, 35°48' N, 50°59' E, alt 1384 m, 10 June 2008, O. Joharchi coll., on larva of Polyphylla sp. (in JAZM). Paratypes: five females, two males, same data as holotype (in JAZM and ANIC).

Description. Female. Dorsal idiosoma. Dorsal shield oval shaped, length 956–1008 µm, width at level of r3 516–525 µm (n = 4), with weak posterolateral reticulation ( Fig. 10 ). Shield with 38 pairs of long setae, 21 pairs of podonotal setae on shield, plus s6 and r6 outside shield, and 17 pairs of opisthonotal setae on shield, including two pairs of Zx setae between J and Z setae; Z4 longest (310–365 µm), s4 (194–231 µm), r4 (252–260 µm), j3 (252– 273 µm) also long, j4 long enough to reach z5, j6 long enough to reach past J1 but not long enough to reach to J2, J1 long enough to reach Zx1 but not long enough to reach J3, J4 long enough to reach J5. Soft skin surrounding shield with nine pairs of setae.

Ventral idiosoma ( Fig. 11 ). Tritosternum with paired pilose laciniae, pre-sternal area weakly sclerotised. Sternal shield with straight anterior margin and slightly concave posterior margin, with three pairs of smooth sternal setae, one pair of lyrifissures adjacent to setae st1, and a pair of circular pores between st2 and st3, surface of sternal shield with distinct polygonal ornamentation throughout. Metasternal platelets absent, metasternal setae st4 and metasternal pores located on small circular or elongate platelets in soft skin, some specimens with one or both pores on posterior edge of sternal shield ( Figs 21–23 ). Endopodal plates II/III completely fused to sternal shield, endopodal plates III/IV elongate, narrow, curved. Genital shield tongue-shaped, length 327–336 µm, maximum width 155–147 µm, posterior margin rounded, surface with polygonal ornamentation, bearing the genital setae st5. Paragenital pores located on soft skin close to st5. Anal shield triangular, its anterior half with lineate ornamentation, para-anal setae longer than unpaired post-anal seta, cribrum large, anal pores variable in position, located either on edge of anal shield or on minute platelets outside anal shield. Opisthogastric soft skin with one pair of oval metapodal plates and 11 pairs of smooth setae, ZV5 and JV5 very long and wavy. Exopodal plates behind coxa IV small and narrow. Peritrematal shield free, peritreme extending from coxa IV to mid level of coxa I, post-stigmatal section conspicuous and narrow, with two pairs of post-stigmatal pores, and one pair of pores anterior to the stigmata.

Gnathosoma . Epistome irregularly denticulate laterally, central margin smooth with apical point ( Fig. 12 ). Hypostomal groove with six rows of denticles, each row with about ten small teeth, and smooth anterior transverse line. Hypostome with four pairs of setae, internal posterior hypostomal setae h3 longest ( Fig. 13 ). Corniculi robust and horn-like, reaching mid-level of palp femur. Palp chaetotaxy: trochanter 2, femur 5, genu 6, tibia 12, tarsus 15, genu with a distinct dorso-distal triangular condyle, all setae smooth and needle-like, palp tarsal claw two-tined. Fixed digit of chelicera with a small triangular proximal tooth, about ten small teeth, a larger median tooth, and one large distal tooth ( Fig. 14 ), pilus dentilis short and robust, dorsal seta short, thick, prostrate, movable digit with two large teeth, arthrodial membrane with a rounded flap and a few short filaments.

Legs. Legs II and III short, leg IV longest. Chaetotaxy: Leg I: coxa 0 0/1 0/1 0, trochanter 1 0/1 1/2 1, femur 2 3/1 2/3 2, genu 2 3/2 3/1 2, tibia 2 3/2 3/1 2. Leg II: coxa 0 0/1 0/1 0, trochanter 1 0/1 0/2 1, femur 2 3/1 2/2 1 (macroseta pd 1 252–284 µm, Fig. 15 ), genu 2 3/1 2/1 2 (pd 1 and pd 2 longest), tibia 2 2/1 2/1 2. Leg III: coxa 0 0/1 0/1 0, trochanter 1 1/1 1/1 0, femur 1 2/1 1/0 1 (macroseta ad 1 281–298 µm, Fig. 16 ), genu 2 2/1 2/1 1 (ad 1 long 147– 178 µm, pd 1 long 165–172 µm, ventral setae all thick, Fig. 17 ), tibia: 2 1/1 2/1 1 (pl and ventral setae thick). Leg IV: coxa 0 0/1 0/0 0, trochanter 1 1/1 0/1 1, femur 1 2/1 1/0 1 (macrosetae ad 1 370–400 µm, ad 2 134–144 µm, Fig. 18 ), genu 2 2/1 3/0 1 (macrosetae ad 1 275–290 µm, pd 1 253–268 µm, av thick, Fig. 19 ), tibia 2 2/1 3/1 2 (pl 1 and ventral setae thick). Tarsi I–IV with 18 setae 3 3/2 3/2 3 + mv, md. On tarsus II, al 1, pl 1 and all ventral setae thick. On tarsus IV macrosetae ad 2 (218–222 µm), pd 2 (228–243 µm), ad 3 (240–253 µm), pd 3 (240–260 µm) ( Fig. 20 ). All pre-tarsi with a pair of claws and a long thin membranous ambulacrum.

Insemination structures. Insemination ducts opening on posterior margin of coxa III; sacculus indistinct, apparently unsclerotised.

Male. Dorsal idiosoma. Dorsal shield length 740–810 µm, width at level of r3 441–462 µm (n = 2) structure and chaetotaxy as for female.

Ventral idiosoma ( Fig. 25 ). Sternal, genital, endopodal and ventral shields fused to form a strongly ornamented composite shield with nine to ten pairs of setae and five pairs of pores, posterior margin of this shield concave and irregular, with unpaired setae in both specimens. Anal shield free, triangular, its anterior half with lineate ornamentation, para-anal setae longer than unpaired post-anal seta, cribrum large, anal pores either on edge of shield or in adjacent soft skin.

Gnathosoma ( Figs 24 , 26 ). Movable digit of chelicera with one large tooth, spermatodactyl long slender, more than double length of movable digit, with truncate tip and an apparently unsclerotised ventral section near its base, fixed digit with one large distal tooth and minute pilus dentilis.

Legs. Chaetotaxy as in female, leg II with several stout pointed spine-like setae on ventral surface of femur ( Fig. 27 ), genu ( Fig. 28 ), tibia ( Fig. 29 ) and tarsus, av 1 on femur II very stout, leg III with one macroseta on femur ( Fig. 30 ) and two macrosetae on genu ( Fig. 31 ).

Etymology. The name of this species refers to the fact that the specimens were found on the larva of Polyphylla sp. and not the adult.

Notes. Hypoaspis larvicolus differs from almost all other species in the genus by its long dorsal setae and the presence of four long macrosetae on tarsus IV, as well as the two macrosetae on genu III and IV, and 11 setae on tibia IV instead of the usual 10. The male is distinctive in having a separate anal shield, which in other species is fused to the sternal-genital-ventral shield.

Figures

FIGURES 10 – 20. Hypoaspis larvicolus sp. nov., female. 10. Dorsal idiosoma; 11. Ventral idiosoma; 12. Epistome; 13. Hypostome; 14. Chelicera; 15. Femur II; 16. Femur III; 17. Genu III; 18. Femur IV; 19. Genu IV; 20. Tarsus IV. Scale bar = 100 μm for 10, 11, 15 – 20, 50 μm for 12 – 14.

FIGURES 21 – 24. Hypoaspis larvicolus sp. nov. 21. female, sternal shield with both metasternal pores on sternal shield; 22. female, sternal shield with one metasternal pore on sternal shield and one off shield; 23, female, sternal shield with both metasternal pores on separate elongate platelets; 24. male, chelicera, unsclerotised section of spermatodactyl arrowed. Scale bar = 100 μm for figures 21 – 24.

FIGURES 25 – 31. Hypoaspis larvicolus sp. nov., male. 25. Ventral idiosoma; 26. Chelicera; 27; femur II; 28. Genu II; 29. Tibia II; 30. Femur III; 31. Genu III. Scale bar = 100 μm for 25, 27 – 31, 50 μm for 26.