Ameroseius eumorphus Bregetova, 1977

Khalili-Moghadam, A. & Saboori, A., 2016, Redescription of Ameroseius eumorphus Bregetova (Acari: Mesostigmata: Ameroseiidae), a new record of Epicriopsis Berlese from Iran and a new homonym in Ameroseiidae, Acarologia 56 (4), pp. 537-551 : 538-546

Ameroseius eumorphus Bregetova, 1977

( Figures 1-3 )

A. eumorphus Bregetova, 1977: 153 .

A. eumorphus - Narita et al. 2013: 7.

Diagnosis — Palp tarsal claws and corniculi two and three tined respectively; setae h1 about twice thicker than h2 and h3; fixed cheliceral digit with four large teeth near the base of digit and subapical offset gabelzahn. Dorsal shield with 28 pairs of lanceolate setae and very slightly serrate (j1 leafshaped), tips of J2 and J4 do not reach the base of J4 and Z5, respectively. Opisthogasteric region with 6 pairs of setae, 2 of which on the ventri-anal shield (in addition to circumanal setae). Ventri-anal shield wider than long, anterior margin with clearly depression, pre-anal setae (Jv2) set closed together.

Adult female ( Figures 1-3 ) (5 specimens measured)

Gnathosoma ( Figure 1A ) — Hypostomal and palpcoxal setae smooth; h1 26 (26-27), h2 21 (20- 22), h3 18 (16-19) and pc 24 (22-26). Deutosternal groove narrow; transverse rows of denticles not discernable on any of the specimens examined. Corniculi trifid. Epistome arc-shaped with an elongate, acute and smooth central projection ( Figure 1B ). Chelicera with dorsal seta and dorsal lyrifissure, fixed cheliceral digit 24 (22-26) long, with four large teeth near the base of digit and subapical offset gabelzahn, setaceous pilus dentilis not observed, movable digit 22 (22-24) long and with 2 small subapical teeth, middle cheliceral segment 53 (50-56) long ( Figure 1C ). Palpus 72 (66-79) long; number of setae from trochanter to tibia: 2, 5, 6, and 14. Palp apotele bifid ( Figure 1D ).

Dorsal idiosoma ( Figure 2 ) — Dorsal shield entire, totally reticulate; reticula formed by simple lines; 360 (338 – 400) long (from its anteromedian edge anterior to bases of setae j1 to its posteromedian edge posterior to bases of setae Z5) and 235 (218 – 255) wide at level of s6; with 28 pairs of setae, 18 pairs on podonotal region (j1-6, z2, z4-5, s1-2, s4- 6, r2-5) and 10 pairs on opisthonotal region (J2, J4, Z1-2, Z4-5, S2-5); dorsal setae lanceolate and very slightly serrate, j1 leaf-shaped, serrate on both sides and slightly thicker than the other dorsal setae ( Figure 2 ). Lengths of dorsal setae: j1 24 (23-25); j2 30 (29-31); j3 32 (31-34); j4 37 (36-38); j5 45 (43-46); j6 59 (52-64); J2 68 (67-71); J4 72 (69-76); z2 36 (35-37); z4 36 (34-37); z5 47 (44-50); Z1 43 (41-46); Z2 43 (45- 53); Z4 59 (54-64); Z5 51 (52-53); s1 23 (22-24); s2 33 (31-36); s4 39 (34-42); s5 43 (42-44); s6 42 (42-43); S2 41 (40-42); S3 38 (37-40); S4 42 (38-45); S5 43 (42-43); r2 32 (32-34); r3 28 (27-30); r4 34 (33-35); r5 33 (31- 34). A few setae reach the bases of the subsequent setae of each series but tips of J2 and J4 do not reach the base of J4 and Z5, respectively. Pore-like structures on podonotal and opisthonotal regions were not clear and not observed.

Ventral idiosoma ( Figure 3 ) — Tritosternum 73 (67-75) with columnar base 25 (24-26) and pilose laciniae 43 (40-44) which are fused along basal part for 18 (17-19). Sternal shield reticulate; 74 (71-79) long along midline from anterior edge to its posterior margin and 68 (66-73) wide at widest level, bearing two pairs of setae: st1 23 (22-24) and st2 22 (20-23) and two pairs of lyrifissures (iv1, iv2). Setae st3 21 (19-23) located on two small plates adjacent to posterior margin of sternal shield and st4 19 (15-21) on unsclerotized cuticle. Third pair of lyrifissures (iv3) located on posterior edge of metasternal plates. Genital shield reticulate, 78 (77-84) long at midline and 89 (86-91) wide at widest area, truncate posteriorly, bearing genital setae st5 20 (17-22); a pair of pores on soft cuticle postero-laterad of st5. Ventri-anal shield reticulate, wider than long, anterior margin with clearly depression, and a pair of pre-anal setae (Jv2) set closed together, 113 (107- 111) long at midline from the anterior margin to the posterior edge of the cribrum and 131 (127- 144) wide at the widest part, bearing 2 pair of setae, Jv2 21 (18-22) and Jv3 21 (18- 23) in addition to para-anal setae 19 (18-21) and post-anal seta 27 (26-28); unsclerotized cuticle of opisthogasteric region with setae Jv1 19 (15-22), Jv5 63 (58-66), Zv1 18 (16-19) and Zv2 15 (14-16), 4 pairs of lyrifissures, a pair of elongate metapodal platelets with minute platelets located at posterior margin, membranous layer and remnants platelets are between genital and ventrianal shield. All ventral setae setiform and smooth, Jv5 leaf-shaped similar to dorsal setae and post-anal seta serrate. Remnants of endopodal shield represented by a triangular platelets between coxae I and II, II and III, and stretched, curved triangular platelet between coxae III and IV. Remnants of exodopodal shield represented by a triangular platelets between coxae I-II and coxae II-III. Peritreme almost reaching level of setae j2. Peritrematal shield wide, with 5 pore-like structures and lyrifissures on exterior lateral margin: 1 lyrifissure between coxae I-II, 1 pore-like structure at level of anterior margin of coxa II, 1 large pore at level of anterior margin of coxa III, 1 pore-like structure located at posterior side of stigmatal opening and 1 lyrifissure near the tip of the shield posterior to coxa IV. A minute platelet present beneath of arched poststigmatal plate.

Legs ( Figure 4 ) — Tarsi of all legs with pulvilli and claws. The chaetotaxy and measurements of all leg segments are as follows:

leg I ( Figure 4A ), 347 (348-352), coxa 50 (52-55) 0 0/1 0/1 0, trochanter 27 (25-29) 1 0/1 1/2 1, basifemur 15 (14-16), telofemur 40 (36-44) 2 3/1 2/2 2, genu 45 (43-47) 2 3/2 2/1 2, tibia 44 (43-45) 2 3/2 2/1 2, tarsus (with stalk and pretarsus) 115 (113-120);

leg II ( Figure 4B ), 269 (248-290), coxa 24 (23-26) 0 0/1 0/1 0 (pv seta tick and barbed) trochanter 26 (25-27): 1 0/1 0/2 1, basifemur 14 (13-15), telofemur 41 (32-47) 2 2/1 2/2 1, genu 34 (32-36) 2 3/1 2/1 2, tibia 30 (29-31) 2 2/1 2/1 2, tarsus (with stalk and pretarsus) 93 (83-103);

leg III ( Figure 4C ), 267 (255-275), coxa 26 (24-27) 0 0/1 0/1 0, trochanter 29 (28-31) 1 0/1 0/2 1, basifemur 13 (14-16), telofemur 32 (27-36) 1 2/1 1/0 1, genu 31 (29-32) 2 2/1 2/1 2, tibia 30 (28-32) 2 1/1 2/1 2, tarsus (with stalk and pretarsus) 91 (84-97); leg IV ( Figure 4D ), 341 (328-354), coxa 27 (21-29) 0 0/1 0/0 0, trochanter 33 (28-38) 1 0/1 0/2 1, basifemur 17 (16-18), telofemur 47 (45-51) 1 2/1 1/0 1, genu 45 (43-47) 2 2/1 2/1 2, tibia 44 (41-46) 2 2/1 2/1 2, tarsus (with stalk and pretarsus) 121 (113- 127). Tarsi I-IV with 18 setae 3 3/2 3/2 3 + mv, md. Legs I and IV longer than legs II and III.

Material examined — Specimens were collected at the following places, habitats, numbers and dates: Chaharmahal Va Bakhtiari Province, Shahrekrod city (32°14’32" N, 50°50’26" E, 2039 m a.s.l.), soil, 4 females, coll. A. Khalili-Moghadam, 20 July 2013 ; Lordegan city (31°31’11" N, 50°37’51" E, 1482 m a.s.l.), litter, 6 females, coll. A. Khalili- Moghadam, 28 March 2014 ; Khuzestan Province, Ahvaz city (indeterminate), soil, 1 female, coll. A. Nemati, 5 July 1998 ; Ahvaz city (31°18’84" N, 48°39’89" E, 17 m a.s.l.), soil of ant nest, 4 females, coll. F. Vatankhah, 6 March 2014 .

Remarks — According to Evans 1963 (p. 300) adult female of Ameroseiidae have 9 setae on tibia IV: 2-2/1-2/1-1. This is different from what was observed for Ameroseius potchefstroomensis ( Kruger and Loots, 1980) and A. mineiro Narita et al., 2013 (presence of pl2). According to our observations on 30 specimens of A. eumorphus , it revealed that this situation (the presence of pl2) also is correct for this species.

Narita et al. (2013) considered plumosus speciesgroup includes 8 species. This species group has the following features: dorsal shield reticulate and without pit-like depressions; with 28 pairs of setae, exceptionally 26 pairs (for Ameroseius dipankari Bhattacharyya, 2004 ); dorsal setae are lanceolate to leaf-shaped, also opisthogastric region with 5-6 pairs of setae, which 2 pairs are located on ventrianal shield.

One species of this group is A. eumorphus which is similar to Ameroseius mineiro , A. wahabi ( Ibrahim and Abdel-Samed, 1999) , A. parplumosus ( Nasr and Abou-Awad, 1986) , A. potchefstroomensis , A. plumosus ( Oudemans, 1902) and A. pseudoplumosus Rack, 1972 . To compare A. eumorphus with similar species, several important taxonomic characters were considered and comparison between them is shown in Table 1.

Distribution, habitat and host of A. eumorphus — The distribution, habitat and host of A. eumorphus are presented in Table 2.

Type deposition — Collection of the Zoological Institute of the Academy of Sciences of the USSR, Leningrad .

Figures

FIGURE 1: Ameroseius eumorphus Bregetova, 1997 (female): A – Hypostome, B – epistome, C – Chelicera, D – apotele.

FIGURE 2: Ameroseius eumorphus Bregetova, 1997 (female): A – dorsal shield, B – j1, C – dorsal setae.

FIGURE 3: Ventral idiosoma of Ameroseius eumorphus Bregetova, 1997 (female).

FIGURE 4: Ameroseius eumorphus Bregetova, 1997 (female): A – Leg I, B – Leg II, C – Leg III, D – Leg IV.