Myrmozercon iranicus Babaeian and Nemati, 2014

Babaeian, E., Seraj, A. A. & Nemati, A., 2014, Description Of A New Ant-Associated Species (Acari: Mesostigmata: Laelapidae) From Iran, Acarologia 54 (2), pp. 221-228 : 222-226

Myrmozercon iranicus Babaeian and Nemati n.sp.

Specimens examined — Holotype and two paratype females, Iran, Yazd, Taft, 31°45’ N 54°14’ E, 25 Nov. 2013, O. Joharchi coll., in nest of Messor sp .. Paratypes, two females, Shahrekord County, Dotu region , 30 June 2010, E. Babaeian coll., in nest of Messor sp ..

Diagnosis — Melittiphinae laelapid mites. Dorsal shield broad, not covering dorsal idiosoma, with 39 pairs of relatively long and barbed setae (excluding short and smooth setae z1): j1-j6, J1-J5, z1-z6, Z1- Z5, s1-s6, S1-S5, Zx2-Zx3, r2-r5. Two unpaired setae Jx present between J2-J4; epigynal shield posteriorly tapered. Post-stigmatal section of the peritrematal shield very elongate and extending well posterior to coxa IV to level of long metapodal shield.

Legs — Genu I and tibia I has three ventral setae, femur IV and genu IV with six and nine setae, respectively.

Description — Female (4 specimens). ( Figures 1 and 2 )

Dorsal idiosoma ( Figure 1A ) — Dorsal shield 464 – 482 long, 258 – 278 wide at level of r3, with reticulate pattern on the whole surface except median region, rounded posteriorly and does not completely cover idiosoma, with complement of 39 pairs of setae and two unpaired setae. Podonotal area of shield with 22 pairs (j1-j6, z1-z6, s1-s6, r2-r5) and opisthonotal area with 17 pairs (J1-J5, Z1-Z5, S1- S5, Zx2, Zx3), and two unpaired postero-median setae (Jx) between setae J2-J4; all setae (except z1) slightly thickened, distinctly barbed in apical third, and usually long enough to pass the base of the setae next behind, seta z1 10 – 12 shortest and smooth. Length of setae: j1 30 – 32, s1, j2 22 – 25, j3, s2 35 – 37, z2, s3, r2 40 – 42, j4, z3, r3, s4, S1 47 – 50, z4, r4, r5, S2, J5 52 – 54, j5, z6, s5, s6 58 – 60, J1, J2, Z4, Z5, S3,

Leg IV, right side; E – Coxa and trochanter IV, right side. Scale bare= 100 µm

S4, S5 62 – 64, J3, J4, Z1, Z2, Zx2, Zx3 65 – 67. Dorsal shield with complement of 20 discernible pore-like structures (7 podonotal, 13 opisthonotal), of which 7 (4 podonothal, 3 opisthonotal) appear secretory (gland pores) and 13 (3 podonotal, 10 opisthonotal) non-secretory (lyrifissures). Dorsal shield with smooth even edge.

Ventral idiosoma ( Figure 1B ) — Tritosternal base 33 long with two free pilose laciniae 46 long. Presternal platelets absent. Sternal shield 83-85 long and 106 – 112 wide, finely lineate-reticulate anterolaterally, continuous with endopodal platelets between coxae I-II and II-III, anterior margin undulate, posterior margin strongly concave, bearing setae st1-st3 smooth, thin and 39 – 44 long, and two pairs of lyrifissures (iv1-iv2), oriented angular. Metasternal setae st4 31 – 35 long and third pair of sternal lyrifissures (iv3) inserted on soft cuticle. Endopodal platelets between coxae III-IV narrow and anteriorly separate from sternal shield, and with small exopodal plates between coxae II-III. Epigynal shield 223 – 234 long and 88-91 wide, with conspicuous reticulation, with hyaline anterior margin, shield slightly inflated behind st5 and tapered posteriorly. Paragenital lyrifissures (iv5) located on unsclerotised cuticle lateral to epigynal shield. Inguinal area with a pair of elongate and narrow metapodal plates, 70 – 75 long and 4 – 6 wide and a pair of small platelets; a pair of small paragenital platelets also present. Opisthogastric integument with 10 pairs of setae and five pairs of lyrifissures: Jv1 35 – 40, Jv2 40 – 42, Jv3 42 – 45, Jv4 52 – 55, Jv5 59 – 62, Zv1 32 – 42, Zv2 35 – 40, Zv3 40 – 42, Zv4 47 – 50, Zv5 57, each seta arising on a small platelet, Zv1 and Jv1 smooth, remaining setae barbed distally. Podal shields present with gv2 gland pore. Anal shield sub-triangualr and slightly concave anteriorly, 69 – 72 long and 56 – 58 wide, with faint striations in pre-anal region, post-anal seta 26 – 29 long, thicker and longer than para-anal setae 23 – 25, adanal gland pores gv3 on lateral edges of the shield above para-anal setae, cribrum narrow and inserted on posterior margin. Peritremes 245 – 250 long, elongate and extending from stigmata at mid level of coxae III-IV to the posterior margin of coxa I, peritrematal shields with one pair of gland pores at mid-level of coxa III, and one pair of lyrifissures near anterior level of coxa III, post-stigmatal section of peritrematal shield elongated, bearing lyrifissure ip and gland pore gp3.

Gnathosoma ( Figures 1 C-G) — Epistome subtriangular with smooth margin ( Figure 1D ). Subcapitulum ( Figure 1C ): Hypostomal (h1, h2, h3) and capitular setae (pc) simple and smooth, 17 – 20, 19 – 21, 34 – 37 and 44 – 46 long, respectively. Deutosternal groove has six transverse rows of fine denticles (from anterior to posterior) 15-12-13-15- 12-9 denticles in each row, respectively, in deutosternal groove of one paratype there are seven transverse rows of denticles; internal malae abutting and pointed apically, finely fringedlaterally; labrum with pilose surface, extending to mid-level of palp-femur. Corniculi 16 – 18 long, weakly sclerotised, and flanked by a pair of thin salivary styli. Palps 83-87 long, with smooth setae, chaetotaxy of palps from trochanter to tarsus: 2-5-6-14-15, v2 on trochanter thickened, al1 on femur thickened and with narrowly rounded tip, palp-genu with seta al1 rod-like and seta al2 thickened and similar to al1 on the femur, dorsal setae on femur, genu and tibia thickened, tarsus with simple and thickened setae ( Figure 1E ). Palp-tarsal apotele two-tined, basal tine slightly shorter ( Figure 1F ). Chelicerae ( Figure 1G ) with movable digit edentate, 19 – 21 long, fixed digit edentate, 11 – 12 long, with fringed hyaline arthrodial process at the base of the movable digit, middle segment 54 long, dorsal seta short.

Legs ( Figures 2 A-E) — Length of leg I 308 – 366, leg II 237 – 260, leg III 237 – 257, leg IV 324 – 386. Chaetotaxy (left and right sides of legs in all specimens were examined): Leg I: coxa 0 0/1 0/1 0, trochanter 1 0/2 1/1 1 (pd thickened, al slightly thickened), femur 2 3/2 2/2 2 (al1 slightly thickened, al2 short and simple), genu 2 3/2 3/1 2 (ventral setae slightly thickened), tibia 2 3/2 3/1 2 (ventral setae slightly thickened) ( Figure 2A ). Leg II: coxa 0 0/1 0/1 0, trochanter 1 0/1 0/2 1 (al and pl slightly thickened), femur 1 3/2 2/1 1 (ad 1 thickened, pd1 and pd2 slightly thickened), genu 2 3/1 2/1 2 (ventral setae slightly thickened), tibia 2 2/1 2/1 2 (ventral setae slightly thickened) ( Figure 2B ). Leg III: coxa 0 0/1 0/1 0 (av long), trochanter 1 0/1 0/2 1 (al thickened), femur 1 2/0 1/1 1 (ad1 thickened, pv tiny thickened), genu 2 2/1 2/1 1 (av and pv slightly thickened), tibia 2 1/1 2/1 1 (av and pv slightly thickened) ( Figure 2C ). Leg IV: coxa 0 0/1 0/0 0, trochanter 1 0/1 0/2 1 (al thickened)( Figure 2E ), femur 1 2/1 1/0 1 (ad1 thickened), genu 2 2/1 3/0 1 (av slightly thickened), tibia 2 1/1 3/1 2 (av and pv slightly thickened) ( Figure 2D ). Other setae are fine and needle like. Tarsi II-IV with 18 setae 3 3/2 3/2 3 + mv, md. All legs with two tiny claws and a rounded membranous pulvillus.

Etymology — The name " iranicus " is referred to the country of origin ( Iran) where the type specimens were collected.

Notes — According to the key to species of Myrmozercon occurring in the Palaearctic Region presented by Joharchi and Moradi (2013), M. iranicus Babaeian and Nemati n. sp., keys out to Myrmozercon michaeli Joharchi, 2013 (dorsal shield hypotrichous and truncated, peritreme long, metasternal setae st4 present and almost all dorsal setae barbed in apical end).

It is interesting to note that these two species of Myrmozercon were collected in the nest of an unidentified species of Messor , and in nearly similar geographical locations.

The two species are very similar, the only obvious differential characters being the body size (Idiosoma length × width of five female M. iranicus Babaeian and Nemati n. sp. c. 450 – 488 × 337 – 348, while those of eight M. michaeli c. 560 – 580 × 372 – 446), the shape of idiosoma (broad in M. iranicus Babaeian and Nemati n. sp., but oval in M. michaeli ), length of peritreme (longer and reaching to posterior margin of coxa I in M. iranicus Babaeian and Nemati n. sp., but shorter and reaching to mid-level of coxa II only in M. michaeli ), the shape of the epigynal shield (cone-shaped, posteriorly pointed in M. iranicus Babaeian and Nemati n. sp., but nearly tongue-shaped, with rounded posterior margin in M. michaeli ), post-stigmatal section of peritrematal shield (elongate, extending well behind exopodal shield and reaching to metapodal shield in M. iranicus Babaeian and Nemati n. sp., but shorter and not reaching to posterior margin of coxa IV in M. michaeli ), number of unpaired setae (Jx) on the dorsal shield (two in M. iranicus Babaeian and Nemati n. sp., but zero in M. michaeli ), chaetotaxy of trochanter I, femur II, III and genu IV (1 0/2 1/1 1,1 3/2 2/1 1, 1 2/0 1/1 1 and 2 2 / 1 3 / 0 1 in M. iranicus Babaeian and Nemati n. sp., but 1 1/2 0/1 1, 2 3/1 2/2 1, 1 2/1 1/0 1 and 2 2/1 3/0 2 in M. michaeli , respectively), seta pd1 on femur II (slightly thickened in M. iranicus Babaeian and Nemati n. sp., but thickened in M. michaeli ) and setae pl and pd on trochanter I (pd thickened in M. iranicus Babaeian and Nemati n. sp., but pl thickened in M. michaeli ). Characteristic ornamentation including Λ- shaped lines and polygonal cells on the epigynal shield of the two species is also different ( Joharchi and Moradi, 2013).

Figures

FIGURE 1: Myrmozercon iranicus Babaeian and Nemati n. sp., female: A – Dorsal idiosoma; B – Ventral idiosoma; C – Gnathosoma; D – Epistome; E – Palp, right side (trochanter, femur and genu); F – Palp-tarsal apotele; G – Chelicera.

FIGURE 2: Myrmozercon iranicus Babaeian and Nemati n. sp., female: A – Leg I, right side; B – Leg II, left side; C – Leg III, right side; D –