Hypoaceus pycnosis ( Karg, 1979 )

Nemati, Alireza, Gwiazdowicz, Dariusz J. & Riahi, Elham, 2021, A new genus of Laelapidae (Acari: Mesostigmata) from South America, Persian Journal of Acarology 10 (2), pp. 167-189 : 179-183

Hypoaceus pycnosis ( Karg, 1979) ( Figs. 7–11 )

Hypoaspis ( Alloparasitus) pycnosis Karg, 1979: 77 .

Hypoaspis ( Alloparasitus) pycnosis – Karg 1982: 237; Karg 1989: 119; Nemati and Gwiazdowicz 2016: 43.

Hypoaspis ( Alloparasitus) pygnosis (sic). – Huhta and Karg 2010: 328.

Alloparasitus pycnosis – Casanueva 1993: 157.

Laelaspis pycnosis – Freira 2007: 213.

The most taxonomic names mentioned above, have been cited in Moreira, 2014.

Specimen examined

Hypoaspis pycnosis Karg, 1979 ; Chel. Nm. 4080; ZMB Kat. Nr. 41150; Paratypus Argentinien, Rio Negro, El Bolson, Tal d. Rio Azul ; 340m. Laubstrcu in Libocedrus-Lomatia-Wald, 10.10.61.

Note

While the above-mentioned slide was the only one in Museum für Naturkunde Berlin but marked as a paratype. Moreira (2014) recorded the type depository of this species in Naturwissenschaftlichen Museum, Budapest, Hungary. On the other hand, Karg (1979) himself has mentioned some ranges for some of the traits measurements of this species in its original description, which probably indicates that this species has more than one slide.

Diagnosis

Setae Zx absent; dorsal setae not elongate (33–63); genitiventral shield well expanded posterior to coxae IV, reticulated at anterior part; epistome with fair denticles in anterior margin, supralabral process wider and similar to long style.

Description (Female)

Dorsal idiosoma ( Fig. 7A ) – Dorsal shield oval-shaped, 753 long, width at level of setae r3 556; avoid ornamentation throughout, shield with 38 pairs of thin and simple setae, 23 pairs on podonotal region including j1–6; z1–6; s1–6; r2–5 and one extra paired zx setae between z3-z4; and 15 pairs on opisthonotal part encompasses of J1–5, Z1–5, S1–5; setae Zx2–3 absent, the distance of J2-J2 is about twice of J1-J1 distance. Dorsal setae varies in length: in podonotal the setae z1 shortest (13), the others 37–63; in opisthonotal area 33–57. Cuticle between dorsal and ventral side of body bearing r6 at ventral side. Podonotal and opisthonotal regions with 11 pairs of discernable pore-like structures, as shown in Fig. 7A . It is worth mentioning that the dashed lines in Fig. 7A only indicate the location of the folded parts in the representative specimen on the slide. Obviously, the setae and the related discernible pore and pore-like structures have been displayed on the dorsal surface. An enlarged pore like structure (pustule-like in appearance) which probably accompanied by gd6 and is1 present at dorso-ventral side of opisthonotal near the setae Z1.

Ventral idiosoma ( Fig. 7B ) – Tritosternum bearing columnar base with 27 long, 12 wide at middle part and 28 basally, the laciniae was broken and not observed. Pre-sternal with a pair of slightly sclerotized plates with striae on surface. Sternal shield with reticulation except in posterior surface, 111 long, 168 wide at level of st2 and 286 at level of projection between coxae II-III, slightly concave at anterior margin and deeply at posterior. Sternal setae smooth, st1 (59), st2 (74) and st3 (83), the distances of st1-st1 (78), st2-st2 (123), st3-st3 (164), st1-st2 (59), st2-st3 (53); iv1–2 slitlike, located slightly behind st1 and between st2-st3 respectively. Metasternal setae absent; iv3 ovoid, located on postero-corner of sternal shield. Genitiventral shield well expanded posterior to coxae IV, extending to area adjacent to anterior margin of anal plate, reticulated at anterior surface, bearing several pore-like structures on the surface ( Fig. 8 ), with 368 long, 233 wide at level of st5, 360 at level of Zv 1 in widest part.

Genitiventral shield bearing three pairs of setae, including st5 (85), Zv1 (81) and Jv1 (66), the other setae on opisthogastric area consist of Zv2 (48) and Jv2–5 (35–47). Paragenital pores on podal plate surface at posterior part of coxae IV, five other pore-like structures observed on opisthogastric area. Anal shield not reticulate, with semi-circular anterior margin, 103 long, 172 wide (at widest part), paranal setae (47) longer than post-anal seta (27). Cribrum with prominent spicules, extending laterally almost to level of post-anal seta. Suboval metapodal plate observed at left side of genitiventral shield. Stigmata located at area between coxae III-IV, surrounded by almost wide stigmatal plate. Peritremes wide and long, extending to middle part of coxa I, separated from exopodal shield. Poststigmatal part extending nearly from anterior part of coxa IV to its posterior level. Exopodal and endopodal plates ( Fig. 9 ) similar to H. eugenitalis as explained above.

Gnathosoma – Hypostome ( Fig. 10 A ) with three pairs of setae; only h1 (48) could be observed in specimen examined (see a note under material examined). Palpcoxal setae smooth with 61 long. Deutosternal groove with six rows of 5–10 denticles, the anteriormost is smooth, first row of denticles arc medially. Corniculi normal, horn-like; internal malae consists of two toothed external appendages and two long and thread-like internal appendages. Epistome cup-like, rounded and fairly denticulate medially while smooth laterally ( Fig. 10 B ), with slender style underside. Labrum slender and slightly pubescent. Chelicerae ( Fig. 10 C ) arthrodial processes developed, moveable digit (89) with two teeth, middle article (157: from cheliceral dorsal seta to its posterior margin) ending in fixed digit (80), bearing a big tooth proximally behind setaceous pilus dentilis and three smaller teeth distally in addition to distal hook.

Palp ( Fig. 10D ) – Chaetotaxy normal (sensu Evans & Till 1965), with simple and thin setae, palp-tarsal claw two-tined, basal tine smaller (not in normal view in Fig. 10D probably due to preparation condition).

Legs – Tarsi I-IV with claws and ambulacra. Leg I 738 μm, coxa (93), trochanter (59), basifemur (36), telo-femur (120), genu (107), tibia (118), tarsus (205 μm); leg II 590 μm (excluding stalk and pretarsus), coxa (44), trochanter (87), femur (114), genu (102), tibia (90), basi-tarsus (29), telotarsus (124); leg III 497 μm (excluding stalk and pretarsus), coxa (51), trochanter (78), basi-femur (40), telo-femur (60), genu (65), tibia (64), basi-tarsus (22), telo-tarsus (117); leg IV 646 μm (excluding stalk and pretarsus), coxa (48), trochanter (87), basi-femur (36), telo-femur (89), genu (92), tibia (75), basi-tarsus (43), telo-tarsus (176). Legs I and IV longer than legs II and III. All leg setae smooth and pointed. Legs chaetotaxy is similar to genus condition. Leg I ( Fig. 11A ); leg II ( Fig. 11 B ): tarsus ( mv pointed and slightly thickened, av2 and pv2 thickened and spine-like, av1 and pv1 thickened and spur-like); leg III ( Fig. 11 C ): tarsus ( mv, av1-2, pv1-2 slightly thickened); leg IV ( Fig. 11 D ).

Insemination structures – Not seen.

Male Unknown.

Figures

Figure 7. Holotype female of Hypoaceus pycnosis (Karg, 1979) – A. Dorsal idiosoma; B. Ventral idiosoma. Scale bar: 100 µm.

Figure 8. Holotype female of Hypoaceus pycnosis (Karg, 1979) – Some of pore-like structures on the genitiventral shield surface.

Figure 9. Holotype female of Hypoaceus pycnosis (Karg, 1979) – Endo- and exopodal plates. Scale bar: 100 µm.

Figure 10. Holotype female of Hypoaceus pycnosis (Karg, 1979) – A. Hypostome; B. Epistome, labrum and supralabral process; C. Chelicera; D. Palp anterolateral view. Scale bar: 100 µm.

Figure 11. Holotype female of Hypoaceus pycnosis (Karg, 1979) – A. Right leg I, lateral view; B. Right leg II, lateral view; C. Right leg III, dorso-ventral view; D. Right leg IV, dorso-ventral view. Scale bar: 100 µm.