Fedrizzia abradoalves Seeman

Seeman, Owen D., 2007, Revision of the Fedrizziidae (Acari: Mesostigmata: Fedrizzioidea), Zootaxa 1480, pp. 1-55: 16-22

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http://doi.org/ 10.5281/zenodo.176844

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Fedrizzia abradoalves Seeman

sp. nov.

Fedrizzia abradoalves Seeman   sp. nov.

( Figs 22 – 26 View FIGURES 22 – 26 )

Type specimens: Holotype, F, 2 km E Sunday Ck, JSF, 16.iii. 1996, O. Seeman, ex Pharochilus dilatatus (Dalman)   ( S 73928 View Materials ). Paratypes, AUSTRALIA: Southeast Queensland: 3 F, 3 M, Duck Ck, LNP, 20.iii. 1995, D. E. Walter ( S 73998 View Materials -74003); F, M, Cherry Plain, BM, 12.ii. 1996, O. Seeman ( S 74004 View Materials - 5); 3 F, 3 M, Dandabah, BM, 12.ii. 1996, O. Seeman ( S 74006 View Materials - 11); 3 F, 5 M, 2 km E Sunday Ck, JSF, 16.iii. 1996, O. Seeman ( S 74015 View Materials - 19). All specimens collected from P. dilatatus   and deposited in QM. F, M, same data as holotype, deposited in ANIC.

Diagnosis. Both sexes: idiosoma   1020–1070 long, with 8–10 large pores; ventral shield with mesh-like pattern; marginal and ventrianal shields with lineate reticulations; anterolateral corner of ventrianal shield fused with ventral shield; exopodal patterning between CxII –III spotted; pedofossae III absent; CxIV-marginal suture absent; femur III and IV without lamellae, seta pv 1 not significantly thickened; femur IV elongated; seta h 1 unmodified. Female: setae st 2-4 7-9 long; lyrifissure stp 2 anterior of stp x; sternogynial shield with honeycomb-like reticulations, not flanked by a cluster of pores, and surrounded by a smooth area extending 109–130 posterior of genital shield. Male: sternoventral shield with suture behind genital opening demarking anterior smooth and posterior reticulated areas; genital opening not flanked by pores; seta h 3 positioned posterior of h 2.

Description. Female: Idiosoma   1020–1070 long, 750–780 wide, with 8–10 large pores (10–15 diameter) medially and posteriorly; anterior hyaline projection with 1 pair of barbed setae 55–68 long. Marginal setae 8– 13 long. Tritosternum base 35–40 long, 45–52 wide. Tetartosternum and sternal shield smooth; tetartosternum rectangular, 29–32 long at midline, 128–134 wide; st 1 smooth, 25–30 long; st 2-4 7–9 long; posterolateral margin of sternal shield acutely pointed, st 3-4 on posterior margin, eye-like pore stp x posterior stp 2. Sternogynial shield 131–145 long, 163–172 wide, with honeycomb-like reticulation. Sternogynial shield surrounded by smooth area that extends 109–130 posterior of sternogynial shield; remainder of ventral shield with meshlike pattern. Sternogynial shield flanked by 5 pairs of setae (5–10 long), smooth area surrounding sternogynial shield with 1 pair of setae medially. Ventral shield with a large pore (10–15 diameter) posteromedial of CxIV, 2 pairs of eye-like pores laterad of CxIV, ca. 15 pairs of small round pores, 10 pairs of setae, the most posterior and lateral are 12–18 long. Ventrianal shield 150–160 long, 435–480 wide, with transverse linear reticulation, 1 pair setae anterior of anus 10–12 long, 3 lateral pairs 18–22 long, paranal setae 27–28 long; anterolateral corner of ventrianal shield fused with ventral shield. Marginal shields with lineate reticulation.

Legs. TrI with seta pv 1 with minute barbs, not thicker than seta av 1. FeI with seta pv 3 similar to seta pv 1 and pv 2. FeII with lamella distal to seta pv 1, seta ad 1 smooth and thickened. FeIII without lamella, seta pv 1 not spine-like. FeIV enlarged, 205–222 long, 105–110 wide at distal end, without lamella, seta pv 1 not spinelike, seta pd 2 more proximal than seta ad 2. TaII and III with seta av 2 setiform, longer than seta av 3. Legs II – IV with thickened ad and pd setae, especially on femora and genua.

Gnathosoma   . Seta h 1 smooth, straight, 73–80 long, distance between h 1 -h 1 45–50; h 2 smooth 52–60 long; h 3 7–10 long, posterolaterad h 2; palpcoxal seta 16–17 long. Corniculi on tubercles ca. 10 long. Palp, seta av 1 on trochanter with 9–10 branches up to 18 long, seta av 2 with small barbs, spur with accessory spine. Chelicera, fixed digit 195–200 long, movable digit 69–73 long, fixed digit with 2 large and 2 minute teeth; excrescences arise from an enlarged base of digit and comprise a large brush-like process, a ribbon-like process with a serrate edge, and a ribbon-like process with a crenate and toothed edge; processes extend at least 90 past end of chelicerae.

Male: Idiosoma   . 1020–1050 long, 720–800 wide. Tetartosternum 23–29 long at midline, 83–90 wide; st 1 smooth, 30–42 long; st 2 smooth, 10–12 long; st 3 smooth, 22–25 long. Genital opening 69–78 long, 80–84 wide. Small, medial smooth areas level with Cx IV and just anterior of ventrianal shield. Suture behind genital opening separates smooth sternogenital shield from ventral shield. Ventral and ventrianal shield with meshlike reticulations. Gnathosoma   . Seta h 3 blade-like, 7–9 long, and posterior to h 2 and closer to midline than h 2. Palpcoxal seta 10–12 long.

Remarks. The sternal region of Mesostigmata   usually has four pairs of setae and three pairs of slit-organs (lyrifissures). Members of the Fedrizziidae   and Klinckowstroemiidae   have four pairs of setae, but appear to have three pairs of lyrifissures and a pore-like structure. Three lyrifissures are identifiable: in females, stp 1 is on the tetartosternum, stp 2 is on the sternal shield and stp 3 is on the sternogynial shield. The additional porelike structure is on the sternal shield. This structure is not shaped as a typical lyrifissure and probably represents a gland. Herein, I refer to this gland-like structure as stp x.

Lyrifissure stp 2 is posterior of stp x in most species of Fedrizziidae   . However, in F. abradoalves   and F. sellnicki   stp 2 is anterior of stp x ( Fig. 25 View FIGURES 22 – 26 ), and in F. bornemisszai   , F. c a r a b i and F. derricki   , stp 2 and stp x are level with each other.

An unusual positional change is that of seta h 2 and h 3 in male and female Fedrizziidae   and Klinckowstroemiidae   . In females, seta h 3 is tiny (<15 long), and setae h 1 and h 2 are large (> 30 long), but in males, the tiny seta is placed between the large setae ( Figs 4 View FIGURE 4 , 23, 24 View FIGURES 22 – 26 ). Therefore, either the position of h 3 changes, or seta h 2 takes on the form of seta h 3, and vice versa. The latter interpretation is used in the Klinckowstroemiidae ( Rosario and Hunter 1987)   , but I prefer the former explanation for the following reasons. The position of the tiny seta in male Fedrizziidae   is generally posterior of h 1, but anterior of the other large hypostomal seta ( Fig. 4 View FIGURE 4 b). However, in F. abradoalves   and F. s e l l n i c k i this seta is posterior of both the large hypostomal setae ( Figs 4 View FIGURE 4 a, 23). Therefore, the position of the small seta is variable. Additionally, the size of the small seta in the male is always similar to that of the female, further suggesting that seta h 3 in male Fedrizziidae   and Klinckowstroemiidae   is in an unusual position medial of seta h 2.

Etymology. The specific name is Latin for “shaven belly” and alludes to the smooth, bare region surrounding the genital opening.


Australian National Insect Collection