Iratiquedius mutator (Smetana, 1971) Brunke, 2022

Brunke, Adam J., 2022, A world generic revision of Quediini (Coleoptera, Staphylinidae, Staphylininae), part 1. Early diverging Nearctic lineages, ZooKeys 1134, pp. 129-170 : 129

Iratiquedius mutator (Smetana, 1971) comb. nov.

Figs 2C, D , 4C, D , 6C, D, G, J, K , 9B , 11A (map)

Quedius (Raphirus) mutator Smetana, 1971: 206.

Quedius (Raphirus) mutator : Smetana 1990 (distributional records, misidentification of Q. amabilis , in part).

Type locality.

8 miles north of Post Pile Camp [possibly 'Valentine Spring’, ~ 1660 m], Tehama County, California, United States.

Type material.

Holotype (female, CNC): 8 mi N Post Pile Camp, Tehema [Tehama] Co., Cal, VIII-30-60 [handwritten label] / R.O. Schuster Collector [printed label] / HOLOTYPE Quedius mutator Smetana 1968, CNC No. 10877 [red printed label] / CNC [handwritten label] / CNC93512 [identifier].

The female holotype has the shortest, most sparsely punctate elytra of all known individuals attributed here to either I. mutator or I. amabilis . The shape of female tergite X is unique and differs from the other examined females (here attributed to I. amabilis ) by the projected, sharp apex (Fig. 9B ).

Non-type material.

United States: California: Butte Co.: 3 mi NE Loma [Loma Rica], 39.354, -121.411, 151 m, 3.V.1981, sifting litter along spring, D. Chandler (2 males, FMNH).

Diagnosis.

Iratiquedius mutator may be recognized within the genus by a combination of the evenly punctate elytra, the lack of golden setae or impressions at the base of the abdominal tergites and the indistinct micropunctures on the anterior angles of the pronotum. The species most closely resembles I. amabilis and can be distinguished from it by the indistinct micropunctures of the anterior angles of the pronotum, the longer apex of the median lobe in lateral view in males or sharp, pointed apex of female tergite X.

Redescription.

Measurements ♂ (n = 2): HW/HL 1.22-1.25; PW/PL 1.20-1.24; EW/EL 1.37-1.38; ESut/PL 0.68-0.71; PW/HW 1.21-1.23; forebody length 3.4-3.5 mm.

Measurements ♀ (n = 1): HW/HL 1.20; PW/PL 1.22; EW/EL 1.70; ESut/PL 0.58; PW/HW 1.16; forebody length 2.8 mm.

Extremely similar to I. amabilis , and differing only in the following: antennomeres 1-4 (macropterous) or 1-3 (brachypterous) clearly elongate; pronotum moderately (macropterous) to weakly (brachypterous) transverse; pronotum with micropunctures of anterior angles indistinct (Fig. 4C, D ); elytra overall shorter, and at suture relatively shorter than pronotum when comparing morphotypes; male sternite VIII with emargination vaguely more rounded at middle but varying from moderately narrow to as wide as I. amabilis ; male tergite X more slender with narrower apex; male sternite IX broader, more strongly convergent to apex; apex of median lobe in lateral view longer, more elongate and sharp (Fig. 6C, D ), median lobe in ventral view with apex entire and pointed (Fig. 6G ); paramere with marginal row becoming sparser distally (Fig. 6J, K ); apex of female tergite X sharply projected to a point, with sparse marginal setae (Fig. 9B ).

Distribution.

United States: CA.

This species is known only from two localities: one in the mountains of the northern Coast Range and one in the Central Valley region.

Bionomics.

Both known localities are at least near springs, within areas of relatively dry, open woodland. Specimens of strongly hydrophilous species I. uncifer and I. prostans were co-collected at the type locality. The two non-type males were collected in litter along the margins of a spring. The holotype was collected at around 1600 m, while the non-type males were collected around 150 m.

Comments.

The concept given here for Iratiquedius mutator is considered to be a step forward but may need to be modified in the unlikely case that the population in the Central Valley is a third, undescribed species. Males from near the type locality will be needed to determine this with certainty.

Figures

Figure 2. A-H dorsal habitus of A, B Iratiquedius amabilis (Smetana) A male holotype B female non-type C, D I. mutator (Smetana) C male non-type D female holotype E I. prostans (Horn) F I. seriatus (Horn) G Paraquedius puncticeps (Horn) H P. marginicollis sp. nov. Scale bars: 1 mm.

Figure 4. A-D anterior angle of the pronotum A, B Iratiquedius amabilis (Smetana) C, D I. mutator (Smetana) A, C macropterous morphotype B, D brachypterous morphotype. Scale bars: 0.1 mm.

Figure 6. A-G, L-O median lobe of aedeagus A-D, N, O in lateral view E-G, L, M in ventral view O with internal sac everted H-K, P underside of paramere showing peg setae A, B, E, F, H, I Iratiquedius amabilis (Smetana) C, D, G, J, K I. mutator (Smetana) L-P I. prostans (Horn). Scale bars: 0.1 mm.

Figure 9. A-I female tergite X A Iratiquedius amabilis (Smetana) B I. mutator (Smetana) C I. prostans (Horn) D I. seriatus (Horn), evenly convex E I. uncifer sp. nov., discal impression F Paraquedius puncticeps (Horn) G P. marginicollis sp. nov. H-I Quediellus debilis (Horn). Pigmented area on tergite in E not shown for clarity but similar to I. seriatus. Scale bars: 0.1 mm.

Figure 11. Distributions of A Iratiquedius amabilis (Smetana) (circles), I. mutator (Smetana) (squares) B I. prostans (Horn) (black - specimens examined, white - literature records) C I. seriatus (Horn) (circles), I. uncifer sp. nov. (squares) D Paraquedius puncticeps (Horn) (circles), P. marginicollis sp. nov. (squares) E Quediellus debilis (Horn) (circles) (black - specimens examined, white - literature records).