Thinodromus gildenkovi, Makranczy, 2013

Makranczy, György, 2013, Review of the southern African species of Thinodromus (Coleoptera: Staphylinidae: Oxytelinae), Acta Entomologica Musei Nationalis Pragae 53 (1), pp. 177-208 : 182-183

Thinodromus gildenkovi sp. nov.

( Figs 1 , 20–21, 24–25 , 32–33 , 43–45 , 48–49 , 84 )

Type locality. Botswana, North-East Prov., river Shashe, 20 mi NW Francistown.

Type material. HOLOTYPE: ♂, “ Botswana (B24); [North-East Prov.] R. Shashe, 20 mls.; NW. Francistown [approx. 21°01′04″S, 27°14′22″E, 1050 m]; 24.iv.1972 \ at; light \ Southern; African Exp.; B.M. 1972-I \ Thinodromus ; af. segnis (Er.); 1999; det. M. Gildenkov ” ( BMNH). PARATYPES (3 specimens): same data as holotype (2 ♀♀, BMNH; 1 ♂, MGSC) .

Description. Measurements (in mm, n = 3): HW = 0.60 (0.585–0.60); TW = 0.53 (0.51–0.545); PW = 0.69 (0.655–0.70); SW = 0.85 (0.81–0.88); AW = 0.92 (0.88–0.95); HL = 0.39 (0.38– 0.40); EL = 0.24 (0.225–0.24); TL = 0.03 (0.025–0.04); PL = 0.51 (0.49–0.53); SL = 0.83 (0.80–0.85); SC = 0.75 (0.72–0.78); FB = 1.73 (1.64–1.80); BL = 3.17 (3.00–3.47). Lustre and colour: Body ( Fig. 1 ) rather dull, due not only to punctation but extremely fine and dense setation providing greyish, dusted appearance. Forebody and abdomen pitch black, legs dark brown but both ends of tibiae (plus tarsi) significantly lighter, reddish-yellowish. Mouthparts and antennae dark brown, basal antennomeres not lighter, but even a little darker. Shape and sculpture: Head ( Fig. 32 ) strongly transverse, eyes large, occupy sides of head, leaving free just discernible temples. Pronotum strongly transverse, first half of sides and anterior corners broadly rounded, hind half a little concave; posterior corner obtuse-angled and rounded but conspicuous. Horseshoe-shaped impression deep but rather broad, therefore less prominent, pronotal disc laterally with shallow depressions, middle of disc slightly elevated, this point often more shiny than surroundings, with two smaller impressions laterally. Deflexed margin thin, laterally discernible on whole length, just slightly more apparent in posterior half, on posterior margin present but hardly visible (covered by setation). Elytra ( Fig. 33 ) combined significantly broader than long, dilated towards apex, with a small round impression posterior of scutellum and a larger oblique depressed area at anterior half of disc. Apical margin of elytron with a concavity and membranous lobe in outer 1/3, not apparent on whole width. Apex of abdominal tergite VII ( Fig. 21 ) with palisade fringe (widest medially). Punctation and microsculpture: Head punctation rather dense, interspaces mostly just a fraction of puncture diameters. Punctures varying in size but deep, surface covered by coriaceous microsculpture. Pronotal punctures a little larger but almost as dense, microsculpture becomes stronger, more scabrous along sides and posterior edge. Elytral punctures larger and dense, despite small interspaces some microsculpture obvious. Abdominal tergites with punctures smaller and less dense than on elytra but in interspaces with coriaceous microsculpture turning stronger in grooves behind basal ridges. Pubescence: Body covered by remarkably short and rather dense setation, setae with not so even sizes but equal spacing therefore appearing uniform, some longer setae near posterior margins of abdominal terga; setae rather pressed down, their direction most obvious on head where uniformly anterior. Primary and secondary sexual features. Male antennae unusually elongate, middle antennomeres (articles 4–5) about twice as long as broad and penultimate antennomeres (articles 9–10) a little bit longer than broad in male ( Fig. 25 ), female antennae ( Fig. 24 ) a little less elongate. Male: MA of aedeagal internal sac appears short and stout, ML very transverse, BM tiny and thin, but a distal, wider sclerite seems to be disassociated from it, they may have been modified from a single sclerite, BA rather long and more or less straight, AC reverse V-shaped with arms open in nearly right angle ( Figs 43–45 ), sternite VIII ( Fig. 48 ), tergite X ( Fig. 49 ); female: ringstructure and spermatheca ( Fig. 84 ).

Differential diagnosis. Thinodromus gildenkovi sp. nov. is rather closely allied to T. dasys , the female ringstructure is of similar shape, although the basal loops are with more rounded and uniformly lamellar apex, the apical part is not slightly pointed but rather evenly curved in T. gildenkovi , although in the proximity of the apex the pores have more dense patches in both species. The aedeagus of both species is of the same general shape and similar sclerotization pattern in the parameres, although the latter differs in form on the backside flaps. The central sclerotized plate in the subapical edge of the median lobe body is not pointed but more or less trunctate/concave at the apex, the apical part of this stucture is rather elongate. The medial tooth adjacent to ML is similarly bulky but other associated sclerites are different, as well as BA much more slender and elongate in T. gildenkovi sp. nov., lacking the incrassate and truncate apex. AC is more elongate in this species, but of the same general shape, without apical projection.

Etymology. Named after Mikhail Yurievich Gildenkov (Smolensk, Russia), who added greatly to our knowledge of the Oxytelinae , primarily by his pioneering studies on Palaearctic Carpelimus Leach, 1819 and for his helpful contributions toward the work presented here.

Distribution. Only known from Botswana.

Figures

Figs 1–3. Habitus of Thinodromus species. 1 – T. gildenkovi sp. nov., male; 2 – T. meridionalis sp. nov., female; 3 – T. facilis Gildenkov, 2000, female.

Figs 19–27. 19 – Thinodromus facilis Gildenkov, 2000, female protarsus; 20 – T. gildenkovi sp. nov., male protarsus; 21 – T. gildenkovi sp. nov., male, fringe of tergite VII. Antennae. 22 – T. sudanensis (Scheerpeltz, 1974), female; 23 – T. meridionalis sp. nov., female; 24–25 – T. gildenkovi sp. nov. (24 – female; 25 – male); 26–27 – T. dasys Gildenkov, 2000 (26 – female; 27 – male) Scale bar: 0.065 mm for 19, 0.08 mm for 20, 0.12 mm for 21, 0.24 mm for 24–25, 0.3 mm for 22 and 26–27, 0.33 mm for 23.

Figs 28–33. 28–31 – Thinodromus tibialis (Fauvel, 1907) (28 – head and pronotum; 29 – female antenna; 30 – male antenna; 31 – elytron and abdominal base); 32–33 – T. gildenkovi sp. nov. (32 – head and pronotum; 33 – elytron and abdominal base). Scale bar: 0.45 mm for 28–31, 0.55 mm for 32–33.

Figs.40–45.40–42 – Thinodromus dasys Gildenkov, 2000, male (40–41 – aedeagus; 42 – paramere);43–45 – T.gildenkovi sp. nov., male (43–44 – aedeagus; 45 – paramere). Abbreviations: AC – apical copulatory sclerite; BA – basal sclerites, BM – basomedial sclerites, MA – medioapical sclerites ML – medial lamellae. Scale bar: 0.10 mm for 43–45, 0.12 mm for 40–42.

Figs 46–51. 46–47 – Thinodromus dasys Gildenkov, 2000, male (46 – sternite VIII; 47 – tergite X); 48–49 – T. gildenkovi sp. nov., male (48 – sternite VIII; 49 – tergite X); 50–51 – T. rhodesianus (Scheerpeltz, 1974), male (50 – sternite VIII; 51 – tergite X). Scale bar: 0.10 mm for 49 and 51, 0.13 mm for 47–48 and 50, 0.15 mm for 46.

Figs 81–85. 81–83 – female ringstructures.81 – Thinodromus tibialis (Fauvel, 1907); 82 – T. dasys Gildenkov, 2000; 83 – T. nigerius Gildenkov, 2000. 84–85 – female ringstructures with spermathecae. 84 – T. facilis Gildenkov, 2000; 85 – T. gildenkovi sp. nov. Scale bar: 0.10 mm for 85, 0.12 mm for 81 and 83–84, 0.14 mm for 82.