Pullimosina (Pullimosina) kesoni, Roháček, 2019

Roháček, Jindřich, 2019, First Sphaeroceridae (Diptera) endemic to Madeira - three new terricolous species of Spelobia and Pullimosina, Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) 59 (1), pp. 107-124 : 114-118

Pullimosina (Pullimosina) kesoni sp. nov.

( Figs 26–29 , 32–47 )

Type material. HOLOTYPE: Ƌ, labelled: “C. MADEIRA: Rabaçal env., 950 m, 5.9.2003, J. Rohá č ek leg.”, “sifting leaves in laurel forest”, “ Holotypus Ƌ Pullimosina (Pullimosina) kesoni sp. n., J. Rohá č ek det. 2018” (red label), “Mus. Silesiae Opava, Inv. č. d 097 4-2003”. The specimen (see Fig. 26 ) is intact, dry mounted on triangular pinned card ( SMOC) . PARATYPES: PORTUGAL: C. MADEIRA: same data as for holotype, 23 ♁♁ 20 ♀♀ ( SMOC, 2 ♁♁ 2 ♀♀ in NMPC); Ribeiro Frio, 900 m, sifting leaves in laurel forest, 12.ix.2003, 1 ♁ 1 ♀, J. Rohá č ek leg. ( SMOC). N. MADEIRA: Chão da Ribeira e do Seixal I, 32°47 ′ 37 ʺ N, 17°06 ′ 41 ʺ W, 570 m, 13.–20.iii.1997, pitfall traps A 9, ♁, B 11, 2 ♁♁, B 12, ♁ ♀, all Dília Menezes leg.; 18.ii.–10.iii.1997, pitfall trap B 1, 1 ♁ 4 ♀♀, no collector; Chão da Ribeira e do Seixal II, 32°48 ′ 12 ʺ N, 17°06 ′ 53 ʺ W, 462 m, 13.–20. iii.1997, pitfall traps D 10, ♁, E 1, ♁, F 10, 2 ♀♀, Dília Menezes leg. (all UMa). Some of above paratypes with genit. prep.

Note. The type locality (the same as for S. polymorpha described above) lies close to the forest house Rabaçal, about 32°45 ʹ 43 ʺ N, 17°08 ʹ 01 ʺ W ( Fig. 31 , for habitat see Fig. 30 ).

Description. Male ( Fig. 26 ). Total body length 1.62–1.95 mm; general colour brown to dark brown with greyish brown microtomentum, subshining dorsally (thorax, abdomen), duller laterally (thoracic pleuron) and ventrally (abdomen). Head ( Fig. 28 ) somewhat higher than long (ca. 5: 4), brown to blackish brown except for distinctly paler (ochreous to yellow) face. Frons dark brown, relatively sparsely microtomentose, partly shining; occiput blackish brown with similar microtomentum. Orbits, interfrontalia and ocellar triangle distinctly grey microtomentose; orbit separated from interfrontalia by blackish brown dull stripe (widened anteriorly); frontal triangle poorly delimited, long, reaching to anterior margin of frons and distinctly more shining than rest of frons. Cephalic chaetotaxy ( Fig. 28 ): pvt absent, only minute divergent postocellar setulae laterally behind ocellar triangle; occe and occi subequal (or occi slightly longer) and about two-thirds to three-fourth length of vti; vti robust and longest of frontal bristles; vte and oc somewhat shorter than vti; 2 ors, posterior as long as vte (or oc) but much (twice) longer than anterior ors; 3 ifr, middle pair robust (sometimes almost as long as oc), 2 others fine, small, only about half length of the former, sometimes with 1 microseta in front of anterior ifr in addition; 2–3 very minute ads inside and below ors; g weak, hardly longer than anterior peristomal setula; vi robust, about as long as vti; peristomal setulae (7–8) about as long as those in (single) postocular row; postgenal setae (3) relatively strong and curved. Frontal lunule short and wide, ochreous to yellowish ochreous, sparsely greyish microtomentose, contrasting with dark brown frons but concolorous with face. Face ochreous to dark yellow, usually darker dorsomedially and laterally; facial cavities below antennae relatively shining; medial carina developed, most distinct dorsally, below frontal lunule. Gena brown, paler anteriorly (with vibrissal angle ochreous), dark brown posteriorly, all greyish brown microtomentose. Eye subcircular (16:15), of moderate size, with longest diameter about 3.0 times as long as smallest genal height. Antenna brown to dark brown; 3rd segment (1st flagellomere) relatively short (not longer than scape + pedicel), suboval, with greyish white ciliation on apex distinctly longer than cilia on arista. Arista relatively long, about 4.1 times as long as antenna, shortly but densely ciliate.

Thorax dark brown to brown (pleuron) and dark greyish brown microtomentose; mesonotum subshining, pleuron and scutellum with denser microtomentum and duller. Sutures between pleural sclerites pale brown to ochreous. Scutellum large and flat on disc, transversely (5:3) rounded trapezoidal. Thoracic chaetotaxy: mesonotal macrosetae relatively short but robust; 1 hu and 2 microsetae on humeral callus; 3 postsutural dc but the most anterior small (but distinctly thicker and about 3 times as long as dc microsetae), two posterior dc robust but relatively short (the longer hindmost dc shorter than basal sc); 6 (rarely 7) rows of ac microsetae on suture; medial prescutellar ac pair prolonged, about as long as anterior dc; 2 long sc, laterobasal about as long as scutellum, apical (longest thoracic seta) 1.6 ‒ 1.7 times as long as laterobasal; 2 stpl but anterior reduced to small and fine setula.

Legs brown to dark brown, only coxae, trochanters, knees and tarsi pale brown to ochreous; fore coxa lightest, yellowish ochreous. Mid leg chaetotaxy: f 2 with 2 rows of short but slightly thickened (antero- and postero-) ventral setae (6–8 setae in each row) in proximal two-thirds. t 2 (contrary to that all European congeners except for P. dorae sp. nov.) ventrally with a long row of small dense spines and distinct (although shorter than in female) ventroapical seta and 1 small anteroapical seta (see Fig. 44 ; dorsal chaetotaxy of t 2 as in Fig. 40 : 1 anterodorsal seta in proximal fourth surmounted by 1–2 setulae, 1 anterodorsal seta in distal third (also surmounted by a shorter seta), 1 long dorsal seta in distal fifth and 1 shorter posterodorsal seta in distal fourth. f 3 somewhat thickened and shorter than in female. Ratio t

2: mt

2 = 1.83–1.91.

Wing ( Fig. 29 ) with distinctly brownish fumose membrane (darkest along veins) and brown to dark brown veins. C produced far beyond apex of R 4+5. R 2+3 very slightly sinuate but apically distinctly upcurved to C; R 4+5 basally almost straight, distally slightly upcurved to C but diverging from and ending distinctly farther from apex of wing than venal fold of M. Discal cell (dm) rather short, distally broad, with short to minute processes of M and CuA 1 beyond dm-cu (that of CuA 1 longer) which continue by colourless folds; both outer corners of dm cell obtuse-angled. A 1 reduced, short. Anal lobe large, well developed; alula relatively small and narrow. Wing measurements: length 1.54–1.71 mm, width 0.68–0.77 mm, C-index = 0.95–1.08, rm\dm-cu: dm-cu = 1.25–1.60. Haltere pale brown to brown, with ochreous stem.

Abdomen blackish brown dorsally, brown ventrally. Preabdominal terga broad and relatively shining because of sparse greyish microtomentum, T2–T5 sparsely and relatively shortly setose, with longest setae in posterior corners. T1+2 largest tergum (somewhat longer than T3 and T4 together), not desclerotized and/or depressed medially but paler brown on original T1 (lightest medially) being delimited from original T2 by a transverse wrinkle. T3‒T5 becoming narrower posteriorly, T5 smallest. Preabdominal sterna: S1+2 small, reduced to inconspicuous, very pale (submembranous) and bare sclerite; S3 and, particularly S4 large, broad, brown and heavily sclerotized; S3 transversely trapezoidal, narrower anteriorly and smaller than S4, the latter the largest sternum, transversely suboblong and distinctly longer than (equally broad) S5. S3 and S4 with shorter and finer setae than adjacent terga. S5 ( Fig. 33 ) transverse, slightly asymmetrical, with short posteromedial submembranous and finely haired lappet and two groups of longer and denser setae laterally in front of the latter, otherwise relatively sparsely setose. S6+7 strongly asymmetrical, shifted on left side of postabdomen, S8 less asymmetrical and situated dorsally. S6+7 with anterior dark-pigmented ledge and with posteroventral dark projection bent inside postabdomen; both S6+7 and S8 with only a few small setae.

Genitalia: Epandrium ( Figs 35, 37 ) relatively short, of medium width but slightly asymmetrical in caudal view, more convex left dorsolaterally ( Fig. 35 ), with 1 very long and robust dorsolateral seta, otherwise with sparse small setae, only some of them at margin of anal fissure longer. Anal fissure relatively large, broadly suboval. Cerci short, fused with epandrium and medially forming subanal (ventromedially acutely incised) plate but lines of fusion remain visible ( Figs 35, 37 ); each cercus with 1 longer and several short setae. Medandrium somewhat X-shaped in caudal view, hence broad dorsally and most narrowed in the middle, fused with cerci posteromedially and ventrally connected with gonostyli ( Fig. 35 ). Hypandrium roughly Y-shaped in dorsal view, with anteromedial rod-like apodeme, smaller paired lateral sclerites, and more medially with minute sclerites connecting hypandrium with postgonites (cf. Fig. 32 ). Gonostylus ( Figs 35–37 ) of distinctive shape, long acutely projecting posteroventrally and with smaller acute process also in the middle of anterior margin; outer side with very long sinuous setae on most of surface, and, in contrast to all congeners, with 1–2 short robust and dark spines between both above projections (see Fig. 36 ). Aedeagal complex ( Figs 32, 34 ). Phallapodeme longer and more robust than hypandrial apodeme, with well-developed dorsal keel. Aedeagus with compact, laterally flattened phallophore ( Figs 32, 34 ) and relatively short distiphallus. Distiphallus basally formed by a distally tapered dorsal plate ( Fig. 34 ) and a pair of lateral slender sclerites ( Fig. 32 ); its larger and wider distal part composed of wing-like (ventrally connected) lateral sclerites, each of which carries dorsally a group of small dark spinulae ( Fig. 34 ). Dorsomedial sclerotization between the latter sclerites complex, with distinct medial spike-like process (not visible in lateral view); postgonite relatively large (longer than distiphallus), broad proximally, strongly tapered distally but with apex not acute, with a minute preapical tooth anteriorly, 2–3 microsetae (both anteriorly and posteriorly) in distal fourth and with minute sclerite (= remnant of pregonite) with 2 setulae, inserted into anterodorsal emargination of postgonite ( Fig. 32 ). Ejacapodeme reduced to very minute rod-like sclerite (see Fig. 32 ) attached to ejaculatory duct.

Female ( Fig. 27 ). Similar to male unless mentioned otherwise below. Total body length 1.74–2.05 mm. ifr often more robust, particularly the anterior and 1 microseta in front of the latter more distinct and almost regularly present. Legs sometimes with tibiae pale brown to ochreous. f 2 ventrally simply setulose, without two rows of thicker curved setae; t 2 ventrally with 1 short ventral seta near middle and 1 long (longer than in male) ventroapical seta ( Fig. 41 ); dorsal chaetotaxy as in male but some setae (the long distal dorsal seta in particular) often longer ( Fig. 40 ); also small anteroapical seta usually somewhat longer. mt 2 relatively longer, also f 3 longer and less thickened than in male. Ratio t 2: mt 2 = 1.64–1.76. Wing measurements: length 1.62–1.87 mm, width 0.73–0.84 mm, C-index = 0.98–1.14, rm\dm-cu: dm-cu = 1.27–1.54. Preabdominal terga distinctly shorter, more transverse; T1+2 shorter than T3 and T4 together; T3–T5 becoming narrower posteriorly, similarly setose as in male. Preabdominal sterna S3–S5 sparsely and shortly setose, subshining due to sparse microtomentum. S1+2 very reduced, bare and submembranous as in male; S3–S4 large, similarly formed but more transverse than in male; S4 largest and widest sternum, about as long as S3; S5 unmodified, transversely suboblong, narrower and distinctly shorter than S4; all these sclerites dark brown, heavily sclerotized.

Postabdomen ( Figs 38, 39, 45 ) relatively short and broad, with sparsely setose sclerites. T6 transversely suboblong but narrower than S6, with both anterior and posterior margins pale and setae in posterior half ( Fig. 38 ); T7 slightly shorter than T6 and bent farther onto lateral side (see Fig. 45 ) and seemingly narrower in dorsal view, with pale posterior margin and only single row of setae in front of it. T8 dorsomedially membranous, unpigmented, appearing to be divided into two lateral sclerites ( Figs 38, 45 ), each with 1 long and a few small setae. T10 transversely subrhomboidal, distinctly wider than long, largely pale-pigmented, finely micropubescent and with a pair of relatively short setae in the middle ( Fig. 38 ). S6 much wider, more transverse and more setulose than both T6 and S7, having all margins pale-pigmented ( Figs 39, 45 ). S7 simple, transversely suboblong, slightly wider than T6, with setae only at posterior margin. S8 ( Figs 39, 46 ) only slightly larger than S10, of suboval outline (in largest extension view, see Fig. 46 ), convex in the middle, posteriorly with a slightly projecting lobe provided with a pair of dark bent ledges, with only sparse setulae except for a pair of longer lateral setae. Additional sclerite between S8 and S10 (covered by S 8 in ventral view, Fig. 39 ) well developed and dark-pigmented, bare, bent, with slender, dark and posteriorly projecting lateral ledges ( Fig. 46 ). S10 about half-length of S8, transversely pentagonal, pale pigmented, micropubescent and setulose in posterior half, medially with a pair of longer setae ( Fig. 46 ). Spectacles-shaped sclerite (= sclerotization of female genital chamber) oriented vertically (see in situ, Fig. 45 ), elongate, with relatively small rings ( Figs 42, 43 ). Spermathecae 2+1 ( Fig. 47 ) blackish brown, each of relatively robust tyre-shaped form, with very finely densely ringed surface, deep subconical terminal invagination (with distinct spinule inside), terminal parts of ducts well-sclerotized, somewhat conically dilated towards insertion and provided with small dark tubercles. Cerci ( Figs 38, 45 ) slender, tapered towards terminal seta, micropubescent, each with 4 setae, the dorsopreapical and apical long and sinuate, the latter longer than length of cercus.

Comments. Pullimosina kesoni sp. nov. and its closest relative P. dorae sp. nov. are among the largest species of the genus. Both distinctly belong to the subgenus Pullimosina (s. str.) antennata group as delimited by MARSHALL (1986) because of possessing cruciate middle ifr setae, densely and long setose gonostylus, distiphallus with spinose or toothed distal sclerites and a well-developed additional sclerite between female S8 and S10.

Because of its yellow to ochreous face P. kesoni habitually most resembles P. dorae sp. nov. (Madeira, described below), P. pullula (Zetterstedt, 1847) (Holarctic) , P. meijerei ( Duda, 1918) (European) , P. geminata Marshall, 1986 and P. vockerothi Marshall, 1986 (both Nearctic), but except for the first and perhaps the latter none of the remaining species seem to be its close relative. Based on structures of the male and female terminalia P. dorae is obviously the nearest ally of P. kesoni . Surprisingly also the Mexican P. mcalpinei Marshall, 1986 could be more related to P. kesoni , resembling the latter in the shape of gonostylus, postgonite and apex of distiphallus ( MARSHALL 1986: figs 69, 70) and in larger size of body while the formation of female postabdominal sclerites is very dissimilar in these two species. Pullimosina kesoni seems to be unique among Pullimosina species in having a gonostylus ventrally armed by 1–2 robust spines (see Fig. 36 ) in addition to posterior and anterior acutely projecting corners. Note: a short thick spine-like seta (albeit much smaller) is also illustrated on the gonostylus of P. meta Su, 2011 on apex of anterior gonostylar projection (see SU 2011: figs 51e,f) but this was corrected subsequently by SU et al. (2013, fig. 4f) to be only a pointed apex of this projection.

The male pregenital sternum (S5) of P. kesoni resembles most that of P. dorae but differs in having a posteromedial membranous lappet and less dense clumps of setae near the latter ( Fig. 33 ). Although having a very similarly constructed distiphallus, these two species have a quite dissimilar postgonite (distally tapered and slender in P. kesoni while dilated and robust terminally in P. dorae ). Further distinct differences can be seen in the female postabdomen: T8 is dorsomediallly short and broadly desclerotized in P. kesoni ( Fig. 38 ) while continuous and robust in P. dorae ( Fig. 58 ), S8 is posteromedially abruptly narrowed and with a pair of dark strips in P. kesoni ( Fig. 46 ) but rounded and anteromedially with a ventrally protruding bulge in P. dorae ( Fig. 62 ), additional sclerite short (transverse) and with marginal dark ledges laterally in P. kesoni ( Fig. 46 ) while longer and with 2 lobes posterolaterally in P. dorae ( Fig. 61 ), also the spectacles-shaped sclerite (although with similarly elongate and vertically positioned medial sclerite) is distinctly different in having small, closely situated rings in P. kesoni ( Fig. 43 ) and larger more separate rings in P. dorae ( Fig. 64 ) and the spermathecae are rather tyre-shaped in in P. kesoni ( Fig. 47 ) while more vesicular in P. dorae ( Figs 59, 60 ).

Etymology. The species is dedicated to my friend from school-days, Ing. Antonín Nosek (Jihlava, Czech Republic), using his nickname from grammar-school “Keson” (= anagram of Nosek).

Biology. All studied specimens were collected in montane laurel forests ( Figs 6 , 31 ), either sifted from rotting leaves and detritus (microhabitat on Figs 7 , 30 ) or captured into pitfall traps installed in the same habitat. Observation of living specimens showed that they practically do not fly, only run or skip among forest litter. Consequently, P. kesoni seems to be a terricolous species living on the ground under the layer of decayed leaves of laurel trees. Adults were recorded in February, March and September

Distribution. Madeira, mainly recorded from localities with a well preserved Laurisilva ecosystem, more rarely (Chão da Ribeira e do Seixal II) in that partly degradated with some introduced exotic plants (all occurrence sites mapped in Fig. 69 ).

Figures

Figs 26–31. Pullimosina (Pullimosina) kesoni sp. nov. (Madeira) and its habitat. 26 – male holotype, laterally (body length 1.7 mm); 27 – female paratype, laterally (body length 1.8 mm); 28 – head, laterally, male holotype; 29 – wing, male paratype (length ca 1.7 mm); 30 – microhabitat, rotting leaf litter in ditch (arrow) along path in laurel forest nr. Rabaçal; 31 – upper part of valley of Ribeira de Janella nr. Rabaçal (type locality of both S. polymorpha and P. kesoni). Photo by M. Tkoč (26–28) and J. Roháček (others).

Figs 32–37. Pullimosina (Pullimosina) kesoni sp. nov., male paratype (Madeira). 32 – aedeagal complex, laterally; 33 – S5, ventrally; 34 – aedeagus, dorsally; 35 – external genitalia (aedeagal complex omitted), caudally; 36 – gonostylus, sublaterally (widest extension); 37 – genitalia, laterally. Scales = 0.05 mm (Fig. 36), 0.1 mm (others). For abbreviations see pages 108–109.

Figs 38–47. Pullimosina (Pullimosina) kesoni sp. nov., female and male paratypes (Madeira). 38 – female postabdomen, dorsally; 39 – ditto, ventrally; 40 – female t2 dorsally; 41 – ditto, anteriorly; 42 – spectacles-shaped sclerite, laterally; 43 – ditto, posteroventraly; 44 – male t2 anteriorly; 45 – female postabdomen, laterally; 46 – sclerites of 8th segment and S10, ventrocaudally; 47 – spermathecae. Scales = 0.1 mm (Figs 38, 39, 45, 46), 0.03 mm (Figs 42, 43, 47), 0.2 mm (others). For abbreviations see pages 108–109.

Figs 58–68. Pullimosina (Pullimosina) dorae sp. nov., female and male paratypes (Madeira). 58 – female postabdomen, dorsally; 59 – spermatheca; 60 – paired spermathecae; 61 – female additional sclerite, posteroventrally; 62 – female postabdomen, ventrally; 63 – female postabdomen, laterally; 64 – spectacles-shaped sclerite, ventrally; 65 – ditto, laterally; 66 – female t2 dorsally; 67 – ditto, anteriorly; 68 – male t2 anteriorly. Scales = 0.1 mm (Figs 58, 61–63), 0.03 mm (Figs 59, 60, 64, 65), 0.2 mm (others).

Figs 1–7. Spelobia polymorpha sp. nov. (Madeira) and its habitat. 1 – male holotype, laterally (body length 2.1 mm); 2 – female paratype, laterally (body length 2.9 mm); 3 – wing, f. brach., male paratype (length ca 1.3 mm); 4 – wing, f. brach., male paratype (length ca 1.6 mm); 5 – wing, f. submacropt., male paratype (length ca 2.3 mm); 6 – laurel forest on slopes near Ribeiro Frio; 7 – microhabitat in laurel forest, rotting fallen leaves on ground (arrow) in the same locality. Photo by M. Tkoč (1, 2) and J. Roháček (others).

Fig. 69. Map of Madeira Island with all known localities of Spelobia polymorpha, Pullimosina kesoni and P. dorae spp. nov. The extent of original distribution of montane laurel forests (named Laurissilva do Til in the lengend) is in dark green colour.