Amygdalops sparsus, Jindr & Rohác & ek, 2004

Jindr, Rohác, ich & ek, 2004, Revision of the genus Amygdalops Lamb, 1914 (Diptera: Anthomyzidae) of the Afrotropical Region, African Invertebrates 45, pp. 157-221 : 198-203

Amygdalops sparsus sp. n.

( Figs 88–98 , 130 )

Type material: Holotype male, labelled: ‘ UGANDA: S.W., Semiliki Forest , 1250 m, 8.i.1996, 1 male, I. Yarom & A. Freidberg’ leg. ( TAUI, genit. intact) . Paratypes: CAMEROON: Rt. N 4, 120 km NW Yaounde , 5.xi.1987, 1 male, A. Freidberg leg. ( TAUI, genit. prep.) ; N’Kolbisson , 11.iv.1964, light trap, 1 female,? Tsacas leg. ( MNHN, genit. prep.) ; IVORY COAST: Lamto , frange Aframomum , Gal-E 2, 20.i.1071, 1 male ,

A. Lachaise leg. ( MNHN, genit. prep.); UGANDA: same data as for holotype, 4 males 4 females ( TAUI, 1 male 1 female SMOC, genit. prep.) .

Etymology: The name ‘sparsus’ (= Lat. spotted) is selected for the species which has strikingly variegated wings with white spots.

Description: Male.

Total body length 1.67–2.00 mm; bicolorous, blackish brown and pale yellow.

Head: As high as long. Occiput dark to blackish brown. Frons blackish brown except for yellow anterior fifth. Frontal triangle not very narrow, reaching only over half of frons, bare and shiny including ocellar triangle. Orbit also bare and shining dark brown, with only anterior fifth yellow. Stripes between orbits and frontal triangle dark grey microtomentose and dull. Face ochreous; narrow parafacialia and gena white and silvery white microtomentose; gena with ochreous ventral margin and ventral part of postgena pale yellow. Mouthparts yellow but palpus darkened, ochreous brown. Cephalic chaetotaxy: pvt short, with apices crossed; vti about two-thirds of vte; vte and posterior ors subequal and longest among cephalic setae; oc as long as vti; 2 long ors, anterior slightly to distinctly shorter than posterior) and 2 usual ors microsetulae in front of anterior ors; 1–2 pairs of microsetulae medially in front of frontal triangle; 1 long vi and 1 subvibrissa being as long as two-thirds of vi; peristomal setulae few and becoming longer anteriorly; postoculars very minute; seta on palpus distinct. Eye with longest diameter about 1.5 times as long as shortest one. Gena very narrow; its smallest height about 0.08 times as long as shortest eye diameter.Antenna yellow, with dorsal corner of pedicel and outer side of 1st flagellomere (particularly in basal half) darkened, ochreous. Arista about 1.9 times as long as antenna, long pectinate, particularly dorsobasally.

Thorax: Markedly narrower than head. Mesonotum including scutellum dark to blackish brown, subshiny; humeral and notopleural areas also brown. Pleural part of thorax with dark brown dorsal band; ventral portion of pleura pale yellow. Thoracic chaetotaxy: 1 very small prs; 2 dc, posterior very long and as long as apical sc, anterior very reduced, only slightly longer than dc microsetae in front of it; 2 sc, laterobasal short but markedly longer than anterior dc; 1 ppl, very minute or indistinct; 2 stpl, anterior weak, about two-thirds of more robust posterior one; setae on ventral part of sternopleuron few and hair-like. Scutellum slightly convex dorsally. Legs yellow to pale ochreous-yellow, f 2 and f 3 with darkened distal third or two-fifths, brown on f 2 and dark brown on f 3. Chaetotaxy of legs as in other relatives but posteroventral setae on f 1 relatively few; f 3 with posteroventral row of setae which are very short and dense in apical third. Wing ( Fig. 130 ) pattern characterised by dark apical third and by 2 rounded, white, iridescent spots, one between R 2+3 and R 4+ 5 in front of terminal dark spot, the other behind posterior (dm-cu) cross-vein; subapical dark spot large. R 2+3 and R 4+5 very strongly sinuous because of anterior white spot; M relatively straight. Discal (dm) cell relatively long, with r-m situated in front of its middle. A 1 very short in consequence of reduced anal lobe. Wing measurements: length 1.78–2.06 mm; width 0.53–0.64 mm, Cs 3: Cs 4 = 2.00-2.59, r-m\dm-cu: dm-cu = 2.92–3.33. Haltere with pale yellow stem and blackish brown knob.

Abdomen: Preabdominal terga large, completely blackish brown. T6 small, transverse, desclerotised and very pale ochreous pigmented. Preabdominal sterna brown, becoming darker and larger (wider) posteriorly, S5 the largest sternum, posteriorly widened and with emarginate posterior margin. S6–S8 blackish brown, dorsolaterally fused; S6 with slender ventral projection reaching to right side of abdomen.

Genitalia: Epandrium hemispherical, medium-long ( Figs 88, 89 ), setose also in anterior half; all setae relatively fine, dorsomedial pair only slightly longer than others; anal opening small, rounded subtriangular ( Fig. 88 ). Cercus medium-long, finely setose. Medandrium ( Fig. 88 ) comparatively wide and high. Gonostylus ( Fig. 91 ) long compared to epandrium, elongately triangular (in widest extension view), strongly tapered apically, apex slightly bent anteriorly but not very acute; micropubescence covering most of outer side except apex, dorsal and anterior margins; inner side with longer setae, particularly at anterior margin. Hypandrium ( Figs 90, 92 ) relatively moderate, heavily sclerotised, with hyaline, membranous internal lobes; transandrium simple and slender, slightly concave ventrally; caudal process composed of 2 long and slender band-like sclerites, which are fused dorsally and divergent ventrally. Pregonite ( Fig. 90 ) unusually protruding ventrally, dark, with 2 setae on anterior bulge and 4–5 shorter on posterior slender projection. Postgonite ( Figs 90, 92 ) slightly bent, slender, with blunt apex and several small sensilae on outer surface as usual; basal sclerite attached to postgonite large, pale pigmented and rounded, with finely wrinkled microsculpture.Aedeagal part of folding apparatus attached to base of phallapodeme ( Fig. 93 ) darkened dorsally, provided by flat, tooth-like, densely arranged spines; connecting sclerite long, and pale pigmented. Basal membrane ( Fig. 90 ) practically unarmed, without spines or tubercles. Aedeagal complex ( Fig. 93 ) with moderate phallapodeme, having usual bifurcate base and simple apex.Aedeagus with small (slightly longer than high) phallophore and large distiphallus. Base of distiphallus bare. Saccus of distiphallus large, except for sclerotised base membranous and covered by spines, which are small and dense on apex, longer on most other membranous part; basal pigmented part and short intervening area at apical two-thirds of saccus bare. Filum of distiphallus formed by 2 dark, very slender, stripelike, twisted and closely attached sclerites diverging in membranous dilated apex. Ejacapodeme small, with slender digitiform projection.

Female differs from male as follows:

Total body length 1.98–2.62 mm.

Anterior margin of frons, face, dorsal mouthparts and palpus distinctly darker than in male, pale to dark brown. Antenna dark ochreous to pale brown. Humeral callus sometimes lighter brown than mesonotum. f 3 posteroventrally simply setulose. Wing measurements: length 2.14–2.50 mm, width 0.67–0.75 mm, Cs 3: Cs 4 = 2.18–2.50, r-m\dm-cu: dm-cu = 2.88–3.35. Abdomen with preabdominal terga shorter and more transverse, blackish brown. Preabdominal sterna all brown and very narrow (except for S1–S2 all others longer than broad) in contrast to very broadened S6 (see Fig. 97 ).

Postabdomen ( Figs 94, 97 ) relatively slender and entire dark brown. T6 large, only slightly narrower and shorter than T5, densely shortly setose. S6 broad and transverse, markedly wider than S5, and about as wide as T7 anteriorly. T7 dark brown, narrow, posteriorly conically tapered, and reaching on ventral side of abdomen, with anteroventral corners meeting ventrally with anterior part of S7. S7 very slender, elongate, with sinuous lateral margins and pale pigmented medial stripe and setae on slightly dilated posterior third ( Fig. 97 ). T8 small, plate-shaped, with rounded posterior corners and few fine setae at posterior margin. S8 dark, distinctly narrower than T8, finely setulose, posteromedially strongly projecting and with narrow mediodorsal incision as usual. T10 small, moderate in length, dark and bare except for sparse microtomentum at indistinct posterior margin and with a pair posteromedial setae. S10 paler and slightly larger than T10, roughly pentagonal, micropubescent, with longer setulae at posterior margin. Internal sclerotisation of genital chamber composed of distinctly pigmented, flat but crooked posterior sclerites (two partly fused), medial double finely ribbon-like structure (see Fig. 96 ) and of transverse, strongly twisted, unpigmented anterior ringshaped structure (not figured but similar to that of A. undulatus sp.n. —cf. Fig. 107 ). Genital opening surrounded by fine dense spines. Ventral receptacle ( Fig. 95 ) membranous, formed by clavate pouch on proximal tube and vermicular, strongly twisted terminal projection. Spermathecae (1+1), spherical, one distinctly larger than the other ( Fig. 98 ), each with fine blunt spines inserted on basal third of spermatheca; duct cervix well developed, relatively long. Cerci smaller and more slender than in A. undulatus sp.n., with moderate setosity.

Discussion: A. sparsus sp.n. forms together with A. obscurior sp.n., A. undulatus sp.n. and A. poecilus sp.n. a species group characterised by similar wing pattern and strongly sinuous veins R 2+3 and R 4+5. However, it most resembles its closest relative, A. undulatus sp.n., both in external features and male and female genitalia. This sister-pair is defined by several synapomorphies, eg. posteroventrally projecting postgonite, unarmed basal membrane, apex of saccus of distiphallus densely finely spinose, narrow and medially unpigmented female S7. The differences between these species are stressed under A. undulatus sp.n. below.

Biology: Type specimens were collected in January, April and November.

Distribution: Ivory Coast, Cameroon, Uganda.

Figures

Figs 88–93. Amygdalops sparsus sp.n., male paratype (Uganda). 88. External genitalia, caudal view. 89. Same, lateral view. 90. Hypandrium and associated structures, lateral view. 91. Gonostylus, sublateral view (widest extension). 92. Hypandrium and associated structures, ventral view. 93. Aedeagal complex, lateral view. Scales = 0.1 mm.

Figs 94–98. Amygdalops sparsus sp.n., female paratype (Uganda). 94. Postabdomen + 5th segment, dorsal view. 95. Ventral receptacle, lateral view. 96. Internal sclerites and S8, ventral view. 97. Postabdomen + 5th segment, ventral view. 98. Spermathecae. Scales: Figs 94, 97 = 0.1 mm, others = 0.05 mm. For abbreviations see text.

Figs 129–132. Wings of Amygdalops species. 129. A. obscurior sp.n., male paratype (Uganda). 130. A. sparsus sp.n., male paratype (Uganda). 131. A. undulatus sp.n., male paratype (Madagascar). 132. A. poecilus sp.n., female paratype (South Africa). Scales = 0.5 mm.

Figs 104–109. Amygdalops undulatus sp.n., male and female paratypes (Madagascar). 104. Hypandrium and associated structures, lateral view. 105. Postabdomen, dorsal view. 106. Ventral receptacle, lateral view. 107. Internal sclerites, ventral view. 108. Postabdomen + 5th segment, ventral view. 109. Spermatheca. Scales: Figs 104, 105, 108 = 0.1 mm, others = 0.05 mm. For abbreviations see text.