Amygdalops poecilus, 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 : 207-212

Amygdalops poecilus sp. n.

( Figs 110–121 , 132 )

Type material: Holotype male, labelled: ‘ Dhlinza Forest , Eshowe, Zululand, South Africa. B. & P. Stuckenberg, 5–6. April 1960 ’ ( NMSA, genit. prep.) . Paratypes: SOUTH AFRICA: Natal , Pietermaritzburg, Town Bush, 9.vi.1979, 1 female, R. Miller leg. ( NMSA, genit. prep.) . ZAIRE (REPUBLIC CONGO): Parc National Albert , Mont Hoyo, 1280 m, sur plantes bases, 7–15.vii.1955, 1 male 7 females, P. Vanschuytbroeck leg. ( MRAC, SMOC, genit. prep.); Mont Hoyo, grotte Ikonongi, 1215 m, 9.viii.1955, 1 female, P. Vanschuytbroeck leg. ( MRAC, genit. prep.); Parc National Albert, Secteur Tshiaberimu, Riv. Mbulikerere, affl. dr. Talia N, 2720 m, 26–28.viii.1953, 1 male, P. Vanschuytbroeck & V. Hendrickx leg. ( MRAC, genit. prep.). Most specimens from Zaire more or less damaged .

Etymology: The species is named ‘poecilus’ (= Greek variegated) owing to its variegated wing.

Description: Male.

Total body length 1.98–2.50 mm; bicolorous, dark brown and yellow.

Head: Somewhat higher than long. Occiput dark brown, with some silvery grey microtomentum in medial concavity. Frons dark brown, only anterior fourth ochreous to yellow. Frontal triangle narrow, reaching to anterior third of frons and shiny including ocellar triangle; also orbit shiny to subshiny, only darker microtomentose stripes between orbits and frontal triangle dull. Face very narrow, ochreous-yellow; parafacialia, gena and postgena yellowish white with silvery white microtomentum. Ventral margin of gena brownish as are also dorsal mouthparts and palpus; ventral mouthparts orange. Cephalic chaetotaxy: pvt small but strongly crossed; vti shorter than vte but relatively long, longer and stronger than oc; vte longest of cephalic setae; 2 long ors (posterior almost as long as vte, anterior distinctly shorter) and 2 usual microsetulae in front of anterior ors; 1–2 pairs of very minute setulae medially in front of frontal triangle; 1 long vi and 1 shorter subvibrissa (about two-thirds of vi); peristomal setulae short except for the foremost one; postocular setulae minute; preapical seta on palpus distinct. Eye with longest diameter 1.4 times as long as shortest one. Gena very narrow; its smallest height 0.08 times as long as shortest eye diameter. Antenna orange yellow, 1st flagellomere somewhat darker, particularly on inner side and around base of arista. Arista 1.95 times as long as antenna, long pectinate, particularly dorsobasally.

Thorax: Narrower than head, brown to dark brown and yellow. Pronotum, mesonotum (including scutellum and notopleural areas) and dorsal part of pleura up to ventral portion of mesopleura brown to dark brown; rest of pleura yellow; thus, the dark dorsal pleural band wider than in all congeners. Thoracic chaetotaxy: 1 small prs; 2 dc, posterior very long and as long as apical sc, anterior very reduced, as in A. sparsus sp.n.; 2 sc, laterobasal small, slightly longer than anterior dc; 1 ppl, usually indistinct; 2 stpl, anterior weak, posterior longer and thicker; ventral sternopleural setae few and weak. Scutellum slightly convex dorsally. Legs completely yellow in South African specimens but with brown distal thirds to two-fifths of f 2 and f 3 in specimens from equatorial Africa. Chaetotaxy of legs as in A. sparsus sp.n., including shortened setae in posteroventral row on f 3. Wing ( Fig. 132 ) with distinctive pattern and venation characterised 3 rounded, white, iridescent spots (between R 2+3 and R 4+ 5 in front of terminal dark spot, between R 4+5 and M in distal third of wing and between M and wing margin behind dm-cu cross-vein) and by very strongly sinuous R 2+3, R 4+5 and M. Discal (dm) cell relatively long, with r-m situted in front of its middle. A 1 very short. Wing measurements: length 2.18–2.58 mm; width 0.59–0.75 mm, Cs 3: Cs 4 = 2.21–2.30, r-m\dm-cu: dm-cu = 2.83–3.46. Haltere with yellowish white stem and blackish brown knob.

Abdomen: With large, dark brown preabdominal terga and small, paler brown preabdominal sterna. T6 short, transverse, weakly sclerotised and pale ochreous. Preabdominal sterna narrow, S2–S4 distinctly longer than broad (in specimens from Zaire markedly narrower than in those from South Africa); S5 large, wider than S4, with posterior emargination. S6–S8 blackish brown, dorsolaterally fused; S6 ventrally very short and projecting on right side of abdomen.

Genitalia: Epandrium hemispherical, medium-long ( Figs 110, 111 ), setose in posterior half; setae moderate, 1 dorsomedial pair longer than others; anal opening narrow but high, rounded pentagonal ( Fig. 110 ). Cercus moderate, finely setose. Medandrium ( Fig. 110 ) comparatively high, with projecting dorsolateral corners. Gonostylus ( Fig. 115 ) elongately subtriangular (in widest extension view), strongly tapered in distal half, more slender than in A. sparsus sp.n or A. undulatus sp.n. with apex bent anteriorly but not very acute; micropubescence covering most of proximal half of outer side, distal half with only a few microsetulae; inner side with long setae, particularly at anterior margin. Hypandrium ( Fig. 112 ) relatively short and high in proximal half, with membranous internal lobes; transandrium ( Fig. 113 ) only medially slender, with deep ventral incision; caudal process formed by unpaired medial band-like sclerite being attached to transandrium by its tapered dorsal tip. Pregonite ( Fig. 112 ) fused with hypandrium, incurved but somewhat protruding ventrally, with 2 groups of setae, each enumerating about 4 setae, those on posteroventral bulge longer. Postgonite ( Fig. 112 ) short, dark, of very peculiar shape, with proximal bulge carrying a setula, large anterior tooth in the middle and shortly bicuspidate apex; basal sclerite attached to postgonite also unusual, large, with a long slender ventral projection (as long as postgonite) and also dorsally tapered, and with finely granulose surface. Aedeagal part of folding apparatus ( Fig. 114 ) unusually reduced, membranous with only very weak tubercles dorsally and fine setulae or spinulae ventrally; connecting sclerite very short, pale, and finely granulose. Basal membrane ( Fig. 113 ) finely spinulose dorsally and armed by a cluster of robust thorn-like tubercles ventrally. Aedeagal complex ( Fig. 114 ) weak, with slender phallapodeme, having besides usual bifurcate base a pair of flat lateral wing-shaped processes in the middle. Aedeagus with small (as long as high) phallophore, and distiphallus, which is strikingly smaller than in all relatives. Base of distiphallus bare, with darker ventral margin. Saccus of distiphallus unusualy small, except for sclerotised base membranous and armed by dense spines restricted to its distal third. Filum of distiphallus also surprisingly short, only slightly sinuous and formed by 2 dark, basally broad, apically very slender stripe-like sclerites terminating into dilated but membranous apex having somewhat dentate margin. Ejacapodeme small, with rather short digitiform projection.

Female differs from male as follows:

Total body length 2.38–3.14 mm.

Face, dorsal mouthparts and palpus darker than in male. f 3 posteroventrally simply setulose. Wing measurements: length 2.58–2.86 mm, width 0.71–0.83 mm, Cs 3: Cs 4 = 2.08–2.54, r-m\dm-cu: dm-cu = 2.60–2.94.Abdomen with preabdominal terga shorter and more transverse, all dark brown. Preabdominal sterna narrow, longer than broad, somewhat paler brown than terga, distinctly lighter than S6 (again, S2–S 5 in specimens from Zaire markedly narrower than those of South African specimens).

Postabdomen ( Figs 116, 120 ) relatively slender and entire dark brown pigmented. T6 relatively narrow, tapered posteriorly, densely shortly setose. S6 dark and narrower than T7 (it is only slightly wider than S 5 in South African female but distinctly wider than S 5 in females from Zaire). T7 dark brown, narrow, anteriorly emarginate, laterally reaching on ventral side of abdomen, with anteroventral corners almost meeting with anterior part of S7. S7 slender, elongate, with sinuous lateral margin and characteristic dark pattern composed of a pair of small anterior rounded spots and a large one covering posterior setose half of sclerite ( Fig. 120 ). T8 relatively large and long in contrast to relatives, plate-shaped, with a few fine setae in posterior rounded corners. S8 dark, very slightly narrower than T8, finely setulose, posteromedially strongly projecting and with narrow mediodorsal incision as usual. T10 small, moderate in length, with dark laterobasal spots, sparse microtomentum restricted to medial area and with a pair of medial setae. S10 larger (particularly longer) than T10, roughly pentagonal, micropubescent, with longer setulae at posterior margin. Internal sclerotisation of genital chamber (see Fig. 119 ) composed of very pale pigmented, crooked posterior sclerites (two partly fused), medial double fine ribbon-like structure and transverse, twisted, unpigmented (poorly visible) fine anterior ring-shaped structure close to posterior sclerites. Genital opening surrounded by fine dense spines. Ventral receptacle ( Fig. 118 ) membranous, formed by elongate subclavate tube and digitiform, anteroventrally directed projection. Spermathecae 1+1 ( Figs 117, 121 ), spherical, each with very short blunt spines inserted on basal third of spermatheca; duct cervix well developed, long and distinctly ringed in place of its connection with membranous duct. Cerci moderate, medium-long setose.

Discussion: The new species differs markedly from all relatives in having three rounded white spots on wing, strongly sinuous M in addition to R 2+3 and R 4+5 and very peculiar male genitalia. Although its gonostylus resembles those of other species of the A. sparsus group, its internal genitalia are essentially different (cf. peculiar postgonite and its basal sclerite, (secondarily) unpaired caudal process, reduced aedeagal part of folding apparatus, reduced distiphallus with very short filum, wing-like processes in the middle of the phallapodeme). The female is characterised mainly by dark but very narrow sterna (S2–S6) and distinctive pigmentation of S7.

The specimens from Zaire display some differences against those from South Africa (the type locality) in having brown annulate distal parts of mid and hind femora and narrower and darker preabdominal sterna of both sexes. It is possible, that the two populations represent different taxa, but more material (also from intervening areas) is necessary to demonstrate this hypothesis.

Biology: Adults were collected in April, and June to August. Specimens from Zaire were caught on low vegetation.

Distribution: South Africa, Zaire (Republic Congo).

Figures

Figs 110–115. Amygdalops poecilus sp.n., male holotype. 110. External genitalia, caudal view. 111. Same, lateral view. 112. Hypandrium and associated structures, lateral view. 113. Transandrium, caudal view. 114. Aedeagal complex, lateral view. 115. Gonostylus, sublateral view (widest extension). Scales: Fig. 115 = 0.05 mm, others = 0.1 mm. For abbreviations see text.

Figs 116–121. Amygdalops poecilus sp.n., female paratype (South Africa). 116. Postabdomen, dorsal view. 117. Spermatheca. 118. Ventral receptacle, lateral view. 119. Internal sclerites, ventral view. 120. Postabdomen, ventral view. 121. Spermatheca. Scales: Figs 116, 120 = 0.1 mm, others = 0.05 mm.

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.