Doesburgella, Rédei, Dávid & Jindra, Zdeněk, 2013

Rédei, Dávid & Jindra, Zdeněk, 2013, A new genus and species of ambush bugs from South Africa (Hemiptera: Heteroptera: Reduviidae: Phymatinae), Zootaxa 3721 (1), pp. 79-84 : 79-84

Doesburgella , gen. nov.

Type species by present designation: Doesburgella dilatata , sp. nov.

Diagnosis. The new genus can be recognized within the tribe Macrocephalini by the following combination of characters: scutellum reaching apex of corium; each humeral angle provided with a large, dorsolaterally directed, wing-like projection; abdomen much broader than long. Characters apparently unique in Doesburgella gen. nov. are the broadly dilated abdomen and the distinctive scutellum (with a pair of submedian denticles apically). For a more detailed comparison with related genera see Discussion.

Description. Macropterous female. General facies ( Figs. 1–2 ) as typical in Macrocephalinae , elongate; humeri produced into a pair of wing-like projections; abdomen conspicuously dilated.

Integument and vestiture. Integument dull; head, antenna, and anterior lobe of pronotum granulate; disk of posterior lobe of pronotum rather coarsely and sparsely punctate; lateral margin of anterior lobe of pronotum coarsely, that of posterior lobe finely crenulate; proepisternum and pterothoracic pleuron granulate, proepimeron and epimeroid (sensu Štys & Baňař 2013) punctate; scutellum and corium finely punctate; abdomen finely, inconspicuously granulate dorsally and ventrally. Body glabrous except of minute, adpressed dark hairs on apical fourth of antennal segment IV, sensory hairs on fore femur and tibia, fine, adpressed pilosity on proximal portions of femur and tibia of fore leg, and the usual fine pilosity on distal portions of tibiae and ventral surfaces of tarsi of mid and hind legs.

Head (Figs. 3–4) parallel-sided in dorsal view; preocular and postocular portions subequal in length; antennal sclerite strongly produced anteriad, flattened, surrounding antennal socket laterally (Figs. 3–6); mandibular plate reduced; maxillary plate produced anteriad, surpassing apex of antennal sclerite and gena; genae forming a pair of short flanges (bucculae) adjacent along midline, continued in a pair of subparallel, posteriorly separate carinae approaching but not reaching base of gula proximally, with strongly and irregularly denticulate ventral margin, interspace between the carinae subequal to diameter of first apparent labial segment; labrum small, visible posteriad of adjacent anteromedian portions of genae; eyes relatively small, weakly protruding laterally; ocelli small, situated slightly anteriad of middle of postocular portion; vertex between ocelli flat.

FIGURES 3–9. Doesburgella dilatata gen. et sp. nov., female holotype. 3, head and prothorax, lateral view; 4, head and anterior part of prothorax, ventral view; 5, right antenna, dorsal view; 6, same, segments I–III in lateral view 7, right half of pronotum, dorsal view; 8, right fore trochanter, femur and tibia, median surface; 9, apex of abdomen of female, posteroventral view. Lettering: gpc = gonoplac; t8 = dorsal portion of tergite VIII; t8' = ventralized posterior portion of tergite VIII; t9 = tergite IX; vf8 = valvifer VIII. Scales in mm.

Antenna (Figs. 5–6) robust; segment I thick, short, less than twice as long as its greatest diameter, dorsal margin of its apex produced above insertion of segment II; segment II as long as wide, articulated to ventrolateral surface of apex of segment I; segment III minute, distinctly shorter than wide; segment IV longest and thickest. Labium with first apparent segment robust, second much shorter and slightly narrower, third minute, narrow.

Prothorax. Pronotum (Figs. 4, 7) trapezoid; subdivided into anterior and posterior lobes by a distinct transverse furrow; anterior margin concave; anterior lobe distinctly shorter than posterior lobe, provided with a fine median longitudinal furrow reaching transverse furrow posteriorly; lateral margin weakly concave anteriad of humeral projections; with a pair of strong carinae from posterior portion of anterior lobe to middle of posterior lobe, slightly diverging posteriorly; disk of posterior lobe with a broad median longitudinal furrow not reaching posterior margin; each humeral angle provided with a large, dorsolaterally directed, wing-like projection; posterolateral angle obtusely produced, associated with a relatively small tumescence at posterolateral portion of disk; posterior margin distinctly, angularly convex. Anterior margin of propleuron concave, anteroventral portion projecting anteriad (Fig. 4).

Pterothorax. Scutellum distinctly shorter than abdomen, reaching apex of corium and base of abdominal tergite VI, with nearly straight lateral margins gradually tapering towards apex; apex of scutellum rounded, provided with a pair of conspicuous submedian denticles. Fore wing: coriaceous portion narrowly visible in rest, apex of corium distinctly tapering to a point, veins Sc (forming anterior [= lateral] margin), R+M and Cu somewhat thickened; membrane reaching apex of abdomen, membranal portion of R bifurcate, M simple, Cu and AA1+2 connected by a cross-vein. Mesosternum long, with a pair of two adjacent, deep longitudinal sulci to accommodate the anterior coxae in rest, separated by a narrow, basally thickened median longitudinal carina. Metasternum very short.

Legs. Fore leg (Fig. 8) with coxa gradually thickened towards apex, broadest about 75% of its total length, distinctly constricted subapically; trochanter without peculiarities; femur much longer than coxa, distal half dilated with ventral margin rounded and flattened, dilated distal portion with a proximal conical process provided with a minute spine at its apex, with two series of minute black spines marginally along its whole length, and 5–6 sensory setae submarginally; tibia strongly curved, gradually narrowed towards apex, apically pointed; ventral surface with a series of minute black spines posteriorly (= at its outer side) and a series of 6 sensory setae anteriorly (= at its inner side). Mid and hind legs short, femur of mid leg distinctly shorter than that of hind leg, mid tibia about 3/4, hind tibia about 2/3 length of femora of the respective legs; tarsi of mid and hind legs subequal in length to the respective tibiae, 2-segmented, segment I very short, segment II elongate, curved.

Abdomen strongly dilated, rhomboidal, much broader than long, with greatest width between posterolateral angles of segment IV ( Figs. 1–2 ); laterotergites distinctly more narrow than portions of mediotergites exposed from fore wings in rest; ventral surface of segments II–VII margined by reflexed marginal portions of the respective laterotergites; laterosternites broad; mediosternites III–VI each with a ˄-shaped carina medially, each bordered by a pair of posteriorly diverging oblique carinae ( Fig. 2 ); spiracles II–VII situated on lateral portions of the respective mediosternites; tergite VIII subdivided to a dorsal (Fig. 9: t8) and a ventralized (Fig. 9: t8') portion, dorsal portion feebly emarginate posteriorly, ventralized portion transverse.

Males unknown.

Diversity and distribution. The genus is currently monotypic, the single included species occurs in South Africa.

Etymology. The new genus is named after and dedicated to Pieter H. van Doesburg, Jr., in recognition of his contribution to the taxonomy of various groups of Heteroptera , particularly Phymatinae . Gender feminine.

Doesburgella dilatata , sp. nov. ( Figs. 1 –9)

Type material. Holotype (♀): South Africa, Eastern Cape, Alexandria—Woody Cape, 10–13.xii.1997, leg. I. Jeniš; mounted on card, intact; in Zdeněk Jindra’s private collection currently deposited at the Department of Plant Protection, Czech University of Agriculture, Prague ( Figs. 1–2 ).

Description. Macropterous female. Colour. Ground colour ochraceous; head brownish ochraceous dorsad of level of eye, pale ochraceous ventrad of level of eye, postocular portions with a pair of longitudinal vittae dorsolaterally and with a transverse fascia along its basal margin connecting basal extremities of longitudinal fasciae black; antennal segments I–III dark brown, segment IV pale yellowish; labium pale ochraceous; pronotum ochraceous, posterior portions of submedian carinae brownish, humeral projections reddish brown; thoracic pleuron and sternum pale ochraceous, metapleurite with a large, rounded brown patch at middle; scutellum ochraceous, apical submedian denticles whitish; coriaceous portions of fore wings exposed in rest reddish brown with slight grayish suffusion, membrane smoky brown; abdomen ochraceous dorsally and ventrally, midline of ventral surface broadly paler; legs ochraceous, mid and hind tarsi ochraceous dorsally, dark brown ventrally.

Integument and vestiture. Antenna with densely distributed, small, whitish granulae; dorsum of head with minute, inconspicuous granulae, larger, distinct and conspicuous granulae present on lateral surface of head and along basal margin dorsally; anterior lobe of pronotum with distinct, conspicuous granulae, proepisternum and its anteroventral projection granulate, lateral margin of anterior lobe of pronotum and basal portions of submedian carinae with large, nearly denticle-like granulae; disk of posterior lobe of pronotum with rather coarse and sparse punctation, diameter of punctures and their interspaces variable; lateral margin of posterior lobe (including humeral projections) finely denticulate; proepimeron and epimeroid (sensu Štys & Baňař 2013) punctate; anterior portion of mesopleurite and whole of metapleurite with large, coarse, tubercle-like granules; scutellum finely punctate except of lateral margin of basal half, punctures become more superficial towards apex; corium finely and irregularly punctate; abdomen finely, inconspicuously granulate dorsally and ventrally, with larger granulae mainly on sternites III–VII submedially.

Head (Figs. 3–4) about 1.9 times longer (from base to apices of maxillary plates) than its width across eyes, about 1.7 times as broad across eyes as interocular distance. Antenna (Figs. 5–6): segment I about 1.65 times longer than its greatest diameter; segment IV about 3.2 times as long as its greatest diameter, gradually broadened to its distal third, then abruptly narrowed towards apex. Labium with apparent first segment about 1.8 times longer than apparent second segment.

Prothorax. Pronotum (Figs. 4, 7) about 1.7 times as broad between apices of humeral projections as its median length; posterior lobe about 1.55 times as long as anterior lobe; humeral projections large, dorsolaterally directed, with rounded anterior margin, a rather sharp lateral angle, and a small, semicircular posterolateral projection; humeral projection dorsally provided with a thick, nearly transverse carina running to sharp lateral angle, and another similar carina on its ventral surface (on epimeroid). Anteroventral projections of propleuron obtuse, short. Scutellum about 1.45 times as long as its greatest width (at its base), with lateral margin slightly thickened at its basal half.

Legs. Fore coxa about 3.4 times as long as its greatest diameter (at about 75% of its total length), distinctly constricted subapically; trochanter without peculiarities; femur (Fig. 8) about 1.35 times as long as coxa, about 3 times as long as its greatest diameter, posteroventral series composed of about 65, anteroventral series of about 37 spines; tibia (Fig. 8) about 6.5 times as long as its greatest diameter (subbasally), ventral surface with about 50 spines.

Abdomen about 1.6 times as broad as its median length (measured in ventral view from base of sternite II). Female terminalia (Fig. 9). Tergite IX (Fig. 9: t9) elongate, gradually narrowed posteriorly; valvifers VIII (Fig. 9: vf8) large, with inner margin S-shaped, gonoplac (= individualized apical portion of valvifer IX) (Fig. 9: gpc) small, posteriorly rounded.

Measurements (in mm). Total length 11.2; length of head (in dorsal view from base to apices of maxillary plates) 2.18, width across eyes 1.13, interocular distance 0.66, interocellar distance 0.52; lengths (greatest diameters) of antennal segments I–IV as 0.63 (0.38): 0.28 (0.28): 0.21 (0.22): 1.78 (0.56); lengths of first, second and third apparent labial segments as 1.23: 0.68: 0.24; median length of pronotum 3.08, of anterior lobe 1.20, of posterior lobe 1.88, width across anterior angles 1.13, across apices of humeral projections 5.25; median length of scutellum 3.65, greatest width 2.50; length (greatest diameter) of fore coxa 2.03 (0.59), of fore femur 2.75 (0.93), or fore tibia 1.63 (0.25); greatest width of abdomen 8.25.

Male unknown.

Distribution. South Africa: Eastern Cape Province.

Etymology. The specific epithet of the new species is formed from the Latin adjective dilatatus, - a, - um ‘dilated, widened’ referring to its broadened humeri and abdomen.

Discussion

Afrotropical genera of the tribe Macrocephalini were keyed by Kormilev (1984) and Doesburg (2004), world genera by Froeschner & Kormilev (1989). The seven genera occurring in the Afrotropical Region can be distinguished from Doesburgella gen. nov. by the following characters:

Paragreuocoris Carayon, 1949 and Metagreuocoris Villiers, 1965 (both from Central Africa) conspicuously differ from Doesburgella gen. nov. in having a greatly elongate scutellum reaching or almost reaching apex of abdomen (Carayon 1949, Villiers 1965).

Oxythyreus Westwood, 1841 and Goellneriana Doesburg, 2004 (both from South Africa) differ from the new genus in the nearly straight or weakly convex lateral margin of the posterior lobe of the pronotum and the simple, short, laterally directed humeral projections (Doesburg 2004).

Doesburgella gen. nov. shares most diagnostic characters with the South African genera Eurymnus Bergroth, 1917, Narina Distant, 1906 and Parabotha Kormilev, 1984. Of these, Eurymnus is more or less similar to the new genus in the shape of the humeral projection and in the broadly dilated abdomen, but (together with Oxythyreus ) it differs in having a much shorter scutellum (apex not reaching apex of corium) gradually tapering towards apex. The fore wing venation of Eurymnus is also much different from that of Doesburgella gen. nov. (cf. Kormilev 1984). Parabotha and Narina are similar to the new genus in the length of the scutellum (reaching to apex of corium and base of abdominal tergite VI) and in the fore wing venation, but both of them differ in the shape of the pronotum (humeri rounded and directed obliquely forward) (Kormilev 1984). In all of the genera discussed above, just like in all other genera of Macrocephalini , the abdomen is elongate, distinctly longer than its greatest width.

Acknowledgements

We are grateful to Petr Kment (National Museum, Prague) and an anonymous reviewer for helpful comments on the manuscript.

Figures

FIGURES 1 – 2. Doesburgella dilatata gen. et sp. nov., female holotype. 1, dorsal view; 2, ventral view.