Distantiella, CHINA, 1944

Namyatova, Anna A. & Cassis, Gerasimos, 2016, Systematic revision and phylogeny of the plant bug tribe Monaloniini (Insecta: Heteroptera: Miridae: Bryocorinae) of the world, Zoological Journal of the Linnean Society 176 (1), pp. 36-136 : 92-93

DISTANTIELLA CHINA

Figures 8, 14P–S, 18R, S, 23

Distantiella China, 1944: 188 (gen. nov.; type species Sahlbergella theobroma Distant, 1909 by original designation); China, 1944: 179 (key to gen.); Schouteden, 1945: 116 (note); Carvalho, 1952: 60 (cat.); Carvalho, 1955: 42 (key to gen.); Carvalho, 1957: 145 (cat.); Lavabre, 1977a: 50, 53 (key to gen., descr.); Lotode, 1977: 188 (ecol.); Schmitz, 1987: 1 (disc.); Schuh, 1995: 528 (cat.); Schuh, 2002 –2013 (cat.).

Diagnosis: Distantiella belongs to the Odoniella - complex (see discussion for the tribe), and it differs from other genera of this group by: apex of ASII distinctly swollen (fig. 8E in Namyatova et al., in press); and ASIII–IV distinctly clavate (fig. 8F in Namyatova et al., in press); scutellum triangular (as in Fig. 11J), divided into lower and upper parts (as in Fig. 12B); frons with undivided or bifurcated outgrowth (as in Fig. 10F, fig. 4C in Namyatova et al., in press); pronotum and scutellum punctuate, bearing tumescences ( Fig. 4C in Namyatova et al., in press); hemelytron with pale or dark flattened setae; hind tibiae densely setate with distinct tumescences.

Redescription: Male: Length 6–8.5 mm. COLORATION ( Fig. 8). Mostly dark brown with brown markings. TEXTURE. Tubercles on vertex indistinct; flattened areas on vertex more or less distinct; ASII and hind tibia with tumescence medially; pronotum and scutellum covered with distinct punctures, collar with paired tubercles at sides; tubercles on pronotum and scutellum present, upraised (as in Fig. 11J); row of punctures on clavus and on R + M and punctures on depression delimiting calli posteriorly absent; striations on lateral margins of scutellum indistinct or present only anteriorly; semicircular depression between scutellum and mesoscutum absent. VESTITURE. Head, pronotum and scutellum clothed mostly with short simple adpressed pale setae, sometimes very rare, sometimes setae on head and anterior part of pronotum flattened; thoracic pleura with simple or flattened adpressed pale setae; hemelytron mostly with pale or dark flattened setae, cuneus and often posterior margin of corium with simple adpressed setae; ASI with adpressed short pale simple setae, ASII–IV with simple pale or dark suberect setae, some of them spine-like, shorter than width of hind tibia; legs with very dense dark setae, shorter than width of hind tibia; abdomen often clothed with short pale adpressed setae; black spinules on femora and tibiae not clear because of the dense setation. STRUCTURE. Head. Distance between eye and pronotum shorter than eye diameter (as in Fig. 10F); occipital region not delimited with depression; longitudinal depression on vertex present, shorter than eye diameter; eye stylate, directed outwards, c. 0.15× as wide as head; distance between antennal fossa twice as long as antennal fossa width; frons distinctly swollen (as in Fig. 10F), with paired outgrowths (as in fig. 4C in Namyatova et al., in press), without longitudinal depression or ridges; anterior view of head c. 2.1× as wide as high; eye height as long as distance from eye to apex of clypeus; antennal fossa oval, its width c. 0.6× as long as eye height, not raised (as in fig. 3B in Namyatova et al., in press); inferior margin placed near inferior margin of eye; base of clypeus placed above inferior margin of eye, distinctly delimited basally; in lateral view head flat, gula shorter than buccula length, convex. Labium. Length reaching middle of metasternum; LSI c. 2× as long as wide; LSII c. 3× as long as wide, subequal to LSI; LSIII c. 3× as long as wide, subequal to LSII; LSIV c. 4× as long as wide, slightly longer than LSIII. Antenna. Slightly surpassing base of scutellum; ASI c. 1.5× as long as wide, subequal to quarter of head width, swollen basally (as in fig. 8E in Namyatova et al., in press); ASII c. 4× as long as ASI, c. 0.6× as long as head and pronotum combined, swollen apically; ASIII c. 0.6× as long as ASII, swollen apically; ASIV c. 0.8× as long as ASIII, clavate (as in fig. 8F in Namyatova et al., in press). Thorax. Collar not delimited posteriorly, flat (as in fig. 4C in Namyatova et al., in press); calli separated, flat (as in fig. 4C in Namyatova et al., in press); depression delimiting calli posteriorly absent; humeral angles of pronotum slightly dilated, not serrate (as in fig. 4C in Namyatova et al., in press); posterior margin of pronotum distinctly concave, forming right angles (as in Fig. 11J); scutellum swollen (as in Fig. 11J), not covering or rarely covering base of pronotum, triangular (as in Fig. 11J), divided into lower and upper parts (as in Fig. 12B), lower part obtuse apically, without outgrowth, ridge or longitudinal depression medially; metepimeron enlarged, c. 1.5× as long as wide, angulate (as in Fig. 13E); metasternum with medial projection to abdominal segment II (as in fig. 17A in Namyatova et al., in press). Hemelytron. Slightly tapering anteriorly; costal margins straight; claval commissure c. 0.2× as long as scutellum, straight; R + M distinct only anteriorly, sometimes also medially, not reaching posterior margin of corium; medial fracture strongly inclined towards midline (as in fig. 12E in Namyatova et al., in press); cuneus c. 1.5× as long as wide, c. 0.4× as long as pronotum, medial margin almost straight (as in Fig. 13B); corium without swelling posteriorly; membrane distinctly surpassing apex of cuneus, forming acute angle, c. 0.7× as long as pronotum; auxiliary vein absent or very short; distance from cell to apex of membrane subequal to cell. Legs. Forecoxae contiguous (as in fig. 17A in Namyatova et al., in press); femora almost not swollen apically, straight; foretibia shorter than head and pronotum combined; tibia with distinct tumescences; segment I of hind tarsus as long as segment II and shorter than segment III; claw broadly rounded, basal tooth on claw more or less concave. Genitalia ( Fig. 14R, S). Genital capsule slightly wider than long, without outgrowth, ventral wall not shortened anteriorly; left paramere r-shaped, twice as long as right paramere; phallobase sclerite of primary gonopore subtriangular, with anterior distinctly concave; without outgrowth(s); ductus seminis not sclerotized basally, with sclerotized ring around secondary gonopore, ductus seminis shorter than phallotheca with coils forming wide tube, attached to phallobase medially; sclerotized part of phallotheca narrow wider basally, rounded apically, occupying half of dorsal side, without ridge or outgrowth; endosoma with sclerotized areas.

Female: Length 7.5–8.5 mm. Coloration, surface, vestiture and structure as in male, but females slightly larger than males ( Fig. 8). Genitalia ( Fig. 18R, S). DLP with medial sclerotized circle, c. 4× as long as wide, also with sclerotization along posterior margin; two large areas of striations present, contiguous; lateral oviducts attached at middle of those striated areas, widely separated, placed near lateral margin and at a halfway of DLP; spermathecal gland placed posteriorly, medially or on left-hand side; posterior wall with small tubercles, without outgrowth or sclerotization; base of second valvula with distinct swelling; ventral wall membranous.

Distribution: Distributed in Tropical Africa ( Fig. 23).

Host plants: Distantiella is known to be a major pest of cocoa ( Entwistle, 1977). It is also known from some other species of Malvaceae and Citrus sp. ( Piart, 1977).