Dichelocentrum longirostre ( Reuter, 1905 ) Gapon, D. A., 2014

Gapon, D. A., 2014, Revision of the genus Polymerus (Heteroptera: Miridae) in the Eastern Hemisphere. Part 1: Subgenera Polymerus, Pachycentrum subgen. nov. and new genus Dichelocentrum gen. nov., Zootaxa 3787 (1), pp. 1-87 : 73-78

1. Dichelocentrum longirostre ( Reuter, 1905) comb. nov.

( Figs 5 C ; 13 F ; 33 A ; 34 A–H ; 36 D, I, J ; 38 , A, B; 42 , A, B)

Poeciloscytus longirostris Reuter, 1905: 14 .

Polymerus longirostris Carvalho, 1959: 237 .

Polymerus (Poeciloscytus) longirostris, Odhiambo, 1959: 37 .

Material examined. Syntype: “Levander”, “Massauah”, “ Poeciloscytus longirostris n.sp. O.M. Reuter det.”, male* ( MZHF) .

Additional material. Tanzania, Mlingano , 2 Feb.1964, I.A.D. Robertson, 6 males *, 3 females * ( AMNH) .

Diagnosis. Distinguished by yellowish-brown first antennal segment, rarely with small isolated dark spot at base, yellowish-brown femora without dark spots. Male recognised by right paramere with short and tapering hypophysis on lateral view and small smooth tubercle on anterior wall under it; long hypophysis of left paramere with convex superior and inferior margins before apex on lateral view; posterior right lobe of inflated vesica with straight right branch and very short left branch, perpendicular to the latter. The described form of parameres does not occurs among other Dichelocentrum species except for D. flora ( Linnavuori & van Harten, 2005) comb. nov., but it has reddish femora, first two antennal segments, cuneus and venter of abdomen. Some specimens of D. ornatifrons (Odhiambo, 1959) comb. nov. can be similar to D. longirostre in a colouration but clearly distinguished from the latter by the shape of parameres and vesica.

Redescription. Length 4.10–4.30 in males and 4.75–5.25 in females. Body covered with goldish or silvery thickened setae ( Fig. 40 A, B ).

Dorsal surface of head dark brown or blackish. First and second antennal segments brownish-yellow; first segment rarely with small dark spot at base on external side; second segment in apical third dark brown; third segment dark, with paler base. Rostrum yellow, with brown apex, more or less protrude behind hind coxae.

Pronotum dark brown, sometimes blackish, except yellow collar, rather wide strip on posterior margin and narrower medial strip. The latter often more or less shortened to a small triangular spot in middle of transverse strip. Triangular spots at ends of transverse strip relatively large. Scutellum blackish-brown in basal part, its apex with large longitudinal pale spot. Often scutellum completely pale except its base and lateral margins in basal part. Clavus dark brown to blackish. Corium dirty yellow and light or dark brown in its posterior and interior part. Cuneus light brown, lighter in its interior part and darker in external part; its base with pale stripe extending mediad, extreme apex pale. Membrane fuliginous, with yellow veins. Venter of body brownish-yellow or light brown. Sometimes pleurites are rather dark. Evaporatorium whitish. Legs brownish-yellow.

Right paramere ( Fig. 34 A, B, E, F ). Hypophysis short, with pointed apex. Anterior wall of paramere body with small tubercle just under hypophysis.

Left paramere ( Fig. 34 C, D, G, H ) slightly longer than right one. Hypophysis long, its superior and inferior margins from lateral view convex in distal part, concave before apex; inferior margin concave stronger than superior one. Carina on internal (right) wall of hypophysis relatively high (on posterior view), with several very short setae.

Vesica ( Figs 5 C ; 36 D, I, J ). Anterior branch of anterior right lobe rather long, tapering apically; right and inferior bladders rather small and smooth. Superior branch of anterior left lobe curved posteriad; inferior branch very short, conical, directed to left and slightly posteriad. Posterior left lobe with smooth basal tubercle and with sclerotised triangular area on anterior wall. Superior branch of anterior left lobe touches this sclerotised area. Posterior right lobe straight, directed anteriad and slightly downwards. Its right branch rather long, wide, with rounded apex, directed slightly to right. Left branch very short and looks like narrow conical tubercle, directed to left. Superior margin of posterior branch of spicule smoothly curved in apical part from posterior view in wet preparations ( Fig. 36 D ).

Gynatrium ( Fig. 38 A, B ). Notch on ventral margin of interramal sclerite arcuate, shallow. Small separated longitudinal sclerite usually lies near middle of dorsal margin of interramal sclerite and reaches or almost reaches dorsal margin of posterior wall of gynatrium.

Taxonomic notes. Linnavuori (1977) in his description of D. longirostre mentioned its orangish first antennal segment, orangish or reddish femora and yellow with distinct reddish tinge ventral surface of the body. The specimens of this species studied by me do not have orangish or reddish tinges in the colouration. Perhaps Linnavuori’s specimens partially belong to D. flora that is closest to D. longirostre .

Distribution. Sudan, Eritrea, Kenya, Somalia. New record for Tanzania.

Figures

FIGURE 5. Structure of theca. A, theca of Polymerus nigrita; B, theca of Dichelocentrum longirostre; C, apical blade of theca of Dichelocentrum longirostre; D, apical blade of theca of Charagochilus gyllenhalii. Anterior (A, B) and anterio-inferior view (C, D). Scale bare: 0.14 mm.

FIGURE 13. Secondary gonopore. A, Polymerus (Pachycentrum) nigrita; B, P. (Poeciloscytus) unifasciatus; C, Charagochilus gyllenhalii; D, Proboscidocoris fuliginosus; E, Pr. nitidus; F, Dichelocentrum longirostre. lsc—left serrate carina; sgp—subgonoporal plate.

FIGURE 33. Antennae. A–E, first antennal segment; F–H, antennae totally. A, Dichelocentrum longirostre comb. nov., syntype; B, D. ornatifrons comb. nov. from Tanzania; C, holotype of Polymerus xerophilus; D, D. ornatifrons, male paratype; E, D. ornatifrons, female paratype; F, Polymerus carpathicus, male; G, D. transvaalicum sp. nov., female; H, D. transvaalicum, male. Scale bare: 0.14 mm.

FIGURE 34. Parameres of Dichelocentrum gen. nov. species. Right (A, B, E, F, I, J) and left (C, D, G, H, K, L) parameres. A–D, D. longirostre comb. nov., syntype; E–H, D. longirostre comb. nov. from Tanzania; I–L, D. flora comb. nov. Right (A, E, I), left (C, G, K) and posterior (B, D, F, H, J, L) view. Scale bare: 0.14 mm.

FIGURE 36. Vesica of Dichelocentrum gen. nov. A–C, uninflated vesica; D–H, anterior spicule; I–K, inflated vesica. A, D. flora comb. nov., holotype; B, D. ornatifrons comb. nov., paratype; C, D. alkadanum comb. nov., paratype after Linnavuori & van Harten (2005); D, D. longirostre comb. nov., syntype; E, D. flora, holotype; F, D. flora from Niger; G, D. ornatifrons, paratype; H, D. alkadanum, paratype after Linnavuori & van Harten (2005); I, J, D. longirostre; K, D. flora. Left (A–C, I), posterior (D–H), and superior (J, K) view. all—anterior left lobe; arl—anterior right lobe; as—anterior spicule; pa—posterior apex of vesica; pb.bab—posterior branch of basoapical sclerotised band; pll—posterior left lobe; prl—posterior right lobe; sg—secondary gonopore. Scale bare: 0.14 mm.

FIGURE 38. Inner female genitalia of Dichelocentrum gen. nov. A, gynatrium in dorsal view; B, C, posterior wall of gynatrium in ventral view. A, B, D. longirostre comb. nov., syntype; C, D. ornatifrons comb. nov. mpr—medial process; ihf—posterior margin of inner horizontal fold; ts—tectal sclerites.. Scale bare: 0.14 mm.

FIGURE 40. Polymerus species, habitus. A, P. (Pachycentrum) carpathicus, male; B, P. (Pachycentrum) nigrita, female; C, P. (Pachycentrum) unciniger sp. nov., male; D, P. (s. str.) holosericeus, female; E, P. (s. str.) russatus sp. nov., male; F, P. (s. str.) russatus sp. nov., female; G, P. (s. str.) pekinensis; H, holotype of Poeciloscytus funestus, male; I, paratype of Poeciloscytus funestus, female; J, Polymerus (s. str.) amurensis, female.

FIGURE 42. Dichelocentrum gen. nov., habitus. A, D. longirostre comb. nov., syntype, male; B, D. longirostre comb. nov., female; C, D. flora comb. nov., holotype, male; D, D. ornatifrons comb. nov., paratype, male; E, D. ornatifrons, paratype, female; F, holotype of Polymerus xerophilus, female; G, D. transvaalicum sp. nov., male; H, D. transvaalicum, female; I, D. alkadanum comb. nov., holotype, female.