Mecistoscelis lansburyi Kim et Jung, 2018

Kim, Junggon, Roca-Cusachs, Marcos, Pham, Hong-Thai & Jung, Sunghoon, 2018, A new species of the genus Mecistoscelis Reuter from Vietnam (Hemiptera: Miridae: Mecistoscelini), with key to Mecistoscelis species, Zootaxa 4434 (2), pp. 396-400 : 397-399

Mecistoscelis lansburyi Kim et Jung sp. nov.

( Figures 1 , 2 )

Diagnosis. Recognized by larger body length more than 6 mm; posterior lobe of pronotum with bracket-shaped markings; hypophysis of left paramere straight, with sharp apex; right paramere with distinct three spines subapically; endosoma membranous with a total of three sclerites.

Description. Male: Body narrowly elongated, length 6.5–6.6. Coloration. Generally greenish brown. Head: almost greenish brown, posterior part with dark brown marking, sometimes frons with dark markings; clypeus reddish brown to brown; antennae almost dark brown; first segment pale brown except for dark apex; other segments dark brown; rostrum generally brown. Thorax: pronotum generally greenish brown with dark markings; posterior margin of pronotal collar with convex dark brown marking; posterior lobe of pronotum with one pair of dark bracket-shaped markings; scutellum greenish brown, outer margin darkened; hemelytra mostly hyaline with longitudinal dark line; clavus entirely dark brown; inner part of posterior corium dark brown; cuneus entirely hyaline; legs pale brown; apical part of femur darkened; tibia dark brown; tarsus dark brown. Abdomen: greenish brown.

Surface and Vestiture. Body glossy, covered with sparse pubescence; pronotum glossy, rough; scutellum and hemelytra glabrous; hemelytron with distinct punctures.

Structure. Head: distinctly prognathous laterally; vertex with longitudinal sulcus, vertex width shorter than head length; compound eye shorter than vertex width, reaching to anterior margin of pronotum, ventral margin of compound eye not close to ventral suture of maxillary plate; antennae longer than length of body; first antennal segment cylindrical, thicker than other segments, shorter than second segment; third segment longer than fourth segment; proportion of first to fourth antennal segments 2.0: 3.4: 7.2: 2.8; labrum as long as first labial segment; labium reaching to hind coxae; proportion of first to fourth labial segments 0.7: 0.7: 0.3: 0.6. Thorax: pronotum trapezoid, mesal longitudinal length of pronotum as long as basal width; suture of pronotal collar obsolete, mesal length longer than width of first antennal segment; calli distinctly swollen; scutellum small, anterior width as long as 1/2 basal pronotum width; lateral margin of hemelytra almost straight, slightly rounded in posterior part; cuneal fracture weakly developed; cuneus elongated shaped; legs slender and extremely long; apical part of femur swollen; first tarsal segment longer than combination of second and third segments. Abdomen: elongate, reaching to apex of cuneus.

Genitalia. Left paramere scythe-shaped with long setae; hypophysis straight and long, its apex sharp ( Fig. 2A ); right paramere rod-shaped, hypophysis bifurcated apically ( Fig. 2B ), with three distinct spines subapically ( Fig. 2C ); endosoma membranous with two triangular medial sclerites (ms) and one broad lateral sclerite (ls) ( Fig. 2D ).

Female: Body narrowly elongated, length 8.0–8.1. Coloration. as in male. Surface and Vestiture. as in male. Structure. as in male except for proportion of antennal segment 2.0: 3.1: 6.3: 3.2, and genital segment with long ovipositor exceeding hemelytron ( Fig. 1D ). Genitalia. Sclerotized rings elongate triangular, its apex sharp ( Fig. 2E ).

Measurements (in mm). Male (n=4)/Female (n=5) Body length, clypeus-apex of membrane: 6.51–6.60/8.01–8.12; head length, excluding collar: 0.56–0.58/0.59–0.61; head width, including compound eyes: 0.95–0.97/1.02–1.05; vertex width: 0.39–0.40/0.47–0.51; 1 st antennal segment length: 2.02–2.08/2.09–2.14; 2nd antennal segment length: 3.44–3.49/ 3.19–3.30; 3rd antennal segment length: 7.27–7.32/6.29–6.44; 4th antennal segment length: 2.87–2.90/3.27–3.31; total antennal length: 15.60–15.79/14.83–15.15; 1 st labial segment length: 0.71–0.74/0.80–0.81; 2nd labial segment length: 0.73–0.76/0.86–0.88; 3rd labial segment length: 0.31–0.34/0.30–0.31; 4th labial segment length: 0.55–0.58/0.64–0.65; total labial length: 2.30–2.42/2.60–2.65; mesal pronotal length: 1.00–1.04/1.59–1.61; basal pronotal maximal width (straight): 1.05–1.07/1.19–1.22; anterior scutellum width: 0.63–0.65/0.73–0.76; mesal scutellum length: 0.53–0.54/ 0.59–0.63; commissure length: 1.73–1.75/1.93–1.97; outer embolial margin length (straight): 3.36–3.38/3.75–3.79; outer cuneal margin length (straight): 0.90–0.94/0.87–0.90; maximal width across hemelytron: 0.49–0.51/0.58–0.60; hind leg (femur: tibia: tarsus): 4.15–4.18:6.27–6.33:0.87–0.89/4.10–4.19:6.52–6.58:0.86–0.89.

Specimen examined. [ CNU] Holotype: 1♂, Cuc Phuong National Park (20°19´07˝ N 105°36´18˝E), Ninh Binh Prov., Vietnam, 10.v.2017, on Schizostachyum dullooa, J. Kim leg.; [ CNU] Paratypes: 5♂♂ 6♀♀, same data as holotype ; [ VNMN] Paratypes: 1♂ 1♀, same data as holotype .

Host: Schizostachyum dullooa (Gamble) Majumdar (Poaceae) * ( Fig. 3 ).

Biology. This species was only collected on Schizostachyum dullooa with specific host relationship. All nymphal stages (1–5 instars) and adults of this species were found on this host plant.

Etymology: Named after I. Lansbury as a recognition for his taxonomical study on the Mecistoscelini ; a noun in genitive case.

Distribution: Vietnam (Northern).

Remarks. This species is similar to its congener M. scirtetoides , but can be distinguished by larger body; right paramere with three spines; and distinct endosomal sclerites of male genitalia. In particular, the character state (three spines of right paramere) is consistent, which can be one of the important characters for this species. Lansbury (1963) also indicated the numbers of spines were one of the diagnostic characters of Mecistoscelis species in comparative notes and key.

Figures

FIGURE 1. Dorsal habitus and abdomen of male and female of Mecistoscelis lansburyi sp. nov. A: holotype, ♂; B: paratype, ♀; C: abdomen in lateral view of male; D: ditto, female. Scale bar: 1 mm.

FIGURE 2. Parameres, endosoma and bursa copulatrix of Mecistoscelis lansburyi sp. nov. A: left paramere; B: right paramere; C: three long spines at apical part of right paramere; D: endosoma; E: bursa copulatrix of female. Scale bar: 0.1mm.

FIGURE 3. Host plant, Schizostachyum dullooa.