Mystilus frederici Kim et Jung, 2020

Kim, Junggon & Jung, Sunghoon, 2020, Two new species of the genus Mystilus Distant (Hemiptera: Miridae: Mirinae) from Vietnam, with discussion on morphological variation based on molecular data, and a revised key for Mystilus species, Raffles Bulletin of Zoology 68, pp. 488-495 : 492-494

Mystilus frederici Kim et Jung , new species

( Figs. 2 , 3E–H )

Material examined. Holotype male ( CNU), VIETNAM: Cuc Phuong National Park , 20°19′07″N 105°36′18″E, Ninh Binh Prov., on Gigantochloa sp. , 10 May 2017, J. Kim . Paratypes: 2 males and 2 females ( CNU), VIETNAM: same data as for holotype .

Diagnosis. Recognised by the following combination of characters: frons bluish and dark brown medially; first antennal segment pale brown with dark lateral longitudinal stripe; second antennal segment as long as ½ third segment; margin of compound eye reaching margin of head laterally; scutellum bluish brown somewhat tumid laterally; cuneus hyaline, sometimes slightly tinged with greyish; left paramere covered with dense setae mostly, hypophysis long and sharp, upper margin of hypophysis concave; right paramere angled vertically, with serrate finger-like and thick hypophysis, sensory lobe without any process; endosomal sclerite with sparsely large tooth ( Fig. 3E–H ).

Description. Male. Body elongate, length 5.25–5.33. COLOURATION: generally bluish brown with hyaline hemelytra ( Fig. 2A–C ). Head: almost brown partly tinged with bluish brown; vertex brown; frons bluish brown; clypeus brown; antennae almost dark brown; first antennal segment generally pale brown. Thorax: pronotum almost bluish brown; sometimes collar with variable yellowish marking; posterior part of pronotum dark brown, with variable yellowish marking ( Fig. 2D–F ); scutellum distinct bluish brown; hemelytra almost hyaline, base of hemelytra dark brown; commissure and posterior margin of corium dark brown; cuneus hyaline, sometimes tinged with grayish; vein dark brown; femur almost pale brown except for dark apical part, with dark medial line and dark markings, inner part of femur entirely pale brown; tibia almost dark brown except for pale subapical part; tarsus dark brown. Abdomen: dark brown. SURFACE AND VESTITURE: not glabrous, dull; head with transverse wrinkle; pronotum deeply punctate; hemelytra glabrous and weakly punctate. STRUCTURE: Head: distinctly prognathous; vertex width wider than compound eye; antennae much longer than length of body, linear except for first segment; first antennal segment thicker than second antennal segment, apex of first antennal segment swollen; third antennal segment longest; proportion of first to fourth antennal segments 1.1: 2.9: 5.8: 2.8; labrum slightly shorter than first labial segment; labium exceeding hindcoxae. Thorax: pronotum trapezoid, longitudinal length longer than ½ basal maximal width; suture of collar obsolete; calli distinct swollen; scutellum somewhat tumid laterally, anterior width shorter than ½ basal pronotal width, longitudinal length shorter than commissure; lateral margin of hemelytra almost straight; cuneus elongate; legs extremely long and slender; femur apically swollen. Abdomen: rounded, reaching to apex of cuneus. GENITALIA: left paramere with dense setae mostly, hypophysis long and sharp, narrow in frontal view, upper margin of hypophysis concave ( Fig. 3E ); right paramere expanded and angled vertically, without setae, hypophysis serrate finger-like and thick ( Fig. 3F ); endosoma membranous with sclerites, sclerite oriented from ductus seminis, sclerite with some distinct tooth ( Fig. 3G, H ).

Female. Body elongate, length 5.79–5.92. COLOURATION: as in male. SURFACE AND VESTITURE: as in male. STRUCTURE: as in male except for possessing genital tube at last abdominal segment.

Measurements (in mm). Male (n=2)/Female (n=2). Body length, clypeus–apex of membrane: 5.25–5.33/5.79–5.92; head length, excluding collar: 0.46–0.47/0.48–0.49; head width, including compound eyes: 0.87–0.88/0.91–0.93; vertex width: 0.40–0.43/0.47–0.48; 1 st antennal segment length: 1.16–1.18/1.29–1.33; 2 nd antennal segment length: 2.92–2.98/3.14–3.32; 3 rd antennal segment length: 5.77– 5.81/5.92–6.07; 4 th antennal segment length: 2.81–2.86/3.22– 3.35; total antennal length: 12.66–12.83/13.57–14.07; labial length: 2.83–2.89/2.95–2.98; anterior pronotal maximal width (straight): 0.60–0.62/0.64–0.65; mesal pronotal length: 0.94–0.96/0.98–0.99; posterior pronotal maximal width (straight): 1.08–1.11/1.25–1.30; anterior scutellar width: 0.54–0.56/0.59–0.60; mesal scutellar length: 0.58– 0.59/0.60–0.61; commissure length: 0.90–0.97/1.06–1.11; outer embolial margin length (straight): 2.32–2.45/2.65–2.72; outer cuneal margin length (straight): 0.49–0.51/0.51–0.53; maximal width across hemelytron: 0.56–0.58/0.64–0.65.

Etymology. Named after Frédéric Chérot, who studied Mecistoscelini including this genus; a noun in genitive case.

Host. Gigantochloa sp. ( Poaceae : Bambusoideae ) ( Fig. 4 ).

Distribution. Vietnam (Northern).

Remarks. This new species is similar in general appearance to the species M. antrami and M. manipurensis , but it can be easily distinguished by the right paramere angled vertically and the length of second antennal segment as long as ½ length of third antennal segment. The yellowish colouration of anterior and posterior parts of pronotum is variable.

Figures

Fig. 2. Dorsal and lateral habitus with variation of Mystilus frederici, new species. A, holotype, male; B, paratype, female; C, lateral view of male; D–F, variation of pronotum colouration. Scale bar = 1 mm.

Fig. 3. Parameres and endosome of Mystilus spp. A–D, M. carvalhoi, new species; E–H, M. frederici, new species. A, E, left paramere; B, F, right paramere; C, D, G, H, endosoma; sc, sclerite; sg, secondary gonopore. Scale bar = 0.1 mm.

Fig. 4. Host plant, Gigantochloa sp.