Acrorrhinium lancialium, Yasunaga, Tomohide, Yamada, Kazutaka & Artchawakom, Taksin, 2013

Yasunaga, Tomohide, Yamada, Kazutaka & Artchawakom, Taksin, 2013, New or little known taxa of the plant bug tribe Hallodapini (Hemiptera: Heteroptera: Miridae: Phylinae) from Thailand, with descriptions of three new species of the genus Acrorrhinium Noualhier, Zootaxa 3647 (3), pp. 429-442 : 431-433

Acrorrhinium lancialium new species

(Figs. 1C–D, 2C–F, 4–7)

Diagnosis. Recognized by the generally somber brown, elongate body, large eyes, long, blade-like mesal projection of the frons (Fig. 1D), long antennal segment I that is subequal in length to head width across the eyes, hooked apex of the phallotheca ( Fig. 4 ) and form of the endosoma ( Fig. 5–6 ). Most closely related to A. inexpectatum (Josifov) and A. hongkong Schuh , from which the present new species is easily distinguished by its smaller size, longer, sword-like mesal projection of the frons, and apically hooked phallotheca. Final instar ( Fig. 2 C–F) is recognized by the general shape similar to the adult, brown body speckled with sanguineous patterns, noticeable mesal projection of the frons, long and broad antenna, and creamy spots along margins of the abdominal terga.

Description. Male: Body somber brown, elongate; dorsal surface matte or shagreened, partly speckled with small, pale spots, with very sparsely distributed, silvery, short setae. Head with sanguineous maculae behind posterior margin of eye; mesal projection of frons long, blade-like, with reddish dorsal margin. Antenna dark brown, longer than body, broad; segment I with yellow extreme apex, subequal to head width across eyes; segment III longer than width of pronotum. Labium shiny chocolate brown, exceeding beyond apex of metacoxa, reaching abdominal sternum VII. Pronotum with a pale, narrow, mesal stripe extending to apex of scutellum; mesoscutum widely dark brown; scutellum medially swollen, with pale apex; pleura dark brown, comparatively shiny; ventral margin of ostiolar canal yellowish brown. Hemelytron with sparsely distributed, silvery, short, reclining setae; clavus with a pale spot just posterior to apex of scutellum; corium with two obliquely arranged, velvety fuscous spots at middle; cuneus widely dark brown; membrane dark smoky brown. Coxa yellowish brown, except for dark procoxa; leg long; femur dark brown; tibia reddish brown; tarsus pale brown. Abdomen shiny chocolate brown. Male genitalia ( Figs. 4–6 ): Genital segment slender, apically pointed ( Fig. 4 ). Left paramere sensory lobe with a small, pointed protuberance ( Fig. 5 ). Phallotheca J-shaped, with hooked apex ( Fig. 4 ). Endosoma long, spiral and subbasally coiled, with notched margin near secondary gonopore and a short, hook-shaped branch subapically ( Figs. 5 & 6 ). Female. Unknown.

Measurements. 3: Total body length 4.4–4.6; length from apex of clypeus to cuneal fracture 3.55–3.60; head width across eyes 0.87–0.89; vertex width 0.29–0.30; lengths of antennal segment I–IV 0.82–0.87, 1.87–1.95, 1.62–1.65, 0.93–1.05; labial length 2.25–2.37; basal pronotal width 1.12–1.17; width across hemelytron 1.41–1.44; and lengths of metafemur, tibia and tarsus 1.98–2.04, 3.39–3.48, 0.31–0.33.

Etymology. From Latin, lancialium (= lancer), referring to possession of a sharp, blade-like projection on the frons.

Biology. Almost nothing is currently known on its biology. A final instar identical to this species ( Fig. 2 , C–F) was captured by sweeping planted fern in Sarika District of Nakhon Nayok Province; however, it seems not to be the true breeding host. Collection records suggest this new species has two or more generations per year.

Holotype: 3, THAILAND: Nakhon Ratchasima Prov.: SERS, 14˚30'27”N, 101˚55'39”E, 410 m alt., light trap, 12–14 Jun 2009, T. Yasunaga & K. Yamada (AMNH_PBI 00379615) ( SUT).

Paratypes. THAILAND: Nakhon Ratchasima Prov.: 13, same data as for holotype (00379616) (TYCN); 13, same locality, light trap, 20 Aug 2008, T. Yasunaga & B Shishido (00379617) (TYCN); 13, same locality, light trap, 26 Feb 2009, T. Yasunaga (00379618) (TYCN); 13, same locality, light trap, 14 Apr 2013, A. Wolski (00379630) (Inst. of Syst. & Evol. of Anim., Polish Acad. Sci., Cracow).

Additional specimen examined. Nakhon Nayok Prov.: 1 final instar, Sarika, Ban Wang Takrai, 23 Mar 2010, T. Yasunaga (preserved in Shishido personal collection, Hyogo, Japan).

Figures

FIGURE 2. Habitat of Acrorrhinium tritonion (A) and habitus images of Acrorrhinium spp., living immature individuals (B − F). A. Hibiscus tiliaceus, confirmed breeding host of A. tritonion at Rayong coast. B. Fourth instar of A. tritonion (Rayong). C − F. Fifth instar identical to A. lancialium (Nakhon Nayok).

FIGURE 4. Male genital segment (pygophore) and phallotheca of Thai hallodapines named on the figure. Scale bars 0.2 mm.

FIGURE 5. Male genitalia (left paramere and endosoma) of Thai hallodapines named on the figure. Scale bars 0.1 mm.

FIGURE 6. Images of endosoma of Thai hallodapines named on the figure.