Longitergus, Pham, Minhlan, Bai, Xiaoshuan, Heiss, Ernst & Cai, Wanzhi, 2013

Pham, Minhlan, Bai, Xiaoshuan, Heiss, Ernst & Cai, Wanzhi, 2013, Aradidae from Vietnam II. Longitergus, a new genus and two new species of micropterous Mezirinae (Hemiptera: Heteroptera: Aradidae), Zootaxa 3709 (6), pp. 556-564 : 557-558

Longitergus new genus

Type species: Longitergus productus n.sp.

Diagnosis: Micropterous, small-sized; body elongate oval; surface granulate and sparsely covered with stiff, erect bristles. Distinguished from other genera of similar habitus by the characters given in the key.

Description. Head. Shorter than width across eyes; clypeus short; antenniferous lobes long, diverging; antennae about 1.5x as long as width across eyes; segment I stout, II shortest tapering toward base, III cylindrical as long or slightly longer than I, IV shorter than II and fusiform; eyes protruding; postocular tubercles small, acutely pointed laterally, lateral margins constricted posteriorly, with some small tubercles; rostrum arising from a slit-like atrium, not reaching limits of rostral groove. Pronotum. More than 3x as wide as long at midline, trapezoidal; collar narrow; anterolateral angles not produced beyond collar; posterior margin convex medially. Mesonotum. Scutellum large, subtriangular, disk with longitudinally median tuberculate elevation; hemelytra reduced to small oval wing pads laterad of scutellum, lateral margins raised, beset with setigerous tubercles; posterior fusion line with metanotum bisinuate.

Metanotum. Strongly transverse and fused to mtgI, no fusion line discernible: separated from mtgII by a distinct transverse suture, disk with a median triangular, posteriorly widening elevation, depressed at middle.

Abdomen. MtgII fused to mtg III–VI forming tergal plate; mtg II medially depressed, raised laterally, median elevation reaching from mtg II–VI is highest on mtg III; lateral parts with shallow depressions; deltg I+II fused, triangular, reaching mesonotum, deltg III–VII separated by sutures, surface granulate, lateral margins beset with setigerous tubercles; pygophore subglobular, conical posteriorly, ptg VIII clavate.

Venter. Metathoracic scent gland canal obliquely elevated and bent dorsally, visible from above; mst III to VI raised, with median flat depression flanked by 2 (1+1) large shallow depressions, vltg III–VI with deep pits; spiracles II–VII ventral, VIII terminal.

Legs. Slender, without spines; trochanters distinct.

Etymology: The generic name refers to the elongate tergal plate unusually consisting of fused mtg II to VI.

Discussion: The new genus shows similarities to Hainanmezira Bai, Heiss & Cai 2011, Schuhaptera Heiss 2010, and Bengalaria Heiss 1982 in general body plan, although the protruding eyes and the scutellum with a longitudinal elevation resemble the genus Pahangiessa Heiss 199l; however, the new genus is micropterous and the pronotum is subtrapezoidal (vs. brachypterous, pronotum rectangular in Pahangiessa Heiss). Longitergus n.gen. differs from all similar Mezirinae genera from the Oriental Region by the tergal plate of mtg III–VI fused to mtg II. The five genera concerned can be distinguished by the following key.

Key to morphologically similar genera of Oriental Mezirinae

1 (4) Genae longer than antennal segment I.................................................................... 2 2 (3) Apex of genae blunt and rounded...................................................... Schuhaptera Heiss 2010 3 (2) Apex of genae acute and bifid........................................................ Pahangiessa Heiss 1993 4 (1) Genae shorter than antennal segment I..................................................................... 5 5 (6) MtgII fused to tergal plate, this consisting of mtg II–VI......................................... Longitergus n. gen. 6 (7) MtgII separated from tergal plate of mtg III–VI by a transverse suture........................................... 7 7 (8) Lateral margins of pronotum straightly converging anteriorly, anterolateral angles not developed, shorter than collar............................................................................... Hainanmezira Bai, Heiss & Cai 2011 8 (7) Lateral margins of pronotum subparallel on anterior lobe, anterolateral angle roundly developed, reaching anterior margin of

collar............................................................................. Bengalaria Heiss 1982