Diceraeus melacanthus Dallas, 1851

Barros, Lurdiana D., Paim, Marcelo R., Krein, Verônica, Carabajal, Victor, Brandão, Marcela N., Bernardes, Paula De O. & Lindner, Mariana F., 2021, Illustrated guide to Pentatominae (Hemiptera: Pentatomidae) species associated with the four main grain crops in Rio Grande do Sul state, Brazil, Zootaxa 4958 (1), pp. 430-478 : 450-451

Diceraeus melacanthus Dallas, 1851

( Figs 53–55 )

Diceraeus melacanthus Dallas, 1851: 208 .

Dichelops melacanthus: Pennington, 1920: 8 .

Dichelops (Neodichelops) melacanthus: Grazia, 1978: 76 .

Dichelops (Diceraeus) melacanthus: Grazia & Schwertner, 2008: 234 ; Bianchi et al. 2019.

Diceraeus melacanthus: Barão et al. 2020: 10 (stat. rev. by Barão et al. 2020).

Material studied. Santa Maria: 3♀, XII.1981, D. Link. leg ( UFRG). São Sepé: 1♂, 2♀, 1981, Costa & Link leg. ( UFRG) .

Diagnostic features. Living specimens have the dorsal surface light castaneous to orange-castaneous ( Fig. 53 ) and ventral surface green ( Fig. 54 ). Mandibular plates longer than clypeus, acute apically ( Fig. 53 ). Internal angles and posterior margin of cicatrices of pronotum dark castaneous. Anterolateral margins of pronotum concave and serrate, with pale outline ( Fig. 53 ). Humeral angles dark, strongly developed into an elongate spine, directed laterally ( Fig. 53 ). Pale spots along lateral margins of scutellum and corium, apex of scutellum pale. Connexivum green in live specimens and straw-colored in mounted specimens, with anterior angles maculate and posterior angle produced. Posterior margin of abdominal sternite 7 strongly acute. Body length: 10.00 mm.

Recorded host plants: Barley, canola (Marsaro Jr. et al. 2017; Bianchi et al. 2019), maize ( Roza-Gomes et al. 2011; Panizzi et al. 2012), oat ( Pereira & Salvadori 2020; Panizzi et al. 2012), rye ( Pereira & Salvadori 2020), soybean ( Link & Grazia 1987; Panizzi et al. 2012) and wheat ( Panizzi et al. 2012).

Distribution in Rio Grande do Sul. Canoas, Encruzilhada do Sul, Guaíba, Imbé, Osório, Passo Fundo, Porto Alegre, Rio Pardo, Santa Maria, São Sepé and Torres ( Fig. 55 ).

Comments. This species is known as the green-bellied bug. Both adults and nymphs cause damage to the base of the plants, through the leaf sheath, reaching the inner leaves. Fifth instar nymphs are green.

Figures

FIGURES 53–55. Diceraeus melacanthus. 53: Dorsal view, scale bar = 1.0 mm. 54: Ventral view. 55: Distribution within Rio Grande do Sul.