Euschistus (Euschistus) heros ( Fabricius, 1798 )

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 : 451-452

Euschistus (Euschistus) heros ( Fabricius, 1798)

( Figs 56–58 )

Cimex heros Fabricius, 1798: 532 .

Euschistus apicalis Dallas, 1851: 203 .

Euschistus heros: Stål, 1868: 26 ; Rolston, 1974: 46–49; Bianchi et al. 2019.

Material studied. Cruz Alta : 2♂, 2♀, 24.V.2006, M. T. B. da Silva leg. ( UFRG) . Derrubadas : 1♀, 13.IV.1983, S. L. Bonatto leg. ( UFRG) ; 2♂, 1♀, 26–30.IX.1983, S. L. Bonatto leg. ( UFRG) . Santa Maria : 1♂, 1♀, X. 1980, D. Link leg. ( UFRG) .

Diagnostic features. Body dorsal and ventral surfaces castaneous. Mandibular plates subequal to clypeus, rounded apically ( Fig. 57 ). Internal angles of cicatrices of pronotum dark castaneous. Anterolateral margins of pronotum concave and serrate ( Fig. 57 ). Humeral angles dark, strongly developed, rounded apically and directed anterolaterally ( Fig. 57 ). Scutellum with pale spots and apex with large pale callosity ( Fig. 56 ). Connexivum dark castaneous with a pale macule, posterior angle produced. Posterior margin of abdominal sternite 7 acute. Body length: 10.00–11.00 mm.

Recorded host plants. Canola (Marsaro Jr. et al. 2017; Bianchi et al. 2019), maize ( Roza-Gomes et al. 2011) and soybean ( Link & Grazia 1987; Medeiros & Megier 2009; Chevarria et al. 2013; Scopel et al. 2016). Also reported feeding in mature seeds of red-root amaranth ( Amaranthus retroflexus ), and mature fruits of S olanum megalochiton , S. mauritianum and Vassobia breviflora ( Medeiros & Megier 2009) .

Distribution in Rio Grande do Sul. Augusto Pestana, Cruz Alta, Derrubadas, Passo Fundo, Santa Maria, Santa Rosa, and Três de Maio ( Fig. 58 ).

New records. Cruz Alta and Derrubadas.

Comments. This species is known as the brown bug or soybean bug. The damage results from the suction of sap from the branches or stems and from pods, limiting production. They also inject toxins, causing “leaf retention”.

Figures

FIGURES 56–58. Euschistus (Euschistus) heros. 56: Dorsal view, scale bar = 1.0 mm. 57: Head and pronotum, showing serrated anterolateral margin and projected humeral angles. 58: Distribution within Rio Grande do Sul.