Comparative morphology of Neotropical Largidae (Heteroptera), with the description of new taxa.

MELO, MARÍA CECILIA; DELLAPÉ, PABLO M.

Campus Manguinhos- Fiocruz, Rio de Janeiro, Brasil.

Workshop; IV Workshop Sul-Americano em Heteroptera; 2019

Fiocruz

The Largidae comprises medium to large sized bugs (ca. 55 mm) that frequently have bright colors and are usually found on plants or on the ground. All known species are phytophagous, since they feed on seeds and sap of several dicot families, although there are occasional reports of largids feeding on dead insects and invertebrate feces. The family includes two subfamilies: Larginae from the New World and Physopeltinae from the Old World; 23 genera are recognized, being Largus Hahn the most diverse genus in the New World. The Larginae include three tribes: Largulini, Araphini and Largini, which together include fifteen genera, some of little precise definition and whose tribal assignment varies according to different authors given the absence of diagnostic characters. In order to diagnose the genera and establish their tribal assignment, we studied the external morphology and the male genitalia of the type species of most of Larginae genera, as well as other species of uncertain generic assignment. We analyzed 30 Largidae species including representatives of the three tribes, and additional species of the subfamily Physopeltinae. Specimens studied belong to the following institutions: Museo de La Plata, Buenos Aires, Argentina; Instituto Fundación Miguel Lillo, Tucumán, Argentina; Museo Argentino de Ciencias Naturales ?Bernardino Rivadavia?, Buenos Aires, Argentina; American Museum of Natural History, USA, National Museum of Natural History, USA; and Instituto de Biología, Mexico. The genital structures were dissected under a stereomicroscope, cleared in a 10% KOH solution, washed in distilled water, and preserved in a vial with glycerin. Color images were captured using a cellphone Sony Xperia A1 Ultra attached to an Olympus stereomicroscope SZX7. Multiple focal planes were merged using HeliconFocus software. Measurements are in millimeters. The chaetotaxy of head and pronotum, and the sculpturation of the legs, together with the male genitalia, particularly the shape of the parameres and structure of the aedeagus show good characters to differentiate and group taxa. As a result of this study we describe three new genera, and new species and we establish new combinations. A preliminary cladistic analysis is also presented to establish the phylogenetic relationships between the taxa studies.