Description of a bilateral gynandromorph in Spodoptera frugiperda (Smith, 1797) (Lepidoptera: Noctuidae) from Brazil

C T A bilateral gynandromorph of Spodoptera frugiperda was reported for the first time from Minas Gerais State, Brazil. The specimen with this trait was found among the progeny of a laboratory rearing population and exhibited dimorphism in the antennae, wings, head, thorax, and abdomen. It had a male left side and a female right side. Both the external and internal genitalia were typically those of

with a LEICA MC170 HD camera in the Ecotoxicology and Ecophysiology Laboratory and in the Termitology Laboratory of the Federal University of Viçosa, respectively. The gynandromorph specimen was deposited in the Entomology Museum of the Federal University of Viçosa.
The moth (Fig. 1a-f) exhibited bilateral dimorphism in the antennae, wings, head, thorax, and abdomen. It had a male left side and a female right side (Fig. 1a). The genitalia were typically those of a male (Fig. 1e, 1f) and (Fig. 2a-c). The clasper was visible in the X-ray image, but it appears to be less developed than that of a normal FAW (Fig. 2a, 2c) (Quimbayo et al., 2010). Sagar et al. (2020) already reported a bilateral gynandromorph for a FAW in natural conditions, although the specimen presented asymmetrical genitalia with male structures in one half of the body and female in the other.
The forewing of the male side had a brownish to rusty brown color, with a white patch near to the apical margin and a longitudinal black line near to the basal margin (Fig. 1a). It had an oval yellowish-brown oblicular spot and a reniform spot with an outline partially black washed, with a small white v-like marking (Fig. 1a). In addition, a conspicuous transparent spot in the M3 and CuA1 veins junction was seen (Fig. 1a). The forewing of the female side had a greyish-black color (Figs. 1a,1b). Both hindwings were white, with outer, anal, and inner margins black washed, mainly on the female side (Fig. 1d). The male side abdomen had a brownish color and the female side a greyishblack color (Fig. 1d). In ventral view, each abdominal sternite had a central black marking (Fig. 1b). All these traits were similar to those of a normal FAW specimen (Brévault et al., 2018;Sharanabasappa et al., 2018;Bajracharya et al., 2019).
Gynandromorphism is produced by an unequal distribution of chromosomes, especially the sexual (Mayr et al., 1953). They normally result from either loss or addition of a sex chromosome early during development, from fertilization of a binucleated egg, or delayed syngamy (Cooper, 1959;Homsher and Yunker, 1981;Narita et al., 2010). Some of the known reasons for the gynandromorph abnormalities are extreme temperatures, ultraviolet light, viral infections, and translocations of parts of the sex chromosomes and/or autosomes (Drescher and Rothenbuhler, 1963;Nekrutenko, 1965;Blau, 1978;Riotte, 1978;Marec et al., 2001). For Lepidopteran like Bombyx mori, that have a female-heterogametic chromosomal constitution (i.e., ZZ: male; ZW: female), double fertilization of a binucleate egg (ZW) by Z sperms is thought to be the major cause of gynandromorphs generation (Goldschmidt and Katsuki, 1927). Other potential causal agents of gynandromorphism are the mutations, genetic incompatibilities, and Wolbachia infection (Pereira et al., 2003;Kageyama et al., 2012). We encourage the worldwide biological collections to document the gynandromorphic and aberrant individuals deposited, such as the frequency and morphology of their deformities, an important information with applications in pest management and biomedicine (Narita et al., 2010;Sánchez-Murillo et al., 2013;Eastwood and Wood, 2019).

Acknowledgments
This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior -Brasil (CAPES) -Finance Code 001, Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG) and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) -INCT Semioquímicos na Agricultura. The second author thanks Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) for his scholarship (process # 162813/2018-0). We thank Lírio Cosme Júnior and the Laboratório de Ecotoxicologia e Ecofisiologia for the support to use the X-Ray. We also thank Og De Souza and the Termitology Laboratory for making available the optic equipment for image taking. We thank Hernane Dias Araújo for revising the manuscript and also the two anonymous reviewers that helped to improve the final version of this scientific note.