The Tree Cricket Neoxabea brevipes Rehn, 1913 (Orthoptera: Gryllidae: Oecanthinae) from the Brazilian southern Atlantic Forest: morphology, <br />bioacoustics and cytogenetics

Abstract

In this paper we improve the morphological description of the tree cricket Neoxabea brevipes Rehn, 1913 and a new occurrence record for the species at the São Francisco de Paula National Forest Conservation Unit, State of Rio Grande do Sul, southern Brazil. Morphological characterization is provided together with illustrations emphasizing the most significant diagnostic features, such as the metanotal gland, abdominal specializations and phallic sclerites. The calling song was field recorded, comprising a continuous trill with dominant frequency of 3.6 kHz (19.7°C). The karyotype was described for the first time to Neoxabea Kirby, 1906, including diploid number of 2n=26, with two sexual chromosomes.

Study of four Neotropical species of tree crickets Oecanthus Serville, 1831 (Orthoptera, Gryllidae) using cytogenetic and molecular markers

“…Oecanthus Serville, 1831 is the largest genus, with 74 described species and a worldwide distribution ( Walker, 1962 ; Cigliano et al, 2021 ). Described karyotypes of oecanthine crickets show variations in the chromosome number, morphology, and sex-chromosome system, although the chromosome sets of only eight species have been studied so far ( Johnson, 1931 ; Makino, 1932 ; Ohmachi, 1935 ; Kitada, 1949 ; Hewitt, 1979 ; Milach et al, 2016 ; Zefa et al, 2018 ). One of these is Neoxabea brevipes Rehn, 1913, with 2n = 24 autosomes + two sex chromosomes (XY or X 1 X 2 0) ( Zefa et al , 2018 ); the other seven species belong to the genus Oecanthus ( Johnson, 1931 ; Makino, 1932 ; Ohmachi, 1935; Kitada, 1949; Hewitt, 1979 ; Milach et al , 2016 ).…”

“…Described karyotypes of oecanthine crickets show variations in the chromosome number, morphology, and sex-chromosome system, although the chromosome sets of only eight species have been studied so far ( Johnson, 1931 ; Makino, 1932 ; Ohmachi, 1935 ; Kitada, 1949 ; Hewitt, 1979 ; Milach et al, 2016 ; Zefa et al, 2018 ). One of these is Neoxabea brevipes Rehn, 1913, with 2n = 24 autosomes + two sex chromosomes (XY or X 1 X 2 0) ( Zefa et al , 2018 ); the other seven species belong to the genus Oecanthus ( Johnson, 1931 ; Makino, 1932 ; Ohmachi, 1935; Kitada, 1949; Hewitt, 1979 ; Milach et al , 2016 ). Neoxabea brevipes and O. valensis Milach and Zefa, 2016 inhabit the Neotropical bioregion; O. nigricornis Walker, 1869 and O. quadripunctatus Beutenmüller, 1894 the Nearctic; O. longicauda Matsumura, 1904 and O. pellucens (Scopoli, 1763) the Paleoarctic; and O. indicus Saussure, 1878 and Oecanthus sp.…”