Adelosgryllus rubricephalus: a new genus and species of cricket (Orthoptera: Phalangopsidae)

Abstract

RESUMO -Um novo gênero e espécie de grilo falangopsídeo Adelosgryllus rubricephalus é descrito. Ilustrações de espécimes macho e fêmea e a descrição dos escleritos fálicos, assim como os cromossomos e a distribuição geográfica conhecida são relatados. Uma discussão sobre a posição taxonômica desse grilo dentro da família Phalangopsidae é incluída.PALAVRAS-CHAVE: Grylloidea, morfologia, esclerito fálico, cromossomo ABSTRACT -Adelosgryllus rubricephalus, a new genus and species of phalangopsid cricket are described. Illustrations of male and female specimens as well as descriptions of phallic sclerites, chromosomes and geographical known distribution are furnished. A discussion on the species taxonomic status of this cricket within the family is also included.KEY WORDS: Grylloidea, morphology, phallic sclerite, chromosome During the last twenty years few more than twenty specimens of this elusive species were obtained. Some of them were collected as nymphs and completed their development in the laboratory, though some of them died before reaching the adult stage. The species was found throughout a wide brazilian territory, including the states of São Paulo, Paraná and Goiás. A single nymph specimen was observed, but not collected, far north in the Federal University, Campus in Recife, Pernambuco State. They occur in diverse habitats from "cerrado" to forest vegetation and also in urban areas, always close to the ground among leaf litter, sometimes hiding within on under rotten wood or walking in the foliage during day time. With its black body, red head, the first milimeters of the antenna flagellum black, followed by a white segment and finishing dark again, it seems to be mimicring an ant or a wasp. Material and MethodsMeiotic stages were studied in male testes fixed in Carnoy I followed by acetic aqueous solution 40% treatment during few minutes to separate the cells. Suspension was then centrifugated to aprox. 1200 r/m and the supernatant medium discarded for post fixing of the residues in Carnoy I. The centrifugation and change of fixative was repeated three times and finally the suspended cells were dropped in a hot slide until drying. The staining was done with 1% lactoacetic orcein. ResultsGeneric Characters. Ocelli absent. Males with tegmen covering approximately half the abdomen (Fig. 1) with Cu 2 vein provided with pars stridens (Fig. 2b). Lateral field of the tegmen with three branching veins (Fig 2b). Mirror divided by two veins. Female tegmina (Fig. 3) in the the majority of specimens as short triangular pads, not touching in the middle line. In some specimens the tegmina are well developed, covering most of the abdomen. In both sexes, wing in general absent, but in some specimens they are fully developed. Legs moderately short. Cephalic tibiae with an oval auditory foramina on the internal face only. Dorsal edge of the hind tibiae armed with four internal and three external movable spines, and without denticles along its whole length. The apical three external spine (Fig. 2c) are smaller than the th...

Complex mating behavior in Adelosgryllus rubricephalus (Orthoptera, Phalangopsidae, Grylloidea)

“…1-6. Mating behavior of Adelosgryllus rubricephalus Mesa & Zefa, 2004. 1, courtship position; male stridulating with raised tegmens (arrow); female behind male, arrow=palpi; 2, courtship position, arrow=spermatophore; 3, male walking back underneath the female; 4, female above position, arrow=male´s tegmens inclined forward from vertical; 5, end-to-end position; 6, male eating the spermatophore (arrow).…”

“…We describe the mating behavior of Adelosgryllus rubricephalus Mesa & Zefa, 2004. In trials carried out in laboratory we verified the following mating sequence: (1) sexual recognition by antennation; (2) courtship with male turning his abdomen towards the female, performing mediolateral antennae vibration, jerking its body antero-posteriorly and stridulating intermittently, while receptive female drums on the male's abdomen tip, cerci and hind-tibia with her palpi or foretarsi; the male then stops and stays motionless for some seconds, extrudes the spermatophore and both restart the behavioral sequence described above; (3) copulation: male underneath female; with his tegmina inclined forward, and joins his genitalia to the female's to promote sperm transference ; the female steps off the male, occurring a brief end-to-end position; (4) postcopulation: without guarding behavior; male retains the spermatophore and eats it.…”

“…Insecta, Phalangopsidae, crickets, courtship, copulation. Mesa & Zefa, 2004. Em observações realizadas em laboratório verificamos a seguinte seqüência no comportamento de acasalamento: (1) reconhecimento sexual por antenação; (2) corte, em que o macho volta seu abdômen em direção à fêmea, vibra as antenas médio-lateralmente, treme o corpo ântero-posteriormente e estridula intermitentemente, enquanto a fêmea receptiva toca a ponta do abdômen, os cercos e os fêmures posteriores do macho, com seus palpos ou tarsos anteriores; o macho então fica imóvel por alguns segundos, expõe o espermatóforo e ambos retomam a seqüência comportamental descrita acima; (3) cópula: o macho coloca-se sob a fêmea, com suas tégminas inclinadas para frente, anexa sua genitália à dela e promove a transferência do esperma; a fêmea desce de cima do macho e ocorre brevemente a posição "end-to-end" durante a separação do casal; (4) pós-cópula: não há comportamento de guarda; o macho retém o espermatóforo e o ingere.…”

“…Adelosgryllus rubricephalus Mesa & Zefa, 2004 has a wide geographical distribution, extending from northeastern to southern Brazil. They occur in diverse habitats, from "cerradão" forest vegetation, to urban areas, always close to the ground, on leaf litter, sometimes hiding within or under rotten wood, or walking on the foliage during day time (MESA & ZEFA, 2004).…”

“…They occur in diverse habitats, from "cerradão" forest vegetation, to urban areas, always close to the ground, on leaf litter, sometimes hiding within or under rotten wood, or walking on the foliage during day time (MESA & ZEFA, 2004). The aim of this paper was to describe the mating behavior in A. rubricephalus.…”