Ethology of the cricket Endecous (Endecous) chape Souza-Dias & de Mello, 2017 (Orthoptera: Grylloidea: Phalangopsidae) I: Agonistic and reproductive behavior

Abstract

The mating behaviors of crickets, especially those related to agonistic encounters and oviposition, are poorly known. For example, only 10 of the 1005 valid species of Phalangopsidae have been studied to some extent. Here, we describe the reproductive behavior of Endecous (Endecous) chape, characterizing the actions involved in agonistic encounters, mating behaviors (female attraction, pair-formation, courtship, mating, and postcopulatory behavior), and oviposition. We recorded and timed agonistic, mating, and oviposition behaviors in staged trials. The male-male interactions of E. chape ranged in aggressiveness from low intensity (only antennal interaction) to high intensity (reciprocal fights). In the mating behavior, males courted females through antennation of the females' abdomen and cerci, followed by production of acoustic signals (with the exception of two males). Copulation occurred with females positioned above males (as is typical of Phalangopsidae), with an average elapsed time of 684.13 s, which is shorter than in other Phalangopsidae. We observed oviposition behavior only when three gravid females were placed together in an arena. Here, we contribute new knowledge of phalangopsid cricket behavior and provide useful information for understanding the evolution of reproductive behaviors. New characters described here can be used in phylogenetic analysis and for future studies about sexual selection and natural history.

Agonistic behavior of the neotropical cricket Eidmanacris meridionalis Desutter Grandcolas, 1995 (Orthoptera: Phalangopsidae)

“…The predominant communication behavior in crickets is stridulation, emitted to attract females (Mowles 2014), and to intimidate rival males (Alexander 1961;Jang 2011). This behavior is followed by antennation, which guarantees intraspeci c recognition and was observed in the agonistic encounters of phalangopsids Endecous (Endecous) chape and Melanotes ornata (Fianco et al, 2018;Lobregat et al 2019). In addition to stridulation, other strategies are employed by crickets, whether stridulating or not, and include, vibrational (Stritih-Peljhan and Virant-Doberlet 2021), olfactory (Stritih and Kosi 2017), auditory, and visual signaling (Shuvalov et al 1990).…”

“…In E. meridionalis, in addition to antennal recognition, another tactic employed by males in agonistic con icts is body lifting, a behavior also observed in the Phalangopsidae Endecous (Endecous) chape (Fianco et al 2018), and in the species Eidmanacris corumbatai (Prado 2006). While in E. (Endecous) chape the emphasis of agonistic behavior appears to be on stridulation, E. meridionalis positions itself for confrontation on the hind and mid-legs, keeping the trunk upright relative to the ground, in the same way as observed in E. corumbatai (Prado 2006).…”

“…Besides escaping, another observed act of submission in E. meridionalis was same-sex behavior, where the submissive male exposes its glands and lowers its body to the dominant male, resembling the copulation position between male and female (Macarini et al 2023). This practice, also observed in the agonistic behaviors of E. (Endecous) chape (Fianco et al 2018), can occur before or after the con ict position and is assumed to happen as an attempt to 'disarm' the submissive male, given that the gland is crucial for courtship and copulation because act as a nuptial gift. This is a form of agonistic behavior that may manifest in mating competition contexts, as the female may choose a male with a wellmaintained metanotal gland.…”