Sound production inCalliptamus barbarusCosta 1836 (Orthoptera: Acrididae: Catantopinae)

Abstract

Abstract. Calliptamus barbarus Costa 1836 is an acridid species whose hind femora display chromatic polymorphism that may be of ruby colour with three bold and separate femoral spots, or pale orange, with only one large femoral spot. Since both bio forms (either with three (3S) or with one (1S) spot) appear to be segregated, and their sounds constitute an intra-specifi c recognition system during mating, the sounds emitted by both groups were studied in order to identify any differences between them. It was observed that the sound is produced by mandible friction in both males and females. The temporal characteristics of the acoustic emissions of the males of both bio forms showed signifi cant differences under all conditions. In females, some differences in frequency and in temporal characteristics were also detected. Likewise males, the syllable length and the number of emitted pulses are greater in the 1S than in the 3S form. Together with other differences, these observations suggest a true separation between these bio forms, with a reproductive isolation that will probably lead to a speciation process. Résumé. Production de son chezCalliptamus barbarus Costa 1836 (Orthoptera : Acrididae : Catantopinae). Calliptamus barbarus Costa 1836 est un acridien qui présente un polymorphisme chromatique au niveau des fémurs postérieurs. Ces derniers peuvent être d'une couleur rouge rubis, avec des taches fémorales séparées et bien marquées, ou d'une couleur orange pâle, avec une seule et grande tache fémorale. Les deux formes peuvent être facilement séparées. Les sons constituant un système de reconnaissance intraspécifi que durant l'accouplement, nous avons étudié les sons produits par les deux formes pour y détecter d'éventuelles différences. Le système de production du son par friction mandibulaire, chez les mâles comme chez les femelles, a été établi. Les caractéristiques temporelles des émissions acoustiques des mâles des deux formes présentent des différences signifi catives dans toutes les situations étudiées. Certaines différences ont également été détectées chez les femelles. Pour les mâles, la durée des syllabes ainsi que le nombre des impulsions émises sont plus grands dans la forme à une tache fémorale (1S) que dans la forme à trois taches (3S). Ces faits, ajoutés à d'autres différences, suggèrent une réelle séparation, avec un isolement reproductif entre les deux formes qui pourrait conduire à un processus de spéciation.

A biometric Study of The Two Forms of Calliptamus barbarus (Costa, 1836) (Orthoptera: Calliptaminae) Living in Algeria and Spain

“…On the other hand, the temporal characteristics of the acoustic emission of the two forms of the male of C. barbarus (with one and three femoral spots) are significantly different. Some differences were also detected in females (Larrosa et al, 2008).…”

“…Among these two species, C. barbarus is the most important one, it was the subject of several studies related to different aspects: morphology (Chopard, 1943;Clemente et al, 1987, Rouibah et al, 2020, diet (Benzara et al, 2003;Mesli et al, 2005;Rouibah et al, 2018), dispersal ability (Louveaux, 1991;Termier, 1991), egg development (Fabry et al, 1987), population dynamics (Rouibah,1994(Rouibah, , 2018, sound production (Larrosa et al, 2008), ecology (Monrad,1986;Tekkouk, 2012) and molecular biology (Blanchet et al, 2012;Sofrane et al, 2015;Rouibah et al, 2016).…”

“…Chara (1987) noted that C. wattenwylianus has more ovarioles and eggs than C. barbarus. According to Larrosa et al (2008), the sound of this species is produced by the friction of mandibles in males as in females. It is an intraspecific recognition system during mating.…”

Comparison of Male and Female Morphometric Indices of the 3-Spot Form of Calliptamus barbarus (Costa, 1836), (Orthoptera: Acrididae: Calliptaminae) in Three Areas in The Jijel Region (Northeast Algeria)

“…In C. barbarus, it is performed by mandibular friction (Larrosa et al 2004), where it has been used as a means to differentiate the two bioforms of this species. Indeed, according to Larrosa et al (2008), the temporal characteristics of the acoustic emissions of males, and to a lesser degree for females, in the two bioforms showed significant differences. The length of the syllable and the number of pulses emitted are in the first bioform greater than in the second.…”

“…C. barbarus, is a species with a strong chromatic polymorphism in its posterior femurs. The color of the latter is qualified by Chopard (1943), Jago (1963), and Larrosa et al (2008) ruby red, with distinct and well-marked femoral spots, or pale yellow or orange, with a single large spot. In addition, the tibiae of this locust are reddish or orange on the inner side, yellowish and pale to the external face (Jago, 1963).…”