Cannibalism or intraspecific predation is considered as a usual phenomenon in many natural populations of animals (Fox, 1975). Among the arthropods, this behavioral trait has been observed in many insect orders such as Lepidoptera, Odonata, Hemiptera, Mantodea, Orthoptera, Thysanoptera, Trichoptera, Blattodea, Diptera, Neuroptera, Coleoptera, and Hymenoptera (^{Capinera, 2008}; Richardson et al., 2010). Odonata is a well-known predatory insect order, where cannibalism is frequently seen in larval stages (Ilmonen & Suhonen, 2006), but rather rarely documented in case of adults. Till date, in adult Zygoptera, cannibalism has been documented in several species: Ceriagrion melanurum Selys, C. auranticum Fraser, Coenagrion puella (L.), Ischnura elegans (Vander Linden), I. graellsii (Rambur), I. verticalis (Say), I. ramburii Selys, Enallagma civile (Hagen), Pyrrhosoma nymphula (Sulzer), Archilestes grandis (Rambur), Euphaea dispar Rambur, and Hetaerina americana (Fabricius) (^{Bick & Sulzbach, 1966}; Müller, 1972; Utzeri, 1980; Robertson, 1985; Fincke, 1987; ^{Cordero, 1992}; Rolff & Kroger, 1997; Reels, 2010). Herein, a case of cannibalism is reported for the first time in Ceriagrion coromandelianum Fabricius from India.

While snapping some insects of a village garden (21°40'19.08"N; 87°34'29.75"E, 7 m.a.s.l.), near Bara Solemanpur village, Purba Medinipur district, West Bengal, India, on January 12th, 2014, at about 12:30 hs, a female of C. coromandelianum devouring a conspecific male was observed (Fig. 1). They were perched on a Marigold tree (Tithonia sp.) at about 1.5 feet height from the ground. The distance of nearby water body was about 10 m and the place of observation was characterized by flowering plants of Marigold with grassy vegetation. Ceriagrion coromandelianum is a sexually dimorphic damselfly (usually males with citron yellow abdomen and females with olive brown abdomen) widely distributed in the Oriental region (Subramanian et al., 2018). The breeding behavior of this damselfly has also been documented from India (Thaokar et al., 2018), but cannibalism or act of intraspecific predation has never been reported in this damselfly.

According to Fox (1975), factors that trigger the cannibalism are mainly starvation, density, stress, availability of victim and victim’s behavioral pattern. In larval stages of odonates, cannibalism usually occurs due to hlgh populatlon density (Van Busklrk, 1989). In case of adults the reason ¡s stlll quite vague. Utzerl (1980) flrst revlewed the ¡nstances of cannibalism ¡n adult Zygoptera and ¡n most of the cases teñerais and youngs were ¡nvolved as prey. Accordlng to Utzerl (1980), the ¡nstances of cannibalism takes place when ¡ntraspeclflc communlcatlon has falled or when the vlctlm ¡s not recognlzed as conspeclflc. Thus, he sald cannibalism ¡n Zygoptera mlght be an aspect of ordlnary predatlon.^{Corbet (1999}) has also postulated that, ¡n case of cannibalism ¡n odonates, usually mature adults predate on the teneral males that were unable to perform threat dlsplay. Rolff & Kroger (1997) mentloned that cannibalism occurred ¡n adults mostly durlng or after the coid weather perlod. As starvation occurred due to the low foraglng actlvltles durlng colder months, that trlggers the swltch ¡n food selectlon. The present example was also observed durlng the colder month of January. But, none of the speclmens were examlned ¡n the studled area, to conflrm whether they were starved or not. So, ¡t wlll be ¡nslgnlflcant to remark the starvation as one of the reasons for cannibalism ¡n the case of the present observaron. However, the present observaron also supports the hypothesls of sexual cannibalism, whlch ¡s commonly seen ¡n many specles of splders and mantls (Elgar & Nash, 1988; Lawrence, 1992), where mature témales devour the males for the beneflt of reproductlve success. In Zygoptera, sexual cannibalism was flrst presented by^{Cordero (1992}) with examples of Ischnura damselflies. Interestingly in the case of the present observation the mature female was devouring a conspeciflc male, whose colour was olive brown similar to that of female. Also in Zygoptera, cannibalism involved a mature male predating on its mature conspeciflc female (Reels, 2010). Thus, in the case of zygopteran cannibalism, both sexes acted as predator and prey. As a consequence, it will be fair enough to explain that cannibalism in zygopterans might be an aspect of ordinary predation, as put forward by Utzeri (1980).

Fig. 1: Female Ceriagrion coromandelianum devouring a conspecific male on January 12th, 2014 (Near Bara Solemanpur Village, Purba Medinipur district, West Bengal, India)