Two records of anurophagy in Leptodactylus macrosternum from Cerrado, Brazil, with a review list of cases for the genus Leptopdactylu s (Anura: Leptodactylidae

Anurophagy represents a small percentage of anurans’ diet, however, the observation of this behavior is frequent and well-documented. Herein we reported two events of anurophagy of Leptodactylus macrosternum preying a newly metamorphosed Physalaemus nattereri and an adult Boana punctata , both in the municipality of Dois Irmãos do Buriti, Mato Grosso do Sul state, Western Brazil. Additionally, we summarized literature records of anurophagy in Leptodactylus . We found 99 records of anurophagy in different stages of development. Physalaemus nattereri and Boana punctata have never been reported as prey for Leptodactylus and this predation might be due to a combination of abundance and the high call activity during the breeding season. Anurophagy in Leptodactylus has more records for large-sized species, even in the larvae stage. Anurophagy occurrence in leptodactylids may be related to the size of the predator, habitat, and area diversity since more complex and diverse environments tend to present more anurophagy events.

Leptodactylus macrosternum reproductive activity occurs mainly during the rainy season (Prado et al. 2000, Camurugi et al. 2017).It is a generalist species with a foraging strategy between sit-and-wait and active search; its diet includes mainly coleopterans (Schaefer et al. 2006, Camurugi et al. 2017).Although anurophagy is well known for Leptodactylus species, most of the records are solely based on anecdotal observation, with the preyed anurans identified only to the order level (i.e., Anura) (e.g., Gallardo 1964, Maneyro et al. 2004, Solé et al. 2009, Camurugi et al. 2017).
Prey identification is fundamental to understanding trophic interactions (Ceron et al. 2020a), the role of anurans as energy and protein sources to other animals (Cortés-Gomes et al. 2015), the role of predators as regulators, and the possible drivers of anurophagy (Measey et al. 2015).Given the lack of specific records, herein we report two new anurophagy events of Leptodactylus macrosternum and provide a list of anurophagy cases for the genus Leptodactylus.
versidade Federal de Mato Grosso do Sul (ZUFMS-AMP).Additionally, to recover a list of anurophagy records by Leptodactylus species as predators from literature, we used the following keywords: "Leptodactylus", "Anurophagy", "Diet", "Predation" and "Cannibalism" in "Google Scholar".As a complement, we checked specialized journals such as Herpetological Review and Herpetology Notes, in the "Natural History" section.We included studies of diet, even with unidentified prey.The size category of species follows Haddad et al. (2013), who considered species as small (< 3 cm), medium (3 -10 cm), and large (> 10 cm).We included reports of predation attempts or regurgitations and exclude those that not occurred in nature (e.g., Regnet and Loebmann 2017).When information about the locality and/or photographs allowed a more precise prey and predator identification, we included it (e.g., Faivovich et al. 2005, Heyer 2005, Frost et al. 2006, Narvaes and Rodrigues 2009, Duellman et al. 2016, Magalhães et al. 2020;Gazoni et al. 2021).Details about species names originally reported by authors are in Supplementary file 1.
We found 66 references reporting events of anurophagy for a total of 99 records (101 including both records described here) (Table 1).Large-size species represent 64.35 % of the total records, Medium-size species, represent the others 35.65 % and we were not able to find anurophagy in Smallsize leptodactylids.
The four-eyed frog, P. nattereri, has inguinal macroglands that can be used against predators during deimatic display (Lenzi-Mattos et al. 2005).This species has already been reported as prey for other species of Leptodactylus (Vaz- Silva et al. 2003, França et al. 2004), however, in two events, with L. luctator (Hudson, 1892), the toxin secreted by P. nattereri was efficient to avoid predation (Rodrigues and Filho 2004).In the present report, the preyed individual was a juvenile, newly metamorphosed, which may suggest that this is a less-effective defensive method at this life stage such as occur in Rhinella arenarum (Hensel, 1867) (Regueira et al. 2016).During the night of the second event of anurophagy reported here, many B. punctata were exhibiting calling behavior.This species selects different vegetation strata to call and exhibits territorial behavior, moving 100 cm around the calling site (Brunetti et al. 2014).The combination of the high abundance and the increase in calling activity and mobility during the breeding season of these species might result in occasional encounters and subsequent predation of L. macrosternum upon B. punctata.This is the first report of Leptodactylus preying on B. punctata Although some large frogs, such as bufonids, are negligible predators of anurans (Measey et al. 2015), in leptodactylids the majority of anurophagy events are displayed by large-size frogs (Table 1).In medium size species, L. macrosternum represents half of the anurophagy records and it is the largest species of its category (Maximum SVL=9.89cm).Trophic ecology studies are paramount to follow temporal variations and the diversity of interactions (Ceron et al. 2020a(Ceron et al. , 2020b)).For that purpose, we need proper identification of both, predator, and prey species.Our literature review on anurophagy by Leptodactylus leaps further in the anuran trophic ecology, which includes new records.