The aggressive call of Dendropsophus cruzi (Pombal & Bastos, 1998) (Anura; Hylidae) in Central Brazil

Abstract

Dendropsophus cruzi (Pombal Bastos, 1998) is a small hylid (male snout-to-vent length = 16.3-19.4 mm; female SVL = 21.3-25.0 mm) that is allocated in the D. microcephalus group (Faivovich et al. 2005). It is commonly found in Open and forested areas from Central Brazil to Provincia Velasco, Departamento de Santa Cruz, Bolivia (Frost 2017; Tessarolo et al. 2016). Pombal Bastos (1998) described the advertisement call of D. cruzi as a single pulsed note. Posteriorly, studies uncovered relationships between dominant frequency variation in the advertisement calls of D. cruzi and variation in the SVL and mass of males (Bastos et al. 2003), as well as the existence of a clinal geographic pattern in the variation of acoustic parameters of these calls (Tessarolo et al. 2016). However, the acoustic communication in anurans is usually mediated by more than one vocalization type (Toledo et al. 2015). Due the importance of call types in the social context of anurans (e.g., Reichert 2011; Forti et al. 2017), we expand the vocal repertoire of D. cruzi by describing its aggressive call.

Male aggressiveness in the tree frog <i>Dendropsophus branneri</i> (Anura, Hylidae): Physical combat, fighting call, and escalated behavior

“…Species of the D. microcephalus group, like in most Dendropsophus, may form dense breeding aggregates (e.g. Schwartz and Wells 1985), but physical combats were observed in only a few other species in this group such as D. cruzi (Pombal and Bastos 1998) (Andreani et al 2018) (Miranda et al 2008), albeit none with video recordings. This is the first description of a physical combat in D. branneri, together with the description of emitted calls.…”

“…In this type of aggressiveness, male-male interactions may include chasing, emission of encounter calls, escalating to the last resource, i.e., physical combat. The actual descriptions of this type of behavior are scarce for the whole genus with examples including D. cruzi (Andreani et al, 2018), D. ebraccatus (Wells and Schwartz, 1984), D. microps (Peters, 1872) (Toledo and Martins 2020), D. minutus (Peters, 1872) (Haddad 1987), D. nanus (Boulenger, 1889), D. sanborni (Schmidt, 1944 (Martins and Jim 2003), D. parviceps (Boulenger, 1882) (Amézquita and Hödl 2004) and D. werneri (Miranda et al 2008). Detailed reports of aggressive behaviors are important because they allow researchers to test hypotheses on the evolution of territoriality and aggressiveness in frogs (e.g.…”