Behavioral and morphological contrasts on the reproduction of two prolonged breeders of the genus Physalaemus (Anura: Leptodactylidae)

Abstract

The reproduction is one of the main events in the life of an organism, and anurans stand out among vertebrates because of the diversity of their reproductive strategies. We studied the reproduction of two syntopic species, Physalaemus aff. albonotatus and P. santafecinus, and comparatively described their reproductive activity pattern, advertisement calls, calling sites, daily calling activity, amplexus behavior, foam nests, and microhabitats in foam nests. In regards to the reproductive activity pattern, both species were defined as prolonged breeders. However, P. santafecinus exhibited a behavior like explosive breeders: it had a faster reproductive response against rains than P. aff. albonotatus. The calling activity was restricted exclusively to night hours in P. santafecinus, whereas P. aff. albonotatus called during both night and day. The advertisement calls of both species showed a rich harmonic structure, and were characterized by a bimodal harmonic dominance. The species differed significantly in microhabitat calling sites, foam nests, and microhabitats in foam nests. Namely, P. santafecinus frequently called and constructed its nests in sites more exposed than those of P. aff. albonotatus. The general differences in reproductive behaviors observed between the species principally agree with their different reproductive activity patterns.

The Taxonomic Status of Physalaemus cuqui Lobo, 1993, with the Description of a New Species of Physalaemus (Anura: Leptodactylidae) from Argentina and Paraguay

“…The mean call duration ranges from 0.91–1.77 s. The call has harmonic structure (up to eight harmonics detected), with a fundamental frequency ranging from 517–696 Hz, starting at 519–865 Hz, ending at 484–634 Hz; dominant frequency mainly over the first (range = 519–692; n = 74 calls), fourth (range = 2071–2075; n = 6), or fifth (range = 2508–2940; n = 18) harmonics (Table 4). This call was previously described by Barrio (1965) and Duré et al (2003) as Physalaemus albonotatus , and Cajade et al (2020) as P. aff. albonotatus .…”

“…Our results highlight the usefulness of bioacoustic studies to diagnose anuran lineages with meager morphological variation, but clearly divergent on molecular grounds. In this sense, the presence/absence of pulses in the advertisement calls of P. albonotatus (Márquez et al 1995; Ferrari and Vaira 2001; Köhler et al 2017) and P. cristinae (Barrio 1965; Duré et al 2003; Cajade et al 2020) respectively, allows an accurate species assignment with no major difficulties. At this point, Köhler et al (2017) show a spectrogram of P. albonotatus and consider it as an example of parallel frequency bands without harmonics.…”

“…albonotatus : Grosso et al (2019: 2, 25, their Figs. 1–2, their Table 1); Cajade et al (2020: 1–3, 5–14, their Figs. 1–3, their Tables 1–3); Oliveira et al (2022: their Table 1).…”

“…Physalaemus cristinae is externally very similar to P. cuvieri, but lacks its reddish coloration on the inguinal region in life. Further diagnostic characters are the cricoid ring being attached to the posteromedial process of the hyoid by a cartilaginous bridge (united by ligaments in P. cuvieri, Lobo 1992a), and a longer advertisement call of 0.82-1.77 s (Dure ´et al 2003;Cajade et al 2020;this work) vs. 0.26-0.31 s (Hepp and Pombal 2020a).…”

“…2, their Table 1); Adedara et al (2020: 6); Andrade et al (2020: their Table 1); Antoniazzi et al (2020: 3013, 3015, 3017–3019, 3021–3022, their Figs. 1–4, their Tables 1–3); Bruhl € et al (2020: their Table 3); Cabral et al (2020: 1127); Cajade et al (2020: 10); Fernández et al (2020: 7); Ghirardi et al (2020: 412). [Misidentifications.]…”