LYSAPSUS LIMELLUS (NCN). REPRODUCTIVE TRAITS.
MARANGONI, FEDERICO; KEHR, ARTURO I.
Society for the Study of Amphibian and Reptiles , Peabody Museum of Natural History, Yale University
Lugar: New Haven, Conecticut, USA; Año: 2000 vol. 31 p. 234 - 235
Lysapsus limellus is restricted to areas along the Paraguay and Paraná Rivers, from Rondonia and Matto Grosso (Brazil) to central Argentina. Within Argentina, L. limellus occurrs in the provinces of Chaco, Formosa, Corrientes, and Santa Fé, and north of Buenos Aires (Cei 1980. Amphibians of Argentina. Monit. Zool. Ital. (NS) Monog. 2: 609 pp.). Lysapsus limellus is very aquatic, occurring in semi-permanent and permanent ponds (Hamann and Kehr 1997. Herpetol. Rev. 28:85; Kehr and Basso 1990. Copeia 1990:573-575.). Herein we report the first reproductive traits of the species. Between February 1995 and November 1997, in seven samples, we colIected 91 specimens (43 males and 48 females). Fifteen gravid females were collected on the following dates: 17 Feb 95 (N = 5), 28 Nov 95 (N = 3),24 Feb 97 (N = 2), 10 Mar 97 (N = 1), 9 Apr 97 (N = l),A Nov 97 (N = 2), and 13 Nov 97 (N = 1). The samples were taken in four permanent and one semipermanent ponds located ea. 15 km from Corrientes city (27°30´S, 58°45´W), provine e of Corrientes, Argentina. Frogs were captured by hand between 2000 and 2200 h, preserved in 10% formalin, and deposited in the CECOAL (Centro de Ecología Aplicada del Litoral) collection (frogs captured 1995 in lot #026; 1997 in lot #544). Gravid females were 17.8-29.2 mm SVL (mean 20.2 mm; SD 2.7 mm), body mass was 0.34-1.67 g (mean 1.09 g; SD 0.37 g), mature ova count range was 35-131 (mean 76.3; SD 28.6), and mature ovum diameter range was 0.52-0.73 mm (mean 0.6 mm; SD 0.06 mm). Male SVL (N == 43) range was 13.8-19.5 mm (mean 16.99 mm; SD 1.44 mm) and body mass range was 0.43-1.5 g (mean 1.07 g; SD 0.35 g). There was significant difference in SVL between gravid andnon-gravidfemales (t-test 5.3, df 46,p <0.001), but no significant difference between body mass (t-test 0.88; df 46, p > 0.05). The difference in SVL between males and gravid females was significant, with females larger (t-test -5.84; df 56, p < 0.01), while the difference between these groups in body mass was not significant (t-test -0.25; df 56, p > 0.79). Furthermore, no significant difference was observed in SVL or body mas s between males and non-gravid females (SVL [t-test 1.65; df74, p > 0.05]; body weight [t-test 0.93; df 74, p > 0.05]). Finally, L. limellus has a reproductive mode that is characterized by eggs deposited freely in lentic water (Duellman and Trueb 1986. Biology of the Amphibians. McGraw Hill Book Co., 670 pp.). Table 1 summarizes the number and morphometric features of gravid females and males captured by each sampling date and pond type.