Early development of fat snook, <i>Centropomus parallelus</i> (Poey 1860) (Teleostei, Centropomidae) from Southeastern Brazil

Abstract

Early development of fat snook, Centropomus parallelus (Poey 1860), is described based on embryos and larvae obtained from rearing experiments and from specimens caught in the field, in Cananéia, southeastern Brazil, during December 1999-January 2000. Larvae of common snook, C. undecimalis, were also collected to compare the pigmentation pattern and body shape. Eggs of C. parallelus were relatively small (0.65 to 0.70 mm in diameter), spherical, and usually with a single oil globule. Notochord length (NL) of newly hatched ranged between 1.1 mm to 1.4 mm. Notochord flexion began at 3.4 mm NL and was usually completed by 4.0 mm SL. Larval and early juvenile of both species were very similar with tenuous distinction, however, some morphological and pigmentation characters were used to distinguish their early stages. The main differences were as follow: trend of lower values of the ratio of body depth to body length (BD/BL) for C. parallelus larger than 10.0 mm SL; absence of the post-temporal spine in C. undecimalis; absence of pigmentation along the dorsal midline of C. parallelus larvae by 2.6-7.0 mm; and presence of a pair of dendritic melanophores posterior to the bases of pelvic fins in C. parallelus larger than 6.0.

Larval development of the Mexican Snook, Centropomus poeyi (Teleostei: Centropomidae)

“…Comparison to Centropomus undecimalis and C. parallelus. External development of C. poeyi is very similar to that previously described for both C. undecimalis (Potthoff, Tellock, 1993) and C. parallelus (Itagaki et al, 2013) with most developmental landmarks occurring at approximately the same size in all three species and with only a few notable differences. The pectoral fins appear to develop at a smaller body size in C. poeyi than in the other two species, with fin ray development occurring between 4.4-6.9 mm SL.…”

“…Surprisingly, however, there has been very little research focused on the early morphological development of centropomids. Currently only five studies have examined early morphological development in two species of snook, including, Centropomus undecimalis (Bloch, 1792), the common snook (Lau, Shafland, 1982;Potthoff, Tellock, 1993;Wittenrich et al, 2009;Yanes-Roca et al, 2015), and Centropomus parallelus Poey, 1860, the fat snook (Itagaki et al, 2013). Through the efforts of a fledgling captive propagation program for centropomids of the Gulf of Mexico at the Laboratorio de Acuicultura Tropical (Universidad Juárez Autónoma de Tabasco), early developmental material (larvae and juveniles) were obtained for a third species of centropomid, Centropomus poeyi Chávez, 1961, the Mexican snook.…”

“…The pectoral fins appear to develop at a smaller body size in C. poeyi than in the other two species, with fin ray development occurring between 4.4-6.9 mm SL. In C. undecimalis pectoral-fin ray development occurs at sizes approximately 2 mm larger (6.2-9.1 mm SL; Potthoff, Tellock, 1993) when compared to C. poeyi and the pectoralfin rays do not begin to appear until sizes greater than 5 mm SL in C. parallelus (Itagaki et al, 2013). Similarly, the fin rays of the pelvic fin start to appear at a smaller body size in C. poeyi (5.3 mm SL) when compared to that of C. undecimalis (6.6 mm SL) or C. parallelus (6.5 mm SL) although the full complement of pelvic-fin rays is present at approximately the same size in all three species.…”

“…Several aspects of larval pigmentation in C. poeyi differ from that of C. undecimalis or C. parallelus. According to Itagaki et al (2013), individuals between 2.6 mm NL and 7.0 mm SL of C. parallelus do not possess any pigmentation along the dorsal midline, an important character that can be used to distinguish larvae of C. parallelus from larvae of C. undecimalis, in which pigment is present along the dorsal midline at these sizes. Like C. undecimalis, C. poeyi also possesses clusters of melanophores at distinctive locations along the dorsal midline within this size range allowing it to be distinguished from C. parallelus.…”