Larval development of Austinixa bragantina (Crustacea: Brachyura: Pinnotheridae) reared in the laboratory

Abstract

The zoeal and megalopal stages of Austinixa bragantina Coelho, 2005, a small pinnotherid crab found in association with ghost shrimps Callichirus major (Say, 1818) and Lepidophthalmus siriboia Felder & Rodrigues, 1993 in the northeastern region of the state of Pará, Brazil, were reared in the laboratory from hatching to the megalopal stage. The duration of the larval period from hatching to megalopa was 28 days and the mean of duration for each larval stage was 6, 5, 5, 6, and 6 days, respectively. In the present study, the zoeal and megalopal stages are described and illustrated in detail

Morphology of the first zoeal stage of the commensal southwestern Atlantic crab Austinixa aidae (Righi 1967) (Brachyura: Pinnotheridae), hatched in the laboratory

“…Where deviations from this pattern were reported (such as 2, 3, 1, 2 and 1, 1, 1, respectively, for A. bragantina; Lima 2009), these findings require confirmation. The same applies to another observation by Lima (2009), the absence of lateral spines on the telson of the zoea I in A. bragantina. Therefore, differences between the zoea I of Austinixa larvae are probably only evident in the cephalothorax and the pleon armature.…”

“…Regarding the pleon differences, we found that A. aidae can be separated from A. bragantina and A. cristata by the presence of lateral spines on the telson. However, in A. bragantina, these spines have been reported for the zoea II and subsequent stages (Lima 2009) and thus might have been overlooked in the zoea I. We also found that A. cristata has the longest furcal arms (from the telson base) compared with A. aidae and A. bragantina.…”

Description of the first zoea of Domecia glabra Alcock, 1899 (Crustacea: Brachyura, Domeciidae) and implications for the systematics of the Trapezioidea

“…1a, 2). This distinctive zoeal character has previ-ously been described from pinnotheroid genera like Pinnaxodes major Ortmann, 1894, by Hong (1974); Pinnotheres pisum (Linnaeus, 1767) by Rice (1975); Disso- dactylus nitidus Smith, 1870, by Pohle (1989); Pinnixa gracilipes Coelho, 1997, by Lima et al (2006); and Austinixa bragantina Coelho, 2005, by Lima (2009.…”

“…Both character states are constant for known pinnotheroid larvae: Pinnaxodes major (see Hong 1974), Pinnotheres pisum (see Rice 1975), Dissodactylus nitidus (see Pohle 1989), Pinnixa gracilipes (see Lima et al 2006) and Austinixa bragantina (see Lima 2009). …”

“…Ng et al 2008], see Bolañ os et al 2005); a distally spinulate protopod without an exopod (e.g., Dissodactylus nitidus, see Pohle 1989) (Fig. 6a) and a distally spinulate protopod with a slender exopod (e.g., Pinnaxodes major, see Hong 1974; Pinnixa gracilipes, see Lima et al 2006; Austinixa bragantina, see Lima 2009) (Fig. 6b).…”