Development of secondary sexual characters in the seabob shrimpXiphopenaeus kroyeri(Heller 1862) (Crustacea, Decapoda, Penaeidae): a scanning electron microscope study

Abstract

The development of secondary sexual characters, the petasma, and thelycum growth were studied in Xiphopenaeus kroyeri. In adult females, the thelycum is a single plate and its anterolateral portion is characterized by a reduced hood. The aperture resembles a transverse ridge. In immature stages, the ridge has a space between the plates, which becomes narrower as it reaches the end of development. The female gonopore is 'comma' shaped. In adult males, the endopods of the petasma are linked at the dorsomedial margin by a large quantity of cincinnuli. In juveniles, cincinnuli gradually increase in number until they join both endopods. At the end of development the petasma is T-shaped. The male gonopore is C-shaped. The relative growth of the petasma total length versus juvenile body length showed a highly positive allometry, whereas in adults the growth was isometric. For the relationship carapace length versus thelycum width, the juvenile phase of females is characterized by an isometry and the adult phase by a negative allometry.

Spermatogenesis and sperm assessment in the Black Tiger Prawn, Penaeus monodon

“…The external genitalia of P. monodon are similar to those observed in the subgenus Farfantepenaeus (Bauer, 1991). While the semi-closed petasma in the subgenera of Penaeus and Farfantepenaeus is more flexible than the semi-closed petasma in Trachypenaeus and Xiphopenaeus (Bauer, 1986;Fransozo et al, 2011), the interspace between the petasmal halves in the former semi-closed type is more compressed than that of the flexible open petasma in Litopenaeus (Bauer, 1991).…”

“…Benthesicymidae is regarded to be in a transitional state, as the species in this family possess an open petasma and a closed thelycum with a single spermatheca (Vereshchaka et al, 2017). The highest structural complexity of external genitalia in prawns is exhibited as a semi-closed petasma with terminal spouts and a closed thelycum with paired spermathecae (seminal receptacles), such as in the family Sicyoniidae and the subgenera Trachypenaeus and Xiphopenaeus of the family Penaeidae (Bauer, 1986;Fransozo et al, 2011).…”

The functional anatomy of external genitalia in the black tiger prawn (Penaeus monodon) studied by micro‐computed tomography and scanning electron microscopy

“…Benthesicymidae is regarded to be in a transitional state, as the species in this family possess an open petasma and a closed thelycum with a single spermatheca (Vereshchaka et al, ). The highest structural complexity of external genitalia in prawns is exhibited as a semi‐closed petasma with terminal spouts and a closed thelycum with paired spermathecae (seminal receptacles), such as in the family Sicyoniidae and the subgenera Trachypenaeus and Xiphopenaeus of the family Penaeidae (Bauer, ; Fransozo, Carvalho dos Santos, López‐Greco, & Júnior, ).…”

“…The external genitalia of P. monodon are similar to those observed in the subgenus Farfantepenaeus (Bauer, ). While the semi‐closed petasma in the subgenera of Penaeus and Farfantepenaeus is more flexible than the semi‐closed petasma in Trachypenaeus and Xiphopenaeus (Bauer, ; Fransozo et al, ), the interspace between the petasmal halves in the former semi‐closed type is more compressed than that of the flexible open petasma in Litopenaeus (Bauer, ).…”

Distribuição espaço-temporal das capturas do camarão sete-barbas na Armação do Itapocoroy, Penha, SC

“…Além da variação temporal, trabalhos pretéritos registraram que os organismos jovens da espécie são capturados principalmente em águas mais rasas, como praias, baías e enseadas (NAKAGAKI e NEGREIROS-FRANSOZO, 1998;BRANCO et al, 1999;CASTRO et al, 2005;COSTA et al, 2007;CASTILHO et al, 2008;FRANSOZO et al, 2011), enquanto que em profundidades ao redor dos 20 m, encontram-se os camarões com comprimento acima dos 11 cm, que efetivamente participam da reprodução (BRANCO, 2005;GRAÇA-LOPES et al, 2007).…”