Gonad structure in the river crab, Potamon fluviatile (Herbst, 1785) (Decapoda, Brachyura)

Abstract

In this study some reproductive aspects of Potamon fluviatile are described. Data were obtained by studying the gonad structure of both sexes using histological methods. The ovary consists of a pair of long, sac-like organs, with a thin ovarian wall surrounding the oocytes and eggs. The ovarian epithelium creates several oogenetic pouches containing growing oocytes and mature eggs, while oogonia are concentrated in a germarium within the ovarian lumen. Eggs are ovulated from the oogenetic pouches into the central ovarian lumen, transferred into the oviduct, and fertilized with sperm stored in the spermatheca. The male reproductive system consists of paired testes, united by a commissure, and genital ducts. Gametes leave the testicular tubules and reach the proximal region of the vas deferens, where the epithelium shows secretory activity. RIASSUNTOIn questo studio sono stati decritti alcuni aspetti della biologia riproduttiva di Potamon fluviatile, attraverso analisi prevalentemente morfologiche ed istologiche sulle gonadi di entrambi i sessi. L'ovario è costituito da una coppia di organi a forma di sacco, con un epitelio sottile che crea delle invaginazioni a forma di tasca con la funzione di accogliere sia oociti in fase di maturazione che uova mature, mentre gli oogoni sono organizzati all'interno del lume ovarico in gruppi ben definiti (germaria). Le uova, una volta rilasciate dalle tasche ovariche, passano nel lume e da qui, attraverso gli ovidutti, vengono depositate nella camera addominale e fecondate con gli spermatozoi conservati nella spermateca. Il sistema riproduttivo maschile, invece, consiste in una coppia di testicoli, uniti da un sottile tessuto connettivo, e da due dotti deferenti, la cui porzione prossimale mostra un'attività secretoria e dove i gameti, dopo aver lasciato i tubuli testicolari, vengono conservati fino alla loro emissione.

Spermatophore formation and sperm ultrastructure of Sundathelphusa philippina (Crustacea: Brachyura: Gecarcinucidae)

“…2009). Although still considered (Scalici et al. 2010), the scattered occurrence of cleistospermia among Old World freshwater crabs and the fact that the spermatophores are dissolved in the female spermathecae before fertilization (see Klaus et al.…”

Morphometric homogeneity and allometric growth of Potamon fluviatile in Italy

“…Specimens were measured by using Vernier calipers (to the nearest 0.05 mm) to record length (CL), height (CH) and width (CW) of the carapace, frontal width (FW, i.e., distance between the two exorbital teeth), length (ChL) and width (ChW) of both chelae, and abdomen width (AbW, as maximum width of the 5"" abdominal somite). Specimens with CL < 30 mm were considered as juveniles according to Scalici et al (2009). Raw data were analysed according to the protocol of Bertocchi et al (2008) (and references therein): linear measurements were converted to compositional data by dividing each variable by the sum of all variables for each specimen to compare the entire sample on a common scale, regardless of the type of datum.…”

Reproductive and developmental biology of rice field crab Esanthelphusa nani (Naiyanetr, 1984)

“…This structure also presents in P. fluviatile (Potamidae), and S. pictus (Trichodactylidae) freshwater crabs (Scalici et al, 2010;Silva et al, 2012). In this study, evidence of packing of spermatozoa in spermatophore in E. nani was not found in any portion of the vas deferens or even in the spermatheca of the female (Chapter V).…”

“…and Potamon fluviatile (Potamidae, freshwater crabs) (Garcia and Silva, 2006;Simeó et al, 2009;Scalici et al, 2010;Silva et al, 2012;Zara et al, 2012). Cyst form explained in G. cruentata (Grapsidae, mangrove crabs) presented the same stages of germ encasing of squamous cells (Garcia and Silva, 2006).…”

“…brachydactyla (Majidae, marine crabs), and C. danae (Portunidae, marine crabs) (Garcia and Silva, 2006;Simeó et al, 2009;Zara et al, 2012). In the freshwater crab P. fluviatile (Potamidae, freshwater crabs), MVD is also organized as a thin layer (Scalici et al, 2010). In contrast, the MVD epithelium of E. nani is thinner than epithelium of AVD which was classified as squamous epithelium.…”