Naslov
Protandry in the Noah’ s Ark shell (Arca noae L.)

Autori
Kekez, Lovorka ; Peharda, Melita ; Mladineo, Ivona ; Bolotin, Jakša ; Skaramuca, Boško

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
40th European Marine Biology Symposium / Ott, Jorg ; Stachowitsch, Michael ; Napetschnig, Sonja - Beč : European Marine Biology Symposium, 2005

Skup
40th European Marine Biology Symposium

Mjesto i datum
Beč, Austrija, 21.08.2005. - 25.08.2005

Vrsta sudjelovanja
Poster

Vrsta recenzije
Nije recenziran

Ključne riječi
bivalve; reproduction; Arca noae; protandry; Adriatic

Sažetak
Study of the Noah&#8217; s Arks Arca noae (L.) reproductive biology was initiated to collect data necessary for sustainable exploitation of this species and also for assessing its aquaculture potential. A. noae samples were collected in the Mali Ston Bay, south Adriatic Sea, in a period from November 2001 to October 2002 and from January to December 2004. During first year of study ten specimens were collected each month, while in the second year of study between 30 and 45 shells were collected by SCUBA at the depths between 2 and 5 m. Shell lengths were measured to the 0.1 mm and gonad samples were taken and fixed in 10 % formaldehyde (2001/02) and Davidson solution (2004). Total of 590 gonads were analysed in the laboratory using standard histological techniques. Each section was examined using a compound microscope and sexed. Macroscopic observation of gonads has shown that male gonads are whitish, while sexually mature females have orange to red coloured gonads. Overall shell lengths of analysed individuals ranged from 9.7 to 80.8 mm (50.74&plusmn ; ; 12.89 mm). Although similar range of length values were recorded for males and females, results of nonparametric Mann-Whitney Test showed that females are significantly larger than males (p<0.001). Sex ratios change with respect to length of the animal: males dominate at lengths up to 39 mm, equal distribution of females and males was recorded at shell lengths between 40 and 49 mm, while animals larger than 50 mm were predominantly females. Males appear to be changing sex at lengths higher than 30 mm. Results of analysis indicate that sexual maturity of A. noae occurs at lengths around 12 mm. Small proportion of hermaphroditic animals was recorded (2.2 %), during colder part of the year, from October to April. Their lengths ranged from 31.3 to 67.4 mm (N=13, X=49.65&plusmn ; ; 10.47 mm). This finding, together with changes in sex ratio according to size category, indicates that A. noae is a protandric hermaphrodite.

Izvorni jezik
Engleski

Znanstvena područja
Biologija

POVEZANOST RADA