Life History & Behaviour
Development
For many decapod species, hatching occurs after several days of brooding on the abdomen of females, at the zoea stage (Poore 2007; Ruppert, Fox & Barnes 2004). The larvae spend one to several months in the planktonic form until they are ready to settle after megalopa stage (Poore 2007).
Growth
The growth occurs by shedding the exoskeleton (Poore 2007); as hermit crabs grow bigger, they have to find new shells to fit in,which can be often difficult and therefore can act as the limit factor of growth (Ismail 2010; Shih and Mok 2000, see “Sell selection” section). C. latens shows sexual dimorphism with males larger than females (Gherardi & Nardone 1997). The sex ratio is balanced in small body size range, but females excess in intermediate and males become dominant in large sizes; this trend can be attributed to the difference in the energy partition between males and females, or in the ratio in the reproductive potential gained on the course of growth (Gherardi & Nardone 1997). In addition, there are sexual differences in the trend of cheliped growth as well. Gherardi and Nardone (1997) note the trend of male left chelipeds that grow fast in length but isometric in width relative to their shield length, while that of females grow isomeric in length but negatively allometric in width.
Reproduction
The size at maturity of C. latens is variable (Reese 1968), and ovigerous and non-ovigerous females do not differ significantly in size, in contrast to Calcinus laevimanus, which showed a greater size of ovigerous females (Gherardi & Nardone 1997). The positive relationship between female body size and egg number was less significant in C. latens than C. laevimanus as well (Gherardi & Nardone 1997).
The annual breeding cycle of C.latens begins from late December and continue to September (Reese 1968). In Hawaiian Islands, the percentage of ovigerous females peaks two times a year,possibly due to the breeding activities of the sympatric C. lavimanus: The first peak is in February to March, when the active breeding of C. lavimanus is just beginning, and the second peak in August is after the breeding of C. laviemanus has started to decline(Reese 1968).
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Annualbreeding pattern of sympatric C. latensand C. laevimanus
(Graph produced based on data in Reese 1968)
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Reese considered that this breeding pattern can prevent competition of planktrophic larvae between the two species and indicates the dominance of C. lavimanuslarvae (Reese 1968). Besides, the smaller clutch size of C. latens tends may result in the lesser success of C. latens in larval settlement which eventually lead to the habitat segregation (Gherardi & Nardone 1997).
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