Calcinus elegans

Abstract: This study examined the phenomena of individuality and behavioural syndromes in three species of hermit crabs (Calcinus laevimanus, C. elegans and C. haigae) and how they are affected by the level of predator protection afforded by a shell. To examine the role of the level of predation risk, the duration of withdrawal responses of individuals was recorded following tactile manipulation under control and alarm odour conditions. To examine how shell species occupied influenced the duration of withdrawal and behavioural syndromes, crabs were in either preferred or unpreferred species of gastropod shells in C. laevimanus and C. elegans and one of the two preferred species in C. haigae. In C. laevimanus and C. elegans, but not C. haigae, crabs showed strong individuality in their withdrawal responses to predation risk, and the withdrawal response was longer in unpreferred than in preferred shells. Shell species occupied did not significantly affect the responses to levels of predation risk. In all the three cr...

Abstract: The study was conducted to determine the genetic diversity of Calcinus elegans based on sequences of the COI mitochondrial DNA. Successfully 54 samples of Garut; 43 of Yogyakarta and 47 of Banyuwangi populations were amplified by PCR using universal primers LCO 1490 and HCO 2198 successfully amplified COI gene in 625 bp, with an overall haplotype totaled 64 at 111 polymorphic sites. All population showed high genetic diversity within population interpreted by the value of gene diversity (H): Garut is 0.9266 ± 0.0251; Yogyakarta is 0.9668 ± 0.0156 and Banyuwangi is 0.9288 ± 0.0257 and the value of nucleotide diversity (π): Garut is 0.007155 ± 0.003972; Yogyakarta is 0.007966 ± 0.004387 and Banyuwangi is 0.00723 ± 0.004021. Gene diversity and nucleotide diversity did not differ significantly between populations. While genetic diversity among populations interpreted from haplotypes similarity or shared haplotype. Number of shared haplotypes among three populations is 12 haplotypes with 90 samples included. Banyuwangi population showed smallest intensity interaction with other populations indicated by the smallest value of haplotypes; polymorphic sites; hetorozigosity and distribution of larvae are influenced by spatial factor. However, three populations come from one ancestors and part of a large population. Thus the current and other environmental factors in South Coast of Java Island are effected on the genetic diversity among populations of C. elegans with a correlation coefficient is r = 0.98 (genetic diversity with current) and r = >0.90 (genetic diversity with temperature, salinity, pH, depth and distance). Key words : Calcinus elegans , genetic diversity, COI, mitochondrial DNA, haplotype

Abstract: The south coast of Java Island is comprised of rocky beaches and tidal flats that are habitats for hermit crabs. One of these is Calcinus elegans, which has high economic value as an aquarium ornament, with a greater potential for Indonesian income from export trading. These organisms have an important role in their ecosystem as detritus and scavengers. This study was conducted to determine the genetic population of C. elegans based on sequences of COI mitochondrial DNA. Fifty-four samples of Garut, 43 of Yogyakarta and 47 of Banyuwangi populations were successfully amplified using universal primers LCO 1490 and HCO 2198. Gene diversity and nucleotides are not significant among populations, while genetic diversity among populations was interpreted by shared haplotype. The number of shared haplotypes among the three populations is 12 haplotypes with 90 samples included with a proportion 62.5% from all samples. This shows that there are large interactions among populations. This interaction is indicated by ...