Population Biology of Uca maracoani in a Tropical Mangrove

Distribution and sexual dimorphism of the crab Xenograpsus testudinatus from the hydrothermal vent field of Kueishan Island, northeastern Taiwan

“…by individuals of two genders in younger stages are similar, so the rate of growth shows the same trend; adult males are larger in size, which contribute to interspecies competition for food, habitat and mating expediency [41,43,46], therefore the rate of growth increases faster than in females. We found in the present study that beyond a carapace width of 2.07 cm, male individuals get grew faster than in females (Fig 8).…”

“…This study found that male X. testudinatus have larger chelipeds. This may be important for provisioning females for copulation and also cause more damage during fights against other males [43].…”

“…The variation of three morphological traits of X. testudinatus indicated that the shape difference of both genders was due to sexual dimorphism. Sexual dimorphism is commonly found in crabs [43,[50][51][52][53][54]. In brachyurans, sexual dimorphism is common for females to have larger and wider abdomina than males; because they carry and incubate embryos attached to the abdominal appendages [55].…”

“…The present study found that X. testudinatus in the hydrothermal vent area had a clear pattern of sexual dimorphism by developing larger chelipeds in males, which is similar to fiddler crabs (Uca spp.) [43,51,56], and another hydrothermal vent crab M. distinguendus [13].…”

An illustrated key to the fiddler crabs (Crustacea, Decapoda, Ocypodidae) from the Atlantic coast of Brazil

“…Biological notes. The species reproduces year-round in northern (Azevedo et al 2016), northeastern (Silva et al 2016), southeastern (Hirose and Negreiros-Fransozo 2008) and southern (Benedetto and Masunari 2009) regions, but only during the dry season in northern region (Koch et al 2005). Well-established populations are typically recorded in muddy substrates of polyhaline areas of estuaries, where no other fiddler crab species was seen sharing this space (Masunari 2006).…”