scholarly journals Description of the first juvenile stage of the fiddler crab Minuca mordax (Smith, 1870) (Crustacea, Decapoda, Ocypodidae)

2016 ◽  
Vol 56 (14) ◽  
pp. 163 ◽  
Author(s):  
Salise Brandt Martins ◽  
Murilo Zanetti Marochi ◽  
Setuko Masunari
Keyword(s):  
Ovigerous Female ◽  
Fiddler Crab ◽  
Juvenile Stage ◽  
Juvenile Instar ◽  
Crab Stage

The first stage of the fiddler crab Minuca mordax is described here. Zoea larvae obtained from four ovigerous female were reared in the laboratory until the development of the first crab stage. The development from zoea I to the first juvenile instar lasted 35 days after hatching. The first crab stage of Minuca mordax can be morphologically distinguished from those of Minuca burgersi and Leptuca cumulanta by a 2‑segmented antennule endopod (3‑segmented in M. burgersi, unsegmented in L. cumulanta), an unsegmented maxillule endopod (2‑segmented in M. burgersi and L. cumulanta), and a 4‑segmented first and second maxilliped endopod (respectively unsegmented and 5‑segmented in M. burgersi and L. cumulanta). The three species have the following characters in common: segmented peduncle of antennule 2; endopod of antennule unsegmented; presence of aesthetascs on the antennule; peduncle of antenna 3‑segmented; flagellum of antenna 6‑segmented; mandible 3‑segmented; maxilla with coxal and basal endite bilobed; first, second and third maxillae with exopod 2‑segmented and abdomen with six somites that are wider than long.

scholarly journals Influence of natural settlement cues on the metamorphosis of fiddler crab megalopae, Uca vocator (Decapoda: Ocypodidae)

2010 ◽  
Vol 82 (2) ◽  
pp. 313-321 ◽  
Author(s):  
Darlan J.B. Simith ◽  
Karen Diele ◽  
Fernando A. Abrunhosa
Keyword(s):  
Development Time ◽  
Chemical Cues ◽  
Fiddler Crab ◽  
Mangrove Ecosystem ◽  
Benthic Habitats ◽  
Settlement Cues ◽  
Conspecific Adult ◽  
Juvenile Crab ◽  
Crab Stage ◽  
Induction Of Metamorphosis

Megalopae of many decapod crab species accelerate their development time to metamorphosis (TTM) when exposed to natural physical and/or chemical cues characteristic of the parental habitat. In the present study, the influence of natural settlement cues on the moulting rates and development TTM in megalopae of the fiddler crab Uca vocator was investigated. The effects of mud from different habitats (including well-preserved and degraded-polluted mangrove habitats) and conspecific adult 'odours' (seawater conditioned with crabs) on the induction of metamorphosis were compared with filtered pure seawater (control). 95 to 100% of the megalopae successfully metamorphosed to first juvenile crab stage in all treatments, including the control. However, the development TTM differed significantly among treatments. Settlement cues significantly shortened development, while moulting was delayed in their absence. The fact that megalopae responded to metamorphosis-stimulating cues originating from both adult and non-adult benthic habitats demonstrates that settlement in this species may occur in a wider range of habitats within the mangrove ecosystem, including impacted areas.

MALE-MALE COMPETITION AND INTERSEXUAL INTERACTIONS IN UNDERGROUND MATING OF THE FIDDLER CRAB UCA PARADUSSUMIERI

Behaviour ◽  
1999 ◽  
Vol 136 (5) ◽  
pp. 651-667 ◽  
Author(s):  
Tsunenori Koga ◽  
Hoi-Sen Yong ◽  
Minoru Murai
Keyword(s):  
Mate Choice ◽  
Mating Success ◽  
Ovigerous Female ◽  
Fiddler Crab ◽  
Female Mate Choice ◽  
Male Competition ◽  
Feeding Time ◽  
Male Mating ◽  
Male Mating Success ◽  
Do So

AbstractWe investigated inter-male competition for female mates and intersexual interactions in underground mating (UM) of the fiddler crab Uca paradussumieri . Males search for and then enter the burrows of females that are ready to ovulate ('pre-ovigerous'). In order to ensure their paternity, these males guard the female until she ovulates the following day. Thereafter the male leaves. Intruding male conspecifics attempt to reach the female. Guarding males either fight with them (N = 27), or use the flat-claw defence (N = 96) in which the male stands in the burrow shaft and blocks the entrance with his enlarged claw. The flat-claw was a very successful defence tactic (93% success), even when the intruder was larger than the guarding male. Pre-ovigerous females accepted the first male to enter her burrow, suggesting that female mate choice does not occur. Though males that succeeded to enter the burrow of pre-ovigerous female were larger than males that failed to do so, males that succeeded UM were not larger than males that failed UM. Males that succeeded UM by a take-over were not larger than either the males that were defeated or the males that succeeded in UM after their first entering. Early localization of pre-ovigerous females was important in male mating success, as was a male's ability to defend the female before she ovulated. However, some females that were not pre-ovigerous were guarded forcibly for 2 days by males that had failed to pair with a pre-ovigerous female that day. Prolonged guarding was less successful for males than guarding for one day, probably because the males had to fight with more intruders. In addition, prolonged guarding may not be adaptive for females because they lose feeding time and mate with males that lack competitive abilities.

scholarly journals The role of adult fiddler crab environmental acoustic cues and chemical cues in stimulating molting of field-caught megalopae

2021 ◽  
Vol 537 ◽  
pp. 151516
Author(s):  
Emily E. Waddell ◽  
Wendy E.D. Piniak ◽  
Kathleen A. Reinsel ◽  
James M. Welch
Keyword(s):  
Chemical Cues ◽  
Fiddler Crab ◽  
Acoustic Cues

scholarly journals RNA-Seq reveals divergent gene expression between larvae with contrasting trophic modes in the poecilogonous polychaete Boccardia wellingtonensis

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Álvaro Figueroa ◽  
Antonio Brante ◽  
Leyla Cárdenas
Keyword(s):  
De Novo ◽  
Juvenile Stage ◽  
Type I ◽  
Rna Seq ◽  
Mrna Synthesis ◽  
De Novo Transcriptome ◽  
Larval Stages ◽  
Divergent Gene ◽  
Genetic Mechanisms ◽  
Planktotrophic Larvae

AbstractThe polychaete Boccardia wellingtonensis is a poecilogonous species that produces different larval types. Females may lay Type I capsules, in which only planktotrophic larvae are present, or Type III capsules that contain planktotrophic and adelphophagic larvae as well as nurse eggs. While planktotrophic larvae do not feed during encapsulation, adelphophagic larvae develop by feeding on nurse eggs and on other larvae inside the capsules and hatch at the juvenile stage. Previous works have not found differences in the morphology between the two larval types; thus, the factors explaining contrasting feeding abilities in larvae of this species are still unknown. In this paper, we use a transcriptomic approach to study the cellular and genetic mechanisms underlying the different larval trophic modes of B. wellingtonensis. By using approximately 624 million high-quality reads, we assemble the de novo transcriptome with 133,314 contigs, coding 32,390 putative proteins. We identify 5221 genes that are up-regulated in larval stages compared to their expression in adult individuals. The genetic expression profile differed between larval trophic modes, with genes involved in lipid metabolism and chaetogenesis over expressed in planktotrophic larvae. In contrast, up-regulated genes in adelphophagic larvae were associated with DNA replication and mRNA synthesis.

The rare Calappa tuerkayana Pastore, 1995 is a juvenile stage of the common Calappa granulata (Linnaeus, 1758) (Brachyura: Calappidae)

2021 ◽  
Author(s):  
Gianna Innocenti ◽  
Sara Fratini ◽  
Francesco Tiralongo ◽  
Chiara Natali ◽  
Fabio Crocetta
Keyword(s):  
Juvenile Stage ◽  
The Common
Sign in / Sign up

Export Citation Format

Share Document