Temporal variation in population structure of the isopod Urobopyrus processae Richardson, 1904 (Isopoda: Bopyridae) infesting the branchial chamber of the night shrimp Ambidexter symmetricus Manning and Chace, 1971 (Decapoda: Processidae)

Abstract

Caridean shrimps are often infested by ectoparasites from the isopod family Bopyridae. Urobopyrus processae is a widespread species of bopyrid parasitizing the branchial (gill) chambers of members of the caridean family Processidae, including Ambidexter symmetricus. We examined hypotheses on differential infestation based on gender, castration of the host by the parasite, correlation between host and parasite size, and the fecundity of female parasites. Infestation rates varied from 1.3 to 32.1% between 2010 and 2011. Infested shrimps ranged from 1.26 mm to 6.24 mm carapace length (CL) between 2010 and 2011. Female shrimps were infested at a higher rate than males (2010 P = 0.0376; 2011 P = 0.0023). We report for the first time the differential selection between left and right branchial chambers in a caridean shrimp by a bopyrid parasite (P = 0.0209). Female parasite total length (TL) increased with host size (CL) in both years of sampling (2010 R 2 adj = 0.6863; 2011 R 2 adj = 0.8206). The size of male parasite TL was explained by both host CL (2010 R 2 adj = 0.4591; 2011 R 2 adj = 0.5490) and parasite female TL (2010 R 2 adj = 0.5606; 2011 R 2 adj = 0.6195). The number of embryos in a brood of the female parasite (85-3096) was varied positively with female TL (R 2 adj = 0.625). Our results show that the bopyrid-shrimp host relationship in processids is typical of those studied in other carideans, indicating similar selective pressures act on bopyrids infesting the branchial chambers of shrimps.

New occurrences, mean infestation intensity and prevalence of parasitic isopods (Isopoda, Cymothoida, Bopyridae) associated with Macrobrachium amazonicum (Decapoda, Palaemonidae) from the mouth of the Amazon River

“…mainly occurred in females of M. amazonicum . This is consistent with other studies conducted on carideans, in which parasite prevalence was found to be higher in females ( Chaplin-Ebanks & Curran, 2007 ; Rasch & Bauer, 2015 ; Barros et al, 2021 ) or equal for both sexes ( Marin Jarrin & Shanks, 2008 ). Although Pralon et al (2018) did not conclude that Probopyrus has sex-specific prevalence, due to the low number of parasites found in the specimens that they collected, our data suggest otherwise.…”

Infestation of two shrimp species of the genus Palaemon Fabricius, 1798 (Decapoda, Palaemonidae) by an isopod of the genus Probopyrus Giard & Bonnier, 1888 (Bopyridae) from the Brazilian southeast coast

“…In the present study, infestation by Probopyrus sp. occurred mostly in males of P. pandaliformis, differently from studies conducted on other carideans, in which parasite prevalence was either higher in female hosts (Chaplin-Ebanks and Curran, 2007;Rasch and Bauer, 2015) or equivalent for both sexes ( Jarrin and Shanks, 2008). With respect to P. northropi, it is not possible to conclude on its host sex-specific prevalence due to the low number of parasites found in the collected specimens.…”

The functional morphology and role of the thelycum in insemination, and its relation to the mating system in the seagrass shrimp Ambidexter symmetricus (Decapoda: Processidae)

“…) was also defined on a discrete subjective scale: 0=no embryos present, 1=embryos present and entirely comprised of yolk, 2=embryos present and blastodisc visible but no eyespot present, 3=embryos present with eyespots visible and cephalothorax and abdomen fused, 4=embryos present with cephalothorax and abdomen separated (Bauer , , ). Individuals with bopyrid isopod parasites ( Urobopyrus processae ), which castrate female A. symmetricus (Rasch & Bauer ), were not used in this study.…”