Host specificity and microhabitat preference of symbiotic copepods (Cyclopoida: Clausiididae) associated with ghost shrimps (Decapoda: Callichiridae, Callianideidae)

Abstract

Recent studies have revealed the ubiquitous nature of symbiotic relationships. While the majority of symbiotic relationships involve associations between organisms of disparate size, usually a larger host with a smaller symbiont, the degree of host specificity found among symbionts is remarkably variable. Some symbionts display extremely high plasticity in host selection, while other symbionts show perfect fidelity to a host species (Guo, Hwang, & Fautin, 1996; Ramirez, 1970) or even show preference for specific individuals within a species (Mills & Reynolds, 2002). Habitat specificity-the selection of a particular domain on or inside the host's body-is also extremely common (Smyth & Halton, 1983). For example, monogenean gill parasites almost exclusively occur on the gills of their fish hosts and may even restrict their distributions to precise locations on those gills, including specific gill arches or a single side of the gills (Bychowsky, 1961; Rohde, 1979). While there are potentially numerous reasons for this

Population differentiation in the Persian Gulf and Gulf of Oman: insights from the ghost shrimp's associated copepods, Clausidium iranensis and Clausidium persiaensis

“…The hosts are different in burrowing patterns, grooming and nutrition behaviours (Griffis & Suchanek, 1991;Sepahvand et al, 2014) and these parameters may influence the number of copepods occupying each host and consequently the haplotype diversity. Sepahvand et al (2020), claimed that, although the number of Clausidium copepods increases with the host size, the two host species vary in the degree of symbiont invasion, with large C. typa (host for C. persiaensis) hosting ∼7 times as many symbionts as the similarly sized N. jousseaumei (host for C. iranensis). Factors such as host gender and host species also affect the density of copepods (Corsetti & Strasser, 2003).…”

“…In summary, it seems that ecological, morphological, lifehistory differences of the host and Clausidium copepods as well as abiotic (historical events, ocean current) parameters construct the population structure of the copepods. However, based on Sepahvand et al (2020), host specificity and microhabitat selection of Clausidium copepods as the most important parameters of population size may have the most effective role on haplotype diversity of this group of copepods. Future studies should focus on getting a better understanding of the genetic population structure of C. iranensis and C. persiaensis as well as connectivity among populations and detailed analysis of life cycle strategies of their hosts.…”

“…Clausidium persiaensis shows no spatial genetic differentiation, while C. iranensis , even though populations are in proximity, slight spatial genetic differentiation was observed. A plausible scenario for such a haplotype diversity of Clausidium copepods is likely to be the difference in occupancy levels observed between the two copepod species as a consequence of the behaviour or physiology of their hosts, since their attachment mechanisms are the same (Sepahvand et al ., 2020). The hosts are different in burrowing patterns, grooming and nutrition behaviours (Griffis & Suchanek, 1991; Sepahvand et al ., 2014) and these parameters may influence the number of copepods occupying each host and consequently the haplotype diversity.…”

“…Sepahvand et al . (2020), claimed that, although the number of Clausidium copepods increases with the host size, the two host species vary in the degree of symbiont invasion, with large C. typa (host for C. persiaensis ) hosting ~7 times as many symbionts as the similarly sized N. jousseaumei (host for C. iranensis ). Factors such as host gender and host species also affect the density of copepods (Corsetti & Strasser, 2003).…”