See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/265377989 Host selection, host-use pattern and competition in Dissodactylus crinitichelis and Clypeasterophilus stebbingi (Brachyura: Pinnotheridae) ARTICLE in SYMBIOSIS · AUGUST 2014 Impact Factor: 1.44 · DOI: 10.1007/s13199-014-0292-0 READS 48 3 AUTHORS, INCLUDING: José Eduardo Martinelli-Filho Federal University of Pará 8 PUBLICATIONS 28 CITATIONS SEE PROFILE All in-text references underlined in blue are linked to publications on ResearchGate, Available from: José Eduardo Martinelli-Filho letting you access and read them immediately. Retrieved on: 06 April 2016 Symbiosis DOI 10.1007/s13199-014-0292-0 Host selection, host-use pattern and competition in Dissodactylus crinitichelis and Clypeasterophilus stebbingi (Brachyura: Pinnotheridae) José Eduardo Martinelli Filho & Ronan Brito dos Santos & Caio Cesar Ribeiro Received: 28 April 2014 /Accepted: 15 August 2014 # Springer Science+Business Media Dordrecht 2014 Abstract The genera Dissodactylus and Clypeasterophilus from the echinoid to avoid competition, as observed during are commensal or parasitic crabs that live in association with the experiments. We suggest a species-specific association irregular sea urchins. Only a single pinnotherid species is between C. stebbingi and C. subdepressus,while expected to occur on a sand dollar; however, during field D. crinitichelis associated mainly with E. emarginata, but also observations, D. crinitichelis and Clypeasterophilus stebbingi with C. subdepressus. Both crabs may harm the echinoids by were found co-occurring on a single host (Clypeaster consuming their spines, but additional research is necessary to subdepressus). Laboratory experiments and in situ observa- determine whether this is a parasitic association. tions were conducted to explore mechanisms of host selection and use by C. stebbingi, as well as the possibility of compe- Keywords Symbiosis . Decapoda . Echinoidea . Sand dollar tition with D. crinitichelis. Analysis of 213 specimens of Encope emarginata and 33 C. subdepressus revealed a high frequency of infestation (90 %) by brachyurans. The number 1 Introduction of D. crinitichelis was positively correlated with the size of E. emarginata. During field observations and experiments, Echinoderms are exclusively marine invertebrates, have a D. crinitichelis was able to colonize both echinoids, while wide distribution, and are one of the most abundant and C. stebbingi was found mainly on C. subdepressus.Noexclu- ecologically important components of the benthic megafauna sion was reported between individuals of the same sex for (Fell and Pawson 1966). They may comprise more than 90 % both crab species. However, D. crinitichelis may be territorial, of the metazoan biomass in the deep sea (Carters et al. 2009), since a single male occurred when adult females were added clearly showing the great importance of these organisms in to the host. D. crinitichelis and C. stebbingi co-occurred on the deeper regions. These invertebrates have different ecological same individual of C. subdepressus on rare occasions during roles, ranging from algal grazers (most sea urchins), to deposit field observations. C. stebbingi may exclude D. crinitichelis feeders (holothurians, sand dollars), filter feeders (crinoids, ophiuroids) and high-level predators (sea stars). The class Echinoidea composed of sea urchins and the J. E. Martinelli Filho (*) “irregular” sand dollars and sea biscuits (the monophyletic Oceanography Faculty, Geosciences Institute, Federal University of Irregularia), plays an additional key ecological role: their Pará, Campus Universitário do Guamá, Belém, PA 66075-110, Brazil e-mail: [email protected] walking and burrowing activities disturb sediments and or- ganic matter on the bottom, suspending them in the water J. E. Martinelli Filho column. These nutrients become available to other species and e-mail: [email protected] enhance primary production (Loher et al. 2004). Moreover, R. B. dos Santos echinoids are commonly used in toxicity tests and as indica- Biological Sciences Faculty, Federal University of Pará, Coronel José tors of environmental quality, because of their sensitivity to Porfírio, 2515, São Sebastião, 68372-040 Altamira, PA, Brazil heavy metals and organic micropollutants (Coteur et al. 2003; Ghirardini et al. 2005). C. C. Ribeiro Marine Biology Department, Biology Institute, Fluminense Federal Due to the relatively large size of echinoderms, members of University, Campus Valonguinho, 24020-140 Niterói, RJ, Brazil all classes are hosts for many symbionts. The Apicomplexa J.E. Martinelli Filho et al. are the most common protists parasitizing echinoderms primitivus and its hosts, which was concluded to be (Jangoux 1987), while a wide variety of metazoans are para- ectoparasitism with an asymmetric exploitation of two hosts. sites or symbionts. For instance, the Myzostomida are a highly A few studies on the interaction between D. crinitichelis specialized and exclusive annelid clade of echinoderm para- and its hosts have been published (Telford 1982; Reeves and sites (Eeckhaut and Jangoux 1993). Crustaceans are another Brooks 2001), but none is related to Encope emarginata,its example of common symbionts: 13 copepod families are main host on the Brazilian coast. No information about the exclusive symbionts (Boxshall and Halsey 2004), of which interaction between Clypeasterophilus stebbingi and four are obligatory parasites on sea urchins (Boxshall and Clypeaster subdepressus was found. Often, a simple survey Ohtsuka 2001). Many other taxa may be associated, although of the occurrence and distribution of species is performed, but not exclusively, with echinoderm hosts, increasing the already includes no observations on the relationship between hosts high diversity of associated organisms. and symbionts or the host-use pattern (e.g., Martins and Many echinoids are important as hosts for a diverse and D’Incao 1996). abundant fauna of other invertebrates, mainly hydrozoans, Therefore, this study explored ecological aspects in- polychaete worms, gastropods, bivalves, bryozoans, and por- cluding the host selectivity, host-use pattern and relation- celain and pinnotherid crabs (Bell and Stancyk 1983; Baeza ship between the symbionts and their hosts. The possibil- and Thiel 2000;GeorgeandBoone2003; Campos et al. 2009; ity of competition between individuals of the two crab David et al. 2009). The associated fauna displays a wide range species co-occurring on a single host was also investigat- of ecological relationships with its hosts, from obligatory ed, and the influence of intra- and interspecific competi- parasites (Matsuda et al. 2013) to facultative commensals tion on host-selection was tested. Preliminary results on (Baeza and Thiel 2003). The frequency and abundance of the diet and behavior of D. crinitichelis and C. stebbingi such symbionts are highly variable, with occurrences from are also provided from in situ observations and laboratory less than 5 % to more than 90 %, and from a single to a few experiments. hundred specimens in a single host (e.g., Ory et al. 2013). The most common crustaceans associated with echinoids are the anomuran and brachyuran crabs, and their ecological 2Materialsandmethods associations are diverse. The brachyuran Holothuriophilus tomentosus is probably an amensalist on irregular sea urchins Aspects of the ecological relationship between the pinnotherid (Wirtz et al. 2009). Baeza and Thiel (2000)suggestedastrong crabs Dissodactylus crinitichelis and Clypeasterophilus commensalism between the porcellanid Liopetrolisthes mitra stebbingi and their respective hosts Encope emarginata and and the sea urchin Tetrapygus niger, and the pinnotherid Clypeaster subdepressus were studied at Ubatuba, a munici- Dissodactylus primitivus is a known ectoparasite hosted by pality on the southeastern coast of Brazil, during austral Meoma ventricosa and Plagiobrissus grandis (De Bruyn et al. summer (January 20 to February 1) and winter (July 17 to 2011). August 3), 2011. Two relatively unimpacted beaches, located Other associations between pinnotherid crabs from the in Flamengo Bay near the research station of the Oceano- genera Dissodactylus and Clypeasterophilus and several spe- graphic Institute of the University of São Paulo, were chosen cies of echinoids have been reported. Four species of Mellita for sampling and field observations (Fig. 1). Flamengo Beach are common hosts for D. mellitae (Telford 1982;Bell1984; is about 400 m long (23° 29′48″ S, 45° 06′36″ W) and George and Boone 2003); while species of Leodia, Mellita, Lamberto Beach is about 200 m long (23° 30′42″ S, 45° 06′ Meoma, Encope and Clypeaster are hosts for D. crinitichelis 30″ W). (Telford 1982; Werding and Sanchez 1989;Reevesand Brooks 2001; Queiroz et al. 2011). Clypeaster subdepressus 2.1 Population estimates and relationship between host size is the only known host for C. stebbingi (Werding and Sanchez and number of symbionts 1989;MartinsandD’Incao 1996), and C. europacificus and C. speciosus are hosts for Clypeasterophilus usufructus (Cam- The populations of the sand dollar Encope emarginata and pos et al. 2009). its associate D. crinitichelis were estimated at Lamberto The costs and benefits of symbiosis are not always clear, and Beach, by means of free or scuba diving. Echinoids were fluctuate along a continuum that is influenced by environmen- counted, and their width (as defined by Borzone 1992) tal and biological