Latin American Echinoderm Biodiversity and Biogeography:Patternsand Affinities

PÉREZ-RUZAFA, A.; ALVARADO, J.J.; SOLÍS-MARÍN, F.A.; HERNÁNDEZ, J.C.; MORATA, A; MARCOS, C.; ABREU-PÉREZ, M.; AGUILERA, O.; ALIÓ, J.; BACALLADO-ARÁNEGA, J.J.; BARRAZA, E.; BENAVIDES.SERRATO, M.; BENÍTEZ-VILLALOBOS, F.; BETANCOURT-FERNÁNDEZ, L.; BORGES, M.; BRANDT, M.; BROGGER, MARTIN; BORRERO-PÉREZ, G.H.; BUITRÓN-SÁNCHEZ, B.E.; CAMPOS, L.S.; CANTERA, J.R.; CLEMENTE, S.; COHEN-RENFIJO, M.; COPPARD, S.E.; COSTA-LOTUFO, L.V.; DEL VALLE-GARCÍA, R.; DÍAZ DE VIVAR, MARÍA ENRIQUETA; DÍAZ-MARTINEZ, J.P.; DÍAZ, Y.; DURÁN-GONZÁLEZ, A.; EPHERRA, LUCÍA; ESCOLAR, MARIANA; FRANCISCO, V.; FREIRE, C.A.; GARCÍA-ARRARÁS, J.E.; GIL, DAMIÁN; GUADERAS, P.; HADEL, V.F.; HEARN, A.; HERNÁNDEZ-DELGADO, E.A.; HERRERO-PÉREZRUL, M.D.; HOOKER, Y.; HONEY-ESCADÓN, M.B.I.; LODEIROS, C.; LUZURIAGA, M.; MANSO, C.L.C.; MARTÍN, A; MARTÍNEZ, M.I.; MARTÍNEZ, S.; MORO-ABAD, L.; MUSTCHE, E.; NAVARRO, J.C.; NEIRA, R.; NORIEGA, N.; PALLEIRO-NAZAR, J.S.; PÉREZ, ANALÍA; PRIETO-RÍOS, E.; REYES, J.; RODRÍGUEZ-BARRERAS, R.; RUBILAR, TAMARA; SANCHO-MEJÍAS,

Echinoderm Research and Diversty in Latin America

SPRINGER

Lugar: Berlin; Año: 2013; p. 511 - 654

The first attempt to study the diversity and biogeography of echinoderms from Latin America was done by Maluf (1988a, b). She identified 630 species of echinoderms from southern California to southern Peru (Central Eastern Pacific orCEP). Two-thirds of all CEP echinoderms occur on the continental shelf (depth? m), with a low level of endemism. She found an increase in species richness from higher to lower latitudes, with peaks of richness in the Gulf of California, Panama and the Galápagos Archipelago, places that also have a higher number of endemic species, and are also areas with more research. The Gulf of California had a greater similarity with the tropics than the Pacific side of the Baja California peninsula and southern California, while the oceanic island of Cocos was more similar to the mainland than the Galápagos and Revillagigedo archipelagos. Moreover, she indicated the presence of five faunal transition zones related to large-scale abiotic parameters. Those transition zones were: (1) the Galápagos Islands, (2) Gulf of Guayaquil, (3) Costa Rica?Panama, (4) the mouth of the Gulf of California and (5) Central Baja California outer coast. Seventy percent of all the 265 CEP shelf restricted species were endemic to the region, 12 % were of a Northeast Pacific affinity (Oregonian and Alaska provinces), 5 % had a Southeast Pacific affinity (Magellanic and Peruvian provinces), and 13 % were widespread species. Most species in this last category were transpacific more than circumtropical, and were species associated with reefs and rocky shores (Maluf 1988b). On the Atlantic side, Price et al. (1999) analyzed a database of presence/ absence of the Asteroidea compiled by Clark and Downey (1992) that was based on records collected over 150 years. They determined geographical patterns of diversity and make comparisons between coastal and deep-sea diversity for 26 regions of the Atlantic. For 349 species, they found a higher degree of endemism in coastal waters and a greater level of similarity between regions with increasing depth. However, the number of species between bathymetrical categories was similar: 199 species at depths between 0 and 200 m, 135 and 169 species between 200 and 500 m, and 198 species at depths[500 m. The greatest number of species (81 species) was in the region between Florida and the Yucatan Peninsula, followed by the Bahamas-Caribbean (77 species) and the Caribbean and Guyana basins together with the Gulf of Mexico region (66 species). This last region possessed the highest number of endemic species of all the Atlantic Asteroidea (14 species). Regions like Guyanas-Cape Frío, Cape Frío-Río de la Plata, Río de la Plata-Tierra del Fuego-Falklands islands and the Canary islands had few endemic species (richness: 48, 22, 43, 26 species respectively; endemism: 1, 1, 8, 0 species respectively). According to Price et al. (1999) the disparity in sampling efforts is an important factor which can influence interpretation of geographic patterns. Alvarado and Cortés (2004), Alvarado et al. (2008, 2010) and Alvarado (2011) studied the diversity of echinoderms in Central America, covering both Pacific and Caribbean coast. On both coasts the class Ophiuroidea was the richest with 85 species on the Pacific side and 79 on the Caribbean coast. Panama was also the richest country in the region on both coasts, with 253 species on the Pacific coast and 154 species on the Caribbean coast. Alvarado et al. (2010) and Miloslavich et al. (2010) made an extensive review of published records on echinoderms of theCaribbean and reported a total of 433 species. Ophiuroidea was the richest class with 148 species, followed by Asteroidea (116 species). Mexico and Colombia were the richest countries with 182 and 180 species, respectively. In terms of Caribbean ecoregions, the Southwestern Caribbean was richest (283 species), followed by the Western Caribbean (268 species), the Greater Antilles (248 species), the Southern Caribbean (151 species), and lastly the Eastern Caribbean (79 species). Miloslavich et al. (2011) analyzed the marine biodiversity of South America (including the Pacific coast of Costa Rica and Panama, and excluding the Caribbean coast from Colombia and Venezuela). The best known groups in the region are fish, mollusks, crustaceans, echinoderms, cnidarians, and macroalgae. They divided the region into five subregions: (1) Eastern Tropical Pacific (223 species of echinoderms, 3.3 % of the total species, 4.4 spp./100 km of the coast, 51 % spp. in OBIS?Ocean Biogeographic Information System), (2) Humbolt Current-Chile and Peru (364 species of echinoderms, 3.6 % of the total species, 5.0 spp./100 km of the coast, 38 % spp. in OBIS), (3) Patagonian shelf-Uruguay and Argentina (207 species of echinoderms, 5.5 % of the total species, 3.7 spp./100 km of the coast, 76 % spp. in OBIS), (4) North, South and East Brazilian shelves (254 species of echinoderms, 2.8 % of the total species, 3.4 spp./100 km of the coast, 60 % spp. in OBIS) and (5) tropical west Atlantic-Venezuelan Atlantic, Guyana, Suriname and French Guyana (107 species of echinoderms, 3.9 % of the total species, 5.7 spp./ 100 km of the coast, 84 % spp. in OBIS). According to their analysis with the OBIS database, echinoderms have a low level of endemism (3.6 %) and seem to have reached a relatively stable number with few new additions. This could be the result of the lack of taxonomic expertise, limited funding for research, lack of collecting effort, and limited access to sampling sites. Sthör et al. (2012) presented a global biodiversity analysis of the class Ophiuroidea, reporting 2,064 species. They divided Latin America into three regions: East Pacific (EP), South America (SA) and West Atlantic (WA). West Atlantic was the richest region with 335 species with 60.6% of them endemic to the region, followed by EP with 186 species and 62.9 % endemics, and SA with 124 species and 24.2 % endemics. Moreover, according to their depth strata, the bathyal stratum (depths between 200 and 3,500 m) was the richest in the three regions (229 species in WA, 111 species in EP and 102 species in SA), followed by the shelf stratum (depths between 0 and 200 m) (217 spp. in WA, 92 spp. in EP and 79 spp. in SA). The abyssal (depths between 3,500 and 6,000 m) (16 spp. in WA, 28 spp. in EP and 17 spp. in SA) and the hadal strata (depths[6,500 m) (0 sp. in WA, 1 sp. in EP and SA) were less rich. On this chapter we analyze the database presented in the appendix of this book. We investigate the current patterns of diversity by country and by class of echinoderms. In addition, we analyze their biogeographical, depth, and habitat or substratum affinities.