DINOFLAGELLATA, ALVEOLATA) Gómez, F
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CICIMAR Oceánides 27(1): 65-140 (2012) A CHECKLIST AND CLASSIFICATION OF LIVING DINOFLAGELLATES (DINOFLAGELLATA, ALVEOLATA) Gómez, F. Instituto Cavanilles de Biodiversidad y Biología Evolutiva, Universidad de Valencia, PO Box 22085, 46071 Valencia, España. email: [email protected] ABSTRACT. A checklist and classification of the extant dinoflagellates are given. Dinokaryotic dinoflagellates (including Noctilucales) comprised 2,294 species belonging to 238 genera. Dinoflagellatessensu lato (Ellobiopsea, Oxyrrhea, Syndinea and Dinokaryota) comprised 2,377 species belonging to 259 genera. The nomenclature of several taxa has been corrected according to the International Code of Botanical Nomenclature. When gene sequences were available, the species were classified following the Small and Large SubUnit rDNA (SSU and LSU rDNA) phylogenies. No taxonomical innovations are proposed herein. However, the checklist revealed that taxa distantly related to the type species of their genera would need to be placed in a new or another known genus. At present, the most extended molecular markers are unable to elucidate the interrelations between the classical orders, and the available sequences of other markers are still insufficient. The classification of the dinoflagellates remains unresolved, especially at the order level. Keywords: alveolates, biodiversity inventory, Dinophyceae, Dinophyta, parasitic phytoplankton, systematics. Inventario y classificacion de especies de dinoflagelados actuales (Dinoflagellata, Alveolata) RESUMEN. Se presentan un inventario y una clasificación de las especies de dinoflagelados actuales. Los dinoflagelados dinocariontes (incluyendo los Noctilucales) están formados por 2,294 especies pertenecientes a 238 géneros. Los dinoflagelados en un sentido amplio (Ellobiopsea, Oxyrrhea, Syndinea y Dinokaryota) comprenden un total de 2,377 especies distribuidas en 259 géneros. La nomenclatura de algunos taxones se ha corregido siguiendo las reglas del Código Internacional de Nomenclatura Botánica. Cuando hay secuencias disponibles, la clasificación de las especies propuesta ha seguido las filogenias moleculares de los marcadores de los ARNs de la subunidades pequeña y grande del ribosoma (SSU y LSU rADN, respectivamente). Aunque no se propone ninguna novedad taxonómica, se evidencia la necesidad de numerosos cambios. Numerosas especies cuyas secuencias están disponibles aparecen muy alejadas en las filogenias moleculares de la especie tipo de su género, lo que requerirá su transferencia a otro género conocido o el establecimiento de un nuevo género. Actualmente con los marcadores moleculares más extendidos no es posible aclarar las relaciones entre los órdenes de los esquemas taxonómicos clásicos y las secuencias disponibles de otros genes es aun insuficiente. La clasificación, muy especialmente a nivel de orden, está aún lejos de poder ser resuelta. Palabras clave: alveolados, inventario de biodiversidad, Dinophyceae, Dinophyta, fitoplancton parásito, sistemática. Gómez, F. 2012. A checklist and classification of living dinoflagellates (Dinoflagellata, Alveolata). CICIMAR Oceánides, 27(1): 65-140. INTRODUCTION using tabulation as the primary guide to rela- tionships. These authors also provide a sum- Dinoflagellates constitute one of the main mary of the earlier classifications. The classi- groups of marine and freshwater protists. Schil- fication of the dinoflagellates is being continu- ler (1931-1937) provided a description of all the ously subjected to changes according to new species, both marine and freshwater, known at findings, especially with the advances in molec- that time. Sournia (1986) gave descriptions and ular phylogeny. Saunders et al. (1997) reported illustrations of the marine genera, excluding in- the first major revision of the dinoflagellate mo- formation at the species level. Gómez (2005) lecular phylogeny. Most of the short-branched listed the species of marine free-living dinofla- SSU rDNA sequences were dispersed in clades gellates. Freshwater dinoflagellates have been with low bootstrap support that Saunders et al. compiled by Bourrelly (1970) and Popovský & (1997) named the Gymnodiniales-Peridiniales- Pfiester (1990). Since the monograph of Chat- Prorocentrales complex. At that time, these se- ton (1920), a few studies have revised the para- quences failed to resolve the relationships of sitic dinoflagellates (Cachon, 1964; Cachon & most of classical orders (Gymnodiniales, Peri- Cachon, 1987; Shields, 1994). At present, no diniales, Prorocentrales) to one another. Since study is able to respond to the total number of then, the number of sequences has increased, species of dinoflagellates. although biased towards photosynthetic spe- Fensome et al. (1993) proposed a unified cies, usually much easier to culture, and com- classification of living and fossil dinoflagellates, mon coastal species found near the specialized Fecha de recepción: 9 de enero de 2012 Fecha de aceptación: 28 de febrero de 2012 66 GÓMEZ laboratories. At present, sequences of many rors have been corrected. The checklist was species are lacking and the molecular phylo- completed with the freshwater species. Major genies did not resolve the relationships be- sources were Schiller (1931-1937), Bourrelly tween the higher ranks. The classical orders (1970) and Popovský & Pfiester (1991), and for (Peridiniales, Gymnodiniales, Prorocentrales) parasitic dinoflagellates: Chatton (1920), Ca- appear to be polyphyletic in the SSU and LSU chon & Cachon (1987) and Shields (1994). The rDNA phylogenies (Saldarriaga et al., 2004; checklist was completed and updated with the Moestrup & Daugbjerg, 2007), and even orders recent literature. such as Dinophysales (Gómez et al., 2012). The species names with their nomencla- The earlier molecular phylogenies revealed tural authorities and the year of the descrip- the apicomplexan parasites as the closer rela- tion were arranged alphabetically within the tives of dinoflagellates (Gajadhar et al., 1991). genus. Genera were ordered alphabetically The dinokaryon is a distinctive character of within each family. The authorities of each ge- the dinoflagellate core, while basal dinoflagel- nus and species were spelled according to the lates show intermediate morphological and International Plant Names Index. These name ultrastructural characters that make difficult to spellings were also used for the places of pub- establish a clear cut between the Dinokaryota lication of the suprageneric ranks (family, order and Apicomplexa. A recent study suggested and class). The International Code of Zoological that perkinsid parasites should be considered Nomenclature (I.C.Z.N.) and the International as an independent phylum (Zhang et al., 2011). Code of Botanical Nomenclature (I.C.B.N.) The exclusion of Perkinsozoa, restricted to 10 have been applied for basal dinoflagellates and species of 2 genera, has a little influence on Dinokaryota, respectively. This explained slight the total account of dinoflagellate species. En- differences in some species names. For exam- vironmental molecular surveys of SSU rRNA ple, the epithets dedicated to Édouard Chatton genes revealed the existence of novel alveo- were spelled ‘chattoni´ and ‘chattonii´ for basal late sequences indicating two large and diverse dinoflagellates and dinokaryotes, respectively. clades close to the Dinokaryota that were ini- It is often difficult to decide what species tially named Marine Alveolate Groups I and II should be considered valid. Gómez (2005) la- (López-García et al., 2001). Subsequently, it beled with an asterisk (*) the species of very has been shown that these groups correspond- doubtful validity that were not considered for ed to parasitic dinoflagellates previously placed species counting. These insufficiently known within the order Syndiniales based on several taxa were mainly constituted by species with morphologically characterized representatives too poor original descriptions, for example, for which SSU rDNA sequences were available some unarmoured dinoflagellates described (Skovgaard et al., 2005; Harada et al., 2007). from fixed material in the earlier literature with The phagotrophic free-living flagellate Oxyrrhis excessively simple line drawings. These ‘litera- (Saldarriaga et al., 2003) and the ellobiopsid ture ghosts’ have been considered valid despite parasites (Silberman et al., 2004; Gómez et al., they may correspond to species that were fur- 2009) constituted other morphologically char- ther described with more detailed descriptions. acterized clades of basal dinoflagellates. Several studies of freshwater species reported This study provides a checklist of all the a high number of new species (i.e., Schiller, described dinoflagellate species updated to 1955; Baumestier, 1957; Skvortzov, 1968). December 2011. When sequences are avail- These species are considered valid, although able, the species were organized in agreement they need to be re-investigated because they between the clades observed in the phyloge- may correspond to life stages of other known netical trees and classical ranks taxonomical species. Four species (Protoceratium, Oxy- schemes (genera, family, order, etc.). This is toxum breve) that were described lacking any not a simple task because the topology of the illustration have been listed, although exclud- trees varied with the type of molecular marker, ed of the species counting. Species names the taxa sampling, sequence length, or meth- cited in the literature, although never formally