Oceans of hypotheses – comprehensive alpha-taxonomic accounts and integrative taxonomic revisions in Marine Biology Research

Taxonomy is a hypothesis-driven science. For instance, the description, synonymization, resurrection, or new records of a species are all based on the hypothesis that a distinct, valid species exists which can be clearly identified and distinguished from other similar and/or closely related species.

Hypothesis testing in taxonomy proceeds at three levels (cf. Mayr et al. 1953).

• Alpha taxonomy (‘distinction taxonomy’): description and identification of taxa using primarily comparative morphology supported by genetics (e.g. biological barcoding, cf. Schander & Willassen 2005) and distributional data.

• Beta taxonomy (‘relationship taxonomy’): studying the relationships among taxa using phylogenetic approaches based on morphology and/or genetics and/or other sources.

• Gamma taxonomy (‘ecological and evolutionary taxonomy’): revealing population structures in species, phenotypic and developmental variability, and adaptation using biology in general (including morphology, genetics, ecology, biogeography, etc.).

Alpha taxonomy forms the basis for both beta and gamma taxonomy as well as for any biological science. Alpha-taxonomic accounts should of necessity be comprehensive, using morphological, genetic (whenever available) and distributional data, but also other relevant information (e.g. behavioural, developmental, physiological, ecological, etc.) and comparative material involving scientific collections.

Beta taxonomy comes in when a group of species, mostly subsumed under a genus or higher taxon, is revised. Taxonomic revisions should be integrative, examining phylogenetic relationships based on sound alpha-taxonomic data. Hypotheses on possible relationships among phenotypically similar species of a distinct group are tested in detail. For that purpose, a considerable amount of comparative data needs to be assembled and analysed to support existing or establish new classification hypotheses.

Gamma taxonomy, while commonly replaced by more specific ecological or evolutionary terms (e.g. population, behavioural, developmental, functional, or evolutionary ecology, etc.), comes in when combined with beta taxonomy to test both phylogenetic and ecological and/or evolutionary hypotheses. Taxonomic revisions may therefore examine hypotheses at all three taxonomy levels. For instance, they may include a new species description, revise a distinct genus, and examine the function and evolution of distinct body structures among the species of this genus and in relation to other closely or more distantly related taxa.

Our oceans represent the largest habitats on earth, inhabited by a wealth of only partly explored species, challenging us with manifold taxonomic hypotheses, to be examined. Marine Biology Research (MBRJ) wants to face this challenge by supporting comprehensive alpha-taxonomic accounts (including taxonomic reviews for a distinct region or group of species) as well as integrative taxonomic revisions. Because the latter require particular efforts and provide a large amount of valuable information for taxonomists as well as ecologists and evolutionary scientists, MBRJ has now established the new publication category ‘Taxonomic revision’ and will remunerate papers published under this category with an allowance for excessive overall size and colour pages printed free of charge.

To facilitate the ability of interested authors to find out whether their paper would fit as a comprehensive alpha-taxonomic account (being published as ‘Original article’ or ‘Short report’), we offer two recently published style examples, one featuring descriptions of two new kinorhynch species (Neves et al. 2016; see also Figure 1) and the other featuring new records and the redescription of a goatfish species (Uiblein et al. 2016). The latter paper also links to a number of earlier comprehensive alpha-taxonomic studies published in the old style of MBRJ. It would also be advantageous to consider two former editorials, one regarding the requirements of a comparative approach in taxonomic (and ecological) studies (Uiblein 2015) and one regarding the reporting of new species records based on well-elaborated taxonomic accounts (Uiblein 2014).

Figure 1. Scanning electron micrographs of three Kinorhyncha species from shallow marine sediments in the Atlantic (A) and Pacific (B,C); (A) Echinoderes lusitanicus Neves, Sørensen & Herranz, 2016, paratype (ZMUC KIN-936), off Faro, Portugal (for further information see Neves et al. 2016); (B) Dracoderes abei Higgins & Shirayama, 1990, Gamak Bay, South Korea; (C) Echinoderes aureus Adrianov, Murakami & Shirayama, 2002, Shirahama, Japan. (Photographers: Ricardo C. Neves (A) and Martin V. Sørensen (B,C)).

One of the coming issues of MBRJ will feature a paper in the new ‘Taxonomic revision’ category (Tu et al. in press). Based on comparative morphological and molecular–phylogenetic evidence, this paper incorporates inter- and intrageneric distinctions and phylogenetic relationships of the family of deep-sea precious corals (Coralliidae). The authors use a truly integrative approach that combines alpha and beta taxonomy, including the descriptions of five new species, a synonymization and redescriptions of valuable type specimens. Like the two style-example papers for alpha-taxonomic accounts referred to above, this taxonomic revision will also be made available for download via a link from the section of the online MBRJ author instructions related to this editorial. As with ‘Review articles’, interested authors of ‘Taxonomic revisions’ are welcome to contact the journal editor before submission for more detailed advice. Our firm intention is also to have selected papers of these two categories published with free access to make them widely available.

Editorial board note

I am very happy to announce the following new subject editors who have joined MBRJ since early 2016: Daniela Basso, University of Milano-Bicocca, Italy (Calcareous Algae and Marine Bioconstruction); Rui Coelho, Portuguese Institute for the Ocean and Atmosphere, Portugal (Elasmobranch Biology); Anna Fricke, Instituto Argentino de Oceanografía, CONICET, Argentina (Macroalgae Diversity and Ecophysiology); Naoko Isomura, National Institute of Technology, Okinawa College, Japan (Coral Biology and Evolution); Francesc Maynou, Institut de Ciéncies del Mar, CSIC, Spain (Invertebrate Fisheries and Bycatch); Manuela Truebano, University of Plymouth, UK (Invertebrate Physiology); Sancia van der Meij, Oxford University Museum of Natural History, UK (Crustacean systematics); and Janet Voight, The Field Museum, Chicago, USA (Mollusc Systematics). Sincere thanks and best wishes for the future to Omar Avila-Poveda, Matz Berggren, Tom Fenchel, Keiichi Sato, Mirta Teichberg, Ole Tendal, and Eric Thompson, who have left us as MBRJ subject editors.