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Cephalopods of the World 1 1. INTRO DUC TION Patrizia Jereb, Clyde F.E. Roper and Michael Vecchione he increasing exploitation of finfish resources, and the commercial status. For example, this work should be useful Tdepletion of a number of major fish stocks that formerly for the ever-expanding search for development and supported industrial-scale fisheries, forces continued utilization of ‘natural products’, pharmaceuticals, etc. attention to the once-called ‘unconventional marine resources’, which include numerous species of cephalopods. The catalogue is based primarily on information available in Cephalopod catches have increased steadily in the last 40 published literature. However, yet-to-be-published reports years, from about 1 million metric tonnes in 1970 to more than and working documents also have been used when 4 million metric tonnes in 2007 (FAO, 2009). This increase appropriate, especially from geographical areas where a confirms a potential development of the fishery predicted by large body of published information and data are lacking. G.L. Voss in 1973, in his first general review of the world’s We are particularly grateful to colleagues worldwide who cephalopod resources prepared for FAO. The rapid have supplied us with fisheries information, as well as expansion of cephalopod fisheries in the decade or so bibliographies of local cephalopod literature. following the publication of Voss’s review, meant that a more comprehensive and updated compilation was required, The fishery data reported herein are taken from the FAO particularly for cephalopod fishery biologists, zoologists and official database, now available on the Worldwide web: students. The FAO Species Catalogue, ‘Cephalopods of the FISHSTAT Plus 2009. This information is supplemented by World’ by C.F.E. Roper, M.J. Sweeney and C.E. Nauen was field observations made by the authors in many parts of the published in 1984 to meet this need. world, both in preparation of the 1984 volume, as well as for the current edition. These field visits provided opportunities The number of cephalopod species that enter commercial to examine fresh material at landing sites, markets and fisheries has continued to grow significantly since 1984, as a laboratories, as well as to obtain first-hand information result of a still-growing market demand and the expansion of about local cephalopod fisheries from regional fisheries fisheries operations to new fishing areas and to deeper workers. Additional examinations of preserved specimens waters. It has been suggested that the cephalopod occurred in museums. ‘life-strategy’ may guarantee survival against environmentally stressful conditions, including those caused by heavy fishing. During the 20-plus years separating the two editions, the rapid However, as cephalopod fisheries experienced further development of cephalopod fisheries worldwide and the extensive development, parallel concern developed regarding simultaneous increase in the population of fisheries scientists, potential overexploitation. Thus, a broad consensus emerged their research and publications, made available an enormous among fishery biologists to apply the experience gained from amount of new data and research results. Sometimes it is errors made in finfish management to avoid possible failures difficult to evaluate the reliability of published data, especially in cephalopod exploitation. To help prevent potential failures, with regard to the identification of species in areas where the refined species identification capabilities are required, as well cephalopod fauna has not been sufficiently studied as a more detailed and accurate compilation of information on taxonomically. It is entirely understandable that field workers cephalopod species, distribution, biology, fisheries and catch isolated from good library and museum/collection facilities find statistics. Consequently, FAO recognized that a new edition of it difficult to correctly identify the species they encounter in the the ‘Cephalopods of the World’ catalogue was required. To field. Moreover, the discovery of new species, the more achieve this expanded goal, several authors with particular accurate delimitation of known species, or even the areas of specialization were assembled to enhance the introduction of nomenclatural changes, may cause confusion accuracy, coverage and utility of this revised catalogue. and lead to the use of scientific names that are incorrect by modern standards. Although great care was exercised to In our attempt to make this document as comprehensive evaluate and correct such published information used in the and as useful as possible, the taxonomic coverage of this preparation of this catalogue, some incorrect interpretations edition of the catalogue is organized into 3 levels of interest: may have occurred. Another potential limitation, in the taxonomic literature especially, is that information on the Level 1: species of cephalopods currently exploited economic importance of species is rather scarce or of a very commercially and species utilized at the subsistence and general nature. Also, important information may have been artisanal levels; overlooked if published only in local fisheries literature that is unavailable on an international scale. All of these potential Level 2: species of occasional and fortuitous interest to limitations, however, have been significantly mitigated during fisheries; this includes species considered to have a the preparation of the new edition because of the availability of potential value to fisheries, based on criteria such as on-line fisheries databases and bibliographic search edibility, presumed abundance, accessibility, marketability, capabilities. etc.; species of actual or potential interest to research museums also are considered under this level. With regard to the limitations mentioned above, we heartily request that readers who detect any errors in the information Level 3: species with no current interest to fisheries, which presented, or who have additional information and data that are listed only with the basic information available. will enhance the accuracy and utility of this book, please contact and inform one of the authors or the Species The inclusion of such a wide range of species is necessary Identification and Data Programme (SIDP) of the Marine to provide the most comprehensive inventory of species Resources Service, Fisheries Resources Division, Fisheries potentially useful to mankind, regardless of their current Department, FAO Rome. 2 FAO Species Catalogue for Fishery Purposes No. 4, Vol. 2 For further reading and information on cephalopod biology, overcome the considerable confusion caused by the use of fisheries and resources, several references and websites a single common name for many different species, or are listed at the end of references. several names for the same species. 1.1 Plan of the Cata logue (5) Diagnostic Features: Distinctive characters for the species are given as an aid for identification, accompanied This catalogue is organized by families and their by pertinent illustrations. Species identifications should be appropriate genera within major cephalopod groups. The attempted only after verification of the family through use of type genus within each family is treated first, then all the illustrated key to families. Reference to FAO Species remaining genera are listed alphabetically. The type Identification Guides is given wherever relevant. species within each genus is treated first, then all species are listed alphabetically. (6) Size: The known mantle length (or total length in some cases) of both males and females is provided where Level 1 includes the most important species for fisheries possible. Sizes or measurements might not be completely utilization, and it consists of detailed information in all 12 comparable because they were taken mostly from categories listed below. Level 2, which comprises those preserved or fixed specimens, but measurements of species of occasional or potential interest to fisheries, commercially important species often come from fresh consists of whatever information is available and material. Because of the elasticity of tentacles and arms, appropriate for the 12 categories. Level 3, those species for total length is not a very accurate measurement. Where which there is no current direct or indirect interest to both total length and mantle length are given, the respective fisheries, consists of basic information (i.e. scientific name, figures do not necessarily pertain to the same specimen but size, geographical distribution, literature). The format within may have been obtained from different sources. The the species sections includes the first two levels of available information on the size attained by some species treatment (Level 1 and Level 2) presented together. often is very meagre, so the maximum reported size cited Species included in Level 3 are presented at the end of here might be considerably smaller than the actual each family. maximum size. Maximum weight is given when available. Consequently, each major group and family is introduced (7) Geographical Distribution: The entire known with general descriptive remarks, illustrations of diagnostic geographic range of the species, including areas of features, highlights of the biology and relevance to seasonal occurrence, is given in the text and shown on a fisheries. The information that pertains to each species in map. In cases where only scattered records of occurrence Levels 1 and