Messing, Charles G.

NSU Works

Nova Southeastern UniversityNSUWorksOceanography Faculty Articles Department of Marine and Environmental Sciences7-1-1981Notes on Recent Changes in TanaidaceanTerminologyCharles G. MessingNova Southeastern University, messingc@nova.eduFind out more information about Nova Southeastern University and the Oceanographic Center.Follow this and additional works at: http://nsuworks.nova.edu/occ_facarticlesPart of the Marine Biology Commons, and the Oceanography and Atmospheric Sciences andMeteorology CommonsThis Article is brought to you for free and open access by the Department of Marine and Environmental Sciences at NSUWorks. It has been acceptedfor inclusion in Oceanography Faculty Articles by an authorized administrator of NSUWorks. For more information, please contactnsuworks@nova.edu.Recommended CitationMessing, Charles Garrett. "Notes on recent changes in tanaidacean terminology." Crustaceana (1981): 96-101.Notes on Recent Changes in Tanaidacean TerminologyAuthor(s): Charles Garrett MessingSource: Crustaceana, Vol. 41, No. 1 (Jul., 1981), pp. 96-101Published by: BRILLStable URL: http://www.jstor.org/stable/20103639 .Accessed: 12/06/2014 14:57Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at .http://www.jstor.org/page/info/about/policies/terms.jsp .JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range ofcontent in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new formsof scholarship. For more information about JSTOR, please contact support@jstor.org. .BRILL is collaborating with JSTOR to digitize, preserve and extend access to Crustaceana.http://www.jstor.org This content downloaded from 137.52.76.29 on Thu, 12 Jun 2014 14:57:22 PMAll use subject to JSTOR Terms and Conditions96 NOTES AND NEWS Fig. 1. Anthessius nortoni Illg, 1960. a, second antenna of male paratype, anterodorsal; b, second antenna of female paratype, posteroventral. Scale applies to both figures. REFERENCES Illg, P., 1960. Marine copepods of the genus Anthessius from the northeastern Pacific Ocean. Pac. Sei., 14: 337-372. Stock, J. H., A. G. Humes & R. U. Gooding, 1963. Copepods associated with West Indian invertebrates, 3. The genus Anthessius (Cyclopoida, Myicolidae). Stud. Fauna Cura?ao, 17: 1-37. Received for publication 7 May 1980. NOTES ON RECENT CHANGES IN TANAIDACEAN TERMINOLOGY BY CHARLES GARRETT MESSING Division of Echinoderms, National Museum of Natural History, Washington, D.C. 20560, U.S.A. Although tanaidacean terminology achieved a measure of stability through the work of Lang (e.g., 1953a) and Wolff (1956), several changes have recently been made, primarily by Sieg (1973, 1977), that deserve comment. C?phalothorax versus carapace. ? Sieg uses c?phalothorax in place of the widely accepted carapace. He follows Zimmer (1927) in defining Crustaceana 41 (1) 1981, E. J. Brill, Leiden This content downloaded from 137.52.76.29 on Thu, 12 Jun 2014 14:57:22 PMAll use subject to JSTOR Terms and ConditionsNOTES AND NEWS 97 c?phalothorax as the anterior chitinous case (Chitinkapsel) formed by fusion of the head with one or more thoracic segments and restricting the term carapace to the chitinous fold (Chitinduplicatur) arising from the posterior margin of the head. Although I agree that c?phalothorax may be a more appropriate term for the anterior tagma, including internal components, taxonomic descriptions generally only refer to the external covering of the anterior tagma. Although carcinologists acknowledge the embryological origin of the malacostracan carapace as a postmaxillary fold (e.g., Mant?n, 1977), for descriptive purposes, a distinction is rarely drawn between the free fold and the cephalic and thoracic tergites with which it is fused; the practical definition refers to the entire shieldlike structure except the rostrum (Caiman, 1909; Waterman & Chace, 1960; Moore & McCormick, 1969) or, even more simply, the external covering of the c?phalothorax (Stebbing, 1893; Snodgrass, 1938). In addition, the concept of c?phalothorax as incorporating one or more thoracic segments has sometimes been considered too diffuse. Waterman & Chace (1960) and Hessler & Rolfe (1969) restrict its use to the unit formed by fusion of the head with the entire thorax. The latter authors have also proposed the term gnathothorax to refer to cases in which "not all thoracic segments become fused, and the limbs of those that do become modified as mouthparts or for food capture." In rejecting the use of carapace for the entire cephalothoracic shield, Sieg states that the free carapace fold (Zimmer's carapace) is small in tanaidaceans and encloses only small respiratory chambers and cites Dennell (1937) for the information. Dennell, however, states that the carapace is small in relation to the entire animal, only two thoracic segments being incorporated. The struc ture is certainly not significantly smaller than in some cumaceans in which three thoracic segments are incorporated. Dennell's figure (1937: 66, fig. 6), although indicating that the branchial chambers are partly filled by chelipedal coxae and associated muscles, illustrates that the free carapace folds are as ex tensive in transverse section as in many decapods (see, for example, Kaestner, 1970; Huxley, 1937). In monokonophoran tanaidaceans that I have examined (species of Apseudes, Kalliapseudes and Pagurapseudes), the free carapace fold occupies most of the posterior half of the unit formed by fusion of the head and anterior two thoracic segments. Even in the dikonophoran Neotanais, which has large, lateral, chelipedal coxae, the free fold is extensive. Thus, in the context of descriptive taxonomy, because reference is generally made to the external, shieldlike covering of the anterior tagma rather than the tagma itself and because the structure is basically similar in tanaidaceans, cumaceans, mysidaceans, hoplocaridans and eucaridans, the term carapace should be retained. Limits of the pereon. ? Sieg (1973, 1977) also suggests that the pereon cor rectly begins with the first free thoracic segment and that the thoracic appen This content downloaded from 137.52.76.29 on Thu, 12 Jun 2014 14:57:22 PMAll use subject to JSTOR Terms and Conditions98 NOTES AND NEWS dages should be labelled maxilliped, cheliped, pereopods I-VI, rather than the system in current use [maxilliped, cheliped ( = pereopod I), pereopods II-VII] (e.g., Lang, 1973; Gardiner, 1975). As Wolff (1956, 1962) noted, Bate (1856) introduced the term in his treatment of amphipods: "Thoracic segments (Pereion*). The seven annules which posteriorly follow the cephalic portion are in the higher order protected by the carapace... in the Amphipoda each segment is formed into a perfect ring,.." Subsequently, Bate took part in describing the genus Tanais as having the "Cephalon and first segment of pereion confluent" (Bate & Westwood, 1868). Similarly, the first pereonite is almost completely fused with the "cephalon" (head plus first thoracic seg ment) in many caprellid amphipods. Sieg's contention that the pereon is com posed only of free thoracic segments (1973: 10) is, therefore, not justified. Although Bate's interpretation of the Greek word from which he derived the term pereon ("From negatou, to walk about: pereion, part which supports the walking legs") suggests that his emphasis was on the locomotory nature of the appendages, thereby strengthening Sieg's position, Bate also wrote of the two anterior "pereipoda": "the probability is that they are never used except as supplying organs to the mouth, unless to assist in climbing occasionally" (Bate, 1856: 27). These supposedly non-locomotory pereopods became known as gnathopods although they remained attached to the pereon (Bate, 1856: pi. 16). As a result, the third pereonite was said to bear the first pereopod, an un fortunate practice that was followed for a while in tanaidacean taxonomy (Bate & Westwood, 1868; Norman & Stebbing, 1886) but has persisted in amphipod taxonomy (Barnard, 1969), though not universally (Chevreux & Fage, 1925; McCain, 1968; Bousfield, 1973). Alternatively, all thoracic appendages may be called thoracopods, thus avoiding problems in both the use and spelling (not treated here) of pereon. Of course, one must remember that the posterior limit of the malacostracan head, although generally and for a long time recognized as the posterior margin of the second maxillary somite, is also an arbitrary demarcation (Snodgrass, 1938). Use of the terms legs or walking legs is purely a functional reference and carries no pretense of indicating homology. Nature and enumeration of manca instars. ? Zimmer (1926: 58) was the first to use the term manca to designate a developmental stage: "Bekanntlich verlassen die Cumaceen das m?tterliche Marsupium in einem Zustand, worin ihnen der letzte Cormopod fehlt. Ich bezeichne dieses Stadium als manca Stadium (nach Diastylis manca, G. O. Sars, wo dem Typus offenbar als Neotenie gleichfalls der letzte Cormopod fehlt)." ["As is known, the Cumacea leave the maternal marsupium in a condition in which the last cormopod ( = pereopod) is absent. I name this stage the manca-stage (after Diastylis manca, G. O. Sars, in which the type, evidently neotenic, likewise lacks the last cormopod)."] This content downloaded from 137.52.76.29 on Thu, 12 Jun 2014 14:57:22 PMAll use subject to JSTOR Terms and ConditionsNOTES AND NEWS 99 In outlining the development of the dikonophoran Heterotanais oerstedii (Kroyer), Buckle-Ramirez (1965) designated animals that had just hatched but had yet to develop considerably before leaving the marsupium as the first of three manca stages. He characterized this first stage by lecithotrophy, incomplete segmentation and a thinly chitinized integument. Thus defined, however, it is structurally and functionally closer to the late, pre-hatching em bryo than to the newly released manca (his manca 2). In fact, the manca 1 stage of H. oerstedii, by B?ckle-Ramirez' definition (followed by Sieg, 1972, 1978), corresponds with the third embryonic stage of the isopody^ra albifrons Leach as described by Forsman (1944). The lecithotrophic hatchling differs enough from the newly released manca to warrant some distinction. However, because it is unknown if loss of lecithotrophy and completion of segmentation occur in concordance and, more importantly, because no ecdysis separates the two "stages," such a clear distinction as manca 1-manca 2 should not be applied. Either the lecithotrophic hatchling should be called just that or, as suggested by L. B. Holthuis (per sonal communication), it could be considered as an early stage of development of the manca 1 instar. In either case, B?ckle-Ramirez' manca 2 is actually the first true manca (see also Gardiner, 1975). The instar following the manca 1 (my usage) in tanaidaceans bears rudimen tary pereopods VII and may or may not bear rudimentary pleopods. This is the second and last manca instar (manca 3 of B?ckle-Ramirez, 1965, and Sieg, 1972, 1978). Although Gardiner (1975) used these designations, in an earlier paper (1973) he referred to a specimen with rudimentary pereopods VII as a manca 1 and thus did not differentiate between juveniles and mancas 2. The very small specimen with genital cones that he called a manca 2 is actually an immature male. The practice of calling the instar with rudimentary pereopods VII a manca as well as that lacking any trace of these appendages apparently began with Forsman (1944) and is now widely followed (Lang, 1953b; Wolff, 1956, 1962; Hessler, 1970; Gardiner, 1975) although such a stage was not originally recognized in the Cumacea (Zimmer, 1926). Acknowledgements. ? I would like to thank T. E. Bowman, F. A. Chace, L. B. Holthuis, B. Kensley, P. A. McLaughlin, H. B. Michel, L. Watling and A. B. Williams for their most helpful assistance and comments. This is a contribution from the University of Miami, Rosenstiel School of Marine and Atmospheric Science, 4600 Rickenbacker Causeway, Miami, Florida 33149 U.S.A. LITERATURE CITED Barnard, J. L., 1969. The families and genera of marine gammaridean Amphipoda. Bull. U.S. natl. Mus., 271: i-vi, 1-535. Bate, C. S., 1856. On the British Edriophthalma. Brit. Assoc. Adv. Sei. Rep., 1855: 18-62. This content downloaded from 137.52.76.29 on Thu, 12 Jun 2014 14:57:22 PMAll use subject to JSTOR Terms and Conditions100 NOTES AND NEWS Bate, C. S. & J. O. Westwood, 1868. A history of British sessile-eyed Crustacea, 2: i-lvi, 1-536. (J. van Voorst, London). Bousfield, E. L., 1973. Shallow-water gammaridean amphipods of New England: i-xiv, 1-312. (Cornell Univ. Press). B?ckle-Ramirez, L. F., 1965. Untersuchungen ?ber die Biologie von Heterotanais oerstedii (Krayer). Zeitschr. Morphol. ?kol. Tiere, 55(6): 714-782. Calman, W. T., 1909. Crustacea. In: R. Lankester, A. treatise on zoology, 7(3): i-viii, 1-346. (Adam & Black, London). Chevreux, E. & L. Fage, 1925. Amphipodes. Faune de France, 9: 1-488, figs. 1-438. Dennell, R., 1937. On the feeding mechanism of Apseudes talpa, and the evolution of the pericaridan feeding mechanism. Trans, roy. Soc. Edinburgh, 59(1): 57-78. Forsman, B., 1944. Beobachtungen ?ber Jaera albifrons Leach an der schwedischen Westk?ste. Ark. Zool., 35A(11): 1-33, 1 pi. Gardiner, L. F., 1973. New species of the genera Synapseudes and Cyclopoapseudes with notes on morphological variation, postmarsupial development, and phylogenetic relationships within the family Metapseudidae (Crustacea: Tanaidacea). Zool. Journ. Linn. Soc. London, 53(1): 25-58. -, 1975. The systematics, postmarsupial development and ecology of the deep-sea family Neotanaidae (Crustacea: Tanaidacea). Smithson. Contrib. Zool., 170: i-iv, 1-265. Hessler, R. R., 1970. The Desmosomatidae (Isopoda, Asellota) of the Gay Head-Bermuda Transects. Bull. Scripps Inst. Oceanog., 15: i-vi, 1-185. Hessler, R. R. & W. D. Rolfe, 1969. Note. In: R. C. Moore (ed.), Treatise on invertebrate paleontology, (R. Arthropoda) 4(1): R 93. Huxley, T. H., 1973. The crayfish. An introduction to the study of zoology: i-xxviii, 1-371 (M. I. T. Press). Kaestner, A., 1970. Invertebrate zoology, 3 (Crustacea): i-xii, 1-523. (Interscience). Lang, K., 1953a. Apseudes hermaphroditicus n. sp. A hermaphroditic tanaid from the Ant arctic. Ark. Zool., (2) 4(18): 341-350. -, 1953b. The postmarsupial development of the Tanaidacea. Ark. Zool., (2) 4(24): 409-422, pis. 1-4. -, 1973. Taxonomische und phylogenetische Untersuchungen ?ber die Tanaidaceen (Crus tacea). 8. Die Gattungen Leptochelia Dana, Paratanais Dana, Heterotanais G. O. Sars und Nototanais Richardson. Dazu einige Bemerkungen ?ber die Monokonophora und ein Nachtrag. Zool. Scripta, 2: 197-229. Mant?n, S. M., 1977. The Arthropoda: i-xxii, 1-527 (Clarendon Press, Oxford). McCain,J.C, 1968. TheCaprellidae(Crustacea:Amphipoda)ofthewesternNorthAtlantic. Bull. U.S. natl. Mus., 278: i-vi. 1-147. Moore, R. C. & L. McCormick, 1969. General features of Crustacea. In: R. C. Moore (ed.), Treatise on invertebrate paleontology, (R, Arthropoda) 4(1): R57-R120. Norman, A. M. & T. R. R. Stebbing, 1886. On the Crustacea Isopoda of the "Lightning," "Porcupine" and "Valorous" expeditions. Trans, zool. Soc. London, 12(4): 77-141. Sieg, J., 1972. Untersuchungen ?ber Tanaidaceen, 1. Bemerkungen ?ber die postmarsupiale Entwicklung der Tanaidaceen. Kieler Meeresforsch., 28(2): 232-236. -, 1973. Ein Beitrag zur nat?rlichen System der Dikonophora Lang (Crustacea, Tana idacea). Doct. Diss. Christian Albrechts Univ., Kiel: i-iv, 1-298, pis. 1-235. -, 1977. Taxonomische Monographie der Familie Pseudotanaidae (Crustacea, Tanaidacea). Mitt. zool. Mus. Berlin, 53(1): 3-109. -, 1978. Bemerkungen zur M?glichkeit der Bestimmung der Weibchen bei den Dikonophora und der Entwicklung der Tanaidaceen. Zool. Anz., 200(3/4): 233-241. Snodgrass, R. E., 1938. Evolution of Annelida, Onychophora and Arthropoda. Smithson. misc. Coll., 97(6): 1-159. Stebbing, T. R. R., 1893. A history of Crustacea, recent Malacostraca. Internat, sei. Ser., 74: i-xvii, 1-466, pis. 1-19. (Kegan Paul, Trench, Tr?bner Co., London). Waterman, T. H. & F. A. Chace, 1960. General crustacean biology. In: T. H. Waterman (ed.), The physiology of Crustacea, 1: 1-33. (Academic Press). Wolff, T., 1956. Crustacea Tanaidacea from depths exceeding 6000 m. Galathea Rep., 2: 187-241. This content downloaded from 137.52.76.29 on Thu, 12 Jun 2014 14:57:22 PMAll use subject to JSTOR Terms and ConditionsNOTES AND NEWS 101 -, 1962. The systematics and biology of bathyal and abyssal Isopoda Asellota. Galathea Rep., 6: 1-320, pis. 1-19. Zimmer, C, 1926. Northern and arctic invertebrates in the collection of the Swedish State Museum, 10. Cumaceen. Kungl. Svensk. Vetensk. Akad. Handl., 3(2): 1-88, pis. 1-4. -, 1927. Crustacea. In: W. K?kenthal & T. Krumbach, Handbuch der Zoologie, 3: 277 304. (De Gruyter and Co., Berlin). Received for publication 21 May 1980. OPPORTUNISTIC FEEDING BEHAVIOUR IN A PREDATORY ISOPOD BY D. M. HOLDICH Department of Zoology, The University, Nottingham, NG7 2RD, England Introduction. ? Isopods of the family Cirolanidae are well known as active predators (Dahl, 1952; Johnson, 1976) but opportunistic feeding also plays a part in their feeding behaviour (Johnson, 1976). Examination of the gut con tents of littoral species has revealed the presence of many different marine food items (Jones, 1968; Johnson, 1976) but there are few records of the remains of terrestrial arthropod material in the gut. The observations described below show that such elements of the fauna may form a substantial food source for Eurydice affinis Hansen when the opportunity arises. This isopod is a common predator on beaches in S.W. England and S.W. France (Jones, 1967; Salvat, 1966). Observations. ? The warm period of weather over most of the British Isles in early April, 1980 prompted the emergence of many different species of insect. On the north coast of Cornwall many living insects, and some arachnids, were found floating on the surface of the incoming tide and others were found on the surface of pools on rocky shores. At Trevone (S.W. 888759) Eurydice affinis is found inhabiting fairly coarse sand on the exposed beaches. Individuals often get stranded in pools on the nearby rocky shores when the tide ebbs. On a day-time low spring tide a large number (50 + ) of E. affinis were seen swimming in an apparently random manner just below the surface of a large mid-tidal pool measuring 5 m by 8 m in area and 3 m in depth. The isopods were actively feeding on dipteran, coleopteran and hemipteran insects which were trapped in the surface film of the pool. The isopods did not take their prey below the water but attacked them from below, grasping them with their pereopods and feeding on them for a few minutes whilst propelling them around the pool's surface. They then let go and swam randomly around the pool until they either collided with another food item or viewed it from below. Crustaceana 41 (1) 1981, E. J. Brill, Leiden This content downloaded from 137.52.76.29 on Thu, 12 Jun 2014 14:57:22 PMAll use subject to JSTOR Terms and Conditions

Notes on Recent Changes in Tanaidacean Terminology

http://nsuworks.nova.edu/cgi/viewcontent.cgi?article=1125&context=occ_facarticles

Notes on Recent Changes in Tanaidacean Terminology

Abstract

Similar works

Full text

Available Versions

NSU Works