GRBQ188-2777G-CH27[411-693].qxd 5/3/07 05:38 PM Page 545 Techbooks (PPG Quark) Dojiri, M., and J. Sieg, 1997. The Tanaidacea, pp. 181–278. In: J. A. Blake stranded medusae or salps. The Gammaridea (scuds, land- and P. H. Scott, Taxonomic atlas of the benthic fauna of the Santa hoppers, and beachhoppers) (plate 254E) are the most abun- Maria Basin and western Santa Barbara Channel. 11. The Crustacea. dant and familiar amphipods. They occur in pelagic and Part 2 The Isopoda, Cumacea and Tanaidacea. Santa Barbara Museum of Natural History, Santa Barbara, California. benthic habitats of fresh, brackish, and marine waters, the Hatch, M. H. 1947. The Chelifera and Isopoda of Washington and supralittoral fringe of the seashore, and in a few damp terres- adjacent regions. Univ. Wash. Publ. Biol. 10: 155–274. trial habitats and are difficult to overlook. The wormlike, 2- Holdich, D. M., and J. A. Jones. 1983. Tanaids: keys and notes for the mm-long interstitial Ingofiellidea (plate 254D) has not been identification of the species. New York: Cambridge University Press. reported from the eastern Pacific, but they may slip through Howard, A. D. 1952. Molluscan shells occupied by tanaids. Nautilus 65: 74–75. standard sieves and their interstitial habitats are poorly sam- Lang, K. 1950. The genus Pancolus Richardson and some remarks on pled. Paratanais euelpis Barnard (Tanaidacea). Arkiv. for Zool. 1: 357–360. Lang, K. 1956. Neotanaidae nov. fam., with some remarks on the phy- logeny of the Tanaidacea. Arkiv. for Zool. 9: 469–475. Key to Amphipoda Lang, K. 1961. Further notes on Pancolus californiensis Richardson. Arkiv. for Zool. 13: 573–577. 1. Gills not exceeding three pairs, female oöstegites not ex- Larsen, K. and G. D. F. Wilson. 2002. Tanaidacean phylogeny, the first step: the superfamily Paratanaidoidea. J. Zool. Syst. Evol. Res. 40: 205–222. ceeding two pairs; pleon and urosome (abdomen) vestig- Lee, W. L., and M. A. Miller. 1980. Isopoda and Tanaidacea: the isopods ial and pereonite 1 fused to head...................2 and allies. In Intertidal invertebrates of California. pp. 536–558. R. — Gills and oöstegites exceeding three pairs, abdomen and ab- H. Morris, D. P. Abbott, and E. C. Haderlie, eds. pp. 536-558. Stan- dominal appendages well developed; head and pereonite 1 ford, CA: Stanford University Press, 690 pp. separate .......................................3 Menzies, R. J. 1949. A new species of Apseudid crustacean of the genus Synapseudes from northern California (Tanaidacea). Proc. U.S. Natl. 2. Body segments tubular, legs with moderate hooks, free liv- Mus. 99: 509–515. ing (plate 254A) ........................Caprellidae Menzies, R. J. 1953. The Apseudid Chelifera of the eastern tropical and — Body segments loosely separated, legs powerful with sharp north temperate Pacific Ocean. Bull. Mus. Comp. Zool. 107: 443–496. hooks, parasites of cetaceans (plate 254B) .....Cyamidae Miller, M. A. 1940. The isopod Crustacea of the Hawaiian Islands (Che- 3. Urosome with only two segments; palps of maxillipeds ab- lifera and Valvifera). Occ. Pap. Bernice P. Bishop Mus. 15, no. 26, pp. 299–321. sent; eyes usually cover most of head but can be tiny; en- Miller, M. A. 1968. Isopoda and Tanaidacea from buoys in coastal wa- tirely pelagic (plate 254C) .................Hyperiidea ters of the continental United States, Hawaii, and the Bahamas (Crus- — Urosome with three segments; palps of maxillipeds present tacea). Proc. U.S. Natl. Mus. 125: 1–53. ..............................................4 Richardson, H. 1905a. Descriptions of a new genus of Isopoda belong- 4. Pleopods leaflike, vestigial, or absent; movable compound ing to the family Tanaidae and of a new species of Tanais, both from Monterey Bay, California. Proc. U.S. Natl. Mus. 28: 367–370. claw of gnathopods formed of articles 6 and 7 together; Richardson, H. 1905b. A monograph on the isopods of North America. body vermiform; without coxal and epimeral plates; en- Washington, D.C. Smithsonian Institution, 727 pp. tirely interstitial (unreported from the northeast Pacific) Sieg, J. 1980. Taxonomische Monographie der Tanaidae Dana, 1849 (plate 254D) ..........................Ingolfiellidea (Crustacea: Tanaidacea). Abhandlungen Senckenbergische Natur- — Pleopods well developed, with few exceptions; dactyls of forschende Gesellschaft 537: 1–267. Sieg, J. 1986. Distribution of the Tanaidacea: Synopsis of the known data gnathopods formed by article 7 alone (plate 254E)...... and suggestions on possible distribution patterns, pp. 165–193. In: .....................................Gammaridea Crustacean Issues, vol. 4, Crustacean Biogeography, F. R. Schram, ed., Balkema, Rotterdam, The Netherlands. Sieg, J., and R. N. Winn. 1979. Keys to suborders and families of Gammaridea Tanaidacea (Crustacea). Proc. Biol. Soc. Wash. 91: 840–846. Sieg, J., and R. N. Winn. 1981. The Tanaidae (Crustacea; Tanaidacea) of JOHN W. CHAPMAN California, with a key to the world genera. Proc. Biol. Soc. Wash. 94: 315–343. (Plates 255–304) The ubiquitous and abundant gammaridean amphipods are critically important in marine and estuarine shallow-water Amphipoda ecosystems of the northeast Pacific and warrant reliable, work- able guides to the species. The numerical abundances and (Plate 254) species and life-history diversities of the Gammaridea exceed The Amphipoda have been divided into the suborders Gam- all other eucaridan or peracaridan orders. Gammaridean am- maridea, Caprellidea, Cyamidea, Hyperiidea and Ingolfiel- phipods are one of the most common aquatic taxa. The tax- lidea (Schram 1986, Crustacea. Oxford University Press, New onomy and systematics of marine eastern Pacific species have York). However, Myers and Lowry (2003) regard the caprel- greatly advanced since 1975, but many undescribed species oc- lids, or skeleton shrimps, and the cyamids, or whale lice, as cur in the region and little more than the names of most described families Caprellidae and Cyamidae. These distinctive groups species are known. The lack of research is disproportionate to are covered in separate sections in this manual, for ease of these species’ importance in ecosystems that are of great interest recognition and identification. to humans. The Caprellidae (plate 254A) occur on solid surfaces and are Gammaridean amphipods are critical food sources of strictly marine or estuarine. The Cyamidae are ectoparasites of whales, fish, and birds, (Moore et al. 2003, McCurdy et al. 2005, cetaceans and are occasionally found on beached whales and Schneider and Harrington 1981) and are highly sensitive to dolphins (plate 254B). The Hyperiidea (plate 254C) are para- environmental alterations (Conlan 1994, Zajac et al. 2003). sites and commensals of marine macrozooplankton and are All amphipods care for their offspring for extended periods exclusively pelagic. Hyperiids are occasionally discovered free (Jones 1971, Shillaker and Moore 1987). Some change sex swimming intertidally or in shallow-water plankton tows, or (Lowry and Stoddart 1986); others attract, hold, and defend are found attached beneath or embedded in the bells of mates (Borowsky1983, 1984, 1985; Conlan 1989, 1995a) and AMPHIPODA: GAMMARIDEA 545 GRBQ188-2777G-CH27[411-693].qxd 5/3/07 05:38 PM Page 546 Techbooks (PPG Quark) PLATE 254 Amphipoda. A, Caprellidae—Caprella mutica; B, Cyamidae—Cyamus scammoni; C, Hyperiidea—Hyperoche medusarum (Müller, 1776) in situ; D, Ingolfiellidea—Ingolfiella fuscina Dojiri and Seig, 1987; E, Gammaridea—generalized body; F, G, generalized upper lip; H, generalized mandible; I, generalized head; J, generalized lower lip; K, generalized maxilla 1; L, generalized maxilla 2; M, Polycheria mandible; N, generalized maxilliped; O, uropod 1, Paragrubia uncinata; P, telson, Eohaustorius; Q, telson, Batea lobata; R, telson, Parallorchestes leblondi; S, telson, Stenothoe estacola; T, telson, Paracorophium sp.; U, gnathopod 1, Aoroides secundus; V, gnathopod 2, Ericthonius brasiliensis; W, gnathopod 1, Americhelidium shoemakeri; X, gnathopod 2, Americhelidium rectipalmum; Y, gnathopod 1, Stenothoe valida (figures modified from: Barnard 1953,1962c, 1965, 1975; Barnard and Karaman 1991a, 1991b; Bousfield 1973; Bousfield and Chevrier 1996; Bousfield and Hendrycks 2002; Bousfield and Kendall 1994; Doiji and Sieg 1987, Flores and Brusca 1975; Gurjanova 1938; Margolis et al. 2000; Todd Miller, personal communication; and Platovoet et al. 1995). GRBQ188-2777G-CH27[411-693].qxd 5/3/07 05:38 PM Page 547 Techbooks (PPG Quark) territories (Connell 1963). Some use chemicals for defense bathymetric, or ecological boundaries. Barnard’s (1975) em- (Hay et al. 1987, Hay et al. 1990) or are repelled by defensive phasis on durable and external morphology is followed with chemicals (Hay et al. 1988, 1990; Cronin and Hay 1996a, “natural” dichotomies sacrificed when artificial distinctions are 1996b). Some species undergo risky long-distance migrations more apparent, where family, genus, or species relationships re- (Chess 1979, Mills 1967, Watkin 1941), and others exploit, main poorly resolved, where difficult dissections or magnifi- imitate, parasitize, eat (Crane 1969, Cartwright and Behrens cations of greater than 40x can be avoided, or where characters 1980, Goddard, Skogsberg, and Vansell 1928), displace, or at- are fragile or difficult to observe or to define. Occasional notes tack other invertebrates and fish (Bousfield 1987, Wilhelm in the species lists are to assist with identifications, indicate pit- and Schindler 1999); burrow in wood (Barnard 1955c) or falls, or provoke interest. macroalgae