Cancer Antennarius Class: Multicrustacea, Malacostraca, Eumalacostraca

Phylum: Arthropoda, Crustacea

Cancer antennarius Class: Multicrustacea, Malacostraca, Eumalacostraca

Order: Eucarida, Decapoda, Pleocyemata, Brachyura, The ghost shrimp Eubrachyura, Heterotremata Family: Cancroidea, Cancridae

Taxonomy: The most recent taxonomic de- ages including one pair of mandibles (on ei- bate regards this species being placed in the ther side of the mouth), two pairs of maxillae recently elevated genus, Romaleon and three pairs of maxillipeds. The maxillae (Schweitzer and Feldmann 2000). However, and maxillipeds attach posterior to the mouth molecular work does not always support the and extend to cover the mandibles (Ruppert monophyly of this or other cancrid genera et al. 2004). Merus of third maxillipeds with (Harrison and Crespi 1999). Although many distal margin and rounded angles in C. anten- researchers have switched to the name R. narius (Wicksten 2011). antennarius (or R. antennarium) (e.g., Carapace: Oval and widest at eighth Wicksten 2011), we follow the most current tooth. Antero-lateral and postero-lateral mar- local intertidal guide that retains the name gins meet at distinct angle. Carapace surface Cancer antennarius (Kuris et al. 2007). lumpy, uneven and finely granulated (Fig. 1). Frontal Area: Frontal area not pro- Description duced with five medial (three central) teeth, of Size: Females up to 148 mm in carapace which the outer pair is the largest, center width and males 178 mm (Puls 2001). Type tooth small (Fig. 2) (Kuris et al. 2007; Wick- specimen carapace is 118 mm in width sten 2011). (Rathbun 1930). Teeth: 11 antero- and post-lateral Color: Reddish color dorsally, light yellow teeth are curved forward (Fig. 2). ventrally with red spots, especially frontally Pereopods: Walking legs rough and (Ricketts and Calvin 1971). Chelae dactyls hairy. Dactyls with five longitudinal rows of dark (Wicksten 2011) (Fig. 1). bristles (Rathbun 1930). General Morphology: The body of decapod Chelipeds: Chelae heavy, nearly crustaceans can be divided into the cepha- smooth and black-tipped. Inner carpus (wrist) lothorax (fused head and thorax) and abdo- with single sharp spine. Chelipeds can be men. They have a large plate-like carapace slightly unequal in size (Wicksten 2011). dorsally, beneath which are five pairs of tho- Abdomen (Pleon): Abdomen narrow in male, racic appendages (see chelipeds and pere- broad in female (e.g. see Cancer magister, opods) and three pairs of maxillipeds (see Fig. 3). mouthparts). The abdomen and associated Telson & Uropods: appendages are reduced and folded ventral- Sexual Dimorphism: Male and female brach- ly (Decapoda, Kuris et al. 2007). yuran crabs are easily differentiated. The Cephalothorax: most conspicuous feature, the abdomen, is Eyes: Eyestalks short, orbits small. narrow and triangular in males while it is wide Eyes are frontal with a small supra-orbital and flap-like in females. Additionally, males tooth (Fig. 1). have one large chelae and two pleopod pairs Antenna: specialized for copulation however, the third Mouthparts: The mouth of decapod and fourth pleopods are absent. Females, on crustaceans comprises six pairs of append-

A publication of the University of Oregon Libraries and the Oregon Institute of Marine Biology Individual species: https://oimb.uoregon.edu/oregon-estuarine-invertebrates and full 3rd edition: http://hdl.handle.net/1794/18839 Email corrections to: [email protected]

Hiebert, T.C. 2015. Cancer antennarius. In: Oregon Estuarine Invertebrates: Rudys' Illustrated Guide to Common Species, 3rd ed. T.C. Hiebert, B.A. Butler and A.L. Shanks (eds.). University of Oregon Libraries and Oregon Institute of Marine Biology, Charleston, OR.

the other hand, have all four pleopod pairs, Wicksten 2011). Cancer branneri is a small each with long setae for egg attachment species (35 mm) that is rare intertidally and (Brachyura, Kuris et al. 2007). recognizable by cheliped dactyls that are long, straight, black and spiny. Cancer graci- Possible Misidentifications lis (27 mm) has white-tipped cheliped dactyls According to some authors, the ge- and C. jordani (25 mm) has a hairy carapace nus Cancer comprises 23 species (Harrison and sharp curving teeth. Cancer anthonyi, and Crespi 1999 but see Schweitzer and the yellow rock crab, is larger than the pre- Feldmann 2000). This genus is vious three at 52 mm and has black-tipped differentiated from other brachyuran genera cheliped dactyls (Kuris et al. 2007; Wicksten by the broadly oval carapace, presence of 2011). Populations of C. productus, C. ant- five frontal teeth and antennules that fold honyi (southern California) and C. magister back over carapace. Characters unique to support commercial fisheries (Kuris et al. Cancer antennarius include 11 antero- 2007). Cancer antennarius is a common lateral teeth, carapace widest at 8 tooth, species used in biochemistry and physiology red color, black-tipped cheliped dactyls and studies (e.g. Spaziani et al. 1997; Kang and small size (Kuris et al. 2007). Cancer an- Spaziani 1996; Rudolph and Spaziani 1991). tennarius is smaller than most of the other adult Cancer species. In color, C. Ecological Information productus is most similar to C. antennarius Range: Type locality is San Francisco. (dark red, black-tipped chelae), but never Known range includes British Columbia, Can- has red spots on its underbody, though its ada to Baja, California. Not common in Puget legs may be mottled. They also occur in Sound. the same ecological niches. Furthermore, Local Distribution: In Coos Bay (and proba- C. productus has ten teeth (not 11). bly other Oregon estuaries) individuals are Cancer antennarius is also smaller than C. most common on protected outer coast. productus, and lacks its obviously Habitat: Often buried in the sand and under pronounced frontal area. rocks (Ricketts and Calvin 1971). There are eight Cancer species Salinity: In San Francisco, found at salinities known locally (Kuris et al. 2007). Cancer ranging from 26.6 to 33.3 (Schmitt 1921). magister (adults at least 30 mm in width), Cancer antennarius cannot tolerate brackish C. productus (adults over 20 mm in width) conditions and cannot osmoregulate (Garth and C. antennarius (adults typically 100 mm and Abbott 1980). in width) are the largest species. Cancer Temperature: In San Francisco Bay, productus and C. magister have 10 antero- individuals collected at 8.7–14.3° C (Schmitt lateral teeth and five subequal frontal teeth 1921). (Kuris et al. 2007). The carapace of C. Tidal Level: Occurs in lower tide pools magister is widest at the tenth tooth, is (Ricketts and Calvin 1971) and subtidally to more subtly pigmented and does not have 91 m (Kittredge et al. 1971; Puls 2001). black tipped dactyls seen in C. productus Associates: Often encrusted with poly- (Schmitt 1921; Kuris et al. 2007; Wicksten chaetes (family Iphitimidae) in branchial cavi- 2011). ties (southern California) (Kuris et al. 2007). The remaining four species tend to Abundance: Common in California and Ore- be smaller and have nine antero-lateral gon, becomes rarer farther north. teeth (sometimes ten in older specimens, Life-History Information

Reproduction: Mating occurs when the fe- days, which is shorter than observed for C. male is about to molt, male C. antennarius magister or C. productus (Roesijadi 1976). clasp females several days prior to molting Juvenile: Juvenile C. antennarius may have and copulation takes place after molting oc- second small spine on carpus. Their cara- curs. In the lab, males were stimulated to pace is widest at the ninth tooth, the tenth pre-mating behavior by the release of a (and last) tooth is prominent and shiny. Cara- molting hormone by Pachygrapsus pace is crowded with granules. The manus of crassipes (Kittredge et al. 1971). Fertiliza- cheliped are light in color, fingers (dactyls) tion is internal, occurs after molting and egg bear dark pigment and extreme tips are light deposition occurs months later (November– in color. Legs may bear more setae than is January, Ricketts and Calvin 1971). seen in adult individuals (Wicksten 2011). Females with eggs were encountered in Longevity: Humboldt Bay, California in April (Puls Growth Rate: Growth occurs in conjunction 2001). All decapod crustacean females with molting. In pre-molting periods the epi- attach recently laid gelatinous egg masses dermis separates from the old cuticle and a to their pleopods. The outer embryo dramatic increase in epidermal cell growth oc- membrane thickens and a strand develops curs. Post-molt individuals will have soft that attaches each embryo to pleopod setae shells until a thin membranous layer is depos- (Decapoda, Kuris et al. 2007). ited and the cuticle gradually hardens. During Larva: The larvae of C. antennarius were a molt decapods have the ability to regener- described by Roesijadi (1976). Larval devel- ate limbs that were previously autotomized opment proceeds via a series of zoea (five (Kuris et al. 2007). total, telson with single lateral spine at each Food: A scavenger and predator, particularly fork, Lough 1975) and megalopae stages, of hermit crabs (Garth and Abbott 1980). each marked by a molt (Roesijadi 1976). Predators: Octopuses, sea otters and occa- Cancer antennarius zoea are planktotrophic sionally harvested by sport fishermen. Larvae and have large compound eyes and four are preyed upon by plankton feeders (herring, spines: one each dorsal and rostral and two salmon, etc.). lateral (Fig. 3b) (see Fig. 4, Roesijadi 1976; Behavior: Puls 2001; Martin 2014). Larval size Bibliography (measured from tip of rostrum to tip of telson) proceeds from 1.8 mm (Zoea I) to 4.4 1. GARTH, J. S., and D. P. ABBOTT. 1980. mm (Zoea V) (Puls 2001). Megalopae are Brachyura: the true crabs, p. 594-630. In: 2.3–3.3 mm from rostrum tip to posterior Intertidal invertebrates of California. R. H. carapace and 1.4–2.4 mm in width. The Morris, D. P. Abbott, and E. C. Haderlie megalopae bear one stout spine on ischi- (eds.). Stanford University Press, Stan- opodite of cheliped and exhibit similar mor- ford, CA. phology to the larvae of C. gracilis (Puls 2. HARRISON, M. K., and B. J. CRESPI. 2001). The larvae of cancrid species are 1999. Phylogenetics of Cancer crabs difficult to distinguish, especially the prezoe- (Crustacea : Decapoda : Brachyura). Mo- al stages (Fig. 3a), but the zoea and mega- lecular Phylogenetics and Evolution. lopae of C. antennarius are smaller and pos- 12:186-199. sess fewer setae than other species. In lar- 3. KANG, B. K., and E. SPAZIANI. 1996. Up- vae reared at 13.8˚C, hatching from the fifth take of high-density lipoprotein by Y- zoeal stage to the megalopa occurred at 36 organs of the crab, Cancer antennarius. 1.

Characterization in vitro and effects of 12. RUDOLPH, P. H., and E. SPAZIANI. stimulators and inhibitors. Archives of 1991. Neurons demonstrable by nickle ly- Insect Biochemistry and Physiology. sine backfilling of the optic peduncle in the 31:106-106. crab Cancer antennarius. Comparative Bi- 4. KITTREDGE, J. S., M. TERRY, and F. T. ochemistry and Physiology C- TAKAHASHI. 1971. Sex pheromone ac- Pharmacology Toxicology & Endocrinolo- tivity of the molting hormone, crustecdy- gy. 99:179-184. sone, on male crabs (Pachygrapsus 13. RUPPERT, E. E., R. S. FOX, and R. D. crassipes, Cancer antennarius, and C. BARNES. 2004. Invertebrate zoology: a anthonyi). Fishery Bulletin. 69:337-343. functional evolutionary approach. Thom- 5. KURIS, A. M., P. S. SADEGHIAN, J. T. son Brooks/Cole, Belmont, CA. CARLTON, and E. CAMPOS. 2007. De- 14. SCHMITT, W. L. 1921. The marine deca- capoda, p. 632-656. In: The Light and pod crustacea of California. University of Smith manual: intertidal invertebrates California Publications in Zoology. 23:1- from central California to Oregon. J. T. 470. Carlton (ed.). University of California 15. SCHWEITZER, C. E., and R. M. FELD- Press, Berkeley, CA. MANN. 2000. Re-evaluation of the Cancri- 6. LOUGH, R. G. 1975. Dynamics of crab dae Latreille, 1802 (Decapoda: Brachyura) larvae (Anomura: Brachyura) off the cen- including three new genera and three new tral Oregon coast, 1969-1971. Ph.D. Or- species. Contributions to Zoology. 69:223- egon State University, Corvallis, OR. 250. 7. MARTIN, J. W. 2014. Brachyura, p. 295- 16. SPAZIANI, E., K. DESANTIS, B. D. 310. In: Atlas of crustacean larvae. J. W. OROURKE, W. L. WANG, and J. D. Martin, J. Olesen, and J. T. Høeg (eds.). WELD. 1997. The clearance in vivo and Johns Hopkins University Press, Balti- metabolism of ecdysone and 3- more, MD. dehydroecdysone in tissues of the crab 8. PULS, A. L. 2001. Arthropoda: Decapo- Cancer antennarius. Journal of Experi- da, p. 179-250. In: Identification guide to mental Zoology. 279:609-619. larval marine invertebrates of the Pacific 17. WICKSTEN, M. K. 2011. Decapod crusta- Northwest. A. Shanks (ed.). Oregon cea of the Californian and Oregonian Zoo- State University Press, Corvallis, OR. geographic Provinces. http:// 9. RATHBUN, M. J. 1930. The Cancroid escholarship.org/uc/item/7sk9t2dz. crabs of America of the families Euryali- Scripps Institution of Oceanography, UC dae, Portunidae, Atelecyclidae, Cancri- San Diego, San Diego, CA. dae and Xanthidae. U.S. Government Updated 2015 Printing Office, Washington, D.C. T.C. Hiebert 10. RICKETTS, E. F., and J. CALVIN. 1971. Between Pacific tides. Stanford Universi- ty Press, Stanford, California. 11. ROESIJADI, G. 1976. Descriptions of the prezoeae of Cancer magister Dana and Cancer productus Randall and the larval stages of Cancer antennarius Stimpson (Decapoda: Brachyura). Crustaceana. 31:275-295.