Cancer Productus Class: Malacostraca Order: Decapoda, Reptantia Section: Brachyura the Red Rock Crab Family: Cancridae

Phylum: Arthropoda, Crustacea Cancer productus Class: Malacostraca Order: Decapoda, Reptantia Section: Brachyura The red rock crab Family: Cancridae

Taxonomy: Despite recent confusion Teeth: Ten antero-lateral teeth regarding a variety of cancrid genera, the (counting orbital tooth), nine large teeth that taxonomy of Cancer productus has remained become more acute posteriorly. stably within the genus Cancer (Harrison and Perepods: Dactyls thickly fringed Crespi 1999; Schweitzer and Feldmann 2000; above and below. Kuris et al. 2007; Wicksten 2012). Chelipeds: Dactyls dark-tipped and hands rough dorsally. Carpus wrinkled, with Description single tooth at inner angle (Queen 1930). Size: Carapace 97–174 mm in length and up Abdomen (Pleon): Abdomen narrow in to 157.5 mm in width (Schmitt 1921; Rathbun male, broad in female (e.g. see Cancer 1930). Females with carapace length up to magister, Fig. 3). 158 mm and males up to 200 mm (Puls Telson & Uropods: 2001). Sexual Dimorphism: Male and female Color: Dark red dorsally, lighter ventrally, brachyuran crabs are easily differentiable. legs mottled red and juveniles striped (Fig. 3). The most conspicuous feature, the abdomen, General Morphology: The body of decapod is narrow and triangular in males while it is crustaceans can be divided into the wide and flap-like in females. Additionally, cephalothorax (fused head and thorax) and males have one large chelae and two pleopod abdomen. They have a large plate-like pairs specialized for copulation however, the carapace dorsally, beneath which are five third and fourth pleopods are absent. pairs of thoracic appendages (see chelipeds Females, on the other hand, have all four and pereopods) and three pairs of pleopod pairs, each with long setae for egg maxillipeds (see mouthparts). The abdomen attachment (Brachyura, Kuris et al. 2007). and associated appendages are reduced and folded ventrally (Decapoda, Kuris et al. 2007). Possible Misidentifications Cephalothorax: According to some authors, the genus Cancer Eyes: Eyestalks short, orbits small. comprises 23 species (Harrison and Crespi Antennae: Antennules folded 1999 but see Schweitzer and Feldmann lengthwise, antennal flagella short and hairy 2000). This genus is differentiated from other (Queen 1930). brachyuran genera by the broadly oval Mouthparts: The mouth of decapod carapace, presence of five frontal teeth and crustaceans comprises six pairs of antennules that fold back over carapace. appendages including one pair of mandibles Characters unique to Cancer productus (on either side of the mouth), two pairs of include ten antero-lateral teeth, carapace maxillae and three pairs of maxillipeds. The widest at ninth tooth, bright red color and maxillae and maxillipeds attach posterior to black-tipped cheliped dactyls (Kuris et al. the mouth and extend to cover the mandibles 2007). (Ruppert et al. 2004). There are eight Cancer species known Carapace: Broadly oval, uneven and locally (Kuris et al. 2007). The most slightly convex. Widest at ninth antero-lateral morphologically similar to C. productus is C. tooth (Fig. 1) (Wicksten 2012). magister, which also has 10 antero-lateral Frontal Area: Markedly pronounced teeth and five subequal frontal teeth (Kuris et beyond eyes, with five nearly equal teeth (Fig. al. 2007). However, the carapace of C. 2). magister is widest at the tenth tooth, is more subtly pigmented and does not have black

A publication of the University of Oregon Libraries and the Oregon Institute of Marine Biology Individual species: http://hdl.handle.net/1794/12699 and full 3rd edition: http://hdl.handle.net/1794/18839 Email corrections to [email protected] tipped dactyls (Wicksten 2012). The two Abundance: Common (Carlton and Kuris species are often collected together in crab 1975). pots. Cancer antennarius, like C. productus, is dark red with spots ventrally and with black Life-History Information tipped chelae. However the carapace width Reproduction: In C. productus, mating in C. antennarius is widest at the eighth tooth occurs June–August (Puget Sound) (Knudsen and there are a total of 11 antero-lateral teeth 1964; Jaffe et al. 1987). When the female is (Wicksten 2012). Cancer oregonensis is a about to molt, male C. productus clasps the small, oval crab with 12–13 total teeth. The female and copulation takes place after remaining four species have nine antero- molting (i.e. female shell is soft). Fertilization lateral teeth (sometimes ten in older is internal and egg deposition occurs months specimens, Wicksten 2012). Cancer branneri later in December–January, at which point is a small species (35 mm) that is rare eggs are bright orange. All decapod intertidally and recognizable by cheliped crustacean females attach recently laid dactyls that are long, straight, black and gelatinous egg masses to their pleopods. spiny. Cancer gracilis is also small (27 mm) The outer embryo membrane thickens and a has white-tipped cheliped dactyls and C. strand develops that attaches each embryo to jordani (25 mm) has a hairy carapace and pleopod setae (Decapoda, Kuris et al. 2007). sharp curving teeth. Cancer anthonyi, the Eyespots and chromatophores are easily yellow rock crab, is larger than the previous visible in advanced embryos and make them three at 52 mm and has black-tipped cheliped appear gray when ready to hatch. Zoea dactyls (Kuris et al. 2007; Wicksten 2012). larvae hatch by early April (Knudsen 1964). A Populations of C. productus, C. anthonyi second brood is sometimes produced (Jaffe (southern California) and C. magister support et al. 1987). commercial fisheries (Kuris et al. 2007). Larva: The larvae of C. productus have been described (Trask 1970; Roesijadi 1976). Ecological Information Larval development proceeds via a prezoea Range: Kodiak, Alaska, to Magdalena Bay, (Roesijadi 1976) followed by a series of zoea Baja California (Schmitt 1921). (five total, telson with single lateral spine at Local Distribution: Occurs in a variety of each fork, Lough 1975) and megalopae local Oregon estuaries including Coos, stages, each marked by a molt. The zoea Yaquina, Umpqua, Coquille, Tillamook and megalopae of cancrid species are difficult (Gaumer et al 1973) on semi-protected rocky to distinguish. The larvae of C. productus, C. shores (Garth and Abbott 1980). oregonensis and C. magister are Habitat: Individuals appear to prefer gravel, morphologically similar (Puls 2001), but can rock, and hard bottom – C. productus does be differentiated (e.g. variation in setal not burrow and lacks straining apparatus for morphology, see Trask 1970). Cancer sand removal (Ricketts and Calvin 1971). productus zoea are planktotrophic and have Also found in rocky tidepools and among large compound eyes and four spines: one eelgrass (Ricketts and Calvin 1971; Garth each dorsal and rostral and two lateral (see and Abbott 1980). Adults tend to bury Fig. 1, Trask 1970; Martin 2014), which are themselves into soft sand as is seen in C. lacking in prezoeae (Roesijadi 1976). Larval magister, although less frequently (McGaw size (measured from tip of rostrum to tip of 2004). telson) proceeds from 2.5 mm (Zoea I and Salinity: Collected at 30. In San Francisco telson with pair of lateral exospines) to Bay salinity tolerance ranges from 21.7 to approximately 6 mm (Zoea V) (Trask 1970; 33.3 (Schmitt 1921). Puls 2001). The megalopae of C. productus Temperature: Collected at 11–17°C in the are about half the size of C. magister San Francisco Bay area (Schmitt 1921). megalopae (3.4–3.6 mm from rostrum to Tidal Level: Intertidal to about 79 m and posterior carapace and approximately 2 mm occurs closer to shore than C. magister (Puls at wides point) (Trask 1970). Larvae have 2001). been observed swarming in May (Friday Associates: Harbor, Jaffe et al. 1987). Hatching zoea to

Hiebert, T.C. 2015. Cancer productus. 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 megalopa stage requires 97 days in the Bibliography lab (Trask 1970). The megalopae of C. oregonensis and C. productus were described 1. BROCK, R. E., and L. D. SMITH. by DeBrosse et al. 1989 (see Fig. 1-2, 3-4, 1998. Recovery of claw size and DeBrosse et al. 1989). function following autotomy in Cancer Juvenile: Juveniles are often brightly colored productus (Decapoda: Brachyura). and possess several to many spots (see Biological Bulletin. 194:53-62. Krause-Nehring et al. 2010). Interestingly, 2. DEBROSSE, G. A., A. J. the wide variety of juvenile color morphs does BALDINGER, and P. A. not correspond to environmental background MCLAUGHLIN. 1990. A Comparative colors or food (Krause-Nehring et al. 2010). study of the megalopal stages of The carapace is widest at ninth tooth, naked Cancer oregonensis Dana and Cancer and often spotted or striped. Frontal and productus Randall (Decapoda: antero-lateral teeth are flat, rounded and fairly Brachyura: Cancridae) for the uniform (Fig. 3). northeastern Pacific. Fishery Bulletin. Longevity: 88:39-49. Growth Rate: Growth occurs in conjunction 3. GARTH, J. S., and D. P. ABBOTT. with molting. In pre-molting periods the 1980. Brachyura: The true crabs, p. epidermis separates from the old cuticle and 594-630. In: Intertidal invertebrates of a dramatic increase in epidermal cell growth California. R. H. Morris, D. P. Abbott, occurs. Post-molt individuals will have soft and E. C. Haderlie (eds.). Stanford shells until a thin membranous layer is University Press, Stanford, CA. deposited and the cuticle gradually 4. GAUMER, T., and E. AL. 1973. hardens. During a molt decapods have the Estuary resource use studies. Oregon ability to regenerate limbs that were Fish Commission, Portland, OR. previously autotomized (Kuris et al. 2007). 5. HARRISON, M. K., and B. J. CRESPI. Research has shown, however, that 1999. Phylogenetics of cancer crabs regenerated limbs handicap C. productus (Crustacea: Decapoda: Brachyura). foraging and predatory abilities (Brock and Molecular Phylogenetics and Smith 1998). Evolution. 12:186-199. Food: Cancer productus individuals are 6. KNUDSEN, J. W. 1964. Observations scavengers and predators on other of the reproductive cycles and ecology crustaceans, especially barnacles and other of the common Brachyura and crablike crabs (Knudsen 1964) as well as molluscs Anomura of Puget Sound, and polychaete worms. Zoea reportedly Washington. Pacific Science. 18:3-33. ingest Dendraster excentricus pluteus larvae, 7. KRAUSE-NEHRING, J., J. M. but their efficiency reduces with pluteus size STARCK, and A. R. PALMER. 2010. and age (Rumrill et al. 1985). Juvenile colour polymorphism in the Predators: Adults are commercially and red rock crab, Cancer productus: recreationally harvested for food. Additional patterns, causes, and possible predators include octopus, fish and birds adaptive significance. Zoology. (Knudsen 1964). Larval forms are predated 113:131-139. by filter and plankton feeders (herring, 8. KURIS, A. M., P. S. SADEGHIAN, J. salmon, and other fishes). T. CARLTON, and E. CAMPOS. 2007. Behavior: Individuals are dominant and stalk Decapoda, p. 632-656. In: The Light prey in tidepools at night (Ricketts and Calvin and Smith manual: intertidal 1971). They are also active in daylight and invertebrates from central California to individuals can aggregate by sex and age, Oregon. J. T. Carlton (ed.). University depending on egg-laying and molting cycles of California Press, Berkeley, CA. (Knudsen 1964). 9. LOUGH, R. G. 1975. Dynamics of crab larvae (Anomura: Brachyura) off the central Oregon coast, 1969-1971.

A publication of the University of Oregon Libraries and the Oregon Institute of Marine Biology Individual species: http://hdl.handle.net/1794/12699 and full 3rd edition: http://hdl.handle.net/1794/18839 Email corrections to [email protected] Ph.D. Oregon State University, 19. SCHWEITZER, C. E., and R. M. Corvallis, OR. FELDMANN. 2000. Re-evaluation of 10. MARTIN, J. W. 2014. Brachyura, p. the Cancridae Latreille, 1802 295-310. In: Atlas of crustacean (Decapoda: Brachyura) including three larvae. J. W. Martin, J. Olesen, and J. new genera and three new species. T. Høeg (eds.). Johns Hopkins Contributions to Zoology. 69:223-250. University Press, Baltimore, MD. 20. TRASK, T. 1970. A Description of 11. MCGAW, L. J. 2004. Ventilatory and laboratory reared larvae of Cancer cardiovascular modulation associated productus (Decapoda: Brachyura) and with burying behaviour in two a comparison to the larvae of Cancer sympatric crab species, Cancer magister. Crustaceana. 18:133-146. magister and Cancer productus. 21. WICKSTEN, M. K. 2011. Decapod Journal of Experimental Marine crustacea of the Californian and Biology and Ecology. 303:47-63. Oregonian Zoogeographic 12. PULS, A. L. 2001. Arthropoda: Provinces. http://escholarship.org/uc/it Decapoda, p. 179-250. In: em/7sk9t2dz. Scripps Institution of Identification guide to larval marine Oceanography, UC San Diego, San invertebrates of the Pacific Northwest. Diego, CA. A. Shanks (ed.). Oregon State University Press, Corvallis, OR. 13. QUEEN, J. C. 1930. Marine decapod crustacea of the Coos Bay, Oregon District. M.S. University of Oregon, Eugene, OR. 14. RATHBUN, M. J. 1930. The Cancroid crabs of America of the families Euryalidae, Portunidae, Atelecyclidae, Cancridae and Xanthidae. U.S. Government Printing Office, Washington, D.C. 15. RICKETTS, E. F., and J. CALVIN. 1971. Between Pacific tides. Stanford University Press, Stanford, California. 16. 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. 17. RUMRILL, S. S., J. L. PENNINGTON, and F. S. CHIA. 1985. Differential susceptibility of marine invertebrate larvae: laboratory predation of sand dollar, Dendraster excentricus (Eschscholtz) embryos and larvae by zoeae of the red crab, Cancer productus Randall. Journal of Experimental Biology. 90:193-208. 18. SCHMITT, W. L. 1921. The marine decapod crustacea of California. University of California Publications in Zoology. 23:1-470.