Phylum: Arthropoda, Crustacea hirsutiusculus Class: Order: Hairy Section: , Paguroidea Tribe: Paguridea

Taxonomy: The in the Paguroidea is elongated, soft and coiled in is complicated, especially among the genera (Kuris et al. 2007) (Fig. 1). Eupagurus, Bernhardus and Pagurus (described in McLaughlin et al. 2010). The Cephalothorax: International Commission of Zoological Eyes: Eyestalks short, stout and with Nomenclature (Opinion 472) placed the pointed ocular scales (Wicksten 2011). generic names Eupagurus and Bernhardus in Antennae: Antennal acicle usually the official index of invalid and rejected exceeds eyestalk in length. Chemoreceptors names, leaving the genera Pagurus on antennule hairs (Barnard et al. 1980). (Paguridae) and Dardanus (Diognidae) as Mouthparts: The mouth of decapod valid (Hemming 1958). Thus, previous comprises six pairs of synonyms for Pagurus hirsutiusculus include appendages including one pair of mandibles Bernhardus hirsutiusculus (McLaughlin et al. (on either side of the mouth), two pairs of 2010; Wicksten 2011). maxillae and three pairs of maxillipeds. The maxillae and maxillipeds attach posterior to Description the mouth and extend to cover the mandibles Size: Carapace length 19–32 mm (Barnard (Ruppert et al. 2004). et al. 1980; Kozloff 1993). Puget Sound to 50 Carapace: Shield (hard, anterior mm (Ricketts and Calvin 1971) and body portion) wider than long (McLaughlin 1972) often extends past the margin of the shell and (Fig. 1). cannot be retracted (Kuris et al. 2007). Rostrum: Triangular (Fig. 1), acute Color: Body color tan to black or green. and not much longer than lateral projections Antennae dark green with white stripes. of carapace (Wicksten 2011). Propodus of walking legs hairy and tipped Teeth: Sharp medial frontal tooth with white or pale blue and dactyls with (Barnard et al. 1980). vertical red stripes and blue spots at base. Pereopods: Two pairs of hairy Tips of chela tan or orange and walking legs walking legs with dactyls about as long as have white band on propodus and sometimes propodi, which are banded with white. a blue dot. Dactyls whitish and striped with Dactyls slender and about as long as propodi blue and red, antennal flagellum banded with (Wicksten 2011). Two pairs of small posterior translucent and brown (Wicksten 2011) or legs are adapted for holding shell. greenish with yellow spots (Barnard et al. Chelipeds: Left cheliped with small 1980). Most recognizable patterns are white hand and granular surface, slightly hairy and spots on antennae and white bands around wider than deep (Fig. 2). Right cheliped with base of second and third legs (see Plate 20 large hand, rounded, twice as wide as small and Fig 117, Kozloff 1993) (Fig. 1). hand, granular, slightly hairy and with one General Morphology: The body of decapod large tubercule on ventral surface (Fig. 2). crustaceans can be divided into the Cheliped stout and shorter than walking legs, cephalothorax (fused head and thorax) and is elongated and fingers gaping in male. abdomen. They have a large plate-like Merus and carpus with setae, granules, carapace dorsally, beneath which are five spines and ridges. pairs of thoracic appendages (see chelipeds Abdomen (Pleon): Abdomen asymmetrical, and pereopods) and three pairs of elongate, twisted, soft and not externally maxillipeds (see mouthparts). The abdomen segmented (Fig. 1). Bears small, unpaired pleopods.

Hiebert, T.C. 2015. Pagurus hirsutiusculus. In: Oregon Estuarine Invertebrates: Rudys' Illustrated Guide to Common , 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.

A publication of the University of Oregon Libraries and the Oregon Institute of Marine Biology Individual species: http://hdl.handle.net/1794/12728 and full 3rd edition: http://hdl.handle.net/1794/18839 Email corrections to [email protected] Telson & Uropods: Telson and uropods North America: Diogenidae, Parapaguridae small. Telson with slightly asymmetrical lobes and Paguridae (Wicksten 2011). and a shallow clefts laterally. Posterior Parapaguridae species occur on the margin with notch and spines. Uropods also continental shelf. Diogenidae species, called asymmetrical (Wicksten 2011). “left-handed” (left cheliped is equal to or Sexual Dimorphism: Males usually larger larger than right) hermit crabs, are generally than females (MacGinitie and MacGinitie subtidal and often inhabit the shells of moon 1949). snails. The Diogenidae includes three Shell: Usually inhabits Nassarius fossatus, local species, Isocheles pilosus, Paguristes lamellosa (e.g. this specimen) (in ulreyi, and P. bakeri). The Paguridae, or bays, Schmitt 1921), Nucella emarginata or “right-handed” (right cheliped is larger than Littorina sp. (Kozloff 1993). Individuals often left) hermit crabs, on the other hand, are a inhabit shells of Nucella spp. except in San speciose family locally, with 10 species, Francisco Bay, where it uses shells of inhabiting the intertidal zone to the continental gastropod species introduced from the shelf. Nine of the 10 local pagurid species Atlantic. Moves to larger shells with increased belong to the Pagurus (Kuris et al. growth. Innate selection of shell is dependent 2007). The hermit crabs of the genus on size, weight and shell volume (Reese Pagurus are hard to tell apart. However, 1962) and even the potential camouflaging many local species can be easily properties of the shell (Partridge 1980). differentiated by their bright red or orange Individuals carefully examine and select antennae and, likewise, many are similar to P. appropriate shells with their setaceous minor hirsutiuseulus in their lack of red antennae. chela. These setae have sensory structures Pagurus hirsutiusculus can be and chemoreceptors that contribute to shell distinguished from other Pagurus species in selection (Mesce 1993). Furthermore, shell that the carapace shield is conspicuously type (i.e. snail species) may be species- wider than long and has antennae that are specific and vary throughout ontogeny banded green and white. Furthermore, (Straughan and Gosselin 2014). Thus, individuals are often not able to fully retract available shells may be a limiting resource for into their shells. They are found inhabiting hermit crabs (Vance 1972; Worcester and the shells of Nucella spp. and may have Gaines 1997), but this may only be the case Crepidula spp. living on the inside or outside for a specific, preferred, shell type (i.e. of their shell. This species co-occurs with P. species). samuelis, but is the more common species in protected areas and bays. Possible Misidentifications Pagurus beringanus is also a low Hermit crabs (superfamilies, Coenobitoidea intertidal species, found at depths up to 364 and Paguroidea) are easily recognizable by m. This species has translucent antennae their unique morphology and the gastropod with a conspicuous lateral red mark and shells they inhabit (although they also inhabit usually inhabits shells of Nucella lamellosa, tubes, twigs or even bones). They use their Ceratostoma foliata and Fusitriton last preened pears to grip the shell and their oregonensis. It is found on rocky substrates soft abdomen with reduced pleopods and as well as sublittorally and has a whitish body, small telson and uropods. Their carapace is red banded walking legs, and has inverted V- usually rather thin, their eyes stalked and shaped tubercules on its hands (Wicksten have pigmented corneae. They have active 2011; Kuris et al. 2007). antennae, equipped with sensory setae. Pagurus quaylei is a subtidal species (to Their third maxillipeds are leg-like and bear 97 m) with antennae irregularly banded and setae and they have chelae that can be large dark brown, reddish brown eyestalks and enough to block their external shell aperture corneae with two bands. A common species or sexually dimorphic. amongst sand and polychaete tubes. , P. hemphilli, P. Three hermit-crab families are currently granosimanus, P. armatus, and P. caurinus recognized and occur on the west coast of all have red or orange antennae, where P.

Hiebert, T.C. 2015. Pagurus hirsutiusculus. 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. hirsutiuseulus does not. P. samuelis is a high Local Distribution: Coos Bay sites include intertidal species that is common and South Slough, near the channel at Collver abundant on the open coast, with red Point and the mudflat of Metcalf Preserve. antennae and carapace with white stripes. It Habitat: Protected areas with silt or in bays inhabits shells of Tegula spp and may have or harbors (Kozloff 1993; Wicksten 2011). Crepidula spp. living on top of or inside the Tidepools, under rocks (with coarse gravel), shell (Wicksten 2011). This species co- under seaweed (Kozloff 1993). South occurs with P. hirsutiusculus and is dominant Slough specimens occur within Zostera bed in to them in terms of shell competition and mudflats. Individuals appear to prefer algal exchange (Kuris et al. 2007). Pagurus cover (Orians and King 1964) and sandy hemphilli is a low intertidal and mostly subtidal tidepools (Reese 1962). Also present on the species (to 50 m) with red flagellum of rocky coast, in tide pools, bays and with antennae and corneae with distinct yellow coarse sand and gravel (Kuris et al. 2007). rings. This species usually inhabits the shells Salinity: Collected at 30, but tolerates of Tegula and Astraea spp, which are often brackish conditions (Barnard et al. 1980) themselves covered with red algae or small Temperature: mollusks (e.g. Crepidula adunca, Acmaea Tidal Level: Upper and middle intertidal mitra). Pagurus granosimanus is one of the zone to 110 m (McLaughlin 1972; Kuris et al. most common local hermit crab species in the 2007; Wicksten 2011). In South Slough at mid-littoral zone and within tide pools. This +0.15 m and -4.5 m. species has bright red antennae and Associates: In eelgrass, associates include commonly inhabits the shells of Tegula spp. Littorina spp. and amphipods (South Slough). is a low intertidal species, Associates includes those found within the found at depths up to 146 m, and usually shell and living with the hermit crab (e.g. inhabits the shells of Polinices spp., and are polynoid worms, Halosydna spp.) or sessile often covered with the pink hydroid organisms found on top of or within the shell Hydractinia sp. Pagurus caurinus is a (e.g. , and slipper shells, subtidal species, to 126 m, and while it has a Crepidula spp.) (Wicksten 2011). Polydorid northern distribution it is rare at that extent of worms can infect hermit crabs heavily its range. Pagurus ochetensis is a low (Polydora commensalis). The parasitic intertidal and subtidal species which often isopod, Pseudione giardi, is found with Puget inhabits moon snail shells (Kuris et al. 2007). Sound specimens (Barnard et al. 1980). Their chelipeds have a red stripe, and their Other parasites and their associates include corneae are yellowish green. the rhizocephalan parasite, Peltogaster puguri (22% females infected, 11.6% males, Alaska) Ecological Information as well as Peltogasterella gracilis and the Range: Type locality is Puget Sound, hyperparasite bopyrid isopod, Liriopsis Washington. Known range includes the pygmaea in southeastern Alaska (see Fig. 1, Pribilof Islands and Bering Strait to northern Warrenchuk and Shirley 2000). Japan (Barnard et al. 1980). Pacific Abundance: Usually abundant in tidepools Northwest to Monterey, California (Kozloff 1993) and is one of the common (McLaughlin 1972). Northern and southern hermit crabs (MacGinitie and MacGinitie populations used to be split into two 1949; Kuris et al. 2007). subspecies: P. hirsutiusculus hirsutiusculus (northern) and P. hirsutiusculus venturensis Life-History Information (Monterey Bay, California southward) Reproduction: Male deposits sperm near (Barnard et al. 1980). These subspecies the female abdomen after molting. The sperm were split into two formal species and, is stored and the female fertilizes eggs once currently, P. hirsutiusculus is replaced in its they are laid. Females are ovigerous from southern distribution by P. venturensis December through April (California, Barnard (Wicksten 2011). et al. 1980). Brooding begins in late fall and larvae hatch in February, with most females carrying several (~ five) broods a year

A publication of the University of Oregon Libraries and the Oregon Institute of Marine Biology Individual species: http://hdl.handle.net/1794/12728 and full 3rd edition: http://hdl.handle.net/1794/18839 Email corrections to [email protected] through spring and summer months. Each (Kozloff 1993). Some estuarine types filter brood contains up to 660 eggs and is plankton with their mouthparts (MacGinitie dependent on female size (Fitch and Lindgren and MacGinitie 1949). 1979). Predators: Other crabs. Larva: Larval development in P. Behavior: Lively and active, especially hirsutiuseulus has been described (Lough shallow water varieties (deepwater 1975; Fitch and Lindgren 1979) and proceeds are more sluggish, MacGinitie and MacGinitie via four zoea and, a final, megalopa stage, 1949) and will abandon shell in quiet waters each marked by a molt (Puls 2001). Pagurus (Ricketts and Calvin 1971). Based on a study hirsutiuseulus zoea are shrimp-like (see with Alaskan and southern Californian P. paguroid zoeae Fig. 53.2–3, Harvey et al. hirsutiusculus, it was suggested that 2014: Fig. 1, Fitch and Lindgren; Puls 2001), evolutionary shell loss may result from large, with telson posterior having seven 7 + 7 active species with northern populations spines, with the fifth spine longest and (Blackstone 1989). secondary setae on the inner uropod margin. Zoeal size at each stage proceeds as follows Bibliography: (13˚C, Fitch and Lindgren 1979; McLaughlin et al. 1988): 1.9–2.4 mm (Zoea I), 2.6–2.9 1. BARNARD, L. J., D. E. BOWERS, mm (Zoea II), 3.2–3.8 mm (Zoea III) and 4.1– AND E. C. HADERLIE. 1980. Macrura 5.2 mm (Zoea IV). The zoea of the Paguridae and Anomura, p. 577-593. In: Intertidal are morphologically similar and easiest to invertebrates of California. R. H. identify by the color and distribution of their Morris, D. P. Abbott, and E. C. chromatophores (visible only in live Haderlie (eds.). Stanford University specimens) (see Fig. 21, Puls 2001). The Press, Stanford, CA. megalopae have small and reduced telson 2. BLACKSTONE, N. W. 1989. Size, and uropods (as in adults), and chelipeds that shell-living and carcinization in are smooth, with no teeth or hairs (see Fig. geographic populations of a hermit 53.7 Harvey et al. 2014. Megalopae are 1.32 crab, Pagurus hirsutiusculus. Journal mm in length and 1.0 mm in width and are of Zoology. 217:477-490. often infested with bopyrid isopod Pseudione 3. BOLLAY, M. 1964. Distribution and giardi (Nyblade 1987; Puls 2001). Among use of gastropod shells by the hermit competent larvae, settlement can be delayed crabs Pagurus samuelis, Pagurus due to lack of shells or unavailability of food granosimanus, and Pagurus (Harvey and Colasurdo 1993; Worcester and hirsutiusculus at Pacific Grove Gaines 1997). California. Veliger, supplement 6:71- Juvenile: Antennae dark green with white 76. stripes and walking legs white-striped, but 4. FITCH, B. M., AND E. W. LINDGREN. never blue. Merus of both chelipeds is dark 1979. Larval development of Pagurus brown, other leg segments are light brown hirsutiusculus (Dana) reared in the (Bollay 1964). laboratory. Biological Bulletin. 156:76- Longevity: 92. Growth Rate: Growth occurs in conjunction 5. HARVEY, A. W., C. B. BOYKO, P. with molting. In pre-molting periods the MCLAUGHLIN, AND J. W. MARTINS. epidermis separates from the old cuticle and 2014. Anomura, p. 284-295. In: Atlas a dramatic increase in epidermal cell growth of larvae. J. W. Martin, J. occurs. Post-molt individuals will have soft Olesen, and J. T. Høeg (eds.). Johns shells until a thin membranous layer is Hopkins University Press, Baltimore. deposited and the cuticle gradually 6. HARVEY, A. W., AND E. A. hardens. During a molt decapods have the COLASURDO. 1993. Effects of shell ability to regenerate limbs that were and food availability on previously autotomized (Kuris et al. 2007). metamorphosis in the hermit crabs Food: A detritivore, eats detritus and Pagurus hirsutiusculus (Dana) and scavenges for dead plant and material Pagurus granosimanus (Stimpson).

Hiebert, T.C. 2015. Pagurus hirsutiusculus. 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. Journal of Experimental Marine Paguroidea. Raffles Bulletin of Biology and Ecology. 165:237-249. Zoology: 5-107. 7. HEMMING, F. 1958. Official index of 15. MESCE, K. A. 1993. Morphological rejected and invalid family-group and physiological identification of names in zoology. First installment: chelar sensory structures in the hermit names 1-273. International Trust for crab Pagurus hirsutiusculus Zoological Nomenclature, London. (Decapoda). Journal of Crustacean 8. KOZLOFF, E. N. 1993. Seashore life Biology. 13:95-110. of the northern Pacific coast: an 16. NYBLADE, C. F. 1987. Phylum or illustrated guide to Northern California, Subphylum Crustacea, Class Oregon, Washington, and British Malacostraca, Order Decapoda, Columbia. University of Washington Anomura, p. 441-450. In: Press, Seattle, WA. Reproduction and Development of 9. KURIS, A. M., P. S. SADEGHIAN, J. Marine invertebrates of the northern T. CARLTON, AND E. CAMPOS. Pacific coast. M. F. Strathmann (ed.). 2007. Decapoda, p. 632-656. In: The University of Washington Press, Light and Smith manual: intertidal Seattle, WA. invertebrates from central California to 17. ORIANS, G. H., AND C. E. KING. Oregon. J. T. Carlton (ed.). University 1964. Shell selection and invasion of California Press, Berkeley, CA. rates of some Pacific hermit crabs. 10. LOUGH, R. G. 1975. Dynamics of Pacific Science. 18:297-306. crab larvae (Anomura: Brachyura) off 18. PARTRIDGE, B. L. 1980. Background the central Oregon coast, 1969-1971. camouflage: an additional parameter Ph.D. Oregon State University, in hermit crab shell selection and Corvallis, OR. subsequent behavior. Bulletin of 11. MACGINITIE, G. E., AND N. Marine Science. 30:914-916. MACGINITIE. 1949. Natural history of 19. PULS, A. L. 2001. Arthropoda: marine animals. McGraw-Hill Book Decapoda, p. 179-250. In: Co., New York. Identification guide to larval marine 12. MCLAUGHLIN, P. A. 1972. The invertebrates of the Pacific Northwest. Hermit Crabs of the genus Pagurus A. Shanks (ed.). Oregon State (Crustacea, Decapoda, Paguridae) University Press, Corvallis, OR. from northwestern North America, with 20. REESE, E. S. 1962. Shell selection a partial revision of the genus. Ph.D. behavior of hermit crabs. Animal George Washington University. Behavior. 10:347-360. 13. MCLAUGHLIN, P. A., R. H. GORE, 21. RICKETTS, E. F., AND J. CALVIN. AND J. A. CRAIN. 1988. Studies on 1971. Between Pacific tides. Stanford the provenzanoi and other pagurid University Press, Stanford, California. groups: II. A reexamination of the 22. RUPPERT, E. E., R. S. FOX, AND R. larval stages of Pagurus hirsutiusculus D. BARNES. 2004. Invertebrate hirsutiusculus (Dana) (Decapoda, zoology: a functional evolutionary Anomura, Paguridae) reared in the approach. Thomson Brooks/Cole, laboratory. Journal of Crustacean Belmont, CA. Biology. 8:430-450. 23. SCHMITT, W. L. 1921. The marine 14. MCLAUGHLIN, P. A., T. KOMAI, R. decapod crustacea of California. LEMAITRE, AND D. L. RAHAYU. University of California Publications in 2010. Annotated checklist of Zoology. 23:1-470. anomuran decapod crustaceans of the 24. STRAUGHAN, N. A., AND L. A. world (exclusive of the Kiwaoidea and GOSSELIN. 2014. Ontogenetic families Chirostylidae and Galatheidae changes in shell preferences and of the Galatheoidea) Part I: resource partitioning by the hermit Lithododiea, Lomisoidea and crabs Pagurus hirsutiusculus and P. granosimanus. Journal of

A publication of the University of Oregon Libraries and the Oregon Institute of Marine Biology Individual species: http://hdl.handle.net/1794/12728 and full 3rd edition: http://hdl.handle.net/1794/18839 Email corrections to [email protected] Experimental Marine Biology and Ecology. 451:1-8. 25. VANCE, R. R. 1972. Competition and mechanism of coexistence in three sympatric species of intertidal hermit crabs. Ecology. 53:1062-1074. 26. WARRENCHUK, J. J., AND T. C. SHIRLEY. 2000. Parasitism by the rhizocephalan Peltogaster paguri (Rathke, 1842) and hyperparasitism by the bopyrid isopod Liriopsis pygmaea (Rathke, 1843) on Pagurus hirsutiusculus (Dana, 1851) in southeastern Alaska. Crustaceana. 73:971-977. 27. WICKSTEN, M. K. 2011. Decapod crustacea of the Californian and Oregonian Zoogeographic Provinces. http://escholarship.org/uc/it em/7sk9t2dz. Scripps Institution of Oceanography, UC San Diego, San Diego, CA. 28. WORCESTER, S. E., AND S. D. GAINES. 1997. Quantifying hermit crab recruitment rates and megalopal shell selection on wave-swept shores. Marine Ecology Progress Series. 157:307-310.

Hiebert, T.C. 2015. Pagurus hirsutiusculus. 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.