Neotrypaea Californiensis Class: Multicrustacea, Malacostraca, Eumalacostraca
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Phylum: Arthropoda, Crustacea Neotrypaea californiensis Class: Multicrustacea, Malacostraca, Eumalacostraca Order: Eucarida, Decapoda, Pleocyemata, Axiidea The ghost shrimp Family: Callianassidae, Callianassinae Taxonomy: Neotrypaea californiensis was et al. 2007). described as a member of the genus Calli- Cephalothorax: anassa 1854 by Dana and remained there Eyes: Eyestalks flattened and with until an analysis by Manning and Felder acute tips. Pigmented corneas are mid-dorsal (1991) resulted in the three NE pacific Calli- within eyestalk (Fig. 2) (Wicksten 2011). anassa species moving to the new genus Eyes triangular and with diverging tip Neotrypaea. Tudge et al. (2000) later analy- (Campos et al. 2009). zed 93 characters of adult morphology and Antenna: Antennal angles rounded found the genus Neotrypaea to be non- and naked and antennal peduncle shorter monophyletic and Sakai (1999) than antennular peduncle (Campos et al. synonymized Neotrypaea and Callianassa. 2009). The monophyly of Neotrypaea is still Mouthparts: The mouth of decapod supported by some authors (e.g. Campos et crustaceans comprises six pairs of appendag- al. 2009) and we follow the most current es including one pair of mandibles (on either local intertidal guides, which use N. side of the mouth), two pairs of maxillae and californiensis (Kuris et al. 2007). For three pairs of maxillipeds. The maxillae and complete list of synonymies see Sakai maxillipeds attach posterior to the mouth and (2005). extend to cover the mandibles (Ruppert et al. 2004). The third maxilliped in N. californiensis Description is operculiform, with widened merus extend- Size: Males up to 115 mm and females to ing beyond articulation with carpus and ischi- 120 mm in length (Barnard et al. 1980; Puls um (Manning and Felder 1991; Campos et al. 2001; Wicksten 2011). 2009; Wicksten 2011). Color: Can be white to cream with patches Carapace: Smooth and with lateral of pinkish red or orange on the abdomen grooves (Wicksten 2011). and appendages (see Plate 19, Kozloff Rostrum: Not prominent, rounded and 1993; Wicksten 2011). The illustrated with small blunt tooth (Wicksten 2011) (Fig. specimen (from Coos Bay) is pale pink with 2). light orange abdomen. Teeth: General Morphology: The body of decapod Pereopods: Second pereopod flat- crustaceans can be divided into the cepha- tened, chelate (Fig. 3) and with row of setae lothorax (fused head and thorax) and abdo- along posterior margin (Campos et al. 2009). men. They have a large plate-like carapace Third to fifth pereopods are predominantly dorsally, beneath which are five pairs of tho- used in walking (MacGinitie 1934). Third racic appendages (see chelipeds and pere- pereopod with triangular carpus and round, opods) and three pairs of maxillipeds (see small dactyl. Fourth and fifth pereopods are mouthparts). The abdomen and associated slender (Wicksten 2011). appendages are outstretched and shrimp- Chelipeds: First chelipeds are chelate like in Callianassidae (Stevens 1928; Kuris 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. Neotrypaea californiensis. 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, Charles- ton, OR. and unequal (Fig. 1). The large cheliped is 1949). They burrow using their first to third broad, serrate and with an obvious gap in legs, aided by mouthparts (MacGinitie 1934; dactyls. The merus has a conspicuous ven- Kozloff 1993) and begin digging backward tral lobe, the carpus is almost square and before turning and removing excess loose longer than the palm, and with laterally in- sediment from the burrow to the surface (see curved dorsal margin (Campos et al. 2009). MacGinitie 1934 for figure). The dactyl has a recurved hook distally Possible Misidentifications (Wicksten 2011) (Fig. 1). Propodi are of Thalassinidea is a former infraorder nearly equal length (McGinitie 1934). containing Callianassidae and Upogebiidae Second chelipeds are both chelate with and, although shown to be non-monophyletic propodi and dactyls near equal in width (Sakai 2004), most mud and ghost shrimps (Figs. 1, 3). Female and immature are often referred to collectively as thalassi- individuals have hand longer than carpus nids. (Wicksten 2011). Upogebiidae is described in Williams Abdomen (Pleon): Abdomen elongate (1986) and Campos et al. 2009 and, locally, (longer than cephalothorax), not reflexed but consists of a single species, Upogebia extended, symmetrical and externally seg- pugettensis, the blue mud shrimp, often co- mented. It bears three pairs of fan-like pleo- occurs with N. californiensis. Upogebia pods (Fig. 1). First and second pleopods pugettensis is easy to recognize because it is are vestigal and absent in males. Third to larger and its color (bluish and never red or fifth are leaf-like (Fig. 1). In females, the first pink) is strikingly different. Its burrows are pleopods are uniramous and the second are also more firm and substantial. The most biramous (Wicksten 2011). noticeable morphological difference between Telson & Uropods: Telson nearly rectangu- the species is the first pair of legs: both of lar, forming a well-developed fan-shape with which are small, sub-chelate and equal in U. uropods, which are equal in length to the tel- pugettensis. Furthermore, its rostrum is hairy son (Fig. 1). Telson composed of two dorsal and has a laterally compressed and slender ribs and posterior marginal tooth. Exopod tip of the short fixed finger of the chela (outer ramus) also with dorsal ribs. (Wicksten 2011). Sexual Dimorphism: Pleopod (see Abdo- Characteristics defining the Callianas- men (Pleon)) and cheliped (see Chelipeds) sidae are described in Sakai 1999 and and morphology differs between males and fe- Campos et al. 2009. There are three species males. Females are also commonly seen locally, Neotrypaea californiensis, N. gigas with conspicuous bright orange egg masses and N. buffari (Kuris et al. 2007). Neotrypaea attached to their pleopods. californiensis can be distinguished from the Callianassidae-specific character other two species by the lack of a prominent Burrow: Neotrypaea californiensis build and rostrum (present in N. gigas) and eyestalks inhabit large, sloppy and permanent burrows that are acute and diverging tips of the with branching side tunnels (Y-shape, Jen- eyestalks (rather than short, blunt and not sen 1995; Puls 2001). Individuals dig tire- diverging in N. biffari) (see Campos et al. lessly, turning over acres of northwest oyster 2009). Neotrypaea gigas is larger (to 125– beds (Ricketts and Calvin 1971, see Behav- 150 mm) than the other two, and relatively ior). Burrows can be to 0.76–1.00 m deep rare in sandy sublittoral habitats. Its rostrum (MacGinitie 1934; MacGinitie and MacGinitie is sharp, with prominent medial tooth (whichN. 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] californiensis does not possess), and its first osmotic conformer, lower lethal limit 8.75– chela closes without a gap. It is more 10.5 (Thompson and Pritchard 1969b) and common in its southern distribution, south of the upper limit is 43.75 (Barnard et al. 1980). Point Conception (Barnard et al. 1980; Kuris Temperature: et al. 2007; Wicksten 2011). Neotrypaea Tidal Level: High intertidal. Collected at me- gigas and N. californiensis also differ in the dium high and upper to mid-intertidal zones morphology of the second pereopod: In N. (0.0–1.2 m, Ricketts and Calvin 1971). californiensis the propodus and dactyl are of Associates: The blue mud shrimp, Upogebia equal length and in N. gigas, the propodus is pugettensis, is found overlapping the range of curved and wider than the dactyl (Kuris et al. N. californiensis, though it is generally lower 2007). Recent examination of these two intertidally and in muddier sediments. species using morphological and molecular Common commensals in ghost shrimp data suggests that the key characters for burrows include a polynoid worm differentiating species is the length of Hesperonoe, pinnotherid crabs (Scleroplax eyestalks and shape of the distal outer glanulata), copepods (Hemicyclops, edges (Pernet et al. 2010). Clausidium), the shrimp Betaeus harrimani, the bopyrid isopod lone cornuta, the goby Ecological Information Clevelandia, the echiuroid worm Urechis Range: Type region is California, with pro- caupo, and the clam Cryptomya californica posed locality San Francisco or Monterey (MacGinitie 1934; Kuris et al. 2007; Campos Bay (Wicksten 2011), but type material has 2009; Wicksten 2011). been lost. Known range includes Alaska to Abundance: Common in Oregon's estuarine Tiajuana River, California and Point Abreo- mudflats. In Wallapa Bay, Washington, the jos, Baja California, Mexico (Campos et al. density of N. californiensis (up to 450 shrimp 2009). per m2) was always higher than that of the Local Distribution: Distribution in many Or- other locally occurring ghost shrimp, U. pu- egon estuaries including Coos Bay, Alsea gettensis (up to 100 shrimp per m2) Dumbauld River (Gaumer et al. 1973b), Nestucca es- et al. 1996). tuary (Gaumer et al. 1973a), Netarts Bay (Gaumer et al. 1974), Umpqua estuary Life-History Information (Umpqua Estuary 1978), Tillamook Bay Reproduction: Continuously reproductive in (Gaumer 1973b) and Yaquina Bay (Gaumer central California, especially June and July et al. 1974). (MacGinitie 1934; Ricketts and Calvin 1971). Habitat: Mud or sand. Individuals can sur- A breeding season in late spring and summer vive anoxia for nearly six days (Garth and is known to occur in Yaquina Bay, Oregon Abbott 1980). In adaptation to living in an (Puls 2001). Neotrypaea californiensis environment that is relatively low in oxygen, reach sexual maturity at 2 years and produce N.