Crustacean Biology

Rediscovery of the horseshoe shrimp Lightiella serendipita Jones, 1961 (Cephalocarida: Hutchinsoniellidae) in San Francisco Bay, California, USA, with a key to the worldwide species of Cephalocarida

Type Article

Author Garcia, Crystal; Woo, Isa; Rogers, D. Christopher; Flanagan, Alison M.; De La Cruz, Susan E. W.

Title Rediscovery of the horseshoe shrimp Lightiella serendipita Jones, 1961 (Cephalocarida: Hutchinsoniellidae) in San Francisco Bay, California, USA, with a key to the worldwide species of Cephalocarida

Journal title Journal of Crustacean Biology

URI http://hdl.handle.net/20.500.12634/629

Rights This work is written by (a) US Government employee(s) and is in the public domain in the US.

Download date 30/09/2021 08:05:15 applyparastyle "fig//caption/p[1]" parastyle "FigCapt" applyparastyle "fig" parastyle "Figure" Journal of Crustacean Biology Journal of Crustacean Biology The Crustacean Society Journal of Crustacean Biology (2020) 1–7. doi:10.1093/jcbiol/ruaa044 Downloaded from https://academic.oup.com/jcb/article-abstract/doi/10.1093/jcbiol/ruaa044/5874902 by Zoological Society of San Diego user on 04 August 2020

Rediscovery of the horseshoe shrimp Lightiella serendipita Jones, 1961 (Cephalocarida: Hutchinsoniellidae) in San Francisco Bay, California, USA, with a key to the worldwide species of Cephalocarida

Crystal Garcia1,2, , Isa Woo1, , D. Christopher Rogers3, , Alison M. Flanagan1,4, and Susan E.W. De La Cruz1, 1U.S. Geological Survey, Western Ecological Research Center, San Francisco Bay Estuary Field Station, PO Box 158, Moffett Field, CA 94035-0158, USA; 2Current affiliation: ICF International Inc., 2600 Hilltop Dr. Suite C137, Richmond, CA 94086, USA; 3Kansas Biological Survey and Biodiversity Institute, University of Kansas, Higuchi Hall, 2101 Constant Avenue, Lawrence, KS 66047-3759, USA; and 4Current affiliation: Department of Recovery Ecology, Institute for Conservation Research, San Diego Zoo Global, Escondido, CA 92027, USA

Correspondence: S.E.W. De La Cruz; e-mail: [email protected] (Received 10 April 2020; accepted 25 June 2020)

ABSTRACT Lightiella serendipita Jones, 1961 was first discovered in San Francisco Bay, California in 1953, but it had not been observed since 1988. In 2017, a total of 13 adult L. serendipita specimens were found as part of a study in central San Francisco Bay, nearly doubling the total number of specimens ever collected. We measured vertical distribution of macroinvertebrates and environmental variables, including grain size and chemical composition of sediment samples, to evaluate potential features associated with the habitat of the species. Specimens were generally found in sediments with low organic matter (1.7–3%), high sulfate concentrations

(594.6–647 ppm SO4), fine grain size (12.8–36.2% sand, 35.6–58% silt, 22.8–37.6% clay) and were mostly found in deep core sections (4–10 cm). Specimens were also consistently observed in cores containing tube-forming Polychaeta (i.e., Sabaco elongatus (Verrill, 1873) and Capitellidae), suggesting L. serendipita may have a commensal relationship with sedentary polychaetes, as do other cephalocaridans such as Lightiella incisa Gooding, 1963. We provide a scanning electron micrograph of L. serendipita and the first complete key to the species in class Cephalocarida to help elucidate the taxonomy of this rare crustacean taxon. The per- ceived absence of L. serendipita in previous surveys of the Bay may be attributable to its rarity; however, additional research is needed to fully understand habitat requirements and popula- tion size of this unique endemic species. Key Words: benthic invertebrates, endemic species, subtidal habitats

INTRODUCTION poorly understood (Sanders & Hessler, 1964; McLaughlin, 1976; Saloman, 1978; De Troch et al., 2000; Carcupino et al., 2006; Cephalocaridans (class Cephalocrida), commonly referred to as Addis, 2008). horseshoe shrimps, is a poorly understood group of marine crust- Adult cephalocaridans measure ~ 4 mm in length. The adult aceans, with only 13 species recognized worldwide, all of which body posterior to the cephalon consists of nine limb-bearing are reported as uncommon to rare (Olesen et al., 2011). Only thoracic segments (thoracic limb VIII is absent in Lightiella Jones, three species have been collected from more than one locality 1961), 10 limbless abdominal segments, and a telson (Olesen et al., (Carcupino et al., 2006; Olesen et al., 2011); the rest are considered 2014). No eyes have been observed in either the adult or larval endemic. Due to their rarity, small size, and wholly benthic life stages (Olesen et al., 2011). stages, cephalocaridans remain substantially understudied. Since Cephalocaridans are simultaneous hermaphrodites with prob- cephalocaridans have been observed across wide temperature able self-fertilization (Hessler et al., 1970, 1995). Their immo- ranges, in substrates with and without seagrasses, and in inter- bile sperm suggests that individuals must be in direct contact to tidal as well as deep-sea habitats, their habitat requirements are

Published by Oxford University Press on behalf of The Crustacean Society 2020. This work is written by (a) US Government employee(s) and is in the public domain in the US. C. GARCIA ET AL. cross-fertilize (Addis, 2008). Larval development shows a pro- METHODS nounced anamorphic gradual growth characterized by a high number of postembryonic stages (metanauplius and juvenile) Sampling and collection (Olesen et al., 2014). Lightiella serendipita was found in benthic cores that were collected Lightiella (family Hutchinsoniellidae Sanders, 1955) is the lar- as part of a multi-year (USGS, Western Ecological Research gest genus of Cephalocrida, with five described species. Lightiella Center (WERC)) study that evaluated the potential impacts of Downloaded from https://academic.oup.com/jcb/article-abstract/doi/10.1093/jcbiol/ruaa044/5874902 by Zoological Society of San Diego user on 04 August 2020 serendipita (Fig. 1) is the type species for the genus by designation. It maintenance dredging on demersal-fish foraging habitats (De La is the only known cephalocaridan from the eastern North Pacific Cruz et al., 2017). Study sites in six marinas (Table 2) were sam- and is one of two species from the Pacific coast of the Americas. pled as part of this effort. All sites were located on the western Other species of the genus are recorded from the American side of central SFB, a predominately polyhaline zone (Thompson Atlantic and Caribbean Sea, the Mediterranean, and New et al., 2007, 2013), and were relatively shallow (≤ 3.2 m mean Caledonia (Olesen et al., 2011). lower low water) with muddy (silt-clay) sediments. Lightiella serendipita was first documented by Jones & Hand Each study site contained three to seven transects (each ap- (1956) and later described by Jones (1961), who collected seven proximately 120 m in length) placed in a recently dredged area specimens during four sampling events from 1953 to 1957 in as well as an adjacent undredged reference area. A minimum of San Francisco Bay (SFB), California, USA (Fig. 2). The seven six coring locations were placed 20 m apart from each other on specimens included two juveniles, three adults, and two in- each of the transects. Two replicate cylindrical cores (10 cm × dividuals of unknown life stages. Reish et al. (1975) collected 10 cm) were collected at each coring location. A total of 1,362 an unidentified cephalocaridan from Anaheim Bay, southern samples were collected during three sampling periods (August California, which may either represent a range extension of 2016, January 2017, and August 2017; Table 2). In August 2016, L. serendipita or a new species. Nine confirmed adult specimens cores were separated into 2 cm sections from Mooring Road and of L. serendipita were collected three decades after its description Pier 32 sites to evaluate how invertebrate abundance and biomass by Jones (1961) in Berkeley, Coyote Point, and San Leandro, changed with sediment depth. Thereafter, samples were divided California by the U.S. Geological Survey (USGS) San Francisco into two sections (0 to 4 cm and 4 to 10 cm) because preliminary Bay Regional Effects Monitoring Program (Table 1, Fig. 2; analyses indicated that most of the abundance and biomass was in Schemel et al., 1988; 1990). the upper 4 cm of the cores (De La Cruz et al., 2017). One sedi- San Francisco Bay is the largest estuary on the west coast of ment core was collected at each transect to characterize sediment the Americas and contains approximately 90% of the coastal grain size (percent sand, silt, and clay) and chemical composition wetlands remaining in California (Goals Project, 2015). The es- (nitrate, sulfur, organic matter, and sedimentary pH). Sediment tuary is one of the most important ecosystems for sustaining en- samples were processed by A & L Agricultural Laboratories demic or endangered species in California, including several (Modesto, CA, USA). anadromous fishes (Swanson, 2007; California State Coastal Faunal cores were rinsed through a 0.5 mm sieve, and ani- Conservancy, 2010) and the commercially important Dungeness mals retained by the sieve were preserved in a 70% ethanol, 1% crab (Metacarcinus magister (Dana, 1852) (Taso, 1979; California rose bengal solution. All macroinvertebrates were sorted, identi- State Coastal Conservancy, 2010). It also supports almost 500 spe- fied, and enumerated by the USGS San Francisco Bay Estuary cies of invertebrates (Goals Project, 1999). While there are many Invertebrate Ecology Laboratory (SFBE IEL), Fremont, CA, USA. active restoration projects throughout the SFB region, habitat loss Identifications followed Light & Carlton (2007) and the taxonomic and degradation as well as the introduction of non-native spe- key provided by Jones (1961). cies remain constant threats (Takekawa et al., 2006; San Francisco All data from the samples containing L. serendipita were summar- Estuary Partnership, 2015, 2016). SFB is the most invaded aquatic ized for descriptive purposes only since the small number of in- ecosystem in North America (Cohen & Carlton, 1995; Zeug dividuals detected precluded the possibility of statistical analyses. et al., 2014; Jimenez & Ruiz, 2016), making the rediscovery of Morphological observations and information in the literature were L. serendipita even more remarkable. used to create the first key to the worldwide genera and species of We present the first new records of L. serendipita from SFB in Cephalocarida. nearly 30 years, plus associated ecological data, which were col- All material examined is deposited in the collections of U.S. lected as part of a large USGS study. Geological Survey, Western Ecological Research Center, San Francisco Bay Estuary Field Station, with the exception of two specimens in the collections of D. Christopher Rogers, University of Kansas.

RESULTS We found 13 L. serendipita adults (Table 1) in nine out of a total of 1,362 benthic cores, representing a very low detection rate of 0.66%. Four individuals were found in sediment depths of 0–4 cm, one in 4–6 cm, and eight in 6–10 cm. All individuals collected were adults and measured ~ 4 mm in length. We did not detect any larvae, which was probably an artifact of the 0.5 mm sieve size used to process all samples. The sediment properties of sites containing L. serendipita included low organic matter (1.7–3%), high sulfate concentrations (594.6–1647 ppm), and fine-grained sediments (12.8–36.2% sand, 35.6–58% silt, 22.8–37.6% clay). All L. serendipita individuals we encountered were found with polychaetes (Sabaco elongatus Kinberg, 1866 and Capitellidae) that form well-developed tube systems. No other taxa were consistently Figure 1. Lightiella serendipita Jones, 1961. Scale bar = 0.1 mm. found among the samples (Supplementary material Table S1).

2 REDISCOVERY OF LIGHTIELLA SERENDIPITA Downloaded from https://academic.oup.com/jcb/article-abstract/doi/10.1093/jcbiol/ruaa044/5874902 by Zoological Society of San Diego user on 04 August 2020

Figure 2. Locations of collections of Lightiella serendipita reported herein (USGS WERC, 2016–2017), the USGS SFB Regional Effects Monitoring Program (SFB REMP, 1987–1988), and M.L. Jones (1953–1957; Jones, 1961). This figure is available in color at Journal of Crustacean Biology online.

Lightiella serendipita were also primarily observed in cores from sam- Moreover, all individuals of L. serendipita were found in associ- pling locations that were not dredged, with the exception of three ation with tube-forming, sedentary polychaetes, suggesting a po- specimens collected in a single core from an area dredged four tential commensal relationship similar to that described between years prior to its collection (Table 1). These three specimens were certain polychaetes and L. incisa by De Troch et al. (2000). Tubes collected 20 m from a reference area. of burrowing macrofauna can create oxygenated microhabitats in otherwise anoxic sediment layers (Meyers et al., 1987, 1988), re- sulting in higher bacterial activity and meiofaunal densities (Aller DISCUSSION & Aller, 1986; Thomsen & Altenbach, 1993). Although De Troch et al. (2000) found that the majority of meiofauna did not co-occur We present the first reported collections of L. serendipita in nearly with polychaetes in deeper sediment depths, L. incisa (2.0–2.6 mm 30 yr. The species was detected in < 1% of the samples collected, length) apparently followed polychaetes into deeper sediment suggesting that, like other cephalocaridan species, it is remark- layers. Since tube-dwelling polychaetes can provide habitat struc- ably rare. Our study provides some of the first information on the ture and stability in addition to higher oxygen concentrations, it habitat of L. serendipita, including sediment characteristics and po- is possible that a possible commensal relationship between tube- tential community associations. dwelling polychaetes and L. serendipita may enable L. serendipita to As in other species of Lightiella, the majority of L. serendipita spe- occur in anoxic sediments. cimens occurred in fine-grained (Gooding, 1963; Sanders, 1963; The USGS Regional Effects Monitoring Program (REMP) Sanders & Hessler, 1964; McLaughlin, 1976; Saloman, 1978; for San Francisco Bay collected samples of benthic invertebrate Carcupino et al., 2006, Addis, 2008) and sulfide-rich sediments from 1987 through 1991 and found a total of nine specimens of (Felder & Camp, 2009), and were present in nearly anoxic condi- L. serendipita (Schemel et al.,1988, 1990) in SFB at depths similar to tions (De Troch et al., 2000). The species was found predominantly those sampled in our study (~ 10 cm). Seven of these specimens in undredged areas and in 6–10 cm sediment depths. were collected near Berkeley, one from north of Coyote Point, and

3 C. GARCIA ET AL.

Table 1. The number of Lightiella serendipita found in previous efforts and in the present study, associated collection period and sampling dates, site names (localities) in SFB (San Francisco Bay), dredge status (reference, dredged or not applicable (NA)), sediment depths (depth in cm or not applicable (NA)), co- ordinates, and data source.

No. of L. serendipita Collection period SFB site Reference or Sediment depth (cm) Latitude Longitude Source dredged Downloaded from https://academic.oup.com/jcb/article-abstract/doi/10.1093/jcbiol/ruaa044/5874902 by Zoological Society of San Diego user on 04 August 2020

1 12 March 1987 Berkeley NA NA 37.87383 −122.353 Schemel et al. 1988 1 8 March 1988 Berkeley NA NA 37.87380 −122.353 Schemel et al. 1990 (published herein) 1 8 March 1988 Coyote Point NA NA 37.66583 −122.201 Schemel et al. 1990 (published herein) 3 31 May 1988 Berkeley NA NA 37.87383 −122.353 Schemel et al. 1990 (published herein) 1 31 May 1988 San Leandro NA NA 37.60500 −122.311 Schemel et al. 1990 (published herein) 1 28 July 1988 Berkeley NA NA 37.87383 −122.353 Schemel et al. 1990 (published herein) 1 1 Nov 1988 Berkeley NA NA 37.87383 −122.353 Schemel et al. 1990 (published herein) 1 25 August 2016 Paradise Cay Reference 6–8 37.90967 −122.472 USGS WERC, Current study 2 25 August 2016 Paradise Cay Reference 8–10 37.90967 −122.472 USGS WERC, Current study 1 31 August 2016 Richardson Bay Reference 0–2 37.87574 −122.502 USGS WERC, Current study 1 31 August 2016 Richardson Bay Reference 8–10 37.87776 −122.503 USGS WERC, Current study 1 31 August 2016 Richardson Bay Reference 4–6 37.87730 −122.503 USGS WERC, Current study 1 6 Sept 2016 Yacht Harbor Reference 6–8 37.91522 −122.473 USGS WERC, Current study 1 4 January 2017 Richardson Bay Reference 8–10 37.87742 −122.503 USGS WERC, Current study 1 4 January 2017 Richardson Bay Reference 6–8 37.87742 −122.503 USGS WERC, Current study 1 8 August 2017 Paradise Cay Reference 4–10 37.90964 −122.473 USGS WERC, Current study 3 15 August 2017 Richardson Bay Dredged 0–4 37.87708 −122.504 USGS WERC, Current study

Table 2. Summary of the six study sites in San Francisco Bay, California that were included in the USGS WERC 2016 and 2017 sampling. All sites were sampled in August. Salinity regimes taken from Thompson et al. (2013).

Study area Location Salinity regime Habitat type Sediment texture Dredge depth MLLW (m) Last dredged Estimated dredging frequency (years)

Mooring Road San Rafael Poly/mesohaline Marina silt, clay 1. 8 2013 infrequent Richardson Bay Sausalito Polyhaline Marina silt, clay 3.2 2013 3 Paradise Cay Tiburon Polyhaline Channel silt, clay 2.4 2014 4 Strawberry Channel Mill Valley Polyhaline Channel silt, clay 2.1 2014 7 Loch Lomond San Rafael Poly/mesohaline Marina silt, clay 2.7 2015 12 Yacht Harbor Paradise Cay Polyhaline Marina silt 3 2015 4

one between San Leandro and Hayward (Table 1, Fig. 2). There August 2017), one of which was during an abnormally wet were two additional attempts to locate the species in SFB since winter (January 2017; Swain et al., 2018). It is unclear, how- this early REMP effort, both of which were unsuccessful. The first ever, whether seasonal pulses of precipitation and freshwater attempt included sampling near Mare Island, Vallejo and at the runoff would have altered bottom-water salinity to the extent mouth of the Petaluma River, CA from 1997 to 1999, using an that it would impact the distribution and/or abundance of this Ekman grab sampler (15.24 cm length, 15.24 cm width, 15.24 cm polyhaline species. Additional samples collected throughout the height; Wildco®, Yulee, FL, USA) (DCR, unpublished data). The year would be required to assess seasonal trends in the abun- second took place between 2000 and 2004, when benthic samples dance of the species. were collected using a modified Peterson grab (Mooi et al. 2007) at While L. serendipita was detected in < 1% of our samples, localities close to previous L. serendipita collections: Berkeley pier, the 13 collected specimens nearly doubled the total number of Point Richmond, and South San Francisco. specimens collected since the species was first documented by All specimens of L. serendipita collected were adults; however, Jones & Hand (1956). The relatively high number of specimens this may have been related to the sieving mesh size we used. Adult collected, coupled with the other ecological data obtained at cephalocaridans are classified as macrofauna, their larvae as meio- each sampling location, enabled us to establish a better under- fauna based on the definitions by Giere (2008). Our 0.5 mm sieve standing of the potential habitat characteristics of this rare retained adult L. serendipita and should also have retained juveniles, cephalocaridan. Additional research should focus on obtaining yet we did not detect any in our samples. We also did not detect larval or juvenile specimens that would facilitate further insight any larvae, which would require a finer mesh size of 0.02 mm. into the life history and morphology of the species, as well as We detected L. serendipita during all three sampling periods investigating habitat requirements of this rare and enigmatic in this study, two of which were in summer (August 2016 and crustacean.

4 REDISCOVERY OF LIGHTIELLA SERENDIPITA

Key to genera of Cephalocarida

1. Penultimate thoracic segment and telson each with a ventral setal comb; thoracopod VIII present �� 2 1′ Penultimate thoracic segment without ventral setal comb; telson bearing a ventral setal comb; thoracopod VIII absent Lightiella

2(1) Abdominal pleura with free portion width ≥ 0.3× corresponding abdominal segment length; antenna II, antennomere II some- Downloaded from https://academic.oup.com/jcb/article-abstract/doi/10.1093/jcbiol/ruaa044/5874902 by Zoological Society of San Diego user on 04 August 2020 times bearing a glabrous knob �� 3 2′ Abdominal pleura with free portion width < 0.25× corresponding abdominal segment length; antenna II, antennomere II bearing a hirsute knob �� Hutchisoniella macracantha Sanders, 1955 (Atlantic coast of the Americas) 3(2) Cephalon with ventromarginal hooks �� 4 3′ Cephalon without ventromarginal hooks �� Chiltoniella elongata Knox & Fenwick, 1977 (Hawke Bay, New Zealand) 4(3) Thoracopod VII exopod articles serially homologous, becoming smaller distally �� Sandersiella 4′ Thoracopod VII exopod articles not serially homologous; article III with a large lateral, digitiform projection; article IV with a rounded lateral projection bearing numerous setae �� Hampsonellus brasiliensis Hessler & Wakabara, 2000 (Brazil)

Key to species of Lightiella (adapted from McLaughlin, 1976)

1 Telson with pair of dorsal terminal spines �� 2 1′ Telson without dorsal terminal spines … Lightiella serendipita Jones, 1961 (San Francisco Bay and Anaheim Bay?, California, USA) 2(1) Thoracic segment VIII without pleura �� 3 2′ Thoracic segment VIII with pleura �� 4 3(2) Thoracopod VI endopod with two claws �� Lightiella incisa Gooding, 1963 (Caribbean Sea and Mobile Bay, Alabama, USA) 3′ Thoracopod VI endopod with one claw �� Lightiella magdalenina Carcupino, Floris, Addis, Castelli, Aurini-Galletti, 2006 (Sardinia, Italy) 4(2) Caudal rami length ~0.5× combined length of last two abdominal segments �� Lightiella monniotae Cals & Deboutteville, 1970 (St. Vincent Bay, New Caledonia) 4′ Caudal rami length approximately equal to combined length of last two abdominal segments �� Lightiella floridana McLaughin, 1976 (Florida, USA)

Key to species of Sandersiella

1 Abdomen distal half with pleura width > length �� 2 1′ Abdomen distal half with pleura width subequal to length �� ... Sandersiella chilenica Stuardo & Vega, 2011 (Coliumo Bay, Chile) 2(1) Thoracic segment VII in dorsal view serially homologous with preceding free thoracic segments �� 3 2′ Thoracic segment VII in dorsal view with pleura directed posterolaterally away from segment VI pleura about 70°; abdominal pleura posteriorly acuminate �� Sandersiella acuminata Shiino, 1965 (Ariake Bay, Japan) 3(2) Cephalon with ventro-marginal hooks �� 4 3′ Cepahalon without ventro-marginal hooks �� Sandersiella bathyalis Hessler & Sanders, 1973 (Walvis Bay, Namibia) 4(3) Cephalon with 5–9 ventro-marginal hooks �� Sandersiella calmani Hessler & Sanders, 1973 (Pacific Ocean off Peru) 4′ Cephalon with 11–12 ventromarginal hooks �� Sandersiella kikuchii Shimomura & Akiyama, 2008 (Kamogawa Canyon, off Boso Peninsula, Japan)

SUPPLEMENTARY MATERIAL with synthesis support from USGS Ecosystems Mission Area. Samples were collected under California Department of Fish and Supplementary material is available at Journal of Crustacean Biology online. S1 Table. Collection data for invertebrate taxa present in sam- Wildlife Permit SC-801158-03. Any use of trade, firm, or product ples containing specimens of Lightiella serendipita. names is for descriptive purposes only and does not imply endorse- ment by the U.S. Government. Special thanks to Brenda Goeden (San Francisco Bay Conservation and Development Commission), ACKNOWLEDGMENTS Korie Schaffer (NOAA), and the landowners and managers Data collection were funded by the San Francisco Estuary Institute of our study sites (Mooring Road Neighborhood Association, Regional Monitoring Program and U.S. Army Corps of Engineers, Richardson Bay Marina Harbor Master, Paradise Cay Home

5 C. GARCIA ET AL.

Owners Association, Strawberry Channel Recreation District, Jimenez, H. & Ruiz, G.M. 2016. Contribution of non-native species to Marina Village Associates LLC, Paradise Cay Yacht Harbor) for soft-sediment marine community structure of San Francisco Bay, their support of the project. Rich Mooi and Christina Piotrowski California. Biological Invasions, 18: 2007–2016. Jones, M.L. 1961. Lightiella serendipita, gen. nov., sp. nov., a cephalocarid (California Academy of Sciences) provided valuable insights to aid from San Francisco Bay, California. Crustaceana, 3: 31–46. with identification and on previous attempts to locate L. serendipita. Jones, M.L. & Hand, C. 1956. On the discovery of a second member of Thanks to Janet Thompson (USGS) for helpful discussion on the the crustacean subclass Cephalocarida. Systematic Zoology, 5: 41–42. Downloaded from https://academic.oup.com/jcb/article-abstract/doi/10.1093/jcbiol/ruaa044/5874902 by Zoological Society of San Diego user on 04 August 2020 original discovery and to USGS SFBE IEL staff, Ashley Loveland, Knox, G.A. & Fenwick, G.D. 1977. Chiltoniella elongata n. gen. et sp. (Crustacea: Cephalocarida) from New Zealand. Journal of Royal Society Jessica Donald, Hannah Mittelstaedt, William Chan, David Nelson, of New Zealand, 7: 425–432. Tanya Graham, Mason Hill, Angelina Ravani, for assistance with Light, S.F. & Carlton, J.T. 2007. The Light and Smith manual: Intertidal collecting and processing the samples that made this rediscovery invertebrates from central California to Oregon. University of possible. Thanks also to the anonymous reviews for their time and California Press. Berkeley, CA, USA. helpful contributions. McLaughlin, P.A. 1976. A new species of Lightiella (Crustacea: Cephalocarida) from the west coast of Florida. Bulletin of Marine Science, 26: 593–599. 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