Orr and Matarese Revison of the genus Lepidopselta Gill, 1862 



577 



Highest densities of larvae occur in the Bering Sea (Fig. 

 24). compared with the western Gulf of Alaska. 



to the gill rakers being more numerous than those of con- 

 generic species. 



Life history 



Lcpiclopsctta collected from the eastern Bering Sea and 

 Sakhalin Island, presumed to be L. polyxystra n. sp., fed pri- 

 marily on polychaetes and other marine worms; molluscs 

 (Skalidn, 1959, 1963: Lang et al., 1995) or fishes, primarily 

 Ammodytes hexapterus in depths >50 m (Lang et al., 1995), 

 were a second significant component of the diet. Feeding 

 took place primarily from May to September, falling to low 

 levels during the winter (Shubnikov and Lisovenko, 1964) 

 when spawning occurs (Fadeev, 1965). Spawning occurs in 

 areas with good water circulation over hard bottoms of 

 sand with gravel and peaks from early March to mid-April 

 in waters off Kamchatka, possibly occurring as late as mid- 

 June in the western Pacific (Pertseva-Ostroumova. 1961). 

 Fecundity ranges from 151,700 to 404,200 eggs (Fadeev, 

 1965). Life history including spawning and development 

 was discussed by Pertseva-Ostroumova (1961, as L. bili/i- 

 eata bilineata) and larval development was described by 

 Okiyama ( 1988, as L. bilineata ). 



The Washington Department of Fisheries reported Lepi- 

 dopsetta from late December through early March in sandy 

 gravel of upper intertidal beaches at several sites in cen- 

 tral and southern Puget Sound (Penttila, 1995). In January 

 1991, one beach site on the south shore of Dana Passage 

 (the center of a relatively large area of documented Lepi- 

 dopsetta spawning) was the source of six batches of field- 

 collected spawned eggs (each about 1 mm in diameter) 

 that were subsequently reared through hatching. We iden- 

 tified the reared larvae as L. polyxystra n. sp. Egg batches 

 ranged in size from 40 to several hundred eggs and were 

 incubated over about 14 days with ambient central Puget 

 Sound water (about 9.0°C3). Larvae hatched between 4 

 and 5 mm and had yellow pigmentation associated with 

 the melanophores. For additional early life history infor- 

 mation, see generic account. 



The maximum recorded age for female L. polyxystra n. 

 sp. captured in the Bering Sea is 18 yr at 49 cm FL, and for 

 males is 17 yr at 40 cm FL (Alton and Sample'"). The gills 

 of adults from the Gulf of Alaska have been found to be 

 heavily infested with copepod parasites Nectobrachia irtdi- 

 visa, and Naobr'anchia occidentalis. previously recorded 

 in Lepidopsetta by Kabata (1988). For both parasites, L. 

 polyxystra n. sp. was significantly more heavily infested 

 thanL. bilineata." The parasites Acanthochondria vancoii- 

 verensis and Haemobaphes sp. were also recorded. 



Etymology 



The specific name polyxystra is derived from the Greek 

 poly, meaning many, and xystrus. meaning raker, referring 



>" Alton, M. A., and T. Sample. 1976. Rock sole (family Pleu- 

 ronectidae). In Demersal fish and shellfish resources of the 

 eastern Bering Sea in the baseline year 1975 (W. T. Pereyra, 

 J. E. Reeves, and R. G. Bakkalal. p. 461-474. Northwest 

 and Alaska Fish. Center Proc. Rep., Seattle. WA. 



Comments 



Under the name of L. bilineata, L. polyxystra n. sp. has been 

 the subject of many studies. Work on specimens collected 

 north of the extreme southeastern Bering Sea and west of 

 the eastern Aleutian Islands in the western North Pacific 

 may be presumed to be based on L. polyxystra n. sp. How- 

 ever, all studies conducted on specimens from the Gulf of 

 Alaska into Puget Sound, regions of extensive overlap in the 

 distributions of L. polyxystra n. sp. and L. bilineata, should 

 be considered applicable at the generic level only, unless 

 voucher specimens were collected and can be verified. 



According to Pertseva-Ostroumova ( 1961), juveniles as 

 small as 20 mm SL have been collected on the bottom. 

 However, the species exhibits much plasticity in settling 

 size, with specimens much greater than 20 mm SL rou- 

 tinely collected in plankton nets. 



A widely published illustration identified as L. bilineata 

 is based on a specimen of L. poly.xystra n. sp. taken off 

 Kodiak Island, Alaska ("St. Paul, Kodiak," USNM 27602), 

 now badly damaged. First published in Goode ( 1884), it was 

 subsequently reprinted in Jordan and Goss (1889), Jordan 

 and Evermann ( 1900 ), Jordan and Starks ( 1906 ), and Ever- 

 mann and Goldsborough (1907) among other publications. 



Acknowledgments 



Beverly Vinter first noticed an unidentified pleuronectid in 

 our ichthyoplankton samples almost 15 years ago. With sup- 

 port from A. W. Kendall Jr, she persisted over the years in 

 her belief that these larvae represented a new species of 

 pleuronectid. We thank her for her insight as well as her 

 identifications, illustrations, measurements, and numerous 

 examinations of larvae. Early in our study, A. W. Kendall Jr 

 arranged for the collection of adults, the rearing of larvae 

 (with D. Misitano, formerly of NWFSC), and electrophoretic 

 analysis of samples (with F. LTtter formerly of NWFSC). 

 Helen Mulligan (first working at AFSC and later on contract 

 to Humboldt State University) made several significant con- 

 tributions to the study including a preliminary analysis of 

 the geographic distribution of larval and adult Lepidopsetta 

 that provided evidence supporting a taxonomic basis for the 

 observed differences in larval shape and structure. Maryjane 

 Cleveland, a domestic fisheries observer, provided detailed 

 notes of her observations of Lepidopsetta, sparking indepen- 

 dent early collections of adult samples. Other samples and 

 data have been provided over the years by the AFSC's RACE 

 Division (W Flerx, G. R. Hoff, R. Macintosh, G. Walters, 

 and K. Weinberg), Resource Ecology and Fisheries Manage- 

 ment Division's Observer Program (S. Barbeaux, M. Brown, 

 S. Corey, K. Kruse, M. Loefflad, R. Narita, N. Raring, and 

 K. Scott I, and by the Alaska Department of Fish and Game 

 (H. Sanborn and D. Urban). Biologists of the Washington 

 Department of Fish and Wildlife, including W A. Palsson, R. 

 Pacunski, and G. Lippert, provided comparative photographs, 

 specimens, and data for the Puget Sound. Jeff Marliave 



