Gastropoda: Arionidae): New Distributional Records and Reproductive Anatomy
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Western North American Naturalist Volume 64 Number 4 Article 15 10-29-2004 Prophysaon coeruleum Cockerell, 1890, blue-gray taildropper (Gastropoda: Arionidae): new distributional records and reproductive anatomy Kristiina Ovaska Victoria, British Columbia, Canada William P. Leonard Olympia, Washington Lyle Chichester Wellington, Florida Thomas E. Burke Olympia, Washington Lennart Sopuck Sidney, British Columbia, Canada See next page for additional authors Follow this and additional works at: https://scholarsarchive.byu.edu/wnan Recommended Citation Ovaska, Kristiina; Leonard, William P.; Chichester, Lyle; Burke, Thomas E.; Sopuck, Lennart; and Baugh, Jim (2004) "Prophysaon coeruleum Cockerell, 1890, blue-gray taildropper (Gastropoda: Arionidae): new distributional records and reproductive anatomy," Western North American Naturalist: Vol. 64 : No. 4 , Article 15. Available at: https://scholarsarchive.byu.edu/wnan/vol64/iss4/15 This Note is brought to you for free and open access by the Western North American Naturalist Publications at BYU ScholarsArchive. It has been accepted for inclusion in Western North American Naturalist by an authorized editor of BYU ScholarsArchive. For more information, please contact [email protected], [email protected]. Prophysaon coeruleum Cockerell, 1890, blue-gray taildropper (Gastropoda: Arionidae): new distributional records and reproductive anatomy Authors Kristiina Ovaska, William P. Leonard, Lyle Chichester, Thomas E. Burke, Lennart Sopuck, and Jim Baugh This note is available in Western North American Naturalist: https://scholarsarchive.byu.edu/wnan/vol64/iss4/15 Western North American Naturalist 64(4), © 2004, pp. 538–543 PROPHYSAON COERULEUM COCKERELL, 1890, BLUE-GRAY TAILDROPPER (GASTROPODA: ARIONIDAE): NEW DISTRIBUTIONAL RECORDS AND REPRODUCTIVE ANATOMY Kristiina Ovaska1, William P. Leonard2, Lyle Chichester3, Thomas E. Burke4, Lennart Sopuck5, and Jim Baugh6 Key words: Prophysaon coeruleum, distribution, phylogeography, reproductive anatomy, British Columbia, Idaho, Pacific Northwest, Rocky Mountains, Washington. The genus Prophysaon is composed of 9 ical variation is present in Oregon, and the recognized species of slugs native to temper- name P. coeruleum may apply to a species ate forests of western North America (Turgeon complex (Kelley et al. 1999). Herein we report et al. 1998). Differences in the anatomical on previously unknown populations of P. coeru- characteristics of the distal genitalia have been leum from southwestern British Columbia and used to identify 2 species groups (subgenera; northern Idaho. Pilsbry 1948): Mimetarion, which includes P. We collected P. coeruleum during surveys vanattae, P. obscurum, P. fasciatum, and P. for terrestrial gastropods on Vancouver Island, humile; and Prophysaon, which includes the British Columbia, Canada, and in Washington remaining species (P. andersoni, P. boreale, P. and northern Idaho, United States. On Van- coeruleum, P. dubium, and P. foliolatum). The couver Island we carried out time- and area- genus has a disjunct geographic distribution: constrained surveys along 100-m-long and 1- most species occur along the Pacific Coast m-wide transects in different forested habitats from southeastern Alaska to northern Califor- at 3 sites near Victoria (56 transects searched nia, but a few are present in the Rocky Moun- for a total of 72 person-hours) in March and in tains of northern Idaho and western Montana October–November 2002. In northern Idaho (Smith 1943, Pilsbry 1948, Frest and Johannes we visually searched approximately 30 sites for 2000, Leonard et al. 2003). One species (P. a total of ca. 200 person-hours between April humile) is restricted to the Rocky Mountains and October from 1999 to 2002. In Washington portion of the distribution. we conducted surveys on approximately 300 Prophysaon coeruleum Cockerell (1890) is a sites in the eastern Cascade Mountains and on small, poorly known slug of conservation inter- >130 sites between the Cascade Crest and the est with previously known range from western Pacific Ocean. In addition, one of us (TB) had Washington to northwestern California (Pilsbry access to the results of hundreds of surveys 1948, Kelley et al. 1999). The species has been conducted for “survey and manage” mollusks designated as a “survey and manage” species by the U.S. Forest Service on National Forests under the Northwest Forest Plan (USDA For- within those areas. est Service and USDI Bureau of Land Man- To confirm identification, we examined the agement 1994) due to its close association with reproductive system of the specimens with a older forests, few known localities, and lack of stereo-zoom microscope under 7.5–60X mag- information on its natural history and ecology nification (one specimen from site 2; two spec- (McGraw et al. 2002). Considerable geograph- imens from site 3 in Appendix). Specimens 14180 Clinton Place, Victoria, British Columbia V8Z 6M1, Canada. 2223 Foote Street NW, Olympia, WA 98502, USA. 32805 Greenbriar Boulevard, Wellington, FL 33414, USA. 44715-61st Avenue NE, Olympia, WA 98516, USA. 51759 Colburne Place, Sidney, British Columbia V8L 5A2, Canada. 62018 Dry Creek Road, Ellensburg, WA 98926, USA. 538 2004] NOTES 539 Fig. 1. Distribution map for locality records of Prophysaon coeruleum: solid circles = this study (numbers correspond to those in Appendix); open circles = previous localities (Pilsbry 1948, Branson and Branson 1984). were deposited in collections at the Carnegie several years). The species appears to have a Museum (CM), at the Royal British Columbia very restricted distribution in Canada. Museum (RBCM), and in the personal collec- In Idaho we found P. coeruleum at 2 of tion of T. Burke. Some specimens were sent to approximately 30 sites surveyed. The 2 sites Dr. Thomas Wilke at George Washington Uni- were about 30 km apart in the Couer d’Alene versity to be included in a genetic study. Lake watershed. These observations extend In British Columbia we found P. coeruleum the species’ known range approximately 400 along 2 of the 56 transects searched. These km eastward and represent the 1st records for localities were about 500 m apart on Rocky the Rocky Mountains (Fig. 1). Apparently, the Point Peninsula in the District of Metchosin, population in Idaho is disjunct from the more about 20 km southwest of Victoria on Vancou- western populations, as the intervening Colum- ver Island (records 1–2 in Appendix). These bia Basin consists of arid shrub-steppe habitat records extend the known distribution of the unsuitable for forest-dwelling gastropods (Bar- species approximately 120 km northwest from nosky et al. 1987, Franklin and Dyrness 1988). Washington State and represent the 1st records Brunsfeld et al. (2001) and Layser (1980) pro- from Canada (Fig. 1). Since 1999, two of us (KO vided numerous examples of fungi, plants, and and LS) have carried out surveys for forest- animals that have Pacific coastal and interior dwelling gastropods throughout Vancouver Rocky Mountain distributions, which mirror Island and on the southern coastal mainland of the distribution of western hemlock forest. British Columbia without locating this species Leonard et al. (2003) reported on a previously (about 170 sites surveyed, some intensively over undocumented example of the slug Prophysaon 540 WESTERN NORTH AMERICAN NATURALIST [Volume 64 dubium, Cockerell, from Idaho and cited addi- Externally, our specimens conform to the tional examples of invertebrates that have sim- description in Pilsbry (1948): live animals were ilar disjunct distribution patterns. gray with light blue flecking, the prominence In Washington we found P. coeruleum at 2 of which varied among localities. On all of the sites in the Cispus River watershed and at 1 specimens distinct, longitudinal grooves were site on Pin Creek, a tributary to the lower present on the foot behind the mantle, and the Columbia River. The slugs appeared to be foot margin was narrow with a distinct border most abundant at the Kraus Ridge site in the above (Fig. 2). The extended length of the Cispus watershed (record 5 in Appendix; 11 specimens ranged between 23 mm and 30 mm detections). One of us (TB) has found P. when alive and 12.5 mm and 15 mm after coeruleum at this site on several previous preservation. occasions. The Iron Creek site (record 6 in The genitalia of the new specimens from Appendix) is about 4 km southwest of the Idaho and British Columbia resemble those of Kraus Ridge site and on the opposite side of P. coeruleum from Washington illustrated by the Cispus River. In several visits we have Pilsbry (1948; Figure 378d), except that the found only a single specimen of P. coeruleum penis is much larger; in 1 of the 2 Idaho speci- at this site. There is a 3rd site in this area, mens it is almost as large as the muscular por- approximately 7 km northeast of the Kraus tion of the epiphallus (Fig. 3). Most of the long, Ridge site at 442 m elevation, from which a slender portion of the epiphallus is in a tangle single P. coeruleum was collected on 14 Novem- immediately anterior to the muscular portion. ber 2001. The specimen was identified by Tom The ovotestis is large and consists of approxi- Kogut, Cowlitz Ranger District biologist, but mately 24 egg-shaped lobules, with little pig- was not collected (T. Kogut personal commu- ment. The albumen gland is a small, appendix- nication). The species appears to have a very like structure at the terminus of the common restricted distribution in Washington. duct; it is not clearly demarcated from the com- Surveys by the U.S. Forest Service and U.S. mon duct either by color or texture, at least in Bureau of Land Management found no addi- the preserved animals. The duct of the semi- tional sites in Washington but found several nal receptacle is very long and slender and localities for the species in western Oregon loosely adherent to the common duct. The and also extended its range into northern Cali- vagina is slender and long, as is the entire fornia. However, because similar, undescribed common duct. species have also been found in the southern Interestingly, the genitalia of the new spec- Oregon Cascades (Kelley et al.