taxonID	type	description	language	source
03E187BDC419FFC6DBA3F0CBFA6A9CF8.taxon	description	urn: lsid: zoobank. org: act: D 296 A 360 - 6997 - 43 CD- 9 FCB-C 0 C 58 CEEA 7 F 5 (Fig. 4, Table 3)	en	Larson, Eric R., Abbott, Cathryn L., Gilmore, Scott R., Helbing, Caren C., Lopez, Mark Louie D., Macintosh, Hugh, Stenhouse, Liane M., Williams, Bronwyn W., Usio, Nisikawa (2025): Genome skimming supports two new crayfish species from the genus Pacifastacus Bott, 1950 (Decapoda: Astacidae). Zootaxa 5632 (3): 501-521, DOI: 10.11646/zootaxa.5632.3.4, URL: https://doi.org/10.11646/zootaxa.5632.3.4
03E187BDC419FFC6DBA3F0CBFA6A9CF8.taxon	materials_examined	Type material. Holotype (RBCM 012 - 00086 - 003) male, South Fork of the John Day River, Oregon (44.3981 °, - 119.5472 °). Allotype (RBCM 012 - 00086 - 004) female, South Fork of the John Day River, Oregon (44.3981 °, - 119.5472 °). Other material. RBCM 012 - 00086 - 001, South Fork of the John Day River, Oregon (44.3981 °, - 119.5472 °); RBCM 012 - 00093 - 001, Camas Creek, Oregon (45.0460 °, - 118.9805 °); RBCM 012 - 00094 - 001, North Fork of the John Day River, Oregon (44.9979 °, - 118.9358 °); RBCM 012 - 00095 - 001, Upper Silvies River, Oregon (44.1941 °, - 119.1844 °). Number of specimens by sex in Table 1. Type locality. South Fork of the John Day River, Oregon (44.3981 °, - 119.5472 °).	en	Larson, Eric R., Abbott, Cathryn L., Gilmore, Scott R., Helbing, Caren C., Lopez, Mark Louie D., Macintosh, Hugh, Stenhouse, Liane M., Williams, Bronwyn W., Usio, Nisikawa (2025): Genome skimming supports two new crayfish species from the genus Pacifastacus Bott, 1950 (Decapoda: Astacidae). Zootaxa 5632 (3): 501-521, DOI: 10.11646/zootaxa.5632.3.4, URL: https://doi.org/10.11646/zootaxa.5632.3.4
03E187BDC419FFC6DBA3F0CBFA6A9CF8.taxon	diagnosis	Diagnosis. Pacifastacus with rostrum bearing only single pair of marginal tubercles or spines; acumen length less than 79.4 % of anterior rostrum width; rostrum length less than 18.85 % of TCL (Fig. 3).	en	Larson, Eric R., Abbott, Cathryn L., Gilmore, Scott R., Helbing, Caren C., Lopez, Mark Louie D., Macintosh, Hugh, Stenhouse, Liane M., Williams, Bronwyn W., Usio, Nisikawa (2025): Genome skimming supports two new crayfish species from the genus Pacifastacus Bott, 1950 (Decapoda: Astacidae). Zootaxa 5632 (3): 501-521, DOI: 10.11646/zootaxa.5632.3.4, URL: https://doi.org/10.11646/zootaxa.5632.3.4
03E187BDC419FFC6DBA3F0CBFA6A9CF8.taxon	description	Description. Body and eyes pigmented. Eyes not reduced. Rostrum deflected ventrally, base and anterior broad, margins parallel to sub-parallel, non-serrate; median carina subtle; acumen strongly converging, not separated from remainder of rostrum by spines; acumen length 68 % of anterior rostrum width (11 % sd). Rostrum length including acumen 145 % of basal rostrum width (15 % sd) and 19 % of TCL (2 % sd); anterior rostrum width 82 % of posterior rostrum width (6 % sd). Cephalothorax subcylindrical; postorbital ridge not terminating in spine, occasionally terminating in tubercle; TCL 203 % of carapace width (11 % sd); areola length 273 % of areola width (44 % SD), 34 % of TCL (1 % sd), width 26 % of TCL (5 % sd). Third pereopods without hook on ischium. Chelae without tubercles; palm length 82 % of maximum chela width at palm (5 % sd); palm length 35 % of propodus length (2 % sd); chela height 63 % of maximum chela width at palm (2 % sd). First pleopod (gonopod) of males nondescript, typical for genus. Annulus ventralis lacking, typical for genus. Holotypic male. Body compressed dorsoventrally (Fig. 4 A). Carapace slightly wider (102 %) than abdomen. Rostrum broad, margins parallel to sub-parallel, anterior width 85 % of posterior width, without spines or tubercles, deflected ventrally; with weak median carina (Fig. 4 B). Rostrum length 139 % of posterior width, 18 % of TCL; acumen 30 % of rostrum length. Carapace maximum depth less (85 %) than carapace width; TCL 25.1 mm; areola 200 % longer than wide, 32 % of TCL (Fig. 4 B); short postorbital ridges terminating in small tubercle; surface otherwise lacking tubercles or spines. Abdomen slightly shorter than carapace (97 %). Palm length 87 % of palm width; palm depth 64 % of palm width (all measurements and counts from right chela; Fig. 4 C). Gonopod nondescript, typical for genus (Fig. 4 D, E). Epistome with semi-circular anterior lobe, lacking setae (Fig. 4 F). Right antennal scale 4.1 mm long and 2.0 mm wide (Fig. H). Third pereopods without hook on ischium. Allotypic female. Differing from holotype in following respects: TCL 33.9 mm; areola 286 % longer than wide, length 35 % of TCL; anterior rostrum width 69 % of posterior rostrum width; rostrum length 133 % of posterior width and 17 % of TCL; acumen 34 % of rostrum length; palm length 81 % of palm width, depth 59 % of palm width (all measurements and counts based on right chela). Antennal scale 5.0 mm long, 2.2 mm wide. Annulus ventralis absent (Fig. 4 G). Size. The largest individual measured was 37.6 mm TCL. Color. Olive brown (Fig. 5) to yellow or orange. The white mark at the joint of the dactyl and propodus in P. leniusculus is generally absent or reduced.	en	Larson, Eric R., Abbott, Cathryn L., Gilmore, Scott R., Helbing, Caren C., Lopez, Mark Louie D., Macintosh, Hugh, Stenhouse, Liane M., Williams, Bronwyn W., Usio, Nisikawa (2025): Genome skimming supports two new crayfish species from the genus Pacifastacus Bott, 1950 (Decapoda: Astacidae). Zootaxa 5632 (3): 501-521, DOI: 10.11646/zootaxa.5632.3.4, URL: https://doi.org/10.11646/zootaxa.5632.3.4
03E187BDC419FFC6DBA3F0CBFA6A9CF8.taxon	etymology	Etymology. For the Malheur region of eastern Oregon, including the Malheur National Forest and Malheur Lake, from the French “ malheur ” meaning misfortune. We propose the common name the “ Misfortunate Crayfish ” due to its discovery while studying spread of invasive F. rusticus throughout the John Day River watershed in Oregon, which has displaced P. malheurensis sp. nov. from a substantial proportion of its former distribution.	en	Larson, Eric R., Abbott, Cathryn L., Gilmore, Scott R., Helbing, Caren C., Lopez, Mark Louie D., Macintosh, Hugh, Stenhouse, Liane M., Williams, Bronwyn W., Usio, Nisikawa (2025): Genome skimming supports two new crayfish species from the genus Pacifastacus Bott, 1950 (Decapoda: Astacidae). Zootaxa 5632 (3): 501-521, DOI: 10.11646/zootaxa.5632.3.4, URL: https://doi.org/10.11646/zootaxa.5632.3.4
03E187BDC419FFC6DBA3F0CBFA6A9CF8.taxon	distribution	Geographic distribution and habitat. Pacifastacus malheurensis sp. nov. occurs in the John Day River watershed of central Oregon and its tributary streams, as well as over a watershed divide into the endorheic Harney Basin of southeastern Oregon (Fig. 6). Populations visualized in Fig. 6 are vouchered at the RBCM except the most downstream location in the John Day River and the East Canal at Page Springs Dam population reported in Larson et al. (2016). Harney Basin tributaries include the upper Silvies River and East Canal at Page Springs Dam, an irrigation-modified tributary of the Donner und Blitzen River. Both the Silvies and Donner und Blitzen rivers drain to the saline Malheur Lake. Whether P. malheurensis sp. nov. occurs in other rivers of the Blue Mountains in northeast Oregon, or other endorheic watersheds of the Great Basin of California, Idaho, Oregon, or Nevada, is unknown. Pacifastacus malheurensis sp. nov. has never been detected west of the Cascade Mountains in coastal California, Oregon, or Washington. Pacifastacus malheurensis sp. nov. has not been collected from lentic ecosystems, but natural lakes are scarce within its distribution excluding saline lakes of endorheic basins that are unlikely to be viable for these crayfish.	en	Larson, Eric R., Abbott, Cathryn L., Gilmore, Scott R., Helbing, Caren C., Lopez, Mark Louie D., Macintosh, Hugh, Stenhouse, Liane M., Williams, Bronwyn W., Usio, Nisikawa (2025): Genome skimming supports two new crayfish species from the genus Pacifastacus Bott, 1950 (Decapoda: Astacidae). Zootaxa 5632 (3): 501-521, DOI: 10.11646/zootaxa.5632.3.4, URL: https://doi.org/10.11646/zootaxa.5632.3.4
03E187BDC419FFC6DBA3F0CBFA6A9CF8.taxon	discussion	Life history. Life history of P. malheurensis sp. nov. has not been studied, and berried or ovigerous individuals are not included among the RBCM vouchers. Pacifastacus malheurensis sp. nov. life history might be expected to broadly resemble other crayfishes of the genus Pacifastacus, as slower-growing and with lower fecundity proportional to carapace length relative to members of the family Cambaridae native to eastern North America (Momot 1984).	en	Larson, Eric R., Abbott, Cathryn L., Gilmore, Scott R., Helbing, Caren C., Lopez, Mark Louie D., Macintosh, Hugh, Stenhouse, Liane M., Williams, Bronwyn W., Usio, Nisikawa (2025): Genome skimming supports two new crayfish species from the genus Pacifastacus Bott, 1950 (Decapoda: Astacidae). Zootaxa 5632 (3): 501-521, DOI: 10.11646/zootaxa.5632.3.4, URL: https://doi.org/10.11646/zootaxa.5632.3.4
03E187BDC419FFC6DBA3F0CBFA6A9CF8.taxon	conservation	Conservation status. Pacifastacus malheurensis sp. nov. has likely been displaced from much of its native range in the John Day River of Oregon by ongoing spread of invasive F. rusticus (Messager & Olden 2018; Olden et al. 2009). Urgent conservation attention is needed, with an emphasis on preventing invasive crayfish introductions to isolated P. malheurensis sp. nov. populations in the Silvies River and Donner und Blitzen River. The rapid pace of the spread of F. rusticus, and associated displacement of P. malheurensis sp. nov. from the John Day River, suggests an International Union for the Conservation of Nature (IUCN) status of globally Endangered due to likely range declines of ≥ 70 % over 10 years or three generations (IUCN 2012). As only six occurrences of P. malheurensis sp. nov. are known (Fig. 6), an Oregon natural heritage ranking of Imperiled is recommended (https: // inr. oregonstate. edu / orbic / rare-species / ranking-definitions).	en	Larson, Eric R., Abbott, Cathryn L., Gilmore, Scott R., Helbing, Caren C., Lopez, Mark Louie D., Macintosh, Hugh, Stenhouse, Liane M., Williams, Bronwyn W., Usio, Nisikawa (2025): Genome skimming supports two new crayfish species from the genus Pacifastacus Bott, 1950 (Decapoda: Astacidae). Zootaxa 5632 (3): 501-521, DOI: 10.11646/zootaxa.5632.3.4, URL: https://doi.org/10.11646/zootaxa.5632.3.4
03E187BDC419FFC6DBA3F0CBFA6A9CF8.taxon	discussion	Crayfish associates. Faxonius rusticus is now the dominant crayfish throughout much of the John Day River and its tributaries in Oregon (Messager & Olden 2018; Olden et al. 2009). Pacifastacus malheurensis sp. nov. was not collected in sympatry with F. rusticus by Larson et al. (2012) or Larson et al. (2016). Pacifastacus leniusculus was collected from the mainstem John Day River in the town of John Day by Larson et al. (2012) and included in phylogenetic and morphological analyses here (Table 1). These P. leniusculus did not co-occur with P. malheurensis sp. nov. and mtDNA haplotypes of the two lineages have never been recovered from the same location. Pacifastacus connectens is also known from some locations in the Harney Basin of eastern Oregon, which constitutes its western range boundary, but P. connectens has not been collected with P. malheurensis sp. nov. and is known instead from isolated springs in the vicinity of Harney Lake (Egly & Larson 2018; Principe et al. 2021). Relationships and comparisons. Pacifastacus malheurensis sp. nov. is morphologically similar to P. okanaganensis sp. nov. and P. l. klamathensis crayfishes of coastal, southwestern Oregon and northwestern California. Pacifastacus malheurensis sp. nov. generally has an acumen length less than 79.4 % of anterior rostrum width, whereas P. leniusculus generally has an acumen length greater than 79.4 % of anterior rostrum width (Fig. 3). Pacifastacus malherensis sp. nov. generally has a rostrum length less than 18.85 % of TCL, whereas P. okanaganensis sp. nov. has a rostrum length greater than 18.85 % of TCL (Fig. 3). Pacifastacus l. leniusculus in particular are easy to differentiate from P. malheurensis sp. nov. by the long, spiny rostrum and chelae with short, convex palms (Hobbs 1972). Pacifastacus malheurensis sp. nov. has not been collected in sympatry with P. okanaganensis sp. nov. or coastally distributed P. l. klamathensis and may be differentiated by geographic range. Pacifastacus connectens can be differentiated from P. malheurensis sp. nov. by a serrated rostrum with many pairs of marginal tubercles or spines and the presence of patches of setae on the dorsal margins of the chelae. Pacifastacus connectens in the Harney Basin often has a distinctive color pattern of orange or red mottling on a yellow background (Principe et al. 2021).	en	Larson, Eric R., Abbott, Cathryn L., Gilmore, Scott R., Helbing, Caren C., Lopez, Mark Louie D., Macintosh, Hugh, Stenhouse, Liane M., Williams, Bronwyn W., Usio, Nisikawa (2025): Genome skimming supports two new crayfish species from the genus Pacifastacus Bott, 1950 (Decapoda: Astacidae). Zootaxa 5632 (3): 501-521, DOI: 10.11646/zootaxa.5632.3.4, URL: https://doi.org/10.11646/zootaxa.5632.3.4
03E187BDC413FFDBDBA3F4A5FF2D9D68.taxon	description	urn: lsid: zoobank. org: act: F 9687 AA 1 - D 8 A 4 - 485 D-A 0 BE- 78 F 56253 E 559 (Fig. 7, Table 3)	en	Larson, Eric R., Abbott, Cathryn L., Gilmore, Scott R., Helbing, Caren C., Lopez, Mark Louie D., Macintosh, Hugh, Stenhouse, Liane M., Williams, Bronwyn W., Usio, Nisikawa (2025): Genome skimming supports two new crayfish species from the genus Pacifastacus Bott, 1950 (Decapoda: Astacidae). Zootaxa 5632 (3): 501-521, DOI: 10.11646/zootaxa.5632.3.4, URL: https://doi.org/10.11646/zootaxa.5632.3.4
03E187BDC413FFDBDBA3F4A5FF2D9D68.taxon	materials_examined	Type material. Holotype (RBCM 012 - 00121 - 003), male, Jewel Lake, British Columbia (49.1827 °, - 118.6000 °). Allotype (RBCM- 012 - 00121 - 004), female, Jewel Lake, British Columbia (49.1827 °, - 118.6000 °). Other material. RBCM 012 - 00100 - 001, Deep Lake, Washington (47.5878 °, - 119.3385 °); RBCM 012 - 00121 - 001, Jewel Lake, British Columbia (49.1827 °, - 118.6000 °); RBCM 012 - 00122 - 011, Blueberry Creek, British Columbia (49.2593 °, - 117.9389 °); RBCM 012 - 00123 - 001, Kettle River, British Columbia (49.1097 °, - 118.9792 °); RBCM 012 - 00124 - 001, Idabel Lake, British Columbia (49.7404 °, - 119.1794 °); RBCM 012 - 00125 - 001, Okanagan Lake, British Columbia (50.1802 °, - 119.4412 °); RBCM 012 - 00304 - 001, Park Lake, Washington (47.5879 °, - 119.3964 °). Number of specimens by sex in Table 1. Type locality. Jewel Lake, Jewel Lake Provincial Park, British Columbia (49.1827 °, - 118.6000 °).	en	Larson, Eric R., Abbott, Cathryn L., Gilmore, Scott R., Helbing, Caren C., Lopez, Mark Louie D., Macintosh, Hugh, Stenhouse, Liane M., Williams, Bronwyn W., Usio, Nisikawa (2025): Genome skimming supports two new crayfish species from the genus Pacifastacus Bott, 1950 (Decapoda: Astacidae). Zootaxa 5632 (3): 501-521, DOI: 10.11646/zootaxa.5632.3.4, URL: https://doi.org/10.11646/zootaxa.5632.3.4
03E187BDC413FFDBDBA3F4A5FF2D9D68.taxon	diagnosis	Diagnosis. Pacifastacus with rostrum bearing single pair of marginal tubercles or spines; acumen length less than 79.4 % of anterior rostrum width; rostrum length more than 18.85 % of TCL (Fig. 3).	en	Larson, Eric R., Abbott, Cathryn L., Gilmore, Scott R., Helbing, Caren C., Lopez, Mark Louie D., Macintosh, Hugh, Stenhouse, Liane M., Williams, Bronwyn W., Usio, Nisikawa (2025): Genome skimming supports two new crayfish species from the genus Pacifastacus Bott, 1950 (Decapoda: Astacidae). Zootaxa 5632 (3): 501-521, DOI: 10.11646/zootaxa.5632.3.4, URL: https://doi.org/10.11646/zootaxa.5632.3.4
03E187BDC413FFDBDBA3F4A5FF2D9D68.taxon	description	Description. Body and eyes pigmented. Eyes not reduced. Rostrum deflected ventrally, base and anterior broad, margins sub-parallel, non-serrate; median carina subtle; acumen strongly converging, separated from remainder of rostrum by weak spines or tubercles; length 62 % of anterior rostrum width (12 % sd). Rostrum length including acumen 150 % of base rostrum width (14 % sd) and 21 % of TCL (2 % sd); anterior rostrum width 75 % of posterior rostrum width (5 % sd). Cephalothorax subcylindrical; postorbital ridge not terminating in spine, occasionally terminating in tubercle; TCL 203 % of carapace width (9 % sd); areola length 33 % of TCL (1 % sd), 233 % of areola width (29 % SD); areola width 29 % of total carapace width (4 % sd). Third pereopods without hook on ischium. Chelae without tubercles; palm length 87 % of maximum chelae width at palm (12 % sd); 36 % of propodus length (10 % sd); chelae height 63 % of maximum chelae width at palm (3 % sd). First pleopod (gonopod) of males nondescript, typical for genus. Annulus ventralis lacking, typical for genus. Holotypic male. Body compressed dorsoventrally (Fig. 7 A). Rostrum broad, deflected ventrally; margins sub-parallel with anterior width 78 % of posterior width, without spines or tubercles; median carina weak (Fig. 7 B). Rostrum length 110 % of posterior width and 16 % of TCL; acumen 34 % of rostrum length. Carapace slightly wider (103 %) than abdomen, maximum depth less (83 %) than carapace width; TCL 27.4 mm; areola 227 % longer than wide, 34 % of TCL (Fig. 7 B); short postorbital ridges terminating in small tubercle, carapace otherwise lacking tubercles or spines. Abdomen slightly longer than carapace (108 %). Palm length 90 % of palm width, palm depth 62 % of palm width (all measurements and counts based on right chela; Fig. 7 C). Gonopod nondescript, typical for genus (Fig. 7 D, E). Epistome with semi-circular anterior lobe, lacking setae (Fig. 7 F). Right antennal scale 4.9 mm long and 1.7 mm wide (Fig. 7 H). Third pereopods without hook on ischium. Allotypic female. Differing from holotype in following respects: TCL 21.7 mm; areola length 34 % of TCL, 228 % longer than wide; anterior rostrum width 77 % of posterior rostrum width; rostrum length 132 % of posterior width, 19 % of TCL, acumen 32 % of rostrum length; palm length 86 % of palm width, palm depth 61 % of palm width (all measurements and counts based on right chela). Antennal scale 3.7 mm long and 1.4 mm wide. Annulus ventralis absent (Fig. 7 G). Size. The largest individual measured at RBCM was 47.0 mm TCL. Color. Olive brown to brick red (Fig. 8). The white mark at the joint of the dactyl and propodus in P. leniusculus is generally absent or reduced.	en	Larson, Eric R., Abbott, Cathryn L., Gilmore, Scott R., Helbing, Caren C., Lopez, Mark Louie D., Macintosh, Hugh, Stenhouse, Liane M., Williams, Bronwyn W., Usio, Nisikawa (2025): Genome skimming supports two new crayfish species from the genus Pacifastacus Bott, 1950 (Decapoda: Astacidae). Zootaxa 5632 (3): 501-521, DOI: 10.11646/zootaxa.5632.3.4, URL: https://doi.org/10.11646/zootaxa.5632.3.4
03E187BDC413FFDBDBA3F4A5FF2D9D68.taxon	etymology	Etymology. From an Okanagan-Salish language place name. We propose the common name of the “ Okanagan Crayfish ” due to the distribution of P. okanaganensis sp. nov. throughout the Okanagan and Thompson plateaus and Okanagan Lake, British Columbia, as well as Okanogan County, Washington, and due to the Okanagan lineage terminology of Larson et al. (2012) and Larson et al. (2016).	en	Larson, Eric R., Abbott, Cathryn L., Gilmore, Scott R., Helbing, Caren C., Lopez, Mark Louie D., Macintosh, Hugh, Stenhouse, Liane M., Williams, Bronwyn W., Usio, Nisikawa (2025): Genome skimming supports two new crayfish species from the genus Pacifastacus Bott, 1950 (Decapoda: Astacidae). Zootaxa 5632 (3): 501-521, DOI: 10.11646/zootaxa.5632.3.4, URL: https://doi.org/10.11646/zootaxa.5632.3.4
03E187BDC413FFDBDBA3F4A5FF2D9D68.taxon	distribution	Geographic distribution and habitat. Pacifastacus okanaganensis sp. nov. has been most often collected from relatively isolated, mid-elevation lakes in the Okanagan and Thompson plateaus of British Columbia and Washington (Fig. 6). The species has also been collected from large Okanagan Lake in British Columbia, and lakes below Dry Falls in central Washington at Sun Lakes State Park (Deep and Park lakes). The only lotic records for the species are from the Kettle River and Blueberry Creek in British Columbia. Blueberry Creek was sampled as the outlet stream immediately below Nancy Greene Lake in Nancy Greene Provincial Park. Whether the species was more prevalent in the mainstem Columbia River before invasion of F. virilis is unknown (Larson et al. 2010). Fish and Trout lakes in Washington, documented by mtDNA sequencing in Larson et al. (2012), are the only locations from past sequencing work not vouchered at RBCM (Fig. 6). The eastern range extent of the species into the upper Columbia River watershed of British Columbia, Idaho, and Montana is unknown. Pacifastacus okanaganensis sp. nov. has never been detected west of the Cascade Mountains in coastal British Columbia or Washington.	en	Larson, Eric R., Abbott, Cathryn L., Gilmore, Scott R., Helbing, Caren C., Lopez, Mark Louie D., Macintosh, Hugh, Stenhouse, Liane M., Williams, Bronwyn W., Usio, Nisikawa (2025): Genome skimming supports two new crayfish species from the genus Pacifastacus Bott, 1950 (Decapoda: Astacidae). Zootaxa 5632 (3): 501-521, DOI: 10.11646/zootaxa.5632.3.4, URL: https://doi.org/10.11646/zootaxa.5632.3.4
03E187BDC413FFDBDBA3F4A5FF2D9D68.taxon	discussion	Life history notes. Life history of P. okanaganensis sp. nov. has not been studied, and berried or ovigerous individuals are not included among the RBCM vouchers. Pacifastacus okanaganensis sp. nov. life history might be anticipated to broadly resemble other congeners, as slower-growing and with lower fecundity proportional to carapace length relative to members of the family Cambaridae native to eastern North America (Momot 1984).	en	Larson, Eric R., Abbott, Cathryn L., Gilmore, Scott R., Helbing, Caren C., Lopez, Mark Louie D., Macintosh, Hugh, Stenhouse, Liane M., Williams, Bronwyn W., Usio, Nisikawa (2025): Genome skimming supports two new crayfish species from the genus Pacifastacus Bott, 1950 (Decapoda: Astacidae). Zootaxa 5632 (3): 501-521, DOI: 10.11646/zootaxa.5632.3.4, URL: https://doi.org/10.11646/zootaxa.5632.3.4
03E187BDC413FFDBDBA3F4A5FF2D9D68.taxon	conservation	Conservation status. Pacifastacus okanaganensis sp. nov. could be vulnerable to displacement by invasive F. virilis, common in the mainstem Columbia River of Washington (Larson et al. 2010) and recently discovered in this watershed in British Columbia (Phillips 2024). Pacifastacus leniusculus could also threaten P. okanaganensis sp. nov. with displacement, as it has impacted congeners in California (Bouchard 1977; Light et al. 1995; U. S. Fish and Wildlife Service 1988). Pacifastacus okanaganensis sp. nov. is known from more locations than P. malheurensis sp. nov., and many of these locations are relatively isolated, mid-elevation lakes that may be difficult for other crayfish species to spread into without the assistance of human introductions. As the magnitude and timing of displacement of P. okanaganensis sp. nov. by either F. virilis or P. leniusculus in the Columbia River watershed is unknown, we recommend a global IUCN conservation status of data deficient (IUCN 2012). We recommend rankings of Imperiled in both British Columbia and Washington because only four or five occurrences of P. okanaganensis sp. nov. are known from each of these jurisdictions (Fig. 6).	en	Larson, Eric R., Abbott, Cathryn L., Gilmore, Scott R., Helbing, Caren C., Lopez, Mark Louie D., Macintosh, Hugh, Stenhouse, Liane M., Williams, Bronwyn W., Usio, Nisikawa (2025): Genome skimming supports two new crayfish species from the genus Pacifastacus Bott, 1950 (Decapoda: Astacidae). Zootaxa 5632 (3): 501-521, DOI: 10.11646/zootaxa.5632.3.4, URL: https://doi.org/10.11646/zootaxa.5632.3.4
03E187BDC413FFDBDBA3F4A5FF2D9D68.taxon	discussion	Crayfish associates. Pacifastacus okanaganensis sp. nov. was not collected in sympatry with other crayfish species by Larson et al. (2012) or Larson et al. (2016). Both F. virilis and P. leniusculus occur in the vicinity of P. okanaganensis sp. nov. populations, including in the mainstem Columbia River. Relationships and comparisons. Pacifastacus okanaganensis sp. nov. is morphologically similar to P. malheurensis sp. nov. and P. l. klamathensis from coastal, southwestern Oregon and northwestern California. Pacifastacus okanaganensis sp. nov. generally has an acumen length less than 79.4 % of anterior rostrum width, whereas P. leniusculus generally has an acumen length greater than 79.4 % of anterior rostrum width (Fig. 3). Pacifastacus okanaganensis sp. nov. generally has a rostrum length greater than 18.85 % of TCL, whereas P. malheurensis sp. nov. generally has a rostrum length less than 18.85 % of TCL (Fig. 3). Pacifastacus l. leniusculus in particular are easy to differentiate from P. okanaganensis sp. nov. by the long, spiny rostrum and chelae with short, convex palms (Hobbs 1972). Pacifastacus okanaganensis sp. nov. has not been collected in sympatry with P. malheurensis sp. nov. or coastally distributed P. l. klamathensis and may be also differentiated by geographic range.	en	Larson, Eric R., Abbott, Cathryn L., Gilmore, Scott R., Helbing, Caren C., Lopez, Mark Louie D., Macintosh, Hugh, Stenhouse, Liane M., Williams, Bronwyn W., Usio, Nisikawa (2025): Genome skimming supports two new crayfish species from the genus Pacifastacus Bott, 1950 (Decapoda: Astacidae). Zootaxa 5632 (3): 501-521, DOI: 10.11646/zootaxa.5632.3.4, URL: https://doi.org/10.11646/zootaxa.5632.3.4
