Panthea virginarius Grote

Anweiler, Gary G., 2009, Revision of the New World Panthea Hübner (Lepidoptera, Noctuidae) with descriptions of 5 new species and 2 new subspecies, ZooKeys 9 (9), pp. 97-134 : 121-123

Panthea virginarius Grote

Figs. 29-35 , 50-51 , 62 , 69

Biston virginarius Grote, 1880: 220 .

Lycia virginaria (Grote) ; Dyar 1902: 328.

Panthea virginaria (Grote) ; Barnes and McDunnough 1917: 83; McDunnough 1938: 54; Franclemont and Todd 1983: 134.

Panthea portlandia Grote, 1896: 14 ; Dyar 1902: 98; Smith 1903: 98; Barnes and Mc- Dunnough 1917: 83; McDunnough 1938: 54; Franclemont and Todd 1883: 134. New synonomy.

Panthea angelica Dyar, 1921: 142 ; McDunnough 1938: 54; Franclemont and Todd 1883: 134. New synonomy.

Panthea portlandia suffusa McDunnough, 1942: 94 ; Franclemont and Todd 1883: 134. New Synonomy.

Type material. Biston virginarius : Holotype female, Soda Springs , Shasta Co, California, USA ( BMNH). Photograph examined

Panthea angelica: Mt. Lowe, Los Angeles , California, USA. Holotype male ( USNM) Photograph examined; genitalia slide apparently lost.

Panthea portlandia : described by Grote from 2 specimens from Portland, Oregon, USA. Types could not be located in either the BMNH or USNM and may be lost.

Panthea virginaria suffusa : described from a holotype male from Dixon Creek, Barriere, British Columbia, Canada. The specimen was reared from a larva collected from Picea englemanni . (Type # 5282 in CNC). Adult and genitalic slide examined.

Diagnosis. Panthea virginarius varies greatly in size and color pattern depending on location and habitat. Both sexes of P. virginarius can be very difficult to separate from those of P. gigantea where they occur together unless genitalic characters are used. The tip of the uncus can usually be examined without dissection by brushing the scales from the end of the abdomen; the male of P. gigantea has a bifurcate tip to the uncus ( Fig. 48 ), P. virginarius does not ( Fig. 50 ). Females can be separated by the structure of the sterigma, which is much larger and more massively sclerotized in P. gigantea ( Fig. 60 ) than in P. virginarius ( Fig. 62 ). Black and white specimens of P. virginarius from southern British Columbia and Idaho ( Fig. 35 ) have been mistaken for nominate P. acronyctoides ( Fig. 36 ), but the two taxa are well separated by range ( Figs. 69 , 72 ). In the Rocky Mountains from Alberta and British Columbia southward P. virginarius can be confused with P. acronyctoides nigra . Panthea virginarius is larger and the male has a paler, banded hindwing than nigra; females can be differentiated by examining the ductus, which is wrinkled in P. virginarius ( Fig. 62 ), smooth with an expanded rim around the ostium in nigra ( Fig. 63 ).

Distribution and biology. Panthea virginarius occurs mainly west and north of the Great Basin, from the coast of southern California northward to the Queen Charlotte Islands of British Columbia and the Alaskan Panhandle, eastward to central California, northern Nevada, Idaho, northwestern Wyoming, western Montana, and southwest- ern Alberta; a disjunct population is in the Cypress Hills of Alberta and Saskatchewan ( Fig. 69 ). Large black and white populations (syn. “ portlandia ”) occur along the coast from central California to southern British Columbia. These are replaced by gray and black populations both farther north and farther south along the coast, and at higher elevations inland. Intermediate populations occur at lower elevations eastward as far as western Montana and extreme southwestern Alberta.

Panthea virginarius is found in coniferous forests, in particular but not confined to Douglas-fir forest ( Pseudotsuga menziesii (Mirb.) Franco ) at elevations ranging from sea-level to near tree-line.

Remarks. Panthea virginarius appears in checklists as both the original spelling virginarius (e.g., Grote 1880; Poole 1989) and virginaria (e.g., Franclemont and Todd 1983) with the ending changed from the original spelling for gender congruity. The original spelling is used herein.

The taxonomy of Panthea virginarius has suffered from the same plethora of errors as has occurred elsewhere in the genus, starting with Grote describing virginarius as a geometrid ( Biston ), and finishing with McDunnough describing suffusa as a form of portlandia because the P. virginarius specimens he used for comparison were misidentified specimens of P. acronyctoides nigra .

Panthea angelica is a population of P. virginarius in southern coastal California (Los Angeles and San Bernardino counties). Internally it is identical to nominate virginarius , and externally differs only by being slightly more suffused with dark scales and thus appearing less powdery. The name angelica has been widely misapplied, both in the literature (e.g., Crumb 1956) and on museum specimens of P. greyi and P. acronyctoides nigra , lending weight to the apparently mistaken belief that angelica was a good species.

Panthea portlandia is the name that has been applied to the large and striking black and white coastal populations of P. virginarius that occur mainly at lower elevations from northern California to southwestern British Columbia. Inland, and at higher elevations, this form intergrades with typical P. virginarius , but some of the white shading of the portlandia phenotype is still evident as far east as western Montana and southwestern Alberta. Both white and gray forms occur together at some locations in central Washington. The genitalia are indistinguishable from those of typical P. virginarius , so the name portlandia is also placed in synonymy under P. virginarius .

Panthea portlandia suffusa was described by McDunnough after comparing it to what he believed were specimens of P. virginarius from Colorado and Alberta, but which were in fact specimens of P. acronyctoides nigra . This is evident from his description of the genitalia of P. virginarius , which accurately describes P. acronyctoides , not portlandia ( McDunnough 1942) . An examination of his slides in the CNC confirms this. It also explains his puzzling (but accurate) statement that based on the genitalia slides of males from Colorado and Nordegg, Alberta, P. virginarius seemed to be merely a large western race of P. acronyctoides Walker ( McDunnough 1942) .

Specimens of P. virginarius from northwestern Wyoming tend to be lighter gray, and specimens from Wyoming and adjacent areas of Idaho tend to have the diverticulum of the vesica and its terminal spine greatly reduced in size, and occasionally obsolete.

The various forms of P. virginarius vary greatly in both size and in the proportions of black and white scaling, and thus external appearance varies greatly over a very large geographic area. However, with the exception of specimens in a small area of northwestern Wyoming, little significant variation occurs in the genitalia of either sex, and all are treated as forms rather than subspecies. Further study, particularly in California, may show that one or more populations there should be recognized at the subspecies level, e.g., a silvery-gray population on the Monterey Peninsula that has been reared on Monterey pine ( Pinus radiata D. Don ) (Frank Sala pers. comm.).

The life history of P. virginarius on Vancouver Island, British Columbia. is briefly described by Hardy (1963). The larva and adult female are illustrated in color (as P. portlandia ) by Miller and Hammond (2003), and the larva is described and illustrated in color by Duncan (2006).

Figures

Figures 28-43. Panthea adults 28. P. virginarius ♁, Nevada Co., CA, USA; 29. P. virginarius ♀, Waterton Lk. N.P, AB, CAN; 30. P. virginarius, ♁, LA Co., CA, USA; 31. P. virginarius ♀, Monterey Co, CA, USA; 32. P. virginarius ♁, Lincoln Co., WY, USA; 33. P. virginarius ♀, Cowlitz Co., WA, USA; 34. P. virginarius ♁ - holotype of suffusa, Barriere, BC, CAN; 35. P. viginarius, Vavenby, BC, CAN; 36. P. a. acronyctoides ♁ Edmonton, AB, CAN; 37. P. a. acronyctoides, ♁ holotype of albosuffusa, Queen’s Co., NS, CAN; 38. P.a. acronyctoides ♁, Penobscot, ME, USA; 39. P. a. acronyctoides – a. nigra intermediate, Edmonton, AB, CAN; 40. P. a. nigra ♁ holotype, Gilpin Co., CO., USA; 41. P. a. nigra ♁, Jasper N.P., AB, CAN; 42. P. a. nigra ♁, Grand Co., CO, USA; 43. P. a. nigra ♀, Grand Co. CO, USA.

Figures 50-57. Panthea male genitalia 50. P. virginarius, Josephine Co. OR., USA; 51. P. virginarius Wyoming variant, Lincoln Co., WY., USA; 52. P. acronyctoides nigra, Albany Co., WY, USA; 53. P. a. acronyctoides, Steuben, ME, USA; 54. P. furcilla furcilla, Norfolk Co., MA., USA; 55. P.furcilla australis, Whitfield Co., GA.USA; 56. Panthea f.furcilla - f. australis intermediate specimens, showing variation in size of basal cornuti; a. P.G. Co., MD; b, c. Owsley Co., KY; d. Elko Co., PA. 57. P. greyi. Coconino Co., AZ, USA.

Figures 58-68. Panthea female genitalia 58. P. apanthea, Coconino Co, AZ. USA; 59. P. judyae, Chihuahua, MEX; 60. P. gigantea, Chihuahua, MEX; 61. P. guatemala, Oaxaca, MEX; 62. P. virginarius, Missoula Co., MT., USA; 63. P.acronyctoides nigra, Teller Co., CO., USA;. 64. P. a. acronyctoides, Ashland Co., WI, USA; 65. P. f.furcilla, Windham Co., CT, USA; 66. P. f.furcilla-f. nigra intermediate, Dauphin Co., PA., USA; 67. P. furcilla australis, Whitfield Co., GA, USA; 68. Panthea greyi, Apache Co., AZ., USA.

Fig. 69. Distribution of examined specimens of P. virginarius, P. apanthea and P. judyae.

Figures 44-49. Panthea male genitalia 44. Lichnoptera decora, Queretero, MEX; 45. P. apanthea, El Paso Co., CO., USA; 46. P. judyae Grant Co., NM, USA; 47. P.reducta, Pedemales, DR; 48. P.gigantea, El Dorado Co., CA., USA, a. tip of uncus; 49. P. guatemala, Oaxaca MEX., a. tip of uncus, Oaxaca, b. tip of uncus, Chiapas, MEX.

Fig. 72. Distribution of examined specimens of P. acronyctoides.