|scientific name Melanophila fulvoguttata |
common name Hemlock Borer
In Alberta separation of this and Melanophila drummondi is virtually impossible. Adults of most M. drummondi have 3 raised costa on the elytra, but not in all, some have none. In adults of M. fulvoguttata this feature is lacking. Specimens examined from Alberta range from one or two weak costa to nothing. Material examined from British Columbia usually has 2 or 3 weak costa. Colour patterns are not diagnostic, most specimens have yellow spots, and some have none. The male genitalia are supposed to be diagnostic however, Bright (1987) found the genitalia intermediate in structure in Manitoba and Saskatchewan specimens, and was unable to discriminate the species. In examining the male genitalia, of a few problematic specimens, the fulvoguttata phenotype predominated in spite of specimens having from 0 to 3 costa, and with and without spots. I agree with Bright (1987) in thinking that these species are likely hybridizing. I will go one step further and suggest that the western race drummondi has 'recently' met the eastern race 'fulvoguttata' and in the mountains and foothills, a band of introgression, similar to the pattern seen in some tiger beetles (Frietag 1965). Most of the Alberta material is the Melanophila fulvoguttata phenotype, with drummondi phenotype regularly showing up intermixed with fulvoguttata phenotypes in the mountains and foothill areas.
The life cycle usually takes 1 or 2 years with winter diapause spent, as a mature larva. Pupation occurs in spring or early summer. In Alberta adults may be found on trunks of spruce trees, often around old resinous wounds.
Beetles of Melanophila fulvoguttata are recorded from a variety of conifers including balsam fir, tamarack and spruce in the eastern US and eastern Canada (Bright 1987, Baker 1972). Melanophila drummondi adults are recorded from a variety of conifers including fir, larch, spruce and Douglas fir in the western provinces and western US (Bright 1987, Furniss and carolin 1977).
Combined ranges are from Alaska to Newfoundland south to Arizona in the west and South Carolina in the east (Bright 1987).
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