Heterischnus coloradensis (Cushman)

Claridge, Brandon, 2021, Revision of Nearctic Heterischnus Wesmael, 1859 (Hymenoptera, Ichneumonidae, Ichneumoninae, Phaeogenini), Journal of Hymenoptera Research 85, pp. 57-79: 57

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Heterischnus coloradensis (Cushman)


Heterischnus coloradensis (Cushman)  

Figs 4 View Figure 4 , 5 View Figure 5 , 6 View Figure 6

Ischnopsidea coloradensis   Cushman, 1920: 253. Holotype: ♀ [USNM]. Not examined.


Heterischnus coloradensis   (Cushman) is chromatically and morphologically similar to H. huardi   but can be distinguished from the latter and other Nearctic species by a combination of the following: 1) male clypeus dark reddish-brown to black; 2) flagellomeres 10/11-12/13 dorsally white in female; 3) supra-antennal area rugulose-punctate; and 4) first lateral area of propodeum rugulose-punctate.


Female (Fig. 4 View Figure 4 ). Body length: 6.8-8.7 mm. Fore wing length: 4.2-5.1 mm.

Color. Head black. Mandible yellowish-white with brown apex. Antenna dark brown with flagellomeres 10/11-12/13 dorsally white. Mesosoma black with following areas white: occasionally anterior margin of pronotum (25% of specimens), posterior 0.2 of dorsal margin of pronotum, usually subalar prominence (60% of specimens), and tegula. Fore and middle legs light brownish-red except for tarsomere 5 brown. Hind leg brownish-red except for basal 0.1 of tibia white, apical 0.2 of tibia brown, tarsomeres brown. Metasoma black to dark brown. Wing membrane clear; basal 0.1-0.2 of wing with veins white, remaining sections brown.

Head. Clypeus smooth, basally with fine punctures separated by 0.5-1.0 × their diameter becoming less dense apically; ventral margin with sublateral apical projections subobsolete to obsolete. Malar space 1.5-2.0 × basal mandibular width. Supraclypeal area rugulose-punctate. Gena smooth, coarsely punctate with punctures separated by 0.2-1.5 × their diameter. Supra-antennal area rugulose-punctate. Vertex smooth, finely punctate with punctures separated by 0.5-2.0 × their diameter. Antenna with 32-34 flagellomeres.

Mesosoma. Mesonotum smooth, with punctures separated by 0.5-2.0 × their diameter. Scutellum smooth, finely punctate with punctures separated by 1.0-2.0 × their diameter. Mesopleuron densely, coarsely punctate with punctures confluent to separated by about 0.5 × their diameter becoming more sparse dorsally; tendency in some specimens to form lateral rugulae. Speculum coarsely punctate dorsally, smooth ventrally. Ventral division of metapleuron rugulose-punctate. Dorsal division of metapleuron with a few scattered punctures. Propodeum overall rugulose-punctate with areola and posterodorsal face rugulose; carination complete. Tarsal claws simple.

Metasoma. Postpetiole rugulose-punctate. T2 length 1.0-1.2 × posterior width. T2-7 granulate with dense, shallow punctures; punctation becoming sparser and indistinct posteriorly. Gastrocoelus rugulose-granulate. Thyridium distant from T2 anterior margin by 0.5-2.0 × thyridial length.

Male (Fig. 5 View Figure 5 ). Body length 6.8-9.1 mm. Fore wing length: 4.3-5.6 mm. As in female except for: yellowish-white markings on mesosoma more extensive.

Material examined.

Paratype: USA • 1♀; Colorado, Larimer Co., Forrester’s; 19.vii.1895; C. F. & N. E. Baker; USNM paratype 22850   .

Non-type material: USA • 1♀; California, Modoc Co. 1 mile N of Stough Reservoir ; [41.5767, -120.2538], 15.vi.1963; UCDC GoogleMaps   1♀; California, Modoc Co., Cedar Pass ; [41.5623, -120.2688]; 29.vi.1955; D. L. Dahlsten; UCDC GoogleMaps   1♀; California, Nevada Co., Sagehen Cr. near Hobart Mills ; [39.4342, -120.2048]; 15.vii.1964; M. E. Irwin; UCRCENT529785 GoogleMaps   1♀; Colorado, Grand Co., Phantom Valley, Rocky Mountain National Park ; 9400 ft; [40.2833, -105.8505]; 16.vi.1948; H., M., G.,D. & J. Townes; EMUSENT00000417 GoogleMaps   1♀, 3♂♂; Colorado, Routt Co., Steamboat Springs ; [40.4857, -106.8309]; 6.viii.1948; H., M., G.,D. & J. Townes; EMUSENT00000722, EMUSENT00000132, EMUSENT00000207, EMUSENT00000073 GoogleMaps   1♂; same collection data as preceding; 5.viii.1948; EMUSENT00000345 GoogleMaps   1♂; Idaho, Oneida Co., 3 mi. S of Roy Summit ; [42.2635, -112.7653]; 6.vii.1972; G. F. Knowlton; EMUSENT00000137 GoogleMaps   1♂; Idaho, Blaine Co., 9 mi. SW Bellevue ; [43.3353, -114.2901]; 28.viii.1965; J. S. Buckett; UCDC GoogleMaps   1♀; Idaho, Boise Co., Idaho City ; [43.82813, -115.8341]; 9.vi.1978; H. & M. Townes; EMUSENT00000777 GoogleMaps   3♀♀; same collection data as preceding; 13.vi.1978; EMUSENT00000258, EMUSENT00000317, EMUSENT00000225 GoogleMaps   1♀♀; same collection data as preceding; 14.vi.1978; EMUSENT00000192 GoogleMaps   2♂♂; Idaho, Custer Co., nr. Stanley ; [44.2161, -114.9353]; 2.viii.1978; H. & M. Townes; EMUSENT00000253, EMUSENT00000206 GoogleMaps   1♂; same collection data as preceding; 7.viii.1978; EMUSENT00000288 GoogleMaps   2♂♂; same collection data a preceding; 8.viii.1978; EMUSENT00000719, EMUSENT00000297 GoogleMaps   1♀; Idaho, Oneida Co., Rock Creek ; [42.4320, -114.3054]; 17.vii.1972; G. F. Knowlton; EMUSENT00000138 GoogleMaps   1♂; same collection data as preceding; 6.vii.1972; EMUSENT00000224 GoogleMaps   1♂; Montana, Madison Co., 16 miles S. of Cameron ; [45.0604, -111.6656]; 18.vii.1971; UCDC GoogleMaps   3♀♀; Montana, Gallatin Co., Bozeman ; [45.6771, -111.0428]; 30.vi.1978; R., B. & C. Dasch; EMUSENT00000629, EMUSENT00000056, EMUSENT00000194 GoogleMaps   4♀♀; same collection data as preceding; 7.vii.1978; EMUSENT00000193, EMUSENT00000077, EMUSENT00000566, EMUSENT00000357 GoogleMaps   1♂; Nevada, Elko Co., Elko ; [40.8385, -115.7628]; 21.viii.1964; F. S. Buckett; UCDC GoogleMaps   1♀; Nevada, Elko Co., Tuscarora ; [41.3146 -116.2233]; 5.vi.1978; H. & M. Townes; EMUSENT00000393 GoogleMaps   1♀; Nevada, Storey Co., Virginia City ; [39.3093, -119.6499]; 14.vi.1951; W. J. Wall; UCDC GoogleMaps   1♀; Oregon, Union Co., Mt. Emily ; [45.4379, -118.0913]; 03-11.vi.1987; T. R. Torgersen, EMUSENT00000420 GoogleMaps   1♀; Utah, Box Elder Co. Willard Peak.; 9000 ft; [41.4210, -112.0561]; 25.vii.1960; G. E. Bohart; EMUSENT00000347 GoogleMaps   2♀♀; Utah, Cache Co., Black Smith Fork Canyon ; [41.6278, -111.8040]; 1-6.vii.1964; W. J. Hanson; EMUSENT00000391, EMUSENT00000108 GoogleMaps   1♀; Utah, Cache Co., North Logan ; [41.7706, -111.8045]; 25-31.v.1983; C. R. Nelson; EMUSENT00000030 GoogleMaps   1♂; Utah, Cache Co., Tony Grove ; 2290 m; 41.8884, -111.6571; 18.v.-1.vi.2019; B. Claridge; Malaise trap; EMUSENT00000547 GoogleMaps   1♀; Utah, Cache Co., Tony Grove Canyon ; [41.8902, -111.6371]; 25.viii.-2.ix.1976; W. J. Hanson; EMUSENT00000026 GoogleMaps   1♂; Wyoming, Albany Co., Pole Mountain ; 41.22, -105.45; 13-20.vii.2013; Malaise trap, ungrazed short grass prairie; L. Haimowitz, H, Aguirre; EMUSENT00004739   .

Distribution and biology.

Collecting dates span mid-May to early September, although the greatest number of records are from July and August. Heterischnus coloradensis   occurs from the Rocky Mountains west to the eastern slopes of the Sierra Nevada Range (Fig. 6 View Figure 6 ). Throughout its range, H. coloradensis   is sympatric with H. huardi   . No host information is known.


In addition to the examined paratype, a specimen that was compared with the holotype by Henry Townes was examined.