Montiphylax thor (Nimmo, 1971)

Ruiter, David E. & Mutch, Robert A., 2019, Montiphylax, (Trichoptera, Limnephilidae), a new genus to accommodate the western North American species: Stenophylaxantennatus Banks, 1900, Philocascathor Nimmo, 1971, and Philocascaalba Nimmo, 1977, ZooKeys 845, pp. 153-180 : 161-163

Montiphylax thor (Nimmo, 1971) Figure 7, 8

Philocasca thor Nimmo, 1971: 147-148, figs 143a, b, 545-547, 653.

Notes.

Nimmo (1971) described M. thor from a single specimen collected within Jasper National Park, Alberta. The Barcode of Life project has collected additional males from the Willmore Wilderness in Alberta, ca. 150 km northwest of the M. thor type locality. This Barcode of Life material was compared to the M. thor holotype and found to be the same. To date, females or larvae of M. thor have not been located.

Wiggins and Anderson (1968) mentioned the dark ventral surface of the M. antennatus scape described by Banks (1900) was absent on the Idaho M. antennatus specimen that Banks (1943) described, implying it was present on the M. antennatus type. The darker ventral surface of the antennal scape is present on the Mt. Baker M. antennatus males and females examined here. However, it is absent on our M. albus material, that have a concolorous scape. Montiphylax thor males have a darkened scape with the ventral surface pale - the exact opposite coloration pattern from M. antennatus . The Banks (1943) Idaho specimen was examined and it has the light ventral surface of the scape and upturned, acute parameres of M. thor . Neither Banks (1943) nor Wiggins and Anderson (1968) recognized this Idaho specimen as a new species. Our genetic comparisons of M. antennatus and M. thor also support Nimmo’s conclusion that M. thor is a valid species. Our determination that the Banks (1943) Wallace, Idaho, record represents M. thor extends the M. thor range another 600km farther south along the Rocky Mountains. This also results in M. thor occurring both further north and south than M. albus along the Rockies. Wallace, Idaho, is a historic silver mining city in the South Fork of the Coeur d’Alene River Valley. It is likely the M. thor specimen was collected at higher elevations in the surrounding area.

Description.

Male genitalia (Fig. 8): The dark, conical, ventral sclerite of the phallic apparatus illustrated by Nimmo (1971) is absent from the holotype and the other M. thor specimens examined in this study. It is unknown what the Nimmo (1971) dark ventral sclerite represents. Eighth tergite without dorsal modified spines or projections. Ninth segment annular with tergite narrow and strap-like; remainder of 9th broad in lateral view, directed posteroventrad at ca. a 45 degree angle from the narrow tergite, with tall, narrow inferior appendages nearly fused to 9th. In caudal view, inferior appendages slightly cupped around phallic apparatus and slightly separated mesally. Tenth segment cupped anteriorly, appearing as two hemispheres extending broadly anteriad within the 9th. Tenth segment appears fused mesally along anterior margin. Superior appendages approximately as long as tall, triangular in lateral view directed upward. Intermediate appendages arise ventrally, strongly sclerotized and extending as two long, tapered, parallel projections, curving downward at apex. In posterior view, below the intermediate appendages are paired, curved, narrow projections nearly surrounding the anus. Phallus large, with strongly sclerotized phallicata; membranous endophallus with dorsal, strongly sclerotized band, projected upward and distad apically; strong, thick parameres originate at the base of the dorsal band, extend distally; tapered to acute apex in lateral view and slightly curved upward throughout. Parameres originate dorsolaterally and extend posteriorly ca. 3 times as long as wide; tapering evenly throughout to acute apex in dorsal view. Aedeagal apex a sclerotized tube within an extensile sheath; ending in the bottom of an upward directed sclerotized cup.

Material examined.

Holotype male - Canadian National Collection Type # 10,588, Alpine Meadows, east of Mt. Edith Cavell, Jasper National Park, Alberta, habitat: Mountain Tarn, A. P. Nimmo, 10-12am, 4 July 1975; Alberta, Willmore Wilderness, 53.6858, -119.419, Hilchie & MacAuley, 21 July 2007, 3 males (Bold # 10ABCAD-004, 10ABCAD-006, & 10ANCAD-007).