Lasiopogon willametti Cole & Wilcox

Mcknight, Tristan A. & Cannings, Robert A., 2020, Molecular phylogeny of the genus Lasiopogon (Diptera: Asilidae) and a taxonomic revision of the bivittatus section, Zootaxa 4835 (1), pp. 1-115 : 83-85

Lasiopogon willametti Cole & Wilcox

Lasiopogon willametti Cole & Wilcox, 1938: 77 .

Diagnosis. ( Fig. 33 ) A medium-sized dark brown species from sandy rivers in Oregon and northern California; all setae black except white setae of beard, coxae, femur apex, and tergite sides; thorax tomentum brown, dorsocentral and acrostichal stripes dark brown but indistinct at an angle; tergites with brown tomentum in basal spots, apical grey bands broad. Epandrial halves moderately concave medially; phallus dorsal carina apex dorsoventrally flattened into disc. Ovipositor dark brown/black, acanthophorite spines black.

Redescription. Body length ♂ 9.8–10.7mm; ♀ 10.6–12.8mm. Head. HW ♂ 2.12–2.30mm; ♀ 2.28–2.85mm. FW ♂ 0.47–0.50mm; ♀ 0.52–0.71mm. VW ♂ 0.91–0.94mm; ♀ 0.96–1.17mm. VW/HW = ♂ 0.40–0.44; ♀ 0.41– 0.44. FW/VW = ♂ 0.51–0.54; ♀ 0.53–0.61. VD/VW = ♂ 0.12–0.14; ♀ 0.12–0.16. GH/GL = ♂ 0.33–0.38; ♀ 0.39–0.53. Face and vertex brown. Ventral setae (beard, labium, palps) white; mystax and all dorsal setae black. Occipital macrosetae fine, longest (to 0.7mm) posterior of frons, moderately curved anterolaterally, lateral macrosetae reduced to short fine setae. Frontal setae moderate, reach to end of scape; orbital setae gently curving over eye margin; ocellar setae fine, short, indistinct amidst other setae. Antennae. Black, with thin grey tomentum. Setae black, no setae on postpedicel. Postpedicel relatively long, with straight dorsal and ventral margins; stylus mostly of even width. WPP/LPP = ♂ 0.23–0.28; ♀ 0.25–0.31. LAS/LPP ♂ 0.50–0.60; ♀ 0.57–0.61. Thorax. Prothorax brown, with white setae; postpronotal lobes brown, the lateral angle chestnut, setae mixed white and black. Scutum tomentum brown, rarely grey. Dorsocentral stripes darker brown, indistinct when viewed from an angle; acrostichal stripes dark brown. All setae of scutum black; dorsocentral macrosetae fine, lateral macrosetae strong. Anterior dorsocentral macrosetae 3–8, longest to 1.0mm, indistinct among finer setae, posteriors 5; postalars 2–4; supra-alars 2–3; presuturals 2–3; posthumerals 0–2. Scutellar tomentum brown; rim inflated, leaving a semi-circular line impressed inside the dorsal edge; apical macrosetae black, moderately fine, 8–10 on each half, mixed with other setae. A few short setae pointing straight up on uppermost edge of rim. Pleural tomentum brown dorsally (rarely grey), grey ventrally. Katatergite macrosetae black, long, 8–9, with a few fine short white setae; katepisternal setae white, fairly long, abundant; anepisternal macrosetae 7–8, black (to 0.8mm), with several short black setae along dorsal margin and a few white setae in posteroventral corner; anepimeron with 1–4 fine white setae. Legs. Base color dark brown/black, covered in yellowish-grey tomentum; bare at joints. No coxal peg. Coxae with white setae; macrosetae of femur, tibia, and tarsi black; fine setae white on basal 70% of femur, apically black. Ventral setae on femur longer than femur width; dorsolateral macrosetae on profemur indistinct amidst abundant fine long setae, mesofemur with 6–8 macrosetae, metafemur with 12–14. Protibia with ventral macrosetae 3 times longer than tibial width; dense apicoventral patch of short setae on protibia pale yellow, indistinct; on metatibia dark brown. Claws chestnut over basal 60%, black apically. Wings. Veins brown; membrane hyaline, but very pale brown when viewed obliquely. DCI = 0.29–0.40. Halter knob cream, without spot, stem brown. Abdomen. Cuticle dark brown/black; thick brown tomentum on tergite bases divided into lateral spots by medial grey tomentum, bands of grey tomentum cover apical 50% of each tergite and extending anteriorly laterally and along midline. Tergite 1 with 4–5 lateral black macrosetae, 1–3 golden macrosetae; lateral setae on tergites 1–3 white and as long as halter, on tergites 4–7 in male white and as long as scape + pedicel, in female black and shorter than scape; dorsal setulae short, black. Sternite tomentum grey, setae white. Male genitalia. Cuticle black, covered in brown-grey tomentum except at base of epandrium and of hypandrium/gonocoxite complex; with long black setae; white setae on cerci; setal brush dark brown. Epandrium elongate, in lateral view the width about 50% the length, widest in basal third, with dorsal and ventral margins straight, apex rounded to short ventral subapical tooth. In dorsal view, medial margins of epandrium moderately curved, curvature starts about 40% from base, outer margins suddenly tapered at apex; basal sclerite prominent. Phallus paramere sheath dorsally about 45% the length of phallus; paramere sheath without ventral ornamentation; dorsal carina broad, rounded, protruding just farther than aedeagal tube and with apex dorsoventrally flattened into disc, leaving a narrow semicircular gap between apices. Ejaculatory apodeme in lateral view moderately bent dorsally in basal third, sometimes slightly recurved at apex, with dorsal carina of fairly even width. Subepandrial sclerite with triangular central unsclerotized area in basal 31%, gradually narrowing to a parallel-sided gap along midline; spines parallel-sided, blunt, sparsely arranged in lateral midsection, dense elsewhere.

Female genitalia. Undissected: Tergite and sternite 8 dark brown/black, with white erect fine setae; lateral lobe with 3–5 strong black setae. Cerci brown with pale setae; acanthophorite spines black.

Type Material. HOLOTYPE (photos examined) ♂ labelled: “[rectangular beige label] Kiger’sIsland/ Ore. IV-19 ‘30”; “[rectangular white label] J. Wilcox/ Coll.”; “[rectangular salmon label] HOLOTYPE / Lasiopogon / willametti/ Cole & Wilcox”; “[rectangular beige label] Lasiopogon / willamettei/ ♂ Type n.sp.”; “[rectangular white label] California Academy/ of Sciences/ Type No. 6443”. CAS.

PARATYPES (109 specimens examined): U.S.A.: OREGON: Benton Co., Corvallis [44.57 -123.256] , 8.v.1929, V.T. Shattuck (1♂ CAS) , 10.v.1930, J. Wilcox (2♂ CAS) , 27.v.1930, R.E. Dimick (1♂ 1♀ CAS) , 2.v.1931, J. Wilcox (1♂ 1♀ CAS) , 15.v.1931, J. Wilcox (2♀ CAS) ; Kiger Island [44.527 -123.238] , 8.iv.1930, J. Wilcox (1♂ 3♀ CAS [allotype included], 2♂ 1♀ EMEC, 1♀ OSUC, OSUC 583680 , 1♀ UCRC, UCRC ENT 449989 , 1♂ 1♀ USNM, USNMENT1100242 – USNMENT1100243 ), R.E. Dimick (1♂ MCZ) , 12.iv.1930, J. Wilcox (4♂ 6♀ CAS, 1♂ CNC CNC 167558, 1♂ FISH, 1♀ MCZ, 1♂ UCRC, UCRC ENT 449986 , 1♀ USNM, USNMENT1100236 ) , 16.iv.1930, J. Wilcox (2♂ 2♀ CAS, 1♀ CNC, CNC 167558, 1♀ WSUC), R.E. Dimick (3♂ 1♀ CAS) , 19.iv.1930, J. Wilcox (8♂ 5♀ CAS, 2♂ 2♀ FISH, 1♀ LACM, LACM ENT 334066 , 1♂ LEM LEM-0113911 , 1♀ MCZ, 1♀ RBCM, 1♂ 1♀ UCRC, UCRC ENT 449987 – UCRC ENT 449988 , 2♂ 1♀ 1? USNM, USNMENT1100237 – USNMENT1100240 ), R.E. Dimick (3♂ 1♀ CAS, 1♂ FISH, 2♂ 2♀ MCZ, MCZ 19433, 1♂ OSUC, OSUC 583679 , 1♂ RBCM, 1♂ USNM, USNMENT1100241 ) , 3.v.1930, J. Wilcox (2♂ CAS) , 23.v.1930, J. Wilcox (1♀ USNM, USNMENT1100235 ) , 27.v.1930, J. Wilcox (1♂ 1♀ CAS, 1♂ USNM, USNMENT1100244, 1♂ WSUC) , 16.iv.1931, R.E. Dimick (1♀ CAS) , 3.v.1931, J. Wilcox (1♀ CAS, 1♂ USNM, USNMENT1100245) ; Linn Co., Albany [44.639 -123.112] , 15.v.1931, J. Wilcox (2♂ 1♀ CAS) ; Crabtree [44.637 -122.928] , 15.v.1931, J. Wilcox (2♂ 5♀ CAS) ; Lebanon [44.5377 -122.8888] , 27.v.1931, J. Wilcox (1♂ 2♀ CAS) ; Yamhill Co., Wheatland [45.091 -123.046] , 10.v.1931, J. Wilcox (1♂ CAS) .

Other Material Examined (104 specimens). U.S.A.: CALIFORNIA: Del Norte Co., Jedediah Smith Redwoods SP, Howland Hill Rd nr Cedar Creek bridge, 41.7893 -124.0779, 13.v.2015, T.A. McKnight (1♂ [1 EtOH] UMMZ) ; Humboldt Co., [no locality], 4.v.1911, Oldenberg (2♀ USNM, USNMENT1100248 –USNMENT1100249), 6.v.1911, Oldenberg (1♀ USNM, USNMENT1100247 ) ; Bair’s Ranch, Redwood Creek [40.964 -123.842], 11.vi.1903, H.S. Barber (1♀ EMEC) ; Van Duzen River , 12.iv.1936, B.P. Bliven (1♀ RBCM) , 18.iv.1937, B.P. Bliven (1♀ RBCM) ; IDAHO: Ada Co., Boise, Barber Park [43.56977 -116.13908], 14.iv.1990, G. Stephens (1♂ 1♀ ESUW, 1♀ RBCM) ; OREGON: Benton Co., Corvallis (1♂ EMEC) , 8.vii.1897 (1♀ EMEC) , 9.vi.1897 (1♂ EMEC) , 3.v.1916 (1♂ EMEC) , 14.iv.1930, J. Wilcox (1♀ EMEC) , 27.v.1930, R.E. Dimick (1♂ USNM, USNMENT1100232 ) , 2.v.1931, J. Wilcox (1♂ 1♀ USNM, USNMENT1100233 – USNMENT1100234 ) , 30.iv.1956, W.J. Hogg (2♀ RBCM, RBCM ENT 991-69074 , RBCM ENT 991-86384 ) ; Corvallis , 1 mi S [44.553 -123.255], 6.v.1969, E.M. Fisher (1♂ 3♀ FISH) ; Corvallis, Willamette Park [44.547 -123.243], 31.v.1964, R.J. Lavigne (4♂ 7♀ ESUW) ; Corvallis, Willamette Park, Mary’s River , 9.vi.1964, R.J. Lavigne (3♂ 2♀ [2 pr in cop] ESUW) ; Corvallis, Willamette River sandbars at Kendall Natural Area , 44.54749 -123.24311, 19.v.2012, T.A. McKnight (1♂ RBCM, 1♂ TAM, 4♂ 1♀ [4 EtOH] UMMZ) ; Kiger Island , 8.iv.1930, J. Wilcox (1♂ EMEC) , 10.iv.1930, R.E. Dimick (1♀ EMEC) , 12.iv.1930, J. Wilcox (1♂ EMEC) , 19.iv.1930, I. Wilcox (1♂ EMEC) , J. Wilcox (1♂ 1♀ RBCM, 2♂ 1♀ EMEC), R.E. Dimick (1♂ 1♀ EMEC) ; Kiger Island NE corner, Willamette River , 3 mi SE Corvallis, 44.52681 -123.23809, 19.v.2012, T.A. McKnight (1♂ 1♀ RBCM, 1♂ TAM, 5♂ 1♀ [5 EtOH] UMMZ) ; Mary’s River , 3 mi W Philomath [44.542 -123.4], 26.iv.1956, E.R. Turner (1♂ 1♀ FSCA) ; Deschutes Co., Tumalo State Park, on Deschutes River , 10 km N of Bend, 44.12944 -121.32917, 28.v.1995, R.A. Cannings, H. Nadel (1♀ RBCM) ; Douglas Co., Siskiyou National Forest, Rogue River, Horseshoe Bend [42.680 -123.735], 30.v.2009, J.D. Ledbetter (1♀ MNAZ MNA DIP 12.0052) ; Lane Co., Oakridge , 2 mi NW [43.758 -122.523], 22.v.1953, J.D. Lartin (1♂ EMEC) ; Linn Co., Crabtree [44.637 -122.928], 15.v.1931, J. Wilcox (1♀ FISH) ; Crabtree Creek @ Hwy 226 bridge 8 mi N of Lebanon, 44.65479 -122.85185, 19.v.2012, T.A. McKnight (1♂ 1♀ RBCM, 1♂ 1♀ TAM, 2♂ 5♀ [5 EtOH] UMMZ) ; Marion Co., Willamette Mission State Park, Willamette River sandbars, 4 mi W of Waconda, 45.08213 -123.06181, 18.v.2012, T.A. McKnight (2♂ 1♀ RBCM, 2♂ 1♀ [1 pr in cop] TAM, 9♂ 1♀ [9 EtOH] UMMZ); Polk Co., W Salem, Willamette River bank [44.931 -123.07], 30.iv.1980, R.L. Westcott (1♂ 3♀ RBCM) .

Taxonomic Notes. On the basis of DNA evidence and genitalia morphology, this concept of L. willametti is more strictly circumscribed than previous usage, excluding dark-mystaced specimens of L. ripicola and the northern subspecies of L. willametti now called L. puyallupi . These three species are mostly allopatric but have some areas of overlap and we believe further work should investigate whether they hybridize.

Etymology. No explanation given in the original description, but evidently named for the type locality on the Willamette river, despite Wilcox’s improper use of the singular masculine genitive (-i) instead of a locational adjectival suffix (-ensis).

Distribution ( Fig. 39 ) Nearctic; central Oregon, with some populations extending into extreme northern California and southwestern Idaho. Type Locality: U.S.A.: Oregon: Benton Co., Kiger Island.

Phylogenetic Relationships. Member of bivittatus section, actius group, likely as sister to L. dimicki .

Natural History. Habitat: sandy riversides. Usually found perching on patches of open dry sand above the water ( Fig. 16 ), often near willow ( Salix L.). Dates collected range from April 8 to July 8, with most in April and May. One female pinned with prey: Limoniidae (Diptera) .

Figures

FIGURE 33. Matrix key of Lasiopogon morphology for species revised in this publication, indicating details of tergite tomentum, major setation, and dissected male genitalia. Taxa are grouped on pages with closely related and visually similar species. (33) L. actius, L. dimicki, L. puyallupi stat. nov.

FIGURES 37–40. Distribution maps of georeferenced records for Lasiopogon species revised in this publication, part 1 of 2. Each map corresponds to one page of the morphology tabular key.

FIGURES 14–21. Representative habitats of inland sand-perching Lasiopogon species collected for this revision. (14) Washington: Asotin Co., Snake River, sandy bank 4 mi S of Asotin jct Hwy 129, 21.iv.2014 (L. ripicola). (15) Washington: Thurston Co., Tumwater, Deschutes River @ Pioneer Park, 15.v.2015 (L. puyallupi stat. nov.). (16) Oregon: Linn Co., Crabtree Creek @ Hwy 226 bridge 8 mi N of Lebanon, 19.v.2012 (L. willametti). (17) Washington: Franklin Co., Juniper Dunes Wilderness, N entrance, 18 mi NE of Pasco, 20.iv.2014 (L. albidus). (18) California: Marin Co., San Antonio Creek, San Antonio Rd 4.5 mi S of Petaluma, 15.iii.2014 (L. zonatus, L. esau sp. nov.). (19) California: Riverside Co., Little San Gorgonio Creek @ Potrero blvd bridge, 2 mi NW of Beaumont, 9.iii.2014 (L. wilcoxi sp. nov.). (20) New Mexico: Grant Co., Gila River below Forks campsite, 6.v.2015 (L. karli sp. nov.). (21) California: Riverside Co., Santa Ana River at Mt. Rubidoux, 4.iii.2013 (L. drabicolum).