Lasiopogon actius Melander

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 : 31-34

Lasiopogon actius Melander

Lasiopogon actius Melander, 1923: 138 .

Diagnosis. ( Fig. 33 ) A medium-sized pale species from the beach dunes of Oregon, Washington and British Columbia; most setae white except macrosetae black along sides of scutum and on lower leg segments, some individuals also with black macrosetae in dorsocentral, occipital, and ocellar groups; tergites with basal brown tomentum usually as lateral spots (especially in female) but occasionally as a dark band; apical 40% of each tergite covered in grey tomentum. Epandrial halves moderately concave medially, with long white setae; phallus dorsal carina protruding with apex swollen into rounded process. Ovipositor dark brown/black, acanthophorite spines black.

Redescription. Body length ♂ 9.2–12.4 mm; ♀ 9.7–12.4 mm. Head. HW ♂ 1.99–2.58mm; ♀ 2.03–2.52mm. FW ♂ 0.45–0.57mm; ♀ 0.48–0.59mm. VW ♂ 0.78–1.05mm; ♀ 0.79–0.95mm. VW/HW = ♂ 0.39–0.42; ♀ 0.37– 0.40. FW/VW = ♂ 0.53–0.58; ♀ 0.59–0.62. VD/VW = ♂ 0.13–0.18; ♀ 0.16–0.17. GH/GL = ♂ 0.38–0.41; ♀ 0.30–0.43. Face with silver-yellow tomentum; vertex with silver/light brown tomentum. Mystax, frontal, and most orbital and occipital setae straw-colored; a few black occipital macrosetae behind eye; beard and labial setae white. Occipital macrosetae relatively straight and of average length, those behind the dorsomedial angle of the eye 0.6mm long and most curved; lateral and ventral macrosetae shorter, straighter. Frontal and orbital setae fine and long.

Antennae. Black, base of postpedicel dark brown; Setae usually straw-colored, no setae on postpedicel. Postpedicel rectangular, stylus broadly tapering. WPP/LPP = ♂ 0.27–0.34; ♀ 0.30–0.36. LAS/LPP = ♂ 0.71–0.76; ♀ 0.60–0.75. Thorax. Prothorax light grey/brown, setae white; postpronotal lobes grey to brownish grey, lateral angle ferruginous, setae white. Scutum tomentum grey/tan, darker around the perimeter. Dorsocentral stripes dark brown; acrostichal stripes absent, cuticle subshining. Dorsocentral macrosetae and shorter setae straw-colored, some dorsocentral macrosetae occasionally black; lateral macroseta groups black, some postalars occasionally straw-colored. Anterior dorsocentral macrosetae 8 (to 1.0mm), mixed with finer setae; 5 posteriors. Postalars 2–5, with a few shorter setae; supra-alars 2–4; presuturals 2–4; posthumerals 1–2. Scutellar tomentum yellow; rim inflated, leaving a semi-circular line impressed inside the dorsal edge; apical macrosetae straw-colored, very abundant (10+ on each side) and mixed with many other long setae. Pleural tomentum gold. Katatergite macrosetae straw-colored, 8–13, with a few weaker setae; katepisternal setae sparse, moderately long, white; anepisternal setae 6–9, relatively strong (to 0.8mm) and mixed with other short setae, a patch of short white setae on dorsal margin of sclerite; anepimeron with 1–3 short wispy setae. Legs. Cuticle dark brown to black, tomentum grey. No coxal peg. Macrosetae on femur usually white, sometimes brown, macrosetae of tibia and tarsi dark brown/black; all finer setae white. Ventral setae on femur dense, longest are longer than femur width. Dorsolateral macrosetae mixed with finer setae: 8–11 on profemur but difficult to distinguish from surrounding finer setae, macrosetae more prominent on mesofemur (4–8) and metafemur (12–18). Protibia with ventral macrosetae about 4 times longer than tibial width. Claws dark brown over basal 60%, apically black. Wings. Veins dark brown; membrane faintly grey from microtrichia. DCI = 0.31–0.42. Halter pale brown, with no spot. Abdomen. Cuticle dark brown/black; subshining brown tomentum at bases of tergites 1–7, bands of grey tomentum cover apical 40–50% of each tergite, extending anteriorly along lateral margins, and in some individuals anteromedially to divide brown into lateral spots (especially in females). Setae yellowwhite/white; all tergites in male with long lateral setae; females with long setae along tergites 1–3 and shorter setae on 4–7. Lateral macrosetae on first tergite 8–9, long but not strongly differentiated from surrounding setae. Sternite tomentum grey; setae long, yellow-white/white. Male genitalia. Epandrium and hypandrium/gonocoxite complex cuticle dark brown; covered in thin grey tomentum except polished medially on hypandrium and sometimes apically on epandrium; with long straw setae, setal brush light brown, dense. Epandrium elongate, in lateral view the width about 45% the length, widest in basal third; apex rounded with ventral tooth. In dorsal view, medial margins of epandrium moderately curved, curvature starts about 35% from base, outer margins gradually tapered; basal sclerite prominent. Phallus paramere sheath dorsally 55% the length of phallus; paramere sheath without ventral ornamentation; dorsal carina divergent from aedeagal tube and extending slightly farther, apex rounded into hemisphere. Ejaculatory apodeme in lateral view strongly to moderately bent dorsally in basal quarter, with broad dorsal carina. Subepandrial sclerite with triangular central unsclerotized area in basal 28% narrowing to a parallel-sided gap in central portion; spines parallel-sided, blunt, densely arranged apically and medially, sparser elsewhere.

Female genitalia. Undissected: Setae white, abundant, erect. Tergite 8 dark brown/black, occasionally lighter at apex; sternite 8 dark brown; lateral lobe setae strong; hypogynial valves with fine setae concentrated basally. Cerci brown/black with pale setae; acanthophorite spines black.

Type Material. LECTOTYPE (examined) ♂ labelled: “[rectangular white label] IlwacoWash/ July 1917 / ALMelander”; “[rectangular red label] TYPE/ Lasiopogon / actius/ Melander”; “[rectangular white and green label] ALMelander/ Collection/ 1961”; “[rectangular beige label] Lasiopogon / actius/ Mel.”; “[rectangular white label] USNMENT01071654”. Our lectotype label “ LECTOTYPE / Lasiopogon actius / Melander/ des. T.A. McKnight 2017 [red, black-bordered label]” has been attached to this specimen. USNM.

PARALECTOTYPES (1 examined): U.S.A.: WASHINGTON: Pacific Co., Nahcotta [46.501 -124.059], 24.v.1917, A.L. Melander (1♂ CNC, CNC 333 ). Our paralectotype label has been attached to this specimen .

Other Material Examined (308 specimens). CANADA: BRITISH COLUMBIA: Haida Gwaii, Graham Island, Masset , 3.vi.1957, E.E. MacDougall (1♂ RBCM, RBCM ENT 991-86248 ); Graham Island , Masset , Skonun Point [54.031 -132.078], 9.vi.1987, D. & J.M. Cooper (1♀ RBCM, RBCM ENT 987-3770 ), 6.vi.1988, J.M. Cooper (1♀ LACM, LACM ENT 334001 , 1♂ 1♀ RBCM, RBCM ENT 991-3647 , RBCM ENT 991-3650 ); Graham Island , Tlell, 53.611278 -131.936351, 25.vi.2009, R. Bennett, M. Connelly, C. & D. Copley, J. Heron, J. Miskelly, (2♂ 2♀ RBCM, RBCM ENT 009-5279 , RBCM ENT 009-5281 – RBCM ENT 009-5283 ), vii.2014 , B. Wijdeven (1♂ [1 EtOH] RBCM) .

U.S.A.: OREGON: [no loc], [?.?.]1929, F.J. Spuijt (1♂ FSCA) ; Clatsop Co., Gerhart Beach [46.031 -123.929], 16.ix.1991, S. & S. Frommer (2♂ 3♀ UCRC) ; Seaside [45.999 -123.929], 29.v.1933, W.W. Baker (4♂ 1♀ CAS) ; Sunset Beach [46.099 -123.942], 6.viii.1938, S.E. Crumb (4♂ 4♀ FSCA) ; Douglas Co., Ziolkouski Beach Park , 2 mi W of Winchester Bay, 43.66264 -124.2067, 16.v.2012, T.A. McKnight (1♂ 1♀ RBCM, 1♂ TAM, 2♂ 2♀ [4 EtOH] UMMZ) ; Lane Co., Baker Beach , dunes behind [44.0853 -124.11778], 27.vi.2012, J.D. Pinto (1♀ UCRC, UCRC ENT 432939 ) ; Florence [44.024 -124.129], 21.vi.1960, E. Ball (1♂ 2♀ FSCA) ; Lincoln Co., Beachside State Park [44.381 -124.089], 11.vi.1988, D.W. Webb (4♂ INHS) ; Devil’s Lake [44.9674 -124.0151], 2.ix.1932, W.W. Baker (1♀ CAS) ; Gleneden Beach, NW tip of Salishan Spit , 44.920078 -124.026942, 17.v.2012, T.A. McKnight (1♂ RBCM, 3♂ 1♀ TAM, 6♂ 3♀ [7 EtOH] UMMZ) ; Governor Patterson State Park , beach, 44.408 -124.085, 24.vi.2006, J.D. Pinto (1♂ UCRC, UCRC ENT 420341 ) ; Newport, S side Yaquinna River mouth, dunes E of South Jetty Rd, 44.612546 -124.069057, 17.v.2012, T.A. McKnight (1♂ 1♀ RBCM, 1♂ [1 EtOH] UMMZ), 21.vi.2013, T.A. McKnight (1♂ [1 EtOH] TAM) ; Waldport [44.4333 -124.0836], 5.vi.1925, H.A. Scullen (1♀ OSUC, OSUC 194365 ) , 7.vi.1925, J.E. Davis (1♂ CAS) , vii.1938, E.C. Van Dyke (1♂ CAS) , 15.vii.1938, E.C. Van Dyke (8♂ 3♀ CAS, 1♂ 1♀ FSCA) ; Tillamook Co., Nehalem Bay , 3 mi S Manzanita [45.6641 -123.9345], 7.vii.1971, J.R. Powers (1♂ 5♀ CAS) ; Pacific City, Bob Straub State Park , dunes W of parking lot, 45.192474 -123.968284, 18.v.2012, T.A. McKnight (1♂ RBCM, 1♂ TAM, 1♂ 1♀ [2 EtOH] UMMZ) ; Rockaway [45.612 -123.946], 27.vi.1920, L.P. Rockwood (1♂ 1♀ USNM, USNMENT1100069 – USNMENT1100070 ) ; Sand Lake [45.288 -123.957], 27.v.1965, C. Henne (4♂ 1♀ CAS) , 7.vii.1962, R.L. Fischer (1♂ MSUC) ; WASHINGTON: Grays Harbor Co., Ocean City State Park , sand dunes [47.032 -124.172], 26–27.v.1996, M. Kippenhan (2♂ 3♀ CSUC) ; Ocean Shores, Taurus Blvd SW [46.9721 -124.1704], 16.v.1994, R.A. Cannings (1♂ 2♀ CSUC, 2♂ 2♀ RBCM) ; Twin Harbor State Park , beach [46.857 -124.114], 22.v.2003, B. Kondratieff, J. Schmidt (1♀ CSUC) ; Westhaven State Park , dunes 2 mi NW of Westport, 46.90241 -124.12839, 20.vi.2013, T.A. McKnight (1♂ 1♀ RBCM, 1♂ 1♀ TAM, 1♂ 1♀ UMMZ) ; Westport [46.887 -124.126], 8.v.1931, J. Wilcox (1♂ CNC) , 8.v.1932, J. Wilcox (4♂ 1♀ CAS, 1♂ CUAC, 1♂ EMEC, 1♂ MCZ), 12.v.1932, J. Wilcox (1♂ OSUC, OSUC 194364 ) , 15.v.1932, J. Wilcox (1♂ 2♀ CAS, 1♀ CUAC, 1♂ MCZ), 17.vii.1932, C.W. Getzendaner (1♀ CAS) , 31.vii.1932, W.W. Baker (4♂ 2♀ CAS, 1♀ CNC, 1♀ EMEC, 1♂ 1♀ FSCA), 24.v.1933, C.H. Martin (1♂ FISH) , 28.v.1933, C.H. Martin (2♂ 1♀ FSCA) , 29.v.1933, C.H. Martin (1♂ ESUW, 3♂ 2♀ FSCA), 18.vi.1933, C.W. Getzendaner (4♂ 4♀ CAS) , W.W. Baker (1♂ FSCA) , 5.vii.1933, G.P. Engelhardt (1♂ CAS) , 7.vii.1933, I. Wilcox (4♂ 7♀ CAS, 1♂ FISH, 1♂ UCRC), J. Wilcox (1♂ BEZA, 13♂ 6♀ CAS, 2♂ 2♀ FISH, 2♂ 4♀ MCZ), W.W. Baker (5♂ 9♀ CAS, 2♂ 2♀ FISH, 1♂ 1♀ FSCA, 1♀ UCRC), 19.vii.1933, W.W. Baker (2♂ CAS, 1♀ FSCA), 5.v.1935, W.W. Baker (1♀ CAS) , 24.vi.1935, C.W. Getzendaner (1♂ 1♀ CAS, 1♀ FISH), 21.vii.1935, C.W. Getzendaner (1♀ BEZA, 5♂ 8♀ CAS, 1♀ FISH), 8.ix.1935, W.W. Baker (2♀ CAS) , 28.iv.1936, J. Wilcox (1♀ CAS) , 16.v.1994, R.A. Cannings (2♀ RBCM) ; Pacific Co., Ilwaco [46.316 -124.067], 28.vi.1925, A.L. Melander (10♂ 11♀ USNM, USNMENT1100773 – USNMENT1100776 , USNMENT1100778 – USNMENT1100781 , USNMENT1100783 – USNMENT1100786 , USNMENT1100788 –USNMENT1100789, USNMENT1100791–USNMENT1100792, USNMENT1100794, USNMENT1100801–USNMENT1100802, USNMENT1100805, USNMENT1100820) ; Klipsan Beach [46.466 -124.058], 26.v.1981, C.V. Nidek (2♂ BEZA) ; Long Beach [46.353 -124.063], 1.vii.1949, C.B. Philip (9♂ CAS) , 23.viii.1972, E.I. Schlinger (1♂ BEZA) , 19.v.1977, V.F. Lee (3♂ 2♀ CAS, 4♂ 2♀ FISH) ; Ocean Park [46.490 -124.058], 9–10.viii.1950, M.T. James (1♀ RBCM) , 29.vi.1957, M.T. James (1♂ RBCM) ; Seaview [46.331 -124.066], 27.iv.1998, G.E. Hutchings (4♂ RBCM) ; Seaview, beach dunes at end of 38th Pl. , 46.331 -124.066, 30.v.1995, R.A. Cannings (1♂ CSUC, 3♂ LACM, LACM ENT 334002 – LACM ENT 334004 ) .

Taxonomic Notes. Melander’s original description noted 16 specimens as “types” which would be interpreted as syntypes in modern usage, but one male in the USNM collection has been traditionally interpreted and stored as the primary type, even receiving a red label by an unknown worker at some point. For future stability, we are hereby designating this specimen as the lectotype, and all others from this series as paralectotypes, though we have only found one specimen from the paralectotype series to date .

Etymology. No explanation given in the original description, but evidently from the Greek aktaios = of the coast or shore.

Distribution ( Fig. 39 ) Nearctic; coast of Pacific Northwest in USA: Oregon, Washington, and Canada: British Columbia (Haida Gwaii). This distribution skips over Vancouver Island and the Puget Sound area, where L. actius is apparently replaced by L. puyallupi stat. nov.; some individuals of L. puyallupi even have similar coloration (e.g., partially white mystaces). Type locality: U.S.A.: Washington: Pacific Co., Seaview.

Phylogenetic Relationships. Member of the actius group within the bivittatus section, likely as sister to L. puyallupi . Not closely related to L. arenicola despite Melander’s (1923) comment. The close genetic and morphological similarity and complimentary geographical distributions of L. actius and L. puyallupi suggest that these taxa are likely either a recent divergence with shared ancestral polymorphisms, or a case of introgression.

Natural History. Habitat: coastal sand dunes, especially on the foredune. Usually perches on bare sand adjacent to beachgrass ( Ammophila Host ) and other low, scraggly vegetation ( Fig. 6 , 3b ), occasionally found on riprap boulders. Dates collected: April 21 to September 16, most in May and June. Frequently found flying simultaneously with L. tumulicola sp. nov., though the latter species was typically encountered in the backdune field or backside of the foredune, whereas L. actius was typically on the beach side. On Haida Gwaii, flies were collected with Spiriverpa Irwin & Lyneborg (Therevidae) .

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 6–13. Representative habitats of coastal sand-perching Lasiopogon species collected for this revision. (6) Oregon: Lincoln Co., Gleneden Beach, NW tip of Salishan Spit, 17.v.2012 (L. actius on foredune, L. tumulicola sp. nov. in backdunes). (7) Washington: Grays Harbor Co., Westhaven State Park, dunes 2 mi NW of Westport, 20.vi.2013 (L. actius). (8) Oregon: Lincoln Co., Newport, Agate Beach State Park dunes, 21.vi.2013 (L. dimicki). (9) California: Humboldt Co., Clam Beach County Park ~5 mi SE of Trinidad, 15.v.2012 (L. canningsi sp. nov.). (10) California: San Mateo Co., Half Moon Bay State Beach, 5.vi.2013 (L. arenicola). (11) California: Monterey Co., Pacific Grove golf course, dunes in SW corner, 11.v.2012 (L. asilomar sp. nov.). (12) California: Santa Barbara Co., Rancho Guadalupe Dunes 1 mi S of parking lot, 9.v.2012 (L. littoris). (13) California: San Luis Obispo Co., Montaña de Oro State Park, dunes @ Sand Spit trailhead, 12.iii.2014 (L. bitumineus sp. nov., L. littoris weeks later).

FIGURES 2–5. Lasiopogon ethology. Mating pair (2) and ovipositing (3) Lasiopogon littoris at Surf Beach, Santa Barbara Co., California, U.S.A., 28.iii.2015. Photos by Alice Abela; (4) Lasiopogon drabicolum with prey (Scarabaeidae: Aphodiinae) at Santa Ana River by Mt. Rubidoux, Riverside Co., California, U.S.A., 4.iii.2013, photo by T.A. McKnight; (5) Lasiopogon littoris with prey (Acari) at Oso Flaco Lake, San Luis Obispo Co., California, U.S.A., 12.iv.2015. Photo by Aaron Schusteff.