Lasiopogon dimicki 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 : 53-54

Lasiopogon dimicki Cole & Wilcox

Lasiopogon dimicki Cole & Wilcox, 1938: 44 .

Diagnosis. ( Fig. 33 ) A medium-sized dark brown species from the beach dunes of Oregon; macrosetae and setae of head, antenna, and thorax mostly black, a few ventrolateral setae of mystax golden-tipped; lateral setae on tergites golden, tergite 1 with 7–9 black macrosetae; scutum tomentum dark brown, with dark brown dorsocentral stripes; tergites subshining brown basally, apical 40% covered in grey tomentum as straight band in male, but extending anteriorly in female to divide brown into lateral spots. Epandrial halves moderately concave medially, with black setae; phallus dorsal carina flattened into a disc opposite gonopore. Ovipositor dark brown/black; acanthophorite spines black.

Redescription. Body length ♂ 10.7–10.9mm; ♀ 10.3–11.2mm. Head. HW ♂ 2.30–2.31mm; ♀ 2.20–2.39mm. FW ♂ 0.50–0.52mm; ♀ 0.49–0.53mm. VW ♂ 0.90mm; ♀ 0.90mm. VW/HW = ♂ 0.39; ♀ 0.38–0.41. FW/VW = ♂ 0.56–0.58; ♀ 0.54–0.59. VD/VW = ♂ 0.12–0.13; ♀ 0.11–0.13. GH/GL = ♂ 0.36–0.53; ♀ 0.40–0.52. Face browngrey, vertex brown. Ventral setae (on beard, labium, palps) white; mystax black except some golden setae ventrolaterally, all other setae black. Occipital macrosetae fine, long (0.8mm) and strongly curved anterolaterally behind vertex, lateral macrosetae short and straight. Frontal setae abundant, long (longest reach midpoint of postpedicel); orbital setae fine, long, gently curving over eye margin; ocellar setae fine, indistinct amidst other setae. Antennae. Black, with thin grey tomentum. Setae black, abundant on scape and pedicel, one seta on postpedicel. Postpedicel long, narrow, straight-edged; stylus moderately long. WPP/LPP = ♂ 0.24–0.25; ♀ 0.24–0.26. LAS/LPP ♂ 0.47–0.59; ♀ 0.57–0.65. Thorax. Prothorax brown, with yellowish-white setae; postpronotal lobes brown, the lateral angle chestnut, setae black. Scutum tomentum dark brown; dorsocentral stripes dark brown; acrostichal stripes indistinct. All setae of scutum black, major macrosetae with accompanying shorter setae; anterior dorsocentral macrosetae to 0.9mm, 6–8, posterior dorsocentrals 3–5; postalars 4; supra-alars 3; presuturals 3–4; posthumerals 2. Scutellar tomentum brown; rim inflated, leaving a semi-circular line impressed inside the dorsal edge; apical macrosetae black, abundant (9–12 on each half), mixed with other setae; setae on uppermost edge of rim half as long as macrosetae, point straight up, black. Pleural tomentum grey-brown. Katatergite macrosetae black, long, 7–10, with a few fine short yellowish-white setae; katepisternal setae fairly long, yellowish-white; anepisternal macrosetae 4–6, black (to 0.8mm), with many short black setae along dorsal margin and a few yellowish-white setae in posteroventral corner; anepimeron with 3 fine white setae. Legs. Base color black, covered in thin grey tomentum except at joints; No coxal peg. Coxae with yellowish-white setae. Macrosetae of legs black, finer setae on femur yellow-white basally with some black setae apicodorsally; fine setae on tibia white; first tarsomere on pro- and mesolegs with white setae, otherwise tarsi with black setae. Ventral setae on femur dense, longer than femur width; dorsolateral macrosetae on profemur relatively fine and indistinct basally, 4–7; on other femorae strong, short, mesofemur with 6–13, metafemur with 15–17. Protibia with ventral macrosetae 3–4 times longer than tibial width; dense patch of short yellow macrosetae on inside of protibia. Claws dark chestnut over basal 60%, black over apical half. Wings. Veins brown; membrane hyaline but pale brown when viewed obliquely. DCI = 0.32–0.43. Halter knob cream-colored, without spot, stem brown. Abdomen. Male. Tergite cuticle black; thin subshining brown tomentum on tergite bases; bands of grey tomentum cover apical 40% of each tergite, not extending anteriorly on dorsum. Tergite 1 with 7–9 lateral black macrosetae, 3–4 gold macrosetae; lateral setae on tergites yellow-white, as long as halter stem on tergites 1–3, tapering to length of scape + pedicel on posterior segments; dorsal setulae fine, brown. Sternite tomentum greybrown, setae yellow-white, long. Female. Similar to male, but basal tomentum thicker, and grey tomentum extends anteriorly along midline to separate brown tomentum into lateral spots; lateral setae on tergites 4–7 dark brown/ black and much shorter (same length as scape); dorsal setulae black, shorter. Sternite setae short. Male genitalia. Epandrium and hypandrium/gonocoxite complex cuticle shining black with thin grey tomentum; setal brush and other setae dark brown. Epandrium elongate, in lateral view the width 48% the length, widest in basal third, with straight dorsal and ventral margins; apex rounded with a shallow ventral subapical tooth. In dorsal view, medial margins of epandrium moderately curved, curvature starts about 32% from base, outer margins suddenly tapered at apex; basal sclerite short. Phallus paramere sheath dorsally 40% the length of phallus; paramere sheath without ventral ornamentation; dorsal carina divergent from aedeagal tube and protruding just farther in length, apex flattened into a disc. Ejaculatory apodeme in lateral view moderately bent dorsally in basal quarter, sometimes slightly recurved at apex, dorsal carina of moderate width. Subepandrial sclerite with triangular central unsclerotized area in basal 38% narrowing to a parallel-sided gap in central portion; spines parallel-sided, blunt, densely and evenly distributed.

Female genitalia. Undissected: Tergite and sternite 8 dark brown/black, with pale brown erect fine setae; lateral lobe with long brown macrosetae; cerci brown with pale setae; acanthophorite spines black.

Type Material. HOLOTYPE (photos examined) ♂ labelled: “[rectangular beige label] Newport / Ore. V-24 ‘31”; “[rectangular white label] J. Wilcox / Coll.”; “[rectangular beige label] Lasiopogon / dimicki/ n.sp./ Male-Type”; “[rectangular salmon label] HOLOTYPE / Lasiopogon / dimicki/ Cole & Wilcox”; “[rectangular white label] California Academy/ of Sciences, Type No. 6441”; “[rectangular white label] ALLOTYPE IS STORED/ IN THE/ GENERAL COLLECTION”. CAS.

PARATYPES (252 specimens examined): U.S.A.: OREGON: [no loc], J.E. Davis (1♂ CAS) ; Lincoln Co., Devil’s Lake [44.967 -124.015] , 17.v.1931, S.C. Jones (1♀ CAS) ; Newport [44.659 -124.058] , 8.vi.1925, E.C. Van Dyke (1♂ 2? EMEC, 1♂ RBCM), E.P. Van Duzee (1♂ 1♀ EMEC) , 10.v.1930, R.E. Dimick (4♂ 1♀ CAS) , 11.v.1930, J. Wilcox (1♀ CAS, 1♀ WSUC) , 17.v.1930, R.E. Dimick (4♂ 4♀ CAS) , 3.v.1931, I. Wilcox (4♂ 4♀ CAS, 1♂ FISH, 1♂ MCZ), J. Wilcox (18♂ 13♀ CAS [allotype included], 1♂ CNC, 1♂ EMEC, 2♂ FISH, 1♂ 1♀ USNM, USNMENT1100197 – USNMENT1100198 ) , 24.v.1931, J. Wilcox (3♂ 2♀ CAS) , 22.v.1932, J. Wilcox (16♂ 20♀ CAS, 1♂ EMEC, 3♂ FISH, 3♂ 3♀ MCZ, MCZ 19434, 1♂ 1♀ OSUC, OSUC 583662 – OSUC 583663 , 4♂ 2♀ USNM, USNMENT1100191 – USNMENT1100196 , 1♂ WSUC) , 5.vi.1932, J. Wilcox (2♂ 5♀ CAS, 1♀ USNM, USNMENT1100199 ), R.E. Dimick (4♂ 5♀ [1 pr in cop] CAS, 1♀ EMEC) , 12.v.1935, J. Wilcox (2♂ BEZA, 24♂ 24♀ 1? CAS, 1♀ CNC, 3♂ 2♀ EMEC, 1♂ 4♀ FISH, 1♂ 1♀ RBCM, 1♂ 1♀ UCRC, UCRC ENT 449917 – UCRC ENT 449918 , 2♂ 2♀ USNM, USNMENT1100200 – USNMENT1100203 ), S.E. Crumb (19♂ 5♀ CAS, 1♀ EMEC, 1♂ LACM, LACM ENT 334032 , 1♂ 1♀ USNM, USNMENT1100204 –USNMENT1100205) ; Waldport [44.433 -124.084], J.E. Davis (3♀ CAS) , 7.vi.1925, E.P. Van Duzee (1♂ 2♀ EMEC) .

Other Material Examined (28 specimens). U.S.A.: OREGON: Lincoln Co., Agate Beach [44.684 -124.068], 19.vi.1971, R.L. Westcott (1♂ 1♀ FISH, 1♂ LACM, LACM ENT 334031 ) ; Agate Beach State Park dunes [44.65795 -124.05732], 21.vi.2013, T.A. McKnight (1♂ TAM, 3♂ [3 EtOH] UMMZ) ; Newport [44.659 -124.058], 11.v.1930, J. Wilcox (1♀ EMEC) , 17.v.1930, R.E. Dimick (1♀ EMEC) , 3.v.1931, I. Wilcox (1♂ 1♀ EMEC) , J. Wilcox (2♂ 1♀ EMEC, 1♂ RBCM), 22.v.1932, J. Wilcox (1♀ RBCM) ; Newport, S side Yaquinna River mouth, dunes E of South Jetty Rd [44.601 -124.065], 8.v.1995, R.A. Cannings, H. Nadel (4♂ 4♀ RBCM, RBCM ENT 010-002849 – RBCM ENT 010-002852 ) ; Newport, South Beach State Park trailhead, 44.60146 -124.06497, 17.v.2012, T.A. McKnight (1♂ [1 EtOH] UMMZ) ; Waldport [44.433 -124.084], 7.vi.1925, E.P. VanDuzee (2♂ CAS) ; Waldport , 1 mi N, 16.v.1964, T.F. Marsh (1♂ INHS) .

Taxonomic Notes. Sometimes misidentified as L. canningsi .

Etymology. Named for R.E. Dimick, who collected the first specimens of this species seen by Cole and Wilcox ( Cole & Wilcox 1938).

Distribution ( Fig. 39 ) Nearctic; USA, Oregon coast. Type locality: U.S.A., Oregon, Lincoln Co., Newport.

Phylogenetic Relationships. Member of the actius group within the bivittatus section, likely as sister to L. willametti .

Natural History. Habitat: beach dunes. Perches on bare sand adjacent to low, scraggly vegetation, such as Elymus L., Lupinus L., Fragaria L. ( Fig. 8 ). Dates collected: 3 May to 21 June.

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).