Lasiopogon asilomar McKnight, 2020

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 : 41-43

Lasiopogon asilomar McKnight sp. nov.

urn:lsid:zoobank.org:act:CA4A0D31-11EC-46C0-B02B-A455A70F27C8

Diagnosis. ( Fig. 31 ) A medium-sized species from central California coastal dunes; all macrosetae and setae white/ gold; thoracic tomentum thin, brown cuticle shining through in dorsocentral stripes; abdominal tergites with basal brown tomentum very thin, male with tergite bases broadly subshining dark, grey tomentum in straight bands over apical 30% of each tergite; female with grey tomentum faintly reaching along midline to create basal spots of subshining brown/black. Epandrium strongly concave medially, curvature starting about 25% from base; apical 30% bare of tomentum, with slightly toothed square ventral edge. Ovipositor dark brown/black, acanthophorite spines pale to dark brown.

Description. Body length ♂ 8.7–11.9mm; ♀ 9.9–11.5mm. Head. HW ♂ 1.95–2.54mm; ♀ 2.16–2.48mm. FW ♂ 0.40–0.57mm; ♀ 0.52–0.59mm. VW ♂ 0.80–1.14mm; ♀ 0.93–1.07mm. VW/HW = ♂ 0.41–0.46; ♀ 0.42–0.46. FW/VW = ♂ 0.49–0.50; ♀ 0.53–0.56. VD/VW = ♂ 0.06–0.11; ♀ 0.10–0.11. GH/GL = ♂ 0.34–0.60; ♀ 0.38–0.39. Face and vertex with tan-grey tomentum. Beard, labial, frontal and occipital setae all white; mystax dirty white. Occipital macrosetae long and steadily curved through 90°, those behind the dorsomedial angle of the eye to 0.9mm long and most curved; lateral and ventral macrosetae shorter, straighter. Frontal setae fine and short; orbital setae longer, extend over the eye for half their length. Antennae. Brown to black. Setae dirty white; no setae on postpedicel. Postpedicel long and rectangular, with straight dorsal and ventral margins; stylus short and tapered. WPP/LPP = ♂ 0.27–0.34; ♀ 0.28–0.36. LAS/LPP ♂ 0.58–0.79; ♀ 0.61–0.78. Thorax. Prothorax brown/grey, setae dirty white; postpronotal lobes brown, the lateral angle ferruginous, setae white. Scutum tomentum brownish-grey/grey. Dorsocentral stripes thin dark brown; acrostichal stripes greyish brown. Notal and acrostichal setae white, long; anterior dorsocentral macrosetae 4–8, white (to 1.3 mm), relatively fine and mixed with finer setae; 5–6 posteriors. Other macrosetae white; postalars 2–4, with several additional setae; supra-alars 3–4 with 1 or 2 additional setae; presuturals 3; posthumerals 1–2. Scutellar tomentum subshining brownish grey; rim strongly inflated, leaving a semicircular line impressed inside the dorsal edge; apical macrosetae whitish, abundant (usually 9–11+ on each side) and mixed with many other long setae. Pleural tomentum grey, brownish on the lower anepisternum. Katatergite macrosetae dirty white, 9–11 with a few weaker setae; katepisternal setae sparse, moderately long, white; anepisternal setae 3–8, usually moderately strong (to 0.9mm) and mixed with other setae, a patch of short white setae on dorsal margin of sclerite; anepimeron with 1–2 fine setae, white. Legs. Base color usually dark brown to black, dark reddish at joints of coxa/femur, femur/tibiae, and tarsal bases; tomentum of coxae and rest of legs grey, sparse. No coxal peg. Macrosetae on legs dirty white, finer setae white. Ventral setae on femur dense, longer than femur width; dorsolateral macrosetae strong, mixed with many finer setae, 3–7 on profemur; longer on mesofemur (5–6) and metafemur (10–14). Protibia with longest macrosetae about 3 times longer than tibial width. Claws chestnut over basal 50–60%, apically black. Wings. Veins dark brown; membrane transparent, milky white when viewed obliquely. DCI = 0.31–0.44. Halter yellow/orange, with no spot. Abdomen. Male. Cuticle dark brown/black basally; tergite bases subshining dark brown, bands of grey/grey-gold tomentum cover apical 30% of each tergite (tergite 1 fully covered in grey) and extending anteriorly 50% along lateral margins, but only faintly apparent along midline (overall appearance is straight band). All setae yellow/white; tergite 1 with abundant (12+) lateral macrosetae; lateral setae on tergites 2–3 longer than basitarsus and erect, on tergites 4–7 as long as F1. Sternite tomentum grey, setae white. Female. Tomentum along midline of tergites lighter, creating the illusion of diffuse basal subshining brown spots. Setae on sides of tergites 4–7 shorter than in male. Male genitalia. Epandrium and hypandrium/gonocoxite complex cuticle dark brown/chestnut; epandrium polished over apical 30%, otherwise covered in thin grey tomentum; covered in long white setae, setal brush yellowish white. Epandrium elongate, in lateral view the width about 45% the length, widest in basal third, dorsally and ventrally sinuate; apex right-angled ventrally, straight-edged apically, and rounded dorsally. In dorsal view, medial margins of epandrium strongly curved, curvature starting 25% from the base of the epandrium; basal sclerite prominent. Phallus paramere sheath dorsally 60% the length of phallus; paramere sheath with small ventral flange near base; dorsal carina a narrow wave-like fin with straight apex not projecting apically and ending well short of the gonopore. Ejaculatory apodeme in lateral view moderately bent dorsally in basal quarter, slightly recurved at apex; dorsal carina moderately wide. Subepandrial sclerite with triangular central unsclerotized area in basal 70%; spines blunt, sparsely distributed.

Female genitalia. Undissected: Setae white, abundant, erect. Tergite 8 black with posterior margin paler; sternite 8 black, with a lighter spot medially; lateral lobe setae long; hypogynial valves with long fine setae, concentrated basally and apically; cerci black with pale setae; acanthophorite spines pale to dark brown/black.

Variation. Most individuals have white or dirty white setae and macrosetae, but a few specimens are completely clothed in golden setae, otherwise indistinguishable in morphology or genetics. Similar golden morphs have been observed in several other Lasiopogon species ( L. canningsi , L. monticola , L. zonatus ).

Type Material. HOLOTYPE ♂ labelled: “[rectangular white label] ASILOMAR/ 3/9/45 CAL/ ALMELANDER”; “[rectangular white and green label] ALMelander/ Collection/ 1961”; “[rectangular white label] Lasiopogon / arenicola/ O.S. ‘65/ det. J. Wilcox ”; “[rectangular white label] USNMENT01100340”. Our holotype label “HOLOTYPE/ Lasiopogon ♂ / asilomar McKnight / des. T.A. McKnight 2017 [red, black-bordered label]” has been attached to this specimen. Deposited at USNM.

PARATYPES (200 specimens designated): U.S.A.: CALIFORNIA: Monterey Co., Asilomar [36.626 -121.939], 1.ix.1945, A.L. Melander (2♂ 1♀ USNM, USNMENT1100327 , USNMENT1100335 –USMENT1100336), 2.ix.1945, A.L. Melander (2♂ 5♀ USNM, USNMENT1100328 – USNMENT1100334 ), 3.ix.1945, A.L. Melander (2♂ 2♀ RBCM, 13♂ 6♀ USNM, USNMENT1100337 – USNMENT1100339 , USNMENT1100341 – USNMENT1100356 ), 28.ix.1946, A.L. Melander (2♂ UCRC, UCRC ENT 449898 , 20♂ 14♀ 2? USNM, USNMENT1100293–USNMENT1100303, USNMENT1100315–USNMENT1100321), 29.ix.1946, A.L. Melander (2♂ 2♀ UCRC, UCRC ENT 449897 , UCRC ENT 449900 , 10♂ 12♀ USNM, USNMENT1100304 – USNMENT1100314 , USNMENT1100325 ), 2.x.1946, A.L. Melander (2♀ UCRC, UCRC ENT 449899 , 1♂ 2♀ USNM, USNMENT1100322–USNMENT1100323), 3.x.1946, A.L. Melander (1♀ USNM, USNMENT1100324 ), 26.iv.1947, George Geiwitz (2♂ CAS) , 11.vii.1957, A.L. Melander (1♂ USNM, USNMENT1100326 ), 23.v.1959, J.R. Powers (1♂ 1♀ UYWO) ; Giberson Beach [36.836 -121.802], 17.v.1959, D. Jamieson (1♂ 1♀ BEZA) ; Monterey [36.606 -121.864], 25.ix.1934, A.L. Melander (1♂ 1♀ USNM, USNMENT1100291 – USNMENT1100292 ), 24.ix.1938, M. Cazier (2♀ CAS, 2♂ 1♀ CSUC), 20.v.1956, M. Wasbaner (1♂ 1♀ CAS) ; Moss Landing [36.803 -121.788], 1.iv.1961, Ed Ball (1♂ 1♀ FSCA) , 27.v.1969, M.E. Irwin, F.G. Andrews (8♂ 3♀ UCRC, UCRC ENT 449902 – UCRC ENT 449912 ) ; Pacific Grove [36.633 -121.936], v.1906, J.M. Aldrich (1♂ 1♀ USNM, USNMENT1100279 –USNMENT1100280), 7.v.1906, J.M. Aldrich (2♂ 2♀ USNM, USNMENT1100281 – USNMENT1100284 ), 9.v.1906, J.M. Aldrich (3♂ USNM, USNMENT1100286 – USNMENT1100288 ), 10.v.1906, J.M. Aldrich (1♂ USNM, USNMENT1100285), 27.viii.1957, R.M. Bohart (4♂ 1♀ FSCA, 1♂ RBCM), 17.iv.1965, B.A. McKinley (1♀ CAS) ; Pacific Grove, dunes in golf course by Sunset Dr , 36.6330 -121.9362, 11.v.2012, T.A. McKnight (2♂ 2♀ TAM, 3♂ 4♀ [7 EtOH] UMMZ) ; Pacific Grove, Point Pinos [36.634 -121.936], 24.v.1952, P.H. Arnaud (1♂ 2♀ CAS, 1♀ EMEC) ; Pajaro River mouth [36.851 -121.809], 12.v.1975, D.W. Moss (1♀ BPBM) , 23.v.1976, D.W. Moss (4♂ 1♀ BEZA) ; Seaside [36.634 -121.836], 16.vii.1967, M.E. Irwin (1♀ UCRC, UCRC ENT 449913 ), 5.ix.1970 (1♀ BEZA) ; Riverside Co., the Gavilan , 17.v.1951, E.I. Schlinger (1♂ 1♀ FSCA) ; San Luis Obispo Co., Oceano [35.095 -120.621], 24.iv.1951, R.M. Bohart (1♂ CNC) ; Oso Flaco Lake [35.032 -120.627], 13.vii.1959, I.L. Bath (1♂ UCRC, UCRC ENT 449896 ) ; Paso Robles, Salinas River E side [35.642 -120.683], 17.iv.1990, D.W. Webb, M.E. Irwin (1♀ INHS) ; Pismo Beach [35.087 -120.626], 24.iii.1940, R.G. Dahl (1♂ RBCM) , 13.v.1956, J. Wilcox (2♂ 1♀ CAS, 1♂ USNM, USNMENT1100289 ), 5.x.1964, W. Bish (1♂ LACM, LACM ENT 334125 ) ; Santa Cruz Co., Santa Cruz [36.964 -122.009], 2.v. (2♀ CAS, 2♂ 6♀ FSCA), 29.v. (2♂ CAS, 1♂ 4♀ FSCA) .

Taxonomic Notes. In previous publications, this species was subsumed into the species concept of L. arenicola , a closely related species found allopatrically to the north on the San Francisco Peninsula. These species can be readily distinguished by comparing the tomentum patterns of the abdominal tergites.

Etymology. Asilomar is a local name for the beach dune complex at Pacific Grove, coined in 1913 by Helen Salisbury from the Spanish “asilo” (haven, refuge) and “mar” (sea). Used here as a noun in apposition to maintain the phonetic similarity to “ Asilidae ” and commemorate their local habitat.

Distribution ( Fig. 37 ) Nearctic; USA, California; beach dunes along the central California coast between Santa Cruz and Pismo, though only infrequently collected in San Luis Obispo County. Two specimens with locality labels saying “The Gavilan, Cal/Riverside Co” collected 17.v.1951 by E.I. Schlinger (FSCA) are anomalous or probably mislabeled. Type locality: U.S.A.: California: Monterey Co., Asilomar.

Phylogenetic Relationships. Member of the bivittatus section, drabicolum group; likely the sister species to L. arenicola .

Natural History. Habitat: coastal sand dunes. Perches on bare sand adjacent to scraggly vegetation ( Fig. 11 ). Dates collected: 1 April to 5 October, but clustered around two separate phenological peaks, one in late May, one in September, with records from both peaks from both the north and south of the range. The early peak is coincident with the emergence window for L. littoris , which is sympatric over part of the southern range and numerically dominant there. The late peak is unique in Lasiopogon —we know of no other species collected in late September or October. Two females and one male with prey: 2 Coleopa Meigen ( Diptera : Coleopidae), 1 Anthomyiidae (Diptera) .

Figures

FIGURE 31. 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. (31) L. albidus, L. arenicola, L. asilomar sp. 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).