Lasiopogon apoecus 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 : 37-39

Lasiopogon apoecus McKnight sp. nov.

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Diagnosis. ( Fig. 34 ) A medium-sized dark species from mountain meadows of southern California and Baja California; with mystax black, thoracic tomentum grey to golden brown with distinct dorsocentral stripes, thoracic setae black, legs black; tergite tomentum in male starts out as mostly separate spots of basal brown that fuse into a single band on later segments, female with spots only. Epandrial halves strongly curved over medial margins, phallus dorsal carina comes to a hemispherical apex parallel to gonopore; ovipositor dark brown, acanthophorite spines black.

Description. Body length ♂ 9.11–9.22mm; ♀ 9.63–10.28mm. Head. HW ♂ 2.05–2.06mm; ♀ 2.16–2.33mm. FW ♂ 0.45–0.46mm; ♀ 0.49–0.54mm. VW ♂ 0.84–0.85mm; ♀ 0.88–0.99mm. VW/HW = ♂ 0.41; ♀ 0.41–0.42. FW/VW = ♂ 0.53–0.55; ♀ 0.55–0.56. VD/VW = ♂ 0.13–0.14; ♀ 0.12–0.16. GH/GL = ♂ 0.39–0.43; ♀ 0.43–0.51. Face and vertex with grey tomentum. Ventral setae (on beard, labium, palps) white; mystax and all dorsal setae black. Occipital macrosetae fine, longest (to 0.7mm) and most strongly curved forward posterior of frons, lateral macrosetae slightly hooked. Frontal setae average length, erect, reach basal quarter of postpedicel; orbital setae fine, average length, slightly curved over eye margin; ocellar setae slightly longer than surrounding setae. Antennae. Black, with thin grey tomentum. Setae black, 0–1 short setae on postpedicel. Postpedicel widest at midpoint, tapering to apex; stylus moderately short. WPP/LPP = ♂ 0.30–0.33; ♀ 0.25–0.26. LAS/LPP ♂ 0.57–0.63; ♀ 0.43–0.48.

Thorax. Prothorax brown-grey, with white setae; postpronotal lobes grey, the lateral angle dark chestnut, setae white except a few black laterally. Scutum tomentum grey, slightly brownish on lateral margin; dorsocentral stripes brown, acrostichal stripes usually faint or absent (sometimes brown). All macrosetae and setae of scutum black; short notal setae very fine; dorsocentral macrosetae not particularly distinct; anterior dorsocentrals 3–5, to 1.0mm; posteriors 3–4; postalars 3, with several shorter setae; supra-alars 2–3, with a few shorter setae; presuturals 2–3; posthumerals 0–1. Scutellar tomentum grey; apical macrosetae black, long, 8–9 on each side, with several other long setae; a few sparse setae on uppermost edge of rim less than half as long as apical macrosetae. Pleural tomentum yellow-grey. Katatergite macrosetae black, 6–8, with 0–2 long and a few short white setae; katepisternal setae of moderate length, white; anepisternum with 4–6 fine setae to 0.7mm and several shorter setae along dorsal margin; anepimeron with 0–3 short white setae. Legs. Base color dark brown/black; covered in thin grey tomentum except at both femur joints. No coxal peg. Coxae with all white setae. Macrosetae of legs black except 1–2 white at base of femur; finer setae black except white setae ventrolaterally on femur. Ventral setae on femur long and abundant; dorsolateral macrosetae indistinct, profemur with 8–13 macrosetae; mesofemur 5–6; metafemur 7–10. Protibia with ventral macrosetae very fine, 3 times as long as tibial width. Dense patch of short yellow setae along inside apical half of protibia. Claws chestnut over basal 60%, black apically. Wings. Veins light brown; membrane hyaline but brown when viewed obliquely. DCI = 0.35–0.48. Halter knob cream, without spot, stem slightly darker. Abdomen. Male. Tergite cuticle dark brown/black. Thin brown tomentum faintly on tergite bases, grey tomentum in bands that cover apical 50–60% of each tergite (tergite 1 completely covered) and sometimes faintly extend anteriorly along the midline leaving pattern indistinct. Tergite 1 laterally with 4–5 black macrosetae, 1–3 white macrosetae. Lateral setae on tergites white, on tergites 1–3 as long as scape + pedicel, on tergites 4–7 a little shorter; dorsal setulae short, brown. Sternite tomentum grey, setae white. Female. Apical grey tomentum does extend anteriorly along the midline, splitting basal brown into two lateral spots. Apex of sternite 7 with several strong erect black setae. Male genitalia. Epandrium and hypandrium/gonocoxite complex cuticle dark brown/black, covered in thin grey/brown tomentum except medially on hypandrium, where reddish-brown cuticle is bare; setae long and black, setal brush dark brown. Epandrium elongate, in lateral view the width 43% the width, widest in basal third, slightly sinuate along ventral margin, gently curved to straight along dorsal margin; apex rounded with ventral subapical tooth. In dorsal view, medial margins of epandrium moderately curved, curvature starts about 35% from base; basal sclerite prominent. Phallus paramere sheath dorsally 48% the length of phallus; paramere sheath with long, buttress-like ventral flange along basal half; dorsal carina extending parallel to gonopore, with rounded apex slightly compressed dorsoventrally. Ejaculatory apodeme in lateral view strongly bent dorsally in basal quarter, dorsal carina narrow. Subepandrial sclerite with triangular central unsclerotized area in basal 45%; spines parallel-sided, blunt, densely and evenly distributed.

Female genitalia. Undissected: Cuticle dark brown except reddish at base of hypogynial valves. All setae dark brown/black except short white setae on cerci; weak but erect setae on tergite and sternite 8; lateral lobes with short black macrosetae; acanthophorite spines black.

Variation. Specimens from Riverside County, California are more richly brown-colored, with more distinct acrostichal stripes and less apical grey tomentum on tergites.

Type Material. HOLOTYPE ♂ labelled: “[rectangular white label] Sierra San Pedro Martir / LaGrulla, 6500’/ Baja Calif., MEX. V-29-58”; “[rectangular white label] J. Powell / Collector ”; “[rectangular white and pink label] UCB”; “[rectangular white label] FISH ”; “[rectangular white label] RBCM-46 ”. Our holotype label “ HOLOTYPE / Lasiopogon ♂ / apoecus McKnight / des. T.A. McKnight 2017 [red, black-bordered label]” has been attached to this specimen. Deposited at USNM.

PARATYPES (16 specimens designated): MEXICO: BAJA CALIFORNIA NORTE: Sierra San Pedro Martir , 4 mi S Encinas, 6000’ [30.793 -115.598], 2.vi.1958, J. Powell (1♂ FISH) ; Sierra San Pedro Martir, La Grulla , 6500’ [30.892 -115.464], 29.v.1958, J. Powell (2♂ 2♀ FISH, 1♂ RBCM, 1♂ 1♀ TAM), 30.v.1958, J. Powell (3♀ FISH, 1♀ RBCM) .

U.S.A.: CALIFORNIA: Riverside Co., Hurkey Creek [33.684 -116.676], 23.iv.1937, A.J. Basinger (3♂ CAS, 1♂ RBCM) .

Taxonomic Notes. This species was included in Cannings (2002) as “L. biv-1.”

Etymology. From the Greek άποικος, apoikos, meaning colonist or resident in a settlement far from home; noun in apposition; befitting because this species ranges farther south than all other Lasiopogon known from this hemisphere.

Distribution ( Fig. 40 ) Nearctic; mountains of northern Baja California Norte and southern California. Type locality: Mexico: Baja California Norte: Sierra San Pedro Martir, La Grulla.

Phylogenetic Relationships. We did not recover usable DNA from any of the Mexican or Hurkey Creek (California) samples we tested; however, based on genitalia morphology we believe that this species is likely a member of the bivittatus section, related to L. condylophorus sp. nov. and L. gabrieli , especially the former.

Natural History. Habitat: unknown, but the original collecting localities in Baja California were described as a “small lush meadow among oaks […] cool clear stream […] downstream lupine was in bloom in abundance […] steep walled canyon of heavy vegetation […] beautiful meadow which stretches amongst conifer [Ponderosa pine] forest […] in a sinuate expanse of green grass” ( Patterson & Powell 1959: 232). Dates collected: April 23 to June 2.

Figures

FIGURE 34. 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. (34) L. apoecus sp. nov., L. condylophorus sp. nov., L. gabrieli, L. wilcoxi sp. nov., L. zonatus.

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.