Lasiopogon martinensis 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 : 65-66

Lasiopogon martinensis Cole & Wilcox

Lasiopogon martinensis Cole & Wilcox, 1938: 54 .

Lasiopogon martinorum Cole & Wilcox ; Cannings 2002: 62. Unnecessary emendation.

Diagnosis. ( Fig. 36 ) A medium-large grey species from the Columbia River basin; mystax and most setae of head, thorax, and abdomen black; antennal postpedicel long, white setae on scape; dorsocentral macrosetae fine, other scutal macrosetae strong, fine setae of scutum half as long as dorsocentrals; apical scutellar macrosetae sparse. Thoracic tomentum grey, dorsocentral stripes brown, acrostichal stripes faint dark brown; abdominal tergites basally with subshining brownish grey tomentum; thick grey tomentum over apical 50% of each tergite and along lateral margins. Lateral macrosetae on abdomen long, dense, white; 5–6 black macrosetae laterally on tergite 1. Epandrium reddish brown, covered in thin grey tomentum and black setae; stout, with width 61% of length, apex broadly rounded; medial margin gently concave in dorsal view. Ovipositor dark brown/black; acanthophorite spines black.

Redescription. Body length ♂ 10.4–11.5mm; ♀ 11.6–13.7mm. Head. HW ♂ 2.18–2.47mm; ♀ 2.50–2.73mm. FW ♂ 0.48–0.53mm; ♀ 0.58–0.59mm. VW ♂ 0.87–1.00mm; ♀ 1.09–1.13mm. VW/HW = ♂ 0.40–0.42; ♀ 0.41– 0.44. FW/VW = ♂ 0.49–0.55; ♀ 0.51–0.54. VD/VW = ♂ 0.13–0.22; ♀ 0.15–0.19. GH/GL = ♂ 0.36–0.53; ♀ 0.35–0.42. Tomentum of face silver/white; vertex and occiput thin, brown-grey. Beard, and labial setae white; mystax and other setae brown/black. Occipital macrosetae strong, relatively sparse and short (to 0.5mm), somewhat curved apically. Frontal and orbital setae sparse, fine, long (most as long as scape + pedicel). Antennae. Brown, base of postpedicel and apex of stylus chestnut. Setae on scape white, pedicel with brown macrosetae and finer white setae; 0–1 brown setae on postpedicel. Postpedicel long, straight, slightly constricted past midpoint; stylus tapered. WPP/LPP = ♂ 0.23–0.29; ♀ 0.25–0.30. LAS/LPP ♂ 0.50–0.67; ♀ 0.47–0.53. Thorax. Prothorax grey, setae white; postpronotal lobes grey to brownish grey, lateral angle ferruginous, setae mostly black, a few white dorsally. Scutum tomentum grey, browner around the perimeter; dorsocentral stripes brown, acrostichal stripes dark grey. Macrosetae and setae of scutum black. Dorsocentral macrosetae weak anteriorly, 4–5 in number and only twice as long (to 0.8mm) as surrounding fine seta; posterior dorsocentral macrosetae more prominent, 4–5 in number. Other macrosetae strong; postalars 3, with 7–8 shorter setae; supra-alars 3; presuturals 2; sometimes a weak posthumeral. Scutellar tomentum grey, ranging from silvery to brownish; rim strongly inflated, leaving a semi-circular line impressed inside the dorsal edge; apical macrosetae black, 3–4 on each side angled upward, with a similar number of fine black setae; disc of scutellum with short, fine white setae. Pleural tomentum grey. Katatergite macrosetae 8–10, long, mostly black but a few (1–3) white; several fine white setae half the length of the primary setae; katepisternal setae abundant, rather long, white; anepisternal setae 5, brown, moderately strong (to 0.7mm) and mixed with other setae, a patch of short white setulae on dorsal margin of sclerite; anepimeron without setae. Legs. Base color dark brown, paler on tarsi, ferruginous at joints of coxa/femur and femur/tibiae; tomentum of coxae grey, tomentum on rest of legs sparse grey. No coxal peg. Macrosetae on legs black, finer setae on femur white, on tibiae white above, brown below, on tarsi black. Ventral setae on femur shorter than femur width; dorsolateral macrosetae strong, 5–6 on profemur, mesofemur 5–6, metafemur 10–12. Protibia with ventral macrosetae 1.5–2.5 times longer than tibial width; apicomedial patch of short dense setae on protibia faint yellow, on metafemur brown. Claws dark brown over basal 60%, apically black. Wings. Veins brown; membrane transparent, brownish when viewed obliquely. DCI = 0.29–0.49, most between 0.30–0.36. Halter orange-yellow, knob without spot. Abdomen. Cuticle black; subshining faintly brownish grey tomentum at tergite bases, thick grey tomentum over apical 50% of each tergite, lateral margins broadly grey, overall appearance grey. Lateral setae on all tergites long, white (black on tergites 4–7 in female); tergite 1 with 5–6 long black macrosetae; dorsal setulae white (black in female). Sternite tomentum grey, setae white. Male genitalia. Epandrium and hypandrium/gonocoxite complex cuticle dark brown/chestnut; covered in thin grey tomentum; setae dark brown, long and prominent; setal brush dark brown. Epandrium stout, in lateral view the width about 61% the length, widest medially, apex broadly rounded. In dorsal view, medial margins of epandrium shallowly concave, close set; basal sclerite prominent. Phallus paramere sheath dorsally 46% the length of phallus; paramere sheath with ventrolateral carina, ventral lip strongly projecting, no ventral flange; apex rounded; dorsal carina broad, coming to point even with aedeagal tube that leaves a narrow, shallow gap between apex and gonopore. Ejaculatory apodeme in lateral view bent dorsally in basal quarter, with broad dorsal carina. Subepandrial sclerite with triangular central unsclerotized area in basal 38% narrowing to a parallel sided gap in central portion; spines parallel-sided, blunt, densely distributed except basolaterally.

Female genitalia. Undissected: Setae white, abundant, erect. Tergite 8 shining brown/black with reddish brown apical band; sternite 8 shining reddish brown, dark brown near apical lobes; hypogynial valves black; lateral lobes with short pale setae. Cerci brown with pale setae; acanthophorite spines black.

Type Material. HOLOTYPE ♂ (photos examined) labelled: “[rectangular white label] Pasco, Wn./ IV.17.1934”; “[rectangular yellow label] Chas. H. Martin / Col.”; “[rectangular salmon label] HOLOTYPE / Lasiopogon / martinensis/ Cole & Wilcox”; “[rectangular white label] California Academy / of Sciences / Type No. 6505”. CAS . PARATYPES (3 examined): U.S.A.: WASHINGTON: Franklin Co., Pasco [46.206 -119.037], 17.iv.1934, C.H. Martin (1♀ EMEC, 1♂ ESUW), D. Martin (1♂ EMEC) .

Other Material Examined (14 specimens). U.S.A.: IDAHO: Canyon Co., Caldwell [43.679 -116.695], 21.v.1970, J.D. Marshall (1♀ ESUW, 1♂ RBCM) ; Parma [43.802 -117.001], 13.v.1933, F.H. Shirck (1♀ CAS) , 13.v.1934, D. Martin (1♂ RBCM) , 19.v.1934, C.H. Martin (1♀ RBCM) ; WASHINGTON: Benton Co., Paterson [45.934 -119.598], 26.iv.1936 (2♂ 2♀ USNM, USNMENT1100410 – USNMENT1100411 , USNMENT1100413 – USNMENT1100414 ) ; Richland, Yakima River [46.276 -119.317], 2.v.1946, C.H. Martin (1♂ FISH, 2♂ FSCA) ; Franklin Co., Pasco [46.206 -119.037], 17.iv.1934, D. Martin (1♀ FSCA) ; Whitman Co., Wawawai [46.581 - 117.297], 15.v.1909, W.M. Mann (1♂ RBCM) .

Taxonomic Notes. Although the ideal suffix given the stated etymology would be “–orum” instead of “–ensis”, an emendation used in Cannings (2002), our understanding is that this incorrect Latinization is not correctable in accordance with ICZN Code article 32.5.1.

Some figures and characters coded as L. martinorum in Cannings (2002) actually correspond to L. ripicola ; these species have frequently been mistaken for each other.

Etymology. Named in honor of Charles and Dorothy Martin, whose collecting provided much material for work on robber flies ( Cole & Wilcox 1938), including the original specimens of this species.

Distribution ( Fig. 42 ) Nearctic; USA, Columbia River basin in eastern Washington and western Idaho. Type locality: U.S.A., Washington, Pasco. The habitat of the type locality has likely been significantly altered as a result of the installation of dams flooding and slowing the riparian zone.

Phylogenetic Relationships. Usable DNA could not be amplified from any specimens available to us, but morphology strongly suggests that this species is a member of the opaculus section, tetragrammus species group, probably closely related to L. lavignei Cannings 2002 . Specimens of L. ripicola were mistakenly used to code L. martinensis in the phylogenetic analysis of Cannings (2002); L. martinensis does not belong in the bivittatus section.

Natural History. Habitat: unknown, probably riparian sandbanks in grassland based on the historical localities and ethology of closely related species. This species has not been collected in decades despite many attempts by the authors to find modern populations in eastern Washington and western Idaho. Given this failure and the localities and dates when specimens were last collected, it is possible that this species has been extirpated due to anthropogenic ecological changes in riparian habitats of the Columbia River Basin from the installation of dams. The banks of the Columbia and Snake rivers are now generally so flooded and slow that they rarely form the sandy and rocky habitats typical for Lasiopogon species, though it is possible that isolated populations may persist in relictual locations such as the Hanford Reach.

Figures

FIGURE 36. 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. (36) L. karli sp. nov., L. martinensis.

FIGURES 41–42. Distribution maps of georeferenced records for Lasiopogon species revised in this publication, part 2 of 2. Each map corresponds to one page of the morphology tabular key.