Dasysyrphus richardi Locke & Skevington, 2013

Locke, Michelle M. & Skevington, Jeffrey H., 2013, Revision of Nearctic <i> Dasysyrphus </ i> Enderlein (Diptera: Syrphidae), Zootaxa 3660 (1), pp. 1-80 : 64-66

Dasysyrphus richardi Locke & Skevington sp. nov.

Figures: 16A–C, 20C

Diagnosis: Similar in appearance to lotus ( Figs 10A & B ), with maculae on tergites 3&4 oblique, uniform in thickness, meeting medially and not crossing the abdominal margin ( Figs 16A & C ). Dasysyrphus richardi has a dark vitta separating the gena from the face ( Figs 16A & C ) and the wing extensively bare basally ( Fig. 16B ), where as lotus is continuously light from face to gena ( Fig. 10B ) and the wing is more microtrichose ( Fig. 10C ).

Description:

Body Length: 7.2–8.0mm; Wing Length: 7.2–7.5mm

Head: Frons dark with light pollenose fascia (in female it is ½ the length between the antennae and ocelli and is continuous, sometimes notched medially) and dark pile; face light with dark vitta medially, that is <¼ the width of the face, not reaching antennal socket, face with dark pile; gena light with light pile and sometimes interspersed with dark pile, separated from face by dark vitta ( Figs 16A & C ); occiput dark, covered in light pollen, pile light with some dark pile dorsally; scape and pedicel dark, flagellomere dark, lighter at base.

Thorax: Scutum dark, may appear shiny or metallic, with two faint pollenose vittae medially, extending just past the transverse suture, pile light; scutellum light with darker lateral edges, light pile with some dark pile posteriorly; wing cells br and bm entirely bare, cell c bare at base and along Sc, r 1 bare at base and cup bare at base and along vein CuP and posterior edge, r 2+3, r 4+5, dm, cua 1 and anal lobe with bare areas at base ( Fig. 16B ); haltere light; pro- and mesofemur ⅓–½ dark basally, ½–⅔ light apically, metafemur ⅔–¾ dark basally, ¼–⅓ light apically, tibiae light, metatibia slightly darkened medially, tarsi light.

Abdomen: Maculae on tergite 2 large, oval to triangular, slightly narrowed on medial end, ⅓–<½ width of tergite, maculae on tergites 3&4 are straight and oblique, meeting medially, maculae do not reach abdominal margin and are uniform in thickness ( Figs 16A & C ); sternites light with dark fasciae of varying thickness.

Male Genitalia: Male unknown.

Intraspecific variation: Maculae on tergite 2 varying slightly in size and shape from ⅓–<½ width of tergite and oval to slightly more triangular.

Etymology: This species is named after the systematist Dr. J. Richard Vockeroth, who recognized this as a unique species and labeled the specimens as so, but did not ever describe them.

Distribution: Southwestern USA (NM) ( Fig. 20C )

Ecology: Two specimens have been collected in June in the southern Rocky Mountains.

Discussion: Known from two female specimens only. They were collected during the same collecting event in New Mexico in 1977. DNA was not extracted from these specimens as our techniques to extract from 30 year-old specimens need some improvement so that an attempt to extract DNA will have as great a chance as possible of success. With only two known specimens in existence this is crucial. Unfortunately with no male specimens, genitalia characters were not available for study. However, because richardi shares such a similar habitus to lotus it is likely that they are of close relation. An effort to find more specimens should be undertaken to locate the male of this species and to have more material made available in order to ascertain the full breadth of its molecular and morphological variation.

Type Material: “ New Mexico, Los Alamos/ Bandelier Nat. Mon./ June 1977 / W. Pippen #D-18”, “ USNM ENT 00258072 ”, “ HOLOTYPE / Dasysyrphus / richardi/ Locke &/ Skevington”; ♀, deposited in the United States National Museum of Natural History , Washington, D.C ( USNM) .

Material Examined:

Paratype: United States of America: New Mexico: Los Alamos , Bandelier Nat. Mon., [35.783115, - 106.25619], vi.1977, ♀, USNM ENT 258073 , W. Pippin ( USNM) .

Figures

FIGURE 10. Dasysyrphus lotus: A: female (CNCD 26389) dorsal habitus; B: female (CNCD 26389) lateral habitus; C: wing base (CNCD 26397); D: lateral view of male (JSS 18303) genitalia. Dorsal and lateral habitus scale bar = 1mm, genitalia and wing scale bar = 500µm.

FIGURE 16. Dasysyrphus richardi: A: female (USNM ENT 00258072) dorsal habitus; B: wing base (USNM ENT 00258072); C: female (USNM ENT 00258072) lateral habitus. Dorsal and lateral habitus scale bar = 1mm, wing scale bar = 500µm.

FIGURE 20. Dasysyrphus species range maps (symbols indicate specimen point data). A: D. amalopis (squares) and D. creper (circles); B D. intrudens complex; C: D. laticaudus (circles) and D. richardi (squares); D: D. limatus.