Culicoides cavaticus Wirth and Jones

Phillips, Robert A., 2022, Culicoides Latreille and Leptoconops Skuse biting midges of the southwestern United States with emphasis on the Canyonlands of southeastern Utah (Diptera: Ceratopogonidae), Insecta Mundi 2022 (907), pp. 1-214 : 106-107

Culicoides cavaticus Wirth and Jones

( Fig. 81–83 , 136, 137, 228, 263)

Culicoides cavaticus Wirth and Jones, 1956: 166 (key; female, male; fig. female wing, mesonotum, palpus, spermathecae, male genitalia; California). Wirth et al. 1985: 22 (numerical characters; fig. female wing). Murphree and Mullen 1991: 338 (key; larva; numerical characters; fig. head, epipharynx, hypostoma, mandible, caudal segment).

Culicoides unicolor (Coquillett) , misidentified: Wirth 1952a: 185, 253 (in part as “well-marked treehole phase”; key; female; male genitalia; pupa; larva; fig. female wing, palpus, male genitalia, pupal respiratory horn, caudal segment, larval head, caudal segment; larval habitat). Fox 1955: 258 (in part; keys).

Diagnosis. ( Tables 14, 15) Wing pattern distinct; r 2 dark; isolated pale spots straddling midportions of M 1 and M 2; distal pale spots in r 3, m 1, m 2; distinct to barely visible pale band or patch along posteromedian margin of anal cell; flagellomeres 9–10 normal, each larger than 8; SCo pattern 1–13; palpus with broad shallow sensory pit almost as wide as segment; labrum without apical median projection; scutellum with 28–30 setae on female; fore and hind tarsomeres without apical spines; spermathecae unequal by ~1.1, sclerotized necks absent; sclerotized ring on spermathecal duct; male tergite 9 posterior margin concave, with distinct apicolateral processes extending beyond medial portion; sternite 9 caudomedian excavation moderate, about evenly curved; ventral apodeme of gonocoxite broad with two short widely divergent processes, stoutly footlike; aedeagus Y-shaped, basal arms with basal ends sharply bent laterally, arms without submedian fingerlike lobes, arms posteromedially connected only by unsclerotized or barely sclerotized membrane, median process simple, aedeagal ratio ~0.7; parameres separate with basal heads clublike, with fringe of spines on apical third, without submedian lobe.

Distribution. Oregon, California, Utah (Grand County, new state record), Arizona. A male was collected using a CDC incandescent light trap on 5 July 2001 at 38.54491°N 109.51000°W and 1331 m elevation, a riparian habitat with abundant cottonwoods ( Populus fremontii ) and oaks ( Quercus sp. ).

Larval ecology. Culicoides cavaticus have been collected and reared from treeholes in black walnut, walnut, sycamore, and cottonwood ( Wirth and Jones 1956) and collected from emergence traps over treeholes in Pacific madrone ( Arbutus menziesii Pursh , Ericaceae ), and oaks ( Fagaceae : Quercus kelloggii , Q. lobata Nee , and Q. wislizenii ) with strong emergence peaks in April and July in Northern California ( Woodward et al. 1988). Clark and Fukuda (1967) collected C. cavaticus larvae and Aedes sierrensis (Ludlow) (Culicidae) larvae from an oak treehole and observed some of the C. cavaticus killing and feeding on the mosquitos, indicating a predatory role on macroinvertebrates in its treehole habitat.

Adult behavior. Weinmann et al. (1979) collected blood-engorged C. cavaticus from California quail ( Callipepla californica )-baited traps; however, they found no C. cavaticus infected with quail heartworm ( Splendidofilaria californiensis ) or other evidence it can transmit the parasite.

Figures

Figures 81–87. Male genitalia of Culicoides Piliferus group, ventral view. 81) C. cavaticus, focused on aedeagus. 82) C. cavaticus, focused on aedeagus arm base (Aab), basal head of paramere (Ph), ventral apodeme of gonocoxite (Gcva) (paratype, Sacramento County, CA [FSCA]). 83) C. cavaticus (Grand County, UT). 84) C. doeringae, focused on aedeagus. 85) C. doeringae, focused on basal head of paramere (Ph), ventral apodeme of gonocoxite (Gcva). 86, 87) C. Piliferus group species A variations.