A 10 mm Tabanus abdominalis Fabricius A dorsal

A 10 mm Tabanus abdominalis Fabricius: A, dorsal; B, lateral; C, ventral. B 21. 2 mm C

A Tabanus abdominalis Fabricius: A, dorsal; B, lateral; C, oblique; D, ventral. C D B

Tabanis abdominalis Fabricius collected Jeff’s Bike Shop, Cabell Co. , WV on 17 Aug 2015. En face view (A); proboscis enlarged (B). Legend: a, antenna, c, compound eye; cl, clypeus; pl, palp; pr, proboscis; t, theca. Note; palps overly proboscis at rest but here they have been pushed aside to expose the labial gutter. Tip of labrum indicated by arrow in B. A B cl c pr t a pl 3. 1 mm

fc v ar Labrum of Tabanus abdominalis. Dashed arrows mark junction of vestibule (v) with food canal (fc). Note pair of hair-bearing trichites (mechanoreceptors) at base of vestibule and bullet-shaped trichites (chemoreceptors) in yellow oval. The chemoreceptors seem an anomaly because they are on the same side of the vestibule wall with none on the opposing wall. Air artifact in tissues indicated by ar.

Labrum of Tabanus abdominalis. Note two chemoreceptors (purple ovals) that are larger in diameter, and with “bullet-like” trichites projecting from them, in opposing walls of the food canal. All other trichites in view are mechanoreceptors.

Labrum of Tabanus abdominalis. Note two chemoreceptors (purple ovals) that are larger in diameter, and with “bullet-like” trichites projecting from them, in opposing walls of the food canal. All other trichites in view are mechanoreceptors.

T. atratus

Tabanus abdominalis chemoreceptors in food canal. Spmn. # ? Spmn. #1

T. abdominalis T. atratus

T. abdominalis spmn #3; scale bar = 100 um.

Tabanus abdominalis, food canal. Legend: A, spmn #1; B, spmn #3; c, chemoreceptor; m, mechanoreceptor. Note: Diameter/width of chemoreceptor = 14. 4 um. c m

Tabanus abdominalis, labrum with food canal (spmn #7). Dashed vertical line “p” is the proximal end of the food canal; dashed vertical line “d” is the distal end of the canal. 1. 0 mm “d” fc le = 2. 84 mm “p”

Tabanus abdominalis, labrum with food canal (spmn #7). Dashed vertical line “p” is the proximal end of the food canal; dashed vertical line “d” is the distal end of the canal. fc le = 2. 84 mm “d” 1. 0 mm “p” dilator muscles of cibarium?

Tabanus abdominalis labrum with food canal, composite (A). Box in A enlarged in B to show proximal ends of food canal walls (R, right wall; L, left wall, arrows). Dashed vertical line “p” is the proximal end of the food canal; dashed vertical line “d” is the distal end of the canal. 1. 0 mm fc le = 2. 84 mm A “p” “d” B L R

Tabanus abdominalis, labrum with food canal (spmn #7).