Culicoides shemanchuki Grogan & Lysyk

Shults, Phillip & Borkent, Art, 2018, Pupae of the Nearctic species of Culicoides Latreille subgenus Monoculicoides Khalaf (Diptera: Ceratopogonidae), Zootaxa 4504 (4), pp. 451-472 : 463-465

Culicoides shemanchuki Grogan & Lysyk

( Figs. 2A , 5A )

Diagnosis. The only species of C. ( Monoculicoides ) with 5 pores on the subbasal portion of the respiratory organ ( Fig. 2A ) and D–5–T equal in length to D–1–T and D–2–T ( Fig. 5A ).

Description. Male. Total length = 2.95 mm (n=1). Medium brown coloration throughout. Head: Dorsal apotome (DA) covered in short spicules. DA length = 0.32 mm (n=1); DA width = 0.18 mm (n=1); DAW/DAL= 0.563 (n=1). Thorax: Cephalothorax length = 1.26 mm (n=1). Respiratory organ (RO) elongate, slender, 5 subbasal pores ( Fig. 2A ). RO length = 0.34 mm (n=1); RO width = 0.04 mm (n=1); ROW/ROL = 0.118 (n=1). D–1–T, D–2– T, D–5–T long, stout, equal in length, each on rounded tubercle in longitudinal row ( Fig. 5A ). Abdomen: Tergite 1 with long D– 3–I, short D– 2–I, D– 7–I anterior, short D– 4–I, and long, thin D– 9–I separated medially by campaniform D– 8–I on short tubercle posteriorly, L– 2–I, L– 3–I short separated medially by long, thin L– 1–I on lateral margin. Chaetotaxy, shagreen of tergite 2 similar to tergite 4, without elongate tubercles, small L– 2–II, L– 4– II separated medially by thin L– 3–II on anterolateral margin. Chaetotaxy, shagreen of segment 3 similar to that of segment 4. Tergite 4 with short D– 2–IV, thin D– 3–IV on short tubercle, D– 5–IV, D– 4–IV, D– 7–IV, D– 8–IV, D– 9– IV in transverse row, arranged medially to laterally, minute D– 5–IV on slightly formed tubercle, D– 4–IV on small tubercle, D– 7–IV on small rounded tubercle, D– 8–IV, D– 9–IV each long on rounded tubercle, D– 8–IV seta thicker than D– 9–IV; lateral tubercles with elongate, slender apices, L– 1–IV thick seta on bifurcate tubercle, L– 2–IV, L– 4– IV thick setae, each on elongate bifurcate tubercle, separated by thin L– 3–IV on elongate bifurcate tubercle; sternite 4 with minute V– 5–IV on small rounded tubercle, V– 6–IV thin on rounded tubercle, V– 7–IV on rounded tubercle, ventral setae in transverse row, shagreen along anterior margins, no lateral shagreen. Segments 5–7 with similar chaetotaxy, shagreen to that of segment 4, D–9 tubercles becoming more pointed with subsequent segments. Segment 8 chaetotaxy with seven sensilla, without lateral shagreen. Segment 9 with anterior shagreen, anterior margin not strongly modified.

Female. Similar to male other than sexual differences on segment 9 and the following: total length = 3.57 mm (n=1), DA length = 0.27 mm (n=1), DA width = 0.21 mm (n=1), DAW/DAL = 0.77 (n=1), Cephalothorax length = 1.35 mm (n=1), RO length = 0.36 (n=1), RO width = 0.04 mm (n=1), ROW/ROL = 0.11 (n=1).

Taxonomic discussion. The coloration of the pupa of C. shemanchuki is similar to that of C. riethi ( Fig. 1 ) but it has much less lateral shagreen on its abdominal segments. This species has 4-5 subbasal pores on the respiratory organ, and is the only C. ( Monoculicoides ) we examined to have 5. However, we only examined two specimens and there is a significant possibility that there could be greater variation in the number of subbasal pores ( Lawson 1951). Both specimens examined had folded dorsal apotomes, which made it difficult to obtain accurate measurements, descriptions, and photographs of this structure.

This species is known only from southern Alberta and north-central North Dakota ( Grogan & Lysyk 2015).

Material examined: 1 male, 1 female ( CNCI), USA, North Dakota, Pierce Co, Pleasant Lake , June 1969, W.W. Wirth, alkaline lake .

Figures

FIGURE 1. Habitus of the pupae of Culicoides occidentalis (left) and C. riethi (right) in dorsal view.

FIGURE 2. Respiratory organs, in lateral view. (A) Culicoides shemanchuki. (B) C. occidentalis.

FIGURE 5. Thoracic dorsal setae, left side, dorsal view. (A) Culicoides shemanchuki. (B). C. occidentalis.