Aprostocetus nebraskensis (Girault), 1916

Johnson, Paul J., Yefremova, Zoya A., López, Juan Manuel Perilla & Yegorenkova, Ekaterina N., 2018, Aprostocetus chilophagae new species (Hymenoptera: Eulophidae) from South Dakota, with taxonomic notes on A. bromi (Kostjukov) and A. nebraskensis (Girault), Zootaxa 4514 (4), pp. 473-486 : 482-484

Aprostocetus nebraskensis (Girault)

( Figs. 12 b–17)

Neomphaloidella nebraskensis Girault 1916: 103 .

Tetrastichus nebraskensis , of Burks 1943: 594; Boe and McDaniel 1990: 208

Aprostocetus nebraskensis , of LaSalle 1994: 148

Type material examined. Holotype ♀, Ñ 19914 . U.S. N.M., Neomphaloidella nebraskensis Girault, 1916 , ♀, type. Lincoln Neb, G.I. Reeves collector, Webster Ñ 2142 ( U.S. N.M, examined) . Paratypes, 4 ♀, with same data as holotype .

Additional material examined. U.S.A., South Dakota, Brookings Co., Aurora Farm, 44°18'22''N, 96°40'15''W, coll. M Perilla / captured by aspirator on inflorescences of Andropogon gerardii , Stenodiplosis wattsi Gagné , 29.vii.2014 (3 ♀, SDSU); Oak Lake field Station, 44°30'39''N, 96°31'47''W sampled 24.vii.2015, reared from Stenodiplosis wattsi Gagné on Andropogon gerardii , emerged 8.viii.2015, coll M Perilla Lopez (1 ♂, SDSU); Aurora, 44°18'22''N, 96°40'15''W sampled 23.vii.2015, reared from Stenodiplosis wattsi Gagné on Andropogon gerardii , emerged 15.viii.2015, coll M. Perilla Lopez (3 ♀, 1 ♂, SDSU); Felt farm, 44°22'08''N, 96°47'40''W sampled 4.viii.2015, reared from Stenodiplosis wattsi Gagné on Andropogon gerardii , emerged 06-25.viii.2015, coll M Perilla Lopez (17 ♀, 9 ♂, SDSU).

Diagnosis. Distance between submedian lines 1.3 times as long as distance between submedian and lateral lines; mesoscutum with 3 adnotaular setae, propodeal callus with 2 setae in one row. POL 1.3–1.5 times as OOL. Antenna F1 1.25 times as long as F2, forewing 2.4 times as long as broad. Dorsellum as long as propodeum.

Description. Female: Body length 1.0– 1.3 mm. Forewing 0.9–1.1 mm. Body brown. Head brown; radiculus of antenna yellow, flagellum brown; antennal club brown, same color as flagellum, eye reddish. Mesosoma mostly brown, metanotum yellow ( Figs 13, 15 ). Tegulae yellow. Mesopleural sutures yellow ( Fig. 14 ). Leg with coxa brown, trochanter yellow; femur and tibia brown in middle; last tarsomere of hind tarsus yellow and tarsomeres 2, 3 and 4 brown. Gaster brownish.

Head 1.2 times as broad as tall; eye height 2.0 times as long as malar space. Mandibles with 3 big teeth, maxilla 2-segmented, labium 1-segmented. POL 1.5 times as OOL. Antenna ( Fig. 4 ) with scape 3.5–3.6 times as long as broad; pedicel 2.0–2.2 times as long as broad; three anelli (1 discoid and 2 laminar); F1 2.6 times as long as broad; F2 1.9–2.0 times as long as broad; F1 1.25 times longer than F2; F3 1.7 times as long as broad; clava 3- segmented with F11 (terminal spine); 2.7–2.8 times as long as broad.

Mesosoma 1.2 times as long as broad; mesoscutum 1.3 times as broad as long, notauli with 3 long adnotaular setae, median line distinct; metascutellum 1.1 times as long as broad smooth. Distance between submedian lines 1.8 times as long as distance between submedian and lateral ( Fig. 13 ). Propodeum 5.0 times as broad as long, smooth between median carina and postspiracular groove; callus with 2 setae in one row. Dorsellum as long as propodeum.

Forewing 2.4–2.5 times as long as broad; relative lengths of venation: MV 2.1–2.2 times as long as SMV and 3.3 times as long as STV. SMV with 3 setae, MV with 13 setae. Hindwing 3.6 times as long as broad, apically broadly rounded.

Petiole transverse, small, smooth; gaster 1.5–1.7 times as long as broad, smooth. Cercus with 5 setae, the longest 1.8 times as long as others.

Male: Body length 1.3–1.6 mm. Color as in female. Metanotum yellow to dark brown, gaster brownish (from 11 males, 3 specimens have yellow T1+T2); light brownish vittae along notauli and between median and lateral lines on scutellum ( Fig. 17 ). Mesopleural suture yellow. Leg with coxa brown, trochanter yellow; ca. 0.75X length of femur brownish; last tarsomere brownish and tarsomeres 2, 3 and 4 yellow. Gaster brownish ( Fig. 16 ).

Antenna with scape 3.2–3.8 times as long as wide, with ventral plaque about 0.25–0.3 length of scape, situated distally; pedicel 1.5 times as long as wide, with 3 anelli (two discoid anelli and third laminate) and 4 flagellomeres, with whorled setae; F1 1.4–1.5 times as long as broad; F2 1.9–2.0 times as long as broad, and 1.1–1.2 times as long as F1; F3 2.4–2.6 times as long as wide and as long as F4; F4 2.4–2.7 times as long as wide; clava 3-segmented, 5.8–6.5 times as long as broad and 2.2 times as long as F4. Whorled setae of F1 reaching half of F4, whorls of F2 reaching half of F4, whorls of F3 reaching half of C1, whorls of F4 reaching middle of C2, whorls of C1 reaching top of C3, whorls C2 and C3 extend the top of clava and F11 (terminal spine) 0.1 of length of clava.

Mesosoma 1.6 times as long as broad; mesoscutum 1.2 times as broad as long, notauli with 3 long adnotaular setae, median line distinct, metascutellum 1.2 times as long as broad. Forewing ( Fig. 16 ) 1.8–2.3 times as long as broad; SMV with 3–5 setae, and MV with 10–12 setae and 2.0–2.5 times as long as SMV and 3.3–3.6 times as long as STV. Speculum small extending along ¼ of MV and closed.

Petiole transverse, small, smooth; gaster 2.8–3.3 times as long as broad.

Distribution. U.S.A., Florida, Nebraska, New Mexico, South Dakota.

Hosts. Dasineura leguminicola Lintner , and Stenodiplosis wattsi Gagné ( Diptera : Cecidomyiidae ). Dasneura leguminicola is associated with Medicago sativa L., Trifolium pratense , and T. medium L. ( Fabaceae ) (Burks 1979, LaSalle 1994, Gagné & Jaschhof 2014). These host records are doubtful and require confirmation given changing views on Aprostocetus taxonomy and host associations. However, throughout the U.S.A. these legumes grow intermingled with B. inermis and other other grasses. Stenodiplosis wattsi is a verified host and associated with Andropogon gerardii , Schizachyrium scoparium , and Sorghastrum nutans ( Boe & McDaniel 1990, Gagné & Jaschhof 2014, Perilla López et al. 2015a).

Comments. Aprostocetus bromi and A. nebraskensis are superficially similar, but are distinct in the female antenna ( Figs. 1–3 , Fig. 4 ) and the male F1 1.4–1.5 times as long as broad, F3 2.4–2.6 times as long as wide, clava 5.8–6.5 times as long as broad; whorled setae of F1 reaching half of F4 (F1 1.05–1.1 times as long as broad, F3 2.1–2.3 times as long as wide; clava 5.4–5.8 times as long as broad; whorled setae of F1 reaching half of F 3 in A. bromi ); distance between submedian lines/submedian and sublateral lines 1.8 (1.6 in A. bromi ), mesopleural sutures yellow (brown as mesoscutum in A. bromi ), dorsellum yellow (brown as propodeum in A. bromi ). A comparison of important characters and with A. chilophagae is given in Table 2.

Figures

FIGURES 11–12. Antennae of male Aprostocetus bromi and A. nebraskensis:. 11, A. bromi reared from S. bromicola on B. inermis (South Dakota); 12a, A. bromi reared from Stenodiplosis spartinae on Spartina pectinata (South Dakota); 12b, A. nebraskensis male (South Dakota).

FIGURES 13–15. Female, Aprostocetus nebraskensis: 13, mesosoma, dorsal (Type USNM); 14, mesosoma, dorso-lateral (Type USNM); 15, mesoscutellum, dorsellum and part of propodeum, dorsal view (South Dakota).

FIGURES 1–4. Antennae of female Aprostocetus bromi (Kostjukov) and A. nebraskensis (Girault): 1, A. bromi (Kostjukov) (Paratype, ZISP); 2, A. bromi reared from Stenodiplosis bromicola on Bromus inermis (South Dakota); 3, A. bromi reared from Stenodiplosis spartinae on Spartina pectinata (South Dakota); 4, Antenna of A. nebraskensis (Girault) (Type USNM).

FIGURES 16–17. Male, Aprostocetus nebraskensis: 16, body, dorso-lateral view (South Dakota); 17, mesoscutellum, dorsellum and part of propodeum, dorsal view (South Dakota).