Coptera tonic, Ericson & Forbes, 2020

Ericson, Hannah C. & Forbes, Andrew A., 2020, Description of the new species Coptera tonic (Hymenoptera, Diapriidae), a pupal parasitoid of Rhagoletis juniperina Marcovitch (Diptera, Tephritidae), and revised partial keys to Nearctic Coptera Say, ZooKeys 985, pp. 49-60 : 49

Coptera tonic sp. nov. Figures 1-4 , 5-8

Type material.

Holotype: USA • ♀; Ingham Co., East Lansing, MI; 42.7274, -84.4777; 3 Jul. 2011; Serdar Satar; reared from soil-collected pupa of Rhagoletis juniperina ; UIMNH ID: SUI:INS:04567.

Paratypes: USA • ♀; Ingham Co., East Lansing, MI; 42.7274, -84.4777, 21 Aug. 2011; Serdar Satar; reared from pupa of R. juniperina , SUI:INS:04568 • 6♂; ibid; 8-9 Aug. 2011; SUI:INS:04569-04573, 04576 • ♂; ibid; 13 Aug. 2011, yellow pan trap; SUI:INS:04577 • ♀; Johnson Co., Iowa City, IA, 41.6509, -91.5603, 11 Sep. 2011, Andrew Forbes; yellow pan trap; SUI:INS:04574 • ♂; ibid; 10 Sep. 2011; SUI:INS:04565.

Diagnosis.

Coptera tonic females (Figs 1-4 ) may be distinguished from female C. pomonellae (Figs 9-12 ) most readily by the distance between the apical punctures on the scutellum. In C. tonic , this distance is small, less than 1/2 of the shortest diameter of either puncture (Fig. 3 ), while in C. pomonellae the inter-puncture distance is subequal to the shortest diameter of each puncture (Fig. 11 ). Male C. tonic (Fig. 5 ) have each apical puncture partially or completely divided into two, such that there are indeterminately four apical punctures (Fig. 7 ), compared to the two standard punctures in male C. pomonellae (Fig. 15 ). Most flagellomeres of male C. tonic are 2-2.5 × longer than wide, with the apical segment 2.7-3.3 × longer than wide (Fig. 6 ), while the antennal segments of male C. pomonellae are shorter, less than 2 × as long as wide (final segment may approach 2.5 × as long as wide; Fig. 14 ). Coptera tonic of both sexes differ from C. cingulatae by the color of their antennae, which are dark brown to black in C. tonic and yellow to light brown in C. cingulatae (at least the first 3-4 flagellomeres; Figs 17 , 18 ).

Description.

Female. Length 3.0 - 3.1 mm; wing length 2.1 - 2.2 mm. Holotype length 3.0 mm; Holotype wing length 2.1 mm.

Color. Body (Fig. 1 ) black; legs, including coxae, honey yellow; antennal scape black; flagellum testaceous; eyes and 3 ocelli yellow to white; wings slightly infuscated.

Head. Head about as long as broad; dorsum of head normally with several large punctures (Fig. 2 ); distance from lateral ocelli to posterior margin of occiput longer than eyes; temples weakly round, in lateral view nearly as wide as eyes; malar space nearly half as long as eye; antennae strongly clavate and 12-segmented; first flagellomere twice as long as wide; second and third flagellomeres less than twice as long as wide but still longer than wide; all remaining flagellomeres wider than long.

Mesosoma. Pronotum smooth. Notaulices on mesoscutum fine and slightly broadened posteriorly; scutellum weakly convex; paired punctures at apex of scutellum moderately large and separated by less than the shortest diameter of either puncture (Fig. 3 ); mesopleuron not impressed medially; metapleuron not impressed medially; metapleuron densely hairy.

Metasoma. Petiole of abdomen about 1.5 times as long as wide; petiole with all three dorsal longitudinal carinae strong but median one reduced on some specimens (Fig. 4 ); median sulcus of large tergite not reaching or extending beyond middle of segment; basal lateral sulci not developed.

Male. Length 2.5-3.0 mm; wing length 2.1-2.3 mm.

Color. Body black; legs (including coxae) honey yellow; antennal scape black; flagellum testaceous; eyes and 3 ocelli tan; wings slightly infuscated.

Head. Head wider than long; dorsum of head normally with several large punctures; distances from lateral ocelli to posterior margin of occiput slightly longer than eyes, temples roundly receding, in lateral view slightly narrower than eyes; malar space nearly half as long as eyes; antennae slender with uniform thickness throughout, 14-segmented; all flagellomeres at least twice as long as wide with apical segment about three times as long as wide (Fig. 6 ).

Mesosoma. Pronotum smooth. Notaulices on mesoscutum fine, slightly broadened posteriorly; scutellum flat; paired punctures at apex of scutellum each subdivided into two smaller punctures (Fig. 7 ), though sometimes indistinctly; mesopleuron flat, not impressed medially; metapleuron densely hairy.

Metasoma. Petiole about 1.5 times as long as wide; petiole with all three dorsal longitudinal carinae strong and complete; median sulcus of large tergite not reaching the middle of the segment; basal lateral sulci not defined.

Etymology.

The species name is a noun in apposition and refers to tonic water; this parasitic wasp and tonic water are both at their best when in close association with products of Juniperus cones.

Ecology.

Coptera tonic is a parasitoid of the juniper maggot fly, Rhagoletis juniperina , a parasite of the female cones of Eastern red cedar ( Juniperus virginiana ) and other members of genus Juniperus . Though oviposition has not been directly observed in C. tonic , these wasps have only been reared from pupae floated from soils, and not from larvae extracted from juniper cones, suggesting that attack likely occurs during the fly’s pupal stage after it has left the cone. Some pan trap collections of C. tonic (e.g., the female paratype labeled "Crab Apple") were made under or near male Juniperus , suggesting that these wasps may use plant volatiles as an indicator for host searching. All known adults were captured or emerged from pupae between late July and early October ( Forbes et al. 2012), consistent with the phenology of R. juniperina pupation.

Distribution.

Existing collections of C. tonic are limited to Iowa and Michigan. However, Rhagoletis juniperina is distributed across the continental United States and into southern Canada ( Bush 1966, Frayer et al. 2015), so a wider distribution for C. tonic is possible, if not likely.

Figures

Figures 1 - 4. Female Coptera tonic 1 lateral habitus 2 dorsal view of head 3 dorsal view of mesosoma 4 dorsal view of petiole.

Figures 5 - 8. Male Coptera tonic 5 lateral habitus 6 antenna 7 dorsal view of mesosoma 8 dorsal view of petiole.

Figures 9 - 12. Female Coptera pomonellae 9 lateral habitus 10 dorsal view of head 11 dorsal view of mesosoma 12 dorsal view of petiole.

Figures 13 - 16. Male Coptera pomonellae 13 lateral habitus 14 antenna 15 dorsal view of mesosoma 16 dorsal view of petiole.

Figures 17, 18. Coptera cingulatae male and female; lateral habitus.