Copestylum oscillans, Rotheray & Hancock & Marcos-García, 2007

Rotheray, G. E., Hancock, E. G. & Marcos-García, M. A., 2007, Neotropical Copestylum (Diptera, Syrphidae) breeding in bromeliads (Bromeliaceae) including 22 new species, Zoological Journal of the Linnean Society 150 (2), pp. 267-317 : 276-277

003. COPESTYLUM OSCILLANS SP. NOV.

HANCOCK & ROTHERAY

Diagnosis – male holotype: Face yellow, with vague medial and lateral dark vittae, yellow haired except for a few black hairs near the tubercle ( Fig. 3 ); mesonotum mainly yellow with four black vittae forming a pair of black marks posteriorly; scutellum yellow with a pair of black apical markings; pleura yellow with black marked katepisternum, meron, and anterior part of the anepisternum; wing membrane hyaline, darker at the apical margin, R1 either open or closed apically in the costal vein; legs yellow except for darkened tibial apices; femorae black haired anteriorly, yellow haired posteriorly, tibiae and tarsi black haired; abdominal tergites 2–4 yellow, except for posterior margins that have black bands either narrowing or interrupted medially; sternites 1 and 2 yellow with yellow hairs; sternites 3 and 4 fuscous with black and yellow hairs; genitalia – surstylus broad and triangular-shaped with a straight outer margin and a curved inner margin; hypandrium lacking lateral projection; aedeagus with serrated apical margin ( Figs 29, 30, 31 ); female – similar to holotype male; width of vertex about 15% of width of head. Length: body, 9.16– 9.75 mm; wing, 8.75–9.16 mm (N = 4).

Diagnosis – larva and puparium: Suckers on abdominal segments 1–6; marginal band of fleshy lobes coated in long, fine, unbranched setae, present on abdomen only, not including the thorax ( Fig. 75 ); ventral surface of lobes on abdominal segments 1–6 coated in short, thick, stiff setae; vestiture of soft, fine setae lying flat; third pair of lappets included in the marginal band, and setulate ventrally almost to apex; posterior breathing tube orange, transverse ridge at mid-point, three pairs of spiracular openings, more or less parallel; pupal spiracles brown/black with openings clustered at widened apex.

Material examined – holotype: Male with puparium, Costa Rica, Alajuela, Upala, Dos Rios, 13 September 1999, ex water tank of Vriesea sanguinolenta (Bromeliaceae) , D. Briceño (INB0003056059) (INBio).

Material examined – paratypes: Two males and two females as follows – one male and one female with puparia, same data as holotype ( INB0003056054 , INB0003056055) ( INBio) ; one male and one female with puparia, Costa Rica, Alajuela, San Carlos, Fortuna , Est. Peninsula, 30 October 1999 (ex water tank of bromeliads), J. D. Gutiërrez ( NMS) .

Material examined – additional material: one larva, Costa Rica, Cartago NP, Tapanti , February 1999, GER ( NMS) ; one larva MAV-23 ( INBio) .

Etymology: The name ‘oscillans’ is descriptive of the characteristic back and forth movement of the posterior breathing tube during locomotion of the larva.

Taxonomic notes: The adult of C. oscillans can be distinguished by the presence of unique, paired, black markings on the otherwise yellow mesonotum and scutellum. Among the tank group species, C. oscillans is also unique in having a serrated apical margin to the aedeagus. Within the larval stages of the oscillans subgroup that have incomplete marginal bands and an orange posterior breathing tube, the early stages of this species are readily distinguished by the short, thick setae on the underside of the marginal lobes of the abdomen, setulate posterior lappets and more or less parallel spiracular openings of the posterior breathing tube. The early stages are most similar to those of C. tapanti , but C. oscillans is separated from that species by the parallel spiracular openings and brown/black, not yellow, pupal spiracles.

Biology: Adults were reared from larvae in water tanks of bromeliads including V. sanguinolenta , and are known only from Costa Rica.

Figures

Figures 1–6. Adult Copestylum, lateral view of the head; scale line = 3.5 mm. 1. Copestylum galantei sp. nov., male holotype; 2. Copestylum gelenita sp. nov., male holotype; 3. Copestylum oscillans sp. nov., male holotype; 4. Copestylum tacanense sp. nov., male holotype; 5. Copestylum tapanti sp. nov., male holotype; 6. Copestylum xalapensis sp. nov., female holotype.

Figures 23–31. Adult Copestylum, male genitalia; right and left figures scale line = 0.50 mm, for middle column figures, left-hand scale line = 0.85 mm. Abbreviations: a, aedeagus; c, cercus; e, epandrium; h, hypandrium; s, surstylus; sl, superior lobes. 23–25. Copestylum galantei sp. nov., male holotype: 23. genitalia and associated structures, lateral view; 24, hypandrium, ventral view; 25. surstylus, ventral view. 26–28. Copestylum gelenita sp. nov., male holotype: 26. genitalia and associated structures, lateral view; 27, hypandrium, ventral view; 28. surstylus, ventral view. 29–31. Copestylum oscillans sp. nov., male holotype: 29. genitalia and associated structures, lateral view; 30. hypandrium, ventral view; 31. surstylus, ventral view.

Figures 75–81. Third stage larvae of Copestylum. 75. Copestylum oscillans, whole larva, head to the right, ventral view, length = 11 mm. 76. Copestylum carlosii, whole larva, head to the right, ventral view, length = 10 mm. 77. Copestylum elizabethae, whole larva, head to the right, ventral view, length = 11 mm. 78. Copestylum carlosii, sucker from 4th abdominal segment, anterior end to the right, ventral view, width = 1 mm. 79. Copestylum oscillans, marginal lobe from 3rd abdominal segment, dorsal view, width = 0.35 mm. 80. Copestylum carlosii, marginal lobe from 3rd abdominal segment, dorsal view, width = 0.35 mm. 81. Copestylum elizabethae, marginal lobe from 3rd abdominal segment, dorsal view, width = 0.35 mm.