Poecilolycia vittata (Walker 1849)

Semelbauer, Marek & Kozánek, Milan, 2014, The immatures of lauxaniid flies (Diptera: Lauxaniidae) and their taxonomical implications, Zootaxa 3780 (3), pp. 401-454 : 421-425

Poecilolycia vittata (Walker 1849)

Living larvae translucent, dorsoventrally flattened and with marked welts and crevices. The Malpighian tubules moderately expanded and form a typical ventral loop; in the first instar filled with white matter, in the second and third instars the loop filled with light-orange matter, remaining parts of the tubules filled with white matter; more intensive colours are typical for the older larvae.

Egg ( Figs 15–17 ). Length 0.65–0.69 mm. Chorion with dense and marked ridges. Dorsal side of egg with elongated spines on the ridges, ventral side without spines, but edge of the ridges undulated.

First instar ( Figs 93, 94 ). Length 1.08–2.23 mm. Number of scraping cirri per row large (<40), before the first row is one more row of small cirri. The peristomal cirri filamentous, arranged almost in horizontal row. The ventral organ essentially lobate, peculiar. The ambulatory lobes slender, appear two-segmented. The sprouts of posterior spiracles swelled; peristigmatic tufts long.

Cephaloskeleton ( Fig. 170 ). Length 0.27–0.28 mm. Mouth hooks with 10–12 teeth, stalked part hyaline and slender. Intermediate sclerite and parastomal bars almost equal in diameter; ventral bridge broad and strongly arched in ventral view. The epistomal sclerite convex, longer than broad, with apical tooth. Subhypostomal sclerites opposite.

Second instar ( Figs 95–98 ). Length 2.02–4.11 mm. Facial mask broad, up to 30 of scraping cirri per row. The peristomal cirri differentiated in two types: filamentous and flat triangular. The body segments covered by stout spines; the first thoracic segment smooth; the processes of anal division stout, ambulatory lobes slender, twosegmented.

Cephaloskeleton ( Fig. 185 ). Length 0.46–0.49 mm. Mouth hooks week, basal third converging, otherwise parallel, 5 apical teeth. The epistomal sclerite rounded. The intermediate sclerite slender; ventral bridge broad and descending posteriad. Subhypostomal sclerites as horizontal perforated plates. Ligulate sclerites as vertical converging plates. Dorsal bridge narrow, equally broad along whole length. Dorsal cornua week, shorter than ventral ones. Posterior half of ventral cornua hyaline with sclerotised and convex dorsal margin. Basal part of dorsal and ventral cornua and vertical plates finely striolated. Cibarium slightly pigmented, inter-ridge distances large.

Third instar ( Figs 99–104 ). Length 3.13–6.19 mm. The facial mask very similar to previous instar, up to 40 scraping cirri per row. Labial lobe very short, trilobite. The anterior spiracles fan-shaped, with 9 papillae, one apparently fused from several papillae. The first thoracic segment smooth, the second one sparsely covered by spines dorsally; rest body segments covered by stout spines. The anal division as in previous instar.

Cephaloskeleton ( Fig. 200 ). Length 0.81–0.82 mm. Mouth hooks weak, straight and slightly converging. The epistomal sclerite rounded and convex. Remaining features largely as in the second instar, but the ventral cornua almost completely slightly sclerotised.

Figures

FIGURES 15 – 23. Eggs of Poecilolycia vittata, Pseudolyciella pallidiventris, Sapromyza hyalinata and S. apicalis. 15. P. vittata, lateral view. 16. Same, detail of the posterior tubercle. 17. Same, detail of the egg chorion. 18. P. pallidiventris, ventral view. 19. Same, detail of the posterior tubercle. 20. Same, detail of the egg chorion. 21. S. hyalinata, ventral view. 22. Same, detail of the posterior tubercle. 23. S. apicalis, ventral view.

FIGURES 93 – 98. Poecilolycia vittata, first (93, 94) and second (95 – 98) instars. 93. Cephalic segment, ventral view. 94. Detail of the ventral organ. 95. Cephalic segment, ventral view. 96. Detail of the facial mask. 97. Thoracic and abdominal segments, dorsal view. 98. Last abdominal segments and the anal division, dorsal view. A 1 – A 7, first to seventh abdominal segments; AD, anal division; AL, ambulatory lobe; AS, anterior spiracles; CS, cephalic segment; DP, dorsal process; LL, labial lobe; LP, lateral process; MH, mouth hook; PC, peristomal cirri; PS, posterior spiracles; SC, scraping cirri; SC 1, first row of scraping cirri; T 1 – T 3, first to third thoracic segments; VO, ventral organ.

FIGURES 168 – 173. Cephaloskeletons of first larval instar, dorsal (top), lateral (middle) and ventral (bottom) view. 168. Minettia loewi. 169. M. plumicornis. 170. Poecilolycia vittata. 171. Pseudolyciella pallidiventris. 172. Sapromyza apicalis. 173. S. hyalinata. c, cibarium; db, dorsal bridge; dc, dorsal cornua; dmh, distal part of mouth hook; es, epistomal sclerite; is, intermediate sclerite; lb, labrum; ls, ligulate sclerite; smh, stalked part of mouth hook; pb, parastomal bar; ss, subhypostomal sclerite; vb, ventral bridge; vc, ventral cornua; vp, vertical plate.

FIGURES 183 – 188. Cephaloskeletons of second larval instar, dorsal (top), lateral (middle) and ventral (bottom) view. 183. Minettia loewi. 184. P. litura. 185. Poecilolycia vittata. 186. Pseudolyciella pallidiventris. 187. Sapromyza apicalis. 188. S. hyalinata. a, apodeme of ventral cornu; c, cibarium; db, dorsal bridge; dc, dorsal cornua; es, epistomal sclerite; is, intermediate sclerite; lb, labrum; ls, ligulate sclerite; mh, mouth hook; pb, parastomal bar; r, rami; ss, subhypostomal sclerite; vb, ventral bridge; vc, ventral cornua; vp, vertical plate.

FIGURES 99 – 104. Poecilolycia vittata, third instar. 99. Cephalic segment, ventral view. 100. Anterior spiracle, lateral view. 101. Thoracic segments, lateral view. 102. Abdominal segments, lateral view. 103. Last abdominal segment and the anal division, dorsal view. 104. Abdominal segments, dorsal view. A 2 – A 7, second to seventh abdominal segment; AD, anal division; AL, ambulatory lobe; DP, dorsal process; LL, labial lobe; LP, lateral process; MH, mouth hooks; PC, peristomal cirri; PS, posterior spiracles; SC, scraping cirri; T 1 – T 3, first to third thoracic segments.

FIGURES 198 – 203. Cephaloskeletons of third larval instar, dorsal (top), lateral (middle) and ventral (bottom) view. 198. Minettia plumicornis. 199. P. litura. 200. Poecilolycia vittata. 201. Pseudolyciella pallidiventris. 202. Sapromyza apicalis. 203. S. hyalinata. a, apodeme of ventral cornu; c, cibarium; db, dorsal bridge; dc, dorsal cornua; es, epistomal sclerite; is, intermediate sclerite; lb, labrum; ls, ligulate sclerite; mh, mouth hook; pb, parastomal bar; r, rami; ss, subhypostomal sclerite; vb, ventral bridge; vc, ventral cornua; vp, vertical plate.