Sapromyza intonsa Loew 1847

Semelbauer, Marek & Kozánek, Milan, 2014, The immatures of lauxaniid flies (Diptera: Lauxaniidae) and their taxonomical implications, Zootaxa 3780 (3), pp. 401-454 : 430-434

Sapromyza intonsa Loew 1847

Living larvae cylindrical, glassy shining. Distal part of Malpighian tubules moderately and irregularly inflated. Egg ( Figs 24–26 ). Length 0.59–0.68 mm. Ridges sharp and few in numbers. Ribs dense. Apical pole with starlike collar.

First instar ( Figs 131, 132 ). Length 1.59–2.24 mm. The ventral organ peculiar, retaining the lobe-like appearance, but the large central sensila nested deep within the lobe and surrounded by 6 slender digitiform outgrowths. The lobe of ventral organ expands apically, consequently the second row of scraping cirri is shortened and a relatively large free area left over the mouth hooks. Medial row of scraping cirri developed. Labial lobe with strong spiny hairs on internal surface.

Cephaloskeleton ( Fig. 174 ). Length 0.17 mm (n=1). Mouth hooks strong, converging, compact; two teeth at apex; distal part more sclerotised comparing to the basal part. Parastomal bars strong, with longitudinal groove. Epistomal sclerite completely hyaline, almost unrecognisable. Subhypostomal sclerites converging. Ligulate sclerites small and rounded. Ventral bridge narrow. Dorsal bridge semilunar.

Second instar ( Figs 133, 134 ). Length 2.42–3.58 mm. The labial lobe with inner hairs. 8–10 scraping cirri in the third row. Other features essentially as in the third instar.

Cephaloskeleton ( Fig. 189 ). Length 0.39 mm (n=1). Mouth hooks very strong, broad in lateral view, converging, but apices parallel, two unequal teeth at apex. Intermediate sclerite robust, massive ventral bridge. Parastomal bars and the intermediate sclerite interconnected. Epistomal sclerite shorter than broad, arched from dorsal view. Subhypostomal sclerites converging, widened at anterior end; ligulate sclerites tiny. Dorsal bridge semilunar. Dorsal cornua broad in lateral view. Vertical plates narrower than dorsal cornua. Ventral cornua with posterior third hyaline, slightly convex. Cibarium hyaline.

Third instar ( Figs 135–140 ). Length 3.41–5.16 mm. The facial mask narrow, (up to 12 scraping cirri per row), the scraping cirri in first row with reduced number of apical papillae (3). The stalks of scraping cirri appear to be only slightly laterally flattened and longitudinally corrugated (possibly artefact of preparation for SEM, but it indicates that they are rather rounded on cross-section in living larva). The peristomal cirri monomorphic, stout and few in number. The ventral organ stout with 6 additional digitiform processes. The labial lobe with long internal hairs. The anterior spiracles fan shaped with 6 papillae. The body segments essentially bare; the first thoracic segment with broad belt of comb spines dorsally; the second thoracic segment smooth; the third thoracic segment with narrow band of comb spines dorsally. The processes of anal division barely developed. The sprouts of posterior spiracles basally inflated; the peristigmatic tufts long.

Cephaloskeleton ( Fig. 204 ). Length 0.54–0.58 mm. Mouth hooks strong, converging, apices subparallel. Intermediate sclerite shorter than mouth hooks. The parastomal bars and the intermediate sclerite fused via dorsal ridge; ventral bridge strong. Epistomal sclerite as a narrow transverse strip, arched in dorsal view; posterior hyaline plate rectangled. Subhypostomal sclerites converging, club-shaped. Ligulate sclerites tiny. Dorsal cornua slightly narrower comparing to the ventral cornua. Ventral cornua hyaline in the posterior third. Cibarium hyaline.

Figures

FIGURES 24 – 32. Eggs of Sapromyza intonsa, S. sexpunctata and Sapromyzosoma quadricincta. 24. S. intonsa, lateral view. 25. Same, detail of posterior tubercle. 26. Same, detail of the egg chorion. 27. S. sexpunctata, lateral view. 28. Same, detail of the posterior tubercle. 29. Same, detail of the apical end of the egg, ventral view. 30. S. quadricincta, dorsal view. 31. Same, detail of the posterior tubercle. 32. Same, detail of the egg chorion.

FIGURES 131 – 134. Sapromyza intonsa, first (131, 132) and second (133, 134) instars. 131. Cephalic segment, ventral view. 132. Detail of the ventral organ. 133. Cephalic segment, ventral view. 134. Detail of the ventral organ. A, antenna; LL, labial lobe; MH, mouth hook; MP, maxillary palpus; PC, peristomal cirri; SC, scraping cirri; VO, ventral organ.

FIGURES 174 – 176. Cephaloskeletons of first larval instar, dorsal (top), lateral (middle) and ventral (bottom) view. 174. Sapromyza intonsa. 175. S. sexpunctata. 176. Sapromyzosoma quadricincta. 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 189 – 191. Cephaloskeletons of second larval instar, dorsal (top), lateral (middle) and ventral (bottom) view. 189. Sapromyza intonsa. 190. S. sexpunctata. 191. Sapromyzosoma quadricincta. 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 135 – 140. Sapromyza intonsa, third instar. 135. Cephalic segment, ventral view. 136. Anterior spiracle, lateral view. 137. Thoracic segments, lateral view. 138. Abdominal segments, lateral view. 139. Last abdominal segments and the anal division. 140. Detail of the posterior spiracles, lateral view. A, antenna; A 4 – A 7, first to seventh abdominal segments; AD, anal division; AL, ambulatory lobe; CS, cephalic segment; DP, dorsal process; LL, labial lobe; LP, lateral process; MH, mouth hook; MP, maxillary palpus; PC, peristomal cirri; PS, posterior spiracles; SC, scraping cirri; T 1 – T 3, first to third thoracic segments; VO, ventral organ.

FIGURES 204 – 206. Cephaloskeletons of third larval instar, dorsal (top), lateral (middle) and ventral (bottom) view. 204. Sapromyza intonsa. 205. S. sexpunctata. 206. Sapromyzosoma quadricincta. a, apodeme of ventral cornu; apoc, 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.