Quichuana pogonosa Fluke, 1937

Echeverry, Angela, Souza, Diego de S. & Marinoni, Luciane, 2021, Description of the immature stages, biology and DNA-barcoding of Quichuana pogonosa (Diptera: Syrphidae) collected in Bromeliaceae in Paraná, Brazil, Zoologia (e 21004) 38, pp. 1-10 : 3-8

Quichuana pogonosa Fluke, 1937

Type locality: Brazil, Santa Catarina, Nova Teutônia. Distribution: Venezuela, Brazil. Holotype male, American Museum of Natural History , New York. Type locality: Brazil, Santa Catarina, Nova Teutônia. Distribution: Venezuela, Brazil.

Fluke and Plaumann 1937: 5 (fig. 14, head of female); 11 (original descriptions); Hull 1946: 2 (key to species); 15 (fig. 8, face of female paratype); Thompson 1972: 135 (fig. 50, male genitalia); Morales and Köhler 2008: 44 (list), 46 (list); Ricarte et al. 2012:102 (fig. 55, right antennae, lateral inner view), 108 (diagnostic features), 125 (key to species).

Egg ( Fig. 1 )

Length: 0.94 ± 0.04 mm; width: 0.51 ± 0.07 mm (n = 2). White colour, oval in shape, twice as long as wide. Opercular region flatten. Chorionic surface with microsculpture made up of longitudinal rectangular units evenly distributed throughout the egg. Operculum as a truncated cone.

Examined material. Site 1: 10 exemplars (two unhatched eggs and 8 shells from hatched eggs; all deposited together under DZUP 690901).

First instar larva

Length: 2.63 ± 0.09 mm; width: 0.83 ± 0.05 mm (n = 3). Examined material. Site 1: 3 exemplars (all deposited together under DZUP 690902).

Third instar larva ( Figs 2–6 )

Length: 11.50 ± 0.58 mm; width 4.0 mm (n = 3). Overall appearance: long-tailed, sub-cylindrical in cross-section with flattened ventral surface; truncate anteriorly, tapering posteriorly to anus. Cuticle transparent when alive; beige to dark-brown after fixation; covered with tiny spicules directed backwards and beige-colored at base and dark-brown at apex.

Head. Mouthparts internal: base of papilla with pair of fleshy projections; apex of each projection with well-developed antennomaxillary organ divided at base. Cephalopharingeal head skeleton: mandibles and mandibular lobes internal. Cibarial camera located in the ventral cornu, with six transverse branched ridges. Ventral cornu elongate. Dorsal cornu triangular, shorter than ventral cornu, attached to dorsal bridge.Dorsal bridge joining the two dorsal cornua.Vertical plate sclerotized.Mandibular lobes ovoid at base, coupled with mandibles.Labrum slightly sclerotized.

Thorax. Dorsal surface of prothorax with four longitudinal grooves, dorso-apical margin curving down towards front of head, with sclerotized hooked spicules directed backwards. Opercular suture as a line on dorsolateral margin, from prothorax to abdominal segment 1. Dorso-lateral surface with a pair of brown and shiny spiracles; length: 0.81 ± 0.11 mm; width: 0.40 mm; distance between spiracles: 1.36 ± 0.18 mm; slightly acuminate, curved tips and crenate at margin; retractile into inverted integumental pockets; with 12 to 14 facets at apex surrounding about half the circumference. Lateral lips well-developed, apex triangular with conical hooks, inner margin with six long setae with forked apex; base enlarged with conical hooks; inner margin covered with very fine pubescence, as a first filter anterior to oral cavity. Dorsal lip with a tuft of long unpigmented setae, situated below antennomaxillary organs; ventral lip not clearly visible. Ventral surface with well-developed prolegs bearing 16–18 crochets arranged in two semicircular rows, crochets on first row long, crochets on second row about half the length of crochets on first row. Several rows of spicules ventral to second row.

Abdomen. Segment 1 with primordia of pupal spiracles as two circular patches with weak pubescence (see w in Figs 5, 6 ). Segments 1–6 with well-developed conic prolegs; with two semicircular lines bearing 16–18 crochets each, directed posteriorly; prolegs of segment 6 with large crochets directed anteriorly. Segment 8 length: 13.83 mm ± 7.61 mm; width at base: 3 mm; width at apex: 1 mm. Posterior respiratory process with four pairs of weakly developed lappets with one sensilla on each one; light brown, ringed at base; apical spiracular disc with two apertures surrounded by eight long plumose interspiracular setae.

Chaetotaxy. Prothorax with four pairs of dorsal sensilla, one pair of lateral and one pair ventrolateral on lateral lips. Mesothorax with three pairs of dorsal sensilla, one pair lateral and one pair ventrolateral very close to proleg. Metathorax with four pairs of dorsal sensilla, one pair lateral, one pair ventrolateral and one pair ventral. Abdominal segments 1–6 with four pairs of dorsal sensilla, two pairs lateral, one pair ventrolateral and one pair posterior to each proleg. Abdominal segment 8 with two pairs of dorsal sensilla, two pairs lateral and one pair ventrolateral. Ventrally, with long setae on ventrolateral margins and posterior to anus.

Examined material. Site 1: 3 exemplars ( DZUP 690903, DZUP 690904, DZUP 690905).

Puparium ( Figs 7–10 )

Length: 7,18 ± 1, 32 mm; width: 4.40 ± 0.62 mm (n = 12). Subcylindrical in cross-section; truncated anteriorly; tapered posteriorly, flattened ventrally. Integument brown, weakly rough, with transverse folds and wrinkles exhibiting larval mouth, prolegs and anal papillae.

Pupal spiracles. Length: 1.41 ± 0.19 mm; width: 0.24 ± 0.02 mm; distance between each respiratory process: 1.29 ± 0.36 mm. Subcylindrical, projecting towards center of operculum, black, slightly curved at apex, apical surface bearing irregularly spaced and circular-shaped tubercles.

Examined material. See examined material under ‘Adults’.

Adults ( Figs 11–14 )

Male genitalia. Surstylus elongate, curved, with truncate apex; ventral and dorsal surfaces with long dark brown bristles near apex; basal surface with short and spaced dark brown bristles. Cercus triangular bearing setulae. Hypandrium piriform; apex with a pair of hook-like projections. Epandrium elongated, about four times as long as wide. Aedeagal lobe triangular.

Examined material. Site 1: 1 female (collected in oviposition) ( DZUP 690907 ) ; 1 female, emergence 15.xii.2020 ( DZUP 690908 ) , 1 male, emergence 15.xii.2020 ( DZUP 690909 ) ; 1 male, pupation 4.i.2021, emergence 15.i.2021 ( DZUP 690910 ) ; 1 female, pupation 22.i.2021, emergence 2.ii.2021 ( DZUP 690911 ) ; 1 female, pupation 4–5.ii.2021, emergence 15.ii.2021 ( DZUP 690912 ) ; 1 female, pupation 8.ii.2021, emergence 18.ii.2021 ( DZUP 690913 ) ; 1 female, pupation 19.ii.2021, emergence 3.iii.2021 ( DZUP 690914 ) ; 1 male, pupation 19.ii.2021, emergence 3.iii.2021 ( DZUP 690915 ) ; 2 females ( DZUP 690916 ), ( DZUP 690917 ) ; 1 male ( DZUP 690918 ) ; Site 2: 1 male, pupation 8.ix.2021, emergence 22.ix.2021 ( DZUP 690906 ) .

Life history ( Figs 15–20 )

A female was observed in situ ovipositing on the water surface of the phytotelmata of Alcantarea imperialis . In the same plant there were other long-tailed larvae at different stages of Quichuana , Eristalis Latreille, 1804 , and Lejops Rondani, 1857 . Pupae and puparia of different species were also observed together attached to dry leaves.

At the laboratory, the collected eggs hatched 56 hours after they were laid. The newly hatched larvae feed on their eggshell. First and second instar larvae were observed feeding on small invertebrates, zooplankton and organic matter in the water column. The third instar larvae were observed feeding on organic matter down the bottom of the container. When at rest, the larvae remained hidden at the bottom of the tank, between the sediment and the leaves, using their prolegs to adhere to the leaves. The posterior respiratory process remained extended with the spiracular disc in contact with the water surface, allowing them to breathe and feed at the same time.

It took the larvae 61–62 days to complete their development. When the third instar larvae were ready to pupate, they migrated to the dry leaves. The pupae adhered to the leaves using their anal papillae. The pupal spiracles appeared 24 hours after pupation. The pupal stage lasted 11–13 days.

DNA-barcoding

In order to facilitate the identification of immature stages,sequences of the barcoding region (cox1; 658 bp) were generated for two larvae and two adult specimens.The sequences were deposited on GenBank under the following accession numbers: MZ389870 and MZ389871 (larvae), MZ389868 and MZ389869 (adults).Intraspecific variation among these sequences ranged from 0 to 0.046% for both p-distances and K2P estimations ( Table 2 ).

Figures

Figures 1–6. Quichuana pogonosa: (1) egg; (2) habitus of third instar larva, lateral view (DZUP 690903); (3) third instar larva, ventral view (DZUP 690903); (4) cephalopharyngeal skeleton of third instar larva, lateral view; (5) third instar larva, dorsal view (DZUP 690903); (6) map of the chaetotaxy of the third instar larva in lateral view showing the position of the sensillae. (a1, a7, a8) abdominal segments a2–a6 are suppressed from the figure for clarity; (a) anus; (am) antennomaxillary organs; a pr, abdominal prolegs; (a sp l) anterior spiracles larval; (c) cibarium; (cs) chorionic surface; (d) dorsal; (dc) dorsal cornu; (db) dorsal bridge; (ep) epipharyngeal plate; (l) lateral; (lb) labial bridge, (lbr) labrum; (lg) longitudinal grooves; (lr) labial rods; (ll) lateral lip; (lp t) lappets; (m) mouthparts; (mi) mandibular lobes; (m pr) mesothoracic proleg; (ms) mesothorax; (mt) metathorax; (od) optical depression; (op) operculum; (p) prothorax; (v) ventral; (va) ventral arm; (vc) ventral cornu; (vl) ventrolateral; (vp) vertical plate; (w) primordia of pupal spiracles; (wl) line of weakness after puparia formation bounding the operculum. Scale bars: 1, 4 = 0.5 mm, 2 = 5 mm, 3, 5 = 2 mm.

Figures 7–10. Quichuana pogonosa: (7) pupa, dorsal view (DZUP 690906); (8) pupa, ventral view (DZUP 690906); (9) operculum (DZUP 690914); (10) puparium, dorsal view (DZUP 690914). (a sp l) anterior spiracles larval; (a pr) abdominal prolegs; (ap) anal papillae; (ce) cephalopharyngeal skeleton; (op) operculum; (sp p) pupal spiracles. Scale bars: 2 mm.

Figures 11–14. Quichuana pogonosa, male (DZUP 690906): (11) habitus dorsal; (12) habitus lateral; (13) genitalia, ventral view; (14) genitalia lateral view. (aed lb) aedeagal lobe, (cerc) cercus, (epand) epandrium, (hypd) hypandrium, (phapod) phallodeme, (sur) surstylus. Scale bars: 11, 12 = 2 mm, 13, 14 = 1 mm.

Figures 15–20. Quichuana pogonosa: (15) egg; (16) first instar larvae next to shells; (17–18) habitus of third instar larvae; (19) pupae aggregation; (20) puparia of Quichuana pogonosa (left) and Eristalis sp. (right).