Amazonimyia gigantea, Silva, Fabio Laurindo Da & Wiedenbrug, Sofia, 2015

Silva, Fabio Laurindo Da & Wiedenbrug, Sofia, 2015, Amazonimyia gigantea gen. n., sp. n., a new Tanypodinae (Diptera: Chironomidae) from the Neotropical Region, Zootaxa 3947 (2), pp. 275-281 : 276-279

Amazonimyia gigantea sp. n.

Type material: Holotype male with pupal exuviae, Brazil, Amazonas, lower Rio Negro region, Manaus, Igarapé do Gigante, 2.vi.1961, sample number A 186-2, leg. E. J. Fittkau. Paratype: 1 pharate male data as holotype, except for sample number A 201- 2 and 20.vii.1961.

Etymology. Named after the stream, Igarapé do Gigante, where the specimens were collected.

Diagnosis. As given in generic diagnose of adult male and pupa.

Description. Adult male (n = 2 unless otherwise stated)

Size. Total length 3.8 (1) mm. Wing length 1.9 (1) mm. Total length/wing length 1.96 (1). Wing length/length of profemur 1.79.

Coloration. Head pedicel and antenna yellow-brown. Maxillary palp brown. Thorax pale brown; antepronotum pale. Legs pale. Wing with markings as in figure 1D, difficult to see when prepared in Euparal, covered with microtrichia and setae, which can be darker in the markings. Abdominal pale brown. Hypopygium pale brown.

Head ( Figs 1A–B ). Temporal setae 23–25. Eyes containing 3–4 terminal facets. Tentorium 223 (1) µm long, stipes not measurable. Clypeus 145–150 µm long, 103–125 µm wide at largest part, bearing 27–30 setae. Palpomere 1–5 lengths: 70 (1); 90; 140–155, 200; 325–330 µm. Antennal flagellum 1260–1360 µm long, diameter of pedicel 380 (1) µm, apical setae single (Fig. B), AR 1.96–2.23.

Thorax ( Fig. 1C ). Antepronotum with 6 lateral setae. Acrostichals 34–42, biserial; dorsocentrals 29–32; prealars 9–11; supraalar 1 (1). Anapleural suture ratio 0.54–0.65. Scutellum with 27–28 setae.

Wing ( Fig. 1D ). Width 0.6 (1) mm. Costa 1.3 (1) mm long. WW 0.31 (1). All veins and membrane setose (not drawn). Brachiolum with 2 (1) setae. Squama with 23 (1) setae.

Legs ( Figs 1E–G ). Fore leg: width at apex of tibia 58 µm, tibia with one apical spur 53 µm long and 6 side teeth ( Fig. 1E ); tibial apex with four long setae. Mid leg: width at apex of tibia 55–58 µm, tibia with two apical spurs 50– 53; 50–70 µm long, longest spur with 6–7 side teeth ( Fig. 1F ). Hind leg: width at apex of tibia 60–70 µm, tibia with two apical spurs 43–47; 83–88 µm long, longest spur with 6–8 side teeth ( Fig. 1G ); tibial comb with 7–8 bristles. Lengths and proportions as in Table 1.

fe ti ta1 ta2 ta3

p1 900–1075 1000–1325 850–1125 450–575 325–400 p2 1075–1225 950–1350 800–1100 400–525 200–275 p3 1075 1500 1150 575 375

ta4 ta5 LR BV SV

p1 210–300 140–150 0.84–0.85 2.44–2.47 2.13–2.23 p2 200–275 100–125 0.81–0.84 2.82–2.89 2.34–2.53 p3 275 150 0.77 2.71 2.24 Hypopygium ( Fig. 1H ). Tergite IX with 6–8 dorsal setae. Phallapodeme 60–85 µm long. Gonocoxite 220–260 µm long. Gonostylus 150–155 µm long; megaseta 15–18 µm long. HR 1.42–174. HV 2.52 (1).

Pupa (n = 2). Size. Male abdomen 3.9 mm long.

Coloration. Exuviae and thoracic horn pale brown.

Cephalothorax ( Fig. 2A ). Wing sheath 1275–1450 µm long. Thoracic horn as in figure 2A, 300–310 µm long and 45–48 µm wide; aeropyle tube simple, short, 13–15 µm long, lateral on % of thoracic horn length; corona with six apical openings ( Fig. 2A ). Thoracic comb with 12–14 short rounded tubercles.

Abdomen ( Figs 2B–E ). Tergite I with scar, 230–240 µm long. Shagreen on tergites I–VIII, sternites IV–VIII, paratergites I-VII and parasternites II–VII scale-like, consisted of rows of 2–4 small spinules fused at the base ( Fig. 2E ), shagreen on distal margin of segment formed by small and rounded spinules. Paratergites and parasternites VIII anteriorly with isolated spinules, posteriorly bare. Tergite IX with isolated spinules. Sternite I with very fine shagreen, difficult to see, parasternites bare, sternite II with shagreen consisted of groups of spinules, not fused at the base. Sternite III with scale-like shagreen, except anteromedial region with shagreen composed of isolated spinules. Chaetotaxy as in figures 2B–D. Segment I with 2 L-setae, II with one L- seta and one short taeniate L-setae, III-VI with 1 L- and 1 taeniate L-seta. Segment VII with 4 taeniate lateral setae, Segment VIII with 5 taeniate lateral setae. Anal lobe as in figure 2D, 465–480 µm long and 180–185 µm wide. Anal lobe ratio 2.51–2.67. Genital sac 285–305 µm long. GS/AL 0.61–0.64.

Adult female and larva. Unknown.

Figures

FIGURES 1 A – H. Amazonimyia gigantea Silva et Wiedenbrug sp. n., adult male. A. Head, frontal view. B. Apex of antenna. C. Thorax, lateral view. D. Wing. E. Fore tibial spur. F. Mid tibial spurs. G. Hind tibial spurs. H. Hypopygium, left side ventral view, right side dorsal view.

FIGURES 2 A – E. Amazonimyia gigantea Silva et Wiedenbrug sp. n., pupa. A. Thoracic horn and thoracic comb. B. Abdominal segments I – II, right: ventral view, left: dorsal view. C. Abdominal segment VI, right ventral view, left: dorsal view. D. Abdominal segment VII – VIII and anal lobe with male genital sac, right ventral view, left: dorsal view. E. detail of anterior shagreen on tergite IV.