Stenochironomus manauara Dantas, Hamada & Mendes, 2016, new species
Creators: name: Dantas, Galileu P. S.
name: Hamada, Neusa
name: Mendes, Humberto F.
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Chironomidae
Stenochironomus
Stenochironomus manauara

description: Stenochironomus manauara new species
(Figs. 24–27)
Type material. Holotype male with pupal exuviae, BRAZIL: Amazonas state, Manaus, Reserva Florestal Adolfo Ducke, Igarapé Bolivia, 02º 59' 14.5" S, 59º 56' 30.5" W, 20.vi.2009, on submerged leaf, G.P.S. Dantas, (INPA). Paratypes: 1 male with pupal and larval exuviae, as holotype collected, 26.vi.2009 (MZUSP); 1 male as holotype collected, 27.vi.2009; 2 males, one with the pupal exuviae, as holotype collected, Igarapé Acará, 02º 57' 07.4" S, 59º 57' 27.6" W, 15.iii.2009, 17.iii.2009.
Diagnostic characters. Male: scape with a circular patch on superior margin; abdomen with brown pigmentation on posterior margin of T II–IV and on posterolateral margin of T VII; two brown bands in the fore femur; anal point broad at base; superior volsella pointed at apex. Pupa: frontal apotome elongated; spur on T VIII with 4 teeth, the outer tooth quite larger than all others; row of hooklets on TII on a flap extending posteriorly. Larva: labral lamellae with two conical-shaped teeth; S1 bifid, S2 and S3 simple; micropore located posteromedially in relation to the setae submenti; ventromental plate with a concavity near mentum, with some crests near anterolateral margin.
Etymology. the name manauara is a reference to people born in the city of Manaus, where the specimens were collected. The name is to be treated as a noun in apposition.
Male (n = 5, except when otherwise stated). Total length 4.26–4.69, 4.49 mm. Wing length 1.78–2.08, 1.94 mm. Total length/ wing length 2.05–2.63, 2.33. Wing length/ length of profemur 1.41–1.52, 1.47.
General coloration greenish. Head: eyes markedly metallic when alive or in alcohol; pedicel with a circular patch on superior margin. Thorax: lateral vitta with anterior margin yellowish, with dark pigmentation restricted to a lateral stripe; postnotum with brown pigmentation near anterior margin; preepisternum with a transversal band. Legs–Anterior: femur with two brown patches, one medial and the other distal; tibia with three patches, one basal, one ⅓ from apex and the other apical; ta1-ta4 yellowish with apex light brown; ta5 yellowish.Medial and posterior legs: femur with two patches, one basal and other apical; tibia with a basal patch; ta1 - ta5 yellowish. Wing: clear, with a medial light-brownish band (hard to see when mounted in Euparal®). Abdomen: T II–IV with brown pigmentation restricted to posterior margin.
Head (Fig. 24 A). AR 1.60–2.75, 2.23. Thirteenth flagellomerum 730–1.000, 880 µm long. Temporal setae 19– 23, 21. Clypeus with 20–22, 21 setae. Tentorium, stipes and cibarial pump as in Figure 21 A. Tentorium 177–181, 179 µm long; 47–54, 50 µm wide at sieve pore; 22–28, 25 µm wide at posterior tentorial pit. Stipes 129–146, 138 µm long; 6–7, 7 µm wide. Palpomere lengths (1–5 in µm): 45–47, 46; 43–47, 45; 144–160, 150; 112–123, 120; 199–207, 201.
Thorax (Fig. 24 B). Acrostichals 11–15, 13; dorsocentrals 13–16, 15 in a single row; prealars 6–8, 7 in one or two rows. Scutellum with 19–22; 20 setae in two rows. Anterior edge of scutum angular in lateral aspect.
Wing (Fig. 24 C). VR 1.09–1.13, 1.11. Brachiolum with 2–3, 2 setae. R with 30–46, 39 setae; R1 with 32–54, 45 setae; R4+5 with 56–80, 69 setae; M with 1–4, 2 setae; RM with 0–2, 1 setae; remaining veins bare. Squama with 7 setae.
Legs. Scale of front tibia 44–52, 47 µm long, with 3–4 strong setae; spurs of middle tibia 32–39, 34 µm and 42–44, 41 µm long; spurs of hind tibia 32–40, 35 µm and 38–49, 43 µm long. Apex of fore tibia 52–65, 61 µm wide, of mid tibia 55–65, 60 µm wide, of hind tibia 61–71, 67 µm wide. Lengths (in µm) and proportions of legs as in Table 7.
fe ti ta1 ta2 ta3 ta4
p1 1263–1366, 1313 951–1267, 1135 1521–1685, 1601 759–864, 802 602–666, 625 492–562, 522 p2 992–1166, 1093 863–982, 933 620–684, 658 320–366, 339 241–267, 257 161–171, 167 p3 1159–1385, 1283 1103–1200, 1155 775–968, 877 442–505, 476 357–414, 383 218–237, 225
ta5 LR BV SV BR
p1 200–225, 212 1.28–1.68, 1.43 1.81–1.93, 1.87 1.39–1.64, 1.53 4.7–4.9, 4.8 p2 67–86, 77 0.69–0.72, 0.71 3.14–3.25, 3.19 2.99–3.20, 3.08 2.8–3.7, 3.4 p3 85–111, 101 0.70–0.81, 0.76 2.75–2.85, 2.80 2.67–2.92, 2.79 3.5–5.3, 4.6 Hypopygium (Figs, 25A, 25B, 25C). Anal point 84–95, 89 µm long; 18–23, 21 µm wide at base; µm wide at apex; 22–27, 25 µm at the midpoint; 28–30, 29 µm at ⅓ of the distance from the apex; 14–15, 15 µm at apex. Tergite IX with 41–44, 43 strong setae, caudal apex rounded to wedge-shaped in dorsal aspect. Laterosternite IX with 4–5, 4 setae. Phallapodeme 110–120, 115 µm long; transverse sternapodeme 49–57, 52 µm long. Gonocoxite 199–209, 204 µm long; inferior volsella 235–245, 238 µm long, with 4–6, 5 setae, restricted to apical ¼, apical setae stout; superior volsella pointed at apex, 59–76, 67 µm long, with 3–4 setae. Gonostylus 184–200, 193 µm long. HR 1.02–1.10, 1.06. HV 2.26–2.39, 2.32.
Pupa (n = 3 except when otherwise stated). Total length 5.52–5.58 mm.
Coloration: cephalothorax and abdomen clear. Spur on SVIII brownish, teeth with distal portion darker.
Cephalothorax (Figs. 26 A, 26B) Frontal apotome elongated (Fig. 23 A). Precorneal setae 126–159 µm long. Dorsocentrals (Dc) 118–155 µm long. Distance between Dc1 and Dc2 4 (1) µm; between Dc2 and Dc3 230 (1) µm; between Dc3 and Dc4 4 (1) µm. A laterodorsal tubercle anterior to Dc1 (Fig. 26 B). Basal ring of thoracic horn oblong (Fig. 26 C). Median suture granulose.
Abdomen (Figs. 26 D, 26E). T I bare; T II–III with large field of shagreen; T IV with a large field of shagreen, with a posterolateral dark patch on each side, posterior half of paratergites with shagreen; T V similar to T IV, except for the posterolateral patches, and the presence of small anterior median area without shagreen; T VI with an anterior field of shagreen restricted to medial region, and a posterior field extending to paratergite, the two fields are connected by a central band of fine shagreen; T VII without shagreen; T VIII with very fine shagreen restricted to anterolateral margin; anal segment with anterior pair of fine shagreen patches. TII with posterior row of hooklets, divided medially into two groups and located on a flap extending posteriorly. Abdominal setation: S I without L setae; S II–IV with 3 L setae; S V–VII with 4 LS setae; S VIII with 5 LS setae. Spur on S VIII with 4 teeth, the outer tooth quite larger than all others, 88–90 µm long (Fig. 26 F). Genital sac 358–367 µm long, overreaching the posterior margin of the anal lobe by; anal lobe 160 (1) µm long, rounded at apex, with fringe of about 50 filaments.
Fourth-instar larva (n = 1). Total length not measurable. Head capsule 0.63 mm.
Head (Fig. 27 A). Lengths of antennal segments (in µm): 72; 23; 14; 12; 4. Blade not measurable. Labrum as in Figure 27 B. Labral lamellae with two conical-shaped teeth; spicules of pecten epipharyngis simple, arranged in a row (Fig. 27 B). S1 bifid, 31 µm long; S2 simple, 35 µm long; S3 simple, not measurable. Premandible not measurable. Mandible (Fig. 27 C) 187 µm long, with 4 inner teeth; setae submenti short, drop-shaped. Maxilary palp 26 µm long, 14 µm wide. Mentum slightly concave (Fig. 27 D) 137 µm wide, number of teeth not countable; micropore located postero-medially in relation to the setae submenti; ventromental plate with a concavity near mentum, with some crests near anterolateral margin. Base of dorsolateral strip originating near the base of dorsomedian strip (Fig. 27 A). Labiohypopharynx (Fig. 27 E) with ligular lobes rounded, cleft between lobes widening posteriorly.
Abdomen. Procercus with 8 filaments; associated seta of equal size. Anal tubules not measurable. The longest anal hook 88 µm long.
Female unknown.
Systematic remarks. The adult male of S. manauara sp. nov. is similar to that of S. fittkaui Borkent and S. triannulatus. However, it can be differentiated from S. fittkaui by have pigmentation in TVII, superior volsella with a pointed apex and arched anal poitn in lateral view; from S. triannulatus is distinguished by pigmentation of the legs, while S. manauara sp. nov. has two brown bands in the fore femur, S. triannulatus has three. Recently, the immature stages of S. trianulatus were described by Angelis-Reis et al. (2013), the pattern of shagreen of T V–VI can be used to separate the pupa of this species from the pupa of S. manaura sp. nov. In addition, the spur on S VIII of the pupa has 5 teeth in S. triannulatus and the two outer teeth are elongated and of equal size, in S. manauara sp. nov. the spur has 4 teeth and the outer tooth is quite larger than all others.
Notes on biology of the species. The analyzed specimens were collected mining leaves in small black-water streams. The mined leaves were retained in submerged branches and roots, in areas with strong water flow.
description: Published as part of Dantas, Galileu P. S., Hamada, Neusa & Mendes, Humberto F., 2016, Contribution to the knowledge of Stenochironomus Kieffer (Diptera, Chironomidae) from Brazil: seven new species and description of females and immatures of some previously known species, pp. 1-47 in Zootaxa 4117 (1) on pages 33-38, DOI: 10.11646/zootaxa.4117.1.1, http://zenodo.org/record/266257