Pseudochironomus surianae, Trivinho-Strixino, 2017

Trivinho-Strixino, Susana, 2017, Brazilian Pseudochironomini (Diptera: Chironomidae) Part 1. New Pseudochironomus Malloch from highlands, Zootaxa 4317 (1), pp. 134-154 : 149-152

Pseudochironomus surianae sp. n. Shimabukuro & Trivinho-Strixino

Type material. Holotype male, BRAZIL, SP, CampoS do Jordão , Galharada Stream, 3rd order, 22°41”.29’S, 45°27”.42’W, 1584 m a.S.l., 09.xi.1999. M. T. Suriano, (I1 – 36, LEIA-UFSCar). Paratype: three maleS, Same data aS holotype (I1 – 37 – 39, LEIA-UFSCar).

Etymology. Named in honour to Dr. Marcia ThaiS Suriano who collected theSe SpecimenS.

Diagnostic characters. Adult male: total length 2.89–3.40 mm; wing length 2.0 1–2.38 mm; preSence of acroStichalS; Short inferior VolSella; margin of TIX rounded and continuouS, without notch; gonoStyluS long and narrow; parS VentraliS leaf–Shaped, completely diVided.

Male (n = 4)

Total length 2.89–3.40 mm. Wing 2.01–2.38 mm long and 0.59–0.67 mm wide. Total length/wing length 1.31– 1.46. Wing length/length of profemur 2.33–2.53.

Colouration: Thorax uniformly brown, without marking ( Fig. 1 d). Abdomen with brown bandS on tergiteS. Wing hyaline with yellow VeinS. Femur yellow, tibia and tarSi dark brown

Head. AR 1.44–1.59. 13 flagellomereS. LaSt flagellomere length 612–662 µm. ClypeuS with 13–14 Setae. Palpomere –lengthS (µm) 37–59; 50–78; 116–156, 153–203, 225–291. Third palpomere with a Slight fingerlike proceSS.

Thorax ( Fig. 1 d). AcroStichalS 0–2 ( Fig. 1 d); antepronotalS 2–3, lateral, Small; dorSocentralS 11–13 in a Single row, ariSing from pale areaS; prealarS 3–4; Scutellum with 11–16 Setae, Simple to double.

Wing. VR 1.16–1.21. Brachiolum with 2–3 Setae, R with 16–21 Setae, R1 with 2–7, R4+ 5 9–14 apical Setae. Squama with 7–15 Setae.

Legs. Spur of fore tibia 44–53 µm long; SpurS of mid tibia 41–53 and 53–59 µm long; SpurS of hind tibia 41–62 µm and 44–62 µm long. Length of legS and LR proportion aS in Table 6.

Hypopygium ( Fig. 10 a). Tergite IX ( Fig. 10 c) without notch, with a rounded margin bearing 8–21 Setae. LateroSternite IX with 4–6 Setae. Phallapodeme 55–80 µm long. TranSVerSe Sternapodeme 77–89 µm long. Superior VolSella ( Fig. 10 b) 72–91 µm long curVed, apically concaVe ending aS two pointS, the longeSt with 23 µm long. Inferior VolSella Short 43–54 µm long, with microtrichia and long Setae, longeSt apical Setae 29–58 µm long. Median VolSella 12–17 µm long bearS 1 apical Setae 17–25 µm, and one Subapical Seta. Gonocoxite 143–207 µm long. GonoStyluS long 155–169 µm and narrow. HR = 0.9–1.2. ParS VentraliS completely diVided, leaf-Shaped ( Fig. 10 d), 58–78 µm long and 22–25 µm maximum wide.

Remarks. P. surianae sp. n., aS well aS P. ruah sp. n., P. jordensis sp. n. and P. mocidade sp. n. preSentS thoracic acroStichalS. HoweVer, P. surianae sp. n. differS from the other SpecieS by the Size and format of the inferior VolSella, which iS Shorter in P. surianae sp. n.; by the rounded margin of TIX, lacking a terminal notch; by the format of the gonoStyluS, which iS longer and narrower in P. surianae sp. n.; and by the leaf–Shaped format of parS VentraliS.

Ecological notes. AdultS were collected in light trapS near low-depth StreamS in mountain region of SoutheaStern Brazil. The altitude at the Sampling SiteS waS higher than 1500 m a.S.l.

Figures

FIGURE 1. Thorax and detail of the acrostichals and setal scars on scutum, lateral vieW. a. Pseudochironomus ruah sp. n.. b. Pseudochironomus jordensis sp. n.. c. Pseudochironomus mocidade sp. n.. d. Pseudochironomus surianae sp. n..

FIGURE 10. Pseudochironomus surianae sp. n. adult male. a. hypopygium, left dorsal right ventral vieW. b. superior volsella. c. posterior margin of tergite IX. d. pars ventralis.