Oukuriella pesae, a new species of sponge-dwelling chironomid (Insecta: Diptera) from Amazonia, Brazil Author Fusari, Lívia Maria Author Roque, Fabio O. Author Hamada, Neusa text Zootaxa 2009 2146 61 68 journal article 10.5281/zenodo.275004 01812d3a-d029-4529-b6c9-20ab1308fea4 1175-5326 275004 Oukuriella pesae sp. n. Type material. Holotype male with pupal and larval exuviae; BRAZIL : Pará State, Rurópolis, Tambor River, Cachoeira do Grin ( 04°05’35”S , 55°00’29”W ) 28.x.2007 . L. M. Fusari, N. Hamada. Paratypes : 2 males with pupal exuviae, 1 pharate female with larval exuviae, 2 last-instar larvae; same data as holotype , except 09.x.2008 . L. M. Fusari, N. Hamada, J. O. Silva, A. M. O. Pes. Etymology. Named in honour of Dr. Ana Maria de Oliveira Pes, for her contributions to the understanding of biodiversity patterns involving aquatic insects and freshwater sponges in Brazil , and in recognition of her help with our fieldwork. Diagnosis. The male of Oukuriella pesae can be separated from other species in this genus by the following character combination: no setal tufts on anterior portions of abdominal tergites II–VII, T IX with two long projections posteriomedially; and superior volsella with slender digitus. The pupa without pedes spurii B and armament on conjunctive IV/V. The larva is distinguished by its head capsule conical, mandible strongly concave without inner teeth and mentum with a serrated median tooth and the fourth to sixth lateral teeth progressively receding to posterior. Description. Male (n = 3, except where otherwise stated). Total length 3.3–4.6 mm . Wing length 1.7–1.8 mm , width 0.5–0.6 mm . Total length/wing length ratio 1.9–2.4. Wing length/profemur length ratio, 1.5 (2). Colour: Head yellowish brown, antennae brownish. Abdomen with tergites II, VII, VIII and IX brown, remainder yellowish brown. Legs with brownish rings on basal 3/5 and apex of femur, base and apex of tibia, ta1 and ta2. FIGURE 1. Oukuriella pesae n. sp. Male: A—hypopygium in dorsal view, B—hypopygium with tergite IX removed, left: dorsal view, right: ventral view. Head ( Fig. 2 B) AR 1.31. Apical flagellomere 620 µm long. Temporals 3. Clypeus with 21–23 setae. Lengths of palpomeres 1–5 (in µm): 37–47; 35–42; 95–137 (2); 122 (1); 170 (1). Thorax ( Fig. 2 C). Without scutal tubercle. Chaetotaxy: Ac 8–12, Dc 8–9, Pa 1, Scts 7–8. Wing ( Fig. 2 A). Mostly infuscate, with contrasting light and dark markings in cells r4+5, m1+2, m3+4, an, and cu. VR 1.2–1.5. Squama bare. Brachiolum with 2 setae. R with 11–12; R1 with 12–15; R4+5 with 12 21 setae, remaining veins and cell membranes bare. Lengths (in µm) and proportions of leg segments as in Table 1 . Tibial spur lengths (in µm): fore 55 (1); middle 52–70, hind 52–70. Abdomen. Tergites without setal tufts. Hypopygium ( Figs. 1 A, 1B; 2D). T IX with two long projections posteriomedially. Phallapodeme 87.5–90 µm, transverse sternapodeme 50–55 µm long. Superior volsella 62.5–100 µm long, with 7–8 dorsal–distal setae and 7 setae near bend of upper arm, digitus slender, bare, 25–27.5 µm long. Inferior volsella 145–162.5 µm long, with 2 basal setae, 8 dorsal and 1 ventral setae. Gonocoxite 155–165 µm long. Gonostylus slender, 195–200 µm long. HR 0.80–0.82. HV 1.64–2.30. TABLE 1. Lengths (in μm) and proportions of legs of Oukuriella pesae n. sp. , male (n = 3, unless otherwise stated). fe ti ta1 ta2 ta3 p1 1280 (1) 620(1) - - - p2 1160–1200(3) 720 (2) 600–720(2) 300 (1) 220 (1) p3 1160–1320 (3) 800–820 (3) 580–640 (2) 460 (1) 340 (1) continued. ta4 ta5 LR BV SV p1 - - - - 3.38 (1) p2 140 (1) 80 (1) 0.83 (1) 3.40 (1) 3.20 (1) p3 220 (1) 120 (1) 0.72–0.80 (2) 2.40 (1) 3.31 (1) Female (n = 1, pharate) Similar to male, except as follows. Total length about 6.4 mm . Colour: similar to male. Head: AR = 0.29. Flagellomere lengths (in µm): 175, 125, 130, 100, 152. Clypeus with 11 setae. Palpomere lengths (μm): 50, 45, 120, 152, 162. Thorax: Without scutal tubercle. Chaetotaxy: Ac 12, Dc 9, Scts 8. Wing: not observable on pharate specimen. Legs: not observable on pharate specimen. Genitalia: Seminal capsule ovoid, about 85 µm long. Spermathecal duct straight. Notum 187 µm. Gonocoxapodeme 227 µm. Dorsomesal lobe, ventrolateral lobe and apodeme lobe as in Figure 3 A. Gonocoxite IX 97 µm long, with 4 setae. Tergite IX with 31 setae. Cerci about 157 µm long. Pupa (n = 3, except where otherwise stated) Exuviae yellowish brown. Cephalothorax length 1.34–1.48 mm , abdomen length 3.78 mm . Cephalothorax. Frontal apotome with low and rounded cephalic tubercles. Dorsal region granular. Two lateral antepronotals, two precorneals, and two separated pairs of dorsocentrals, distances Dc1–Dc2, Dc2–Dc3, Dc3–Dc4 (in µm): 17(1), 190(1), 27(1). Basal ring oval. Prealar tubercle absent. Abdomen ( Fig. 3 B). Tergites II–VI with shagreen; T V, VI with extensive central shagreen; T I, VII and VIII without shagreen. Hook row continuous, occupying 2/3 width of segment. Pedes spurii B absent; vortex present on segment IV. All conjunctives unarmed. Anal comb with several small teeth on margin and ventral surface ( Fig. 3 C). Segments II–IV with 1 L seta, V–VIII with 4 lateral taeniae. Anal lobe well developed, with approximately 160 long taeniae ( Fig. 3 B). 4th -instar larva (n = 4, including 2 exuviae, unless otherwise stated) Head ( Fig. 2 E, 2F). Width 230–290(3) µm, length 470– 500(3) µm. IC = 0.49–0.58(3) Antenna 28–55 µm long, with 5 segments; AR = 1.2; ring organ near antennal base; blade longer than flagellum, accessory blade short; Lauterborn organs on apex of segment 2 ( Fig. 3 F). Premandible distally bifid, with brush. Pecten epipharyngis with 3 scales. Mandible strongly concave, 65–90 µm long, without inner teeth, apex black; seta subdentalis slender ( Fig. 3 E). Mentum 47–62 µm with a light-coloured, serrated median tooth and 6 pairs of lateral teeth, the first smaller than the remaining lateral teeth, the first and second light-coloured and nearly level with the median tooth, the fourth to sixth lateral teeth dark and progressively receding to posterior; ventromental plates 42–55 µm wide, medially separated by no more than width of median tooth ( Fig. 3 D). Setae submenti simple, long and slender. Abdomen 6.7–7.0(2) mm long, reddish, with short posterior parapods carrying strong claws. Anal tubules 25(2) µm long, without constriction. Procerci with 6 coarse anal setae ( Fig. 2 G).