Endotribelos sublettei, Trivinho-Strixino, Susana & Pepinelli, Mateus, 2015

Trivinho-Strixino, Susana & Pepinelli, Mateus, 2015, A systematic study on Endotribelos Grodhaus (Diptera: Chironomidae) from Brazil including DNA barcoding to link males and females, Zootaxa 3936 (1), pp. 1-41 : 29-30

Endotribelos sublettei sp. n.

( Figs 16–17 )

Type material. Holotype: Male with pupal exuviae, slide mounted in Euparal, Brazil, São Carlos, SP, Córrego Vintenove, 5.v.2012, S. Trivinho-Strixino (E3-34, LEIA-UFSCar), barcode (BNB2-00736/ST011). Paratypes: 1 male as holotype except (E3-36, LEIA-UFSCar), 3.v.2012; 1 male with pupal exuviae, as holotype except Represa do Fazzari, 01.iv.2014 (E3-37, LEIA-UFSCar); 1 male with pupal and larva exuviae in two slides, as holotype except Córrego do Fazzari, 18.iv.2014 (E3-38, E3-39 LEIA-UFSCar); 1 male with pupal and larval exuviae, Córrego do Fazzari, 22.iv.2014 (E3-41, LEIA-UFSCar); 1 female with pupal exuviae as holotype except (E1-35, LEIA-UFSCar) and barcode (BNB2-00732/ST007); 1 female with pupal and larval exuviae as holotype except Córrego do Fazzari, 18.iv.2014, (E1-40, LEIA-UFSCar); 1 4th instar larva slide mounted in Hoyer medium, as holotype except Córrego do Fazzari, 18.vii.2011, (E1-42, LEIA-UFSCar).

Etymology. Named in honor of Dr. James E. Sublette who immensely contributed to the studies of taxonomy of Chironomidae .

Diagnostic characters. Endotribelos sublettei sp. n. differs from all other species of the genus by the combination of the following characters. Adult male: thorax yellowish with brown mesonotal stripes; postnotum brown; anal point thin, base as broad as apex and as long as inferior volsella. Pupa: abdominal posterolateral spur simple; intersegmental membrane III/IV and IV/V with two patches of short shagreen. Larva: mentum with fifteen teeth; median tooth sutured slightly shorter than first laterals; mandible with three inner teeth.

Male (n=5). Size.Total length 3.7–3. 9 mm. Wing 1.8–2.8 mm long and 0.5 mm wide.

Coloration. Head yellowish; palpomere and antenna brown. Thorax scutum yellowish with dark brown middle line and mesonotal stripes; pleura with brownish band; postnotum brown ( Figs14 a, b). Abdomen yellowish with brown bands as fig. 16c. Legs brown, mid and hind legs pale brown.

Head. Temporal setae 13–16. Clypeus with 11–14 setae. Antenna 1.00– 1.18 mm long; AR 1.32–1.47. Palpomere 2–5 lengths: 44-50, 125–156, 87–113, 125–132 µm.

Thorax. Ac 13–16; Dc 13–17; Pa 4–5; Scts 10–13 coarse, in a straight posterior row and with 5 finer setae on anterior face.

Wings. VR 1.16–1.22. Brachiolum with two setae. R with 23–30, R 1 27–31 and R4+5 34 –44 setae, remaining veins bare. Squama with 8–9 setae.

Legs. Scale on fore tibia 41–51 µm long, with a short black spine at apex ( Fig. 16 d). Tibial combs of mid and hind legs partly fused; mid tibial spur on posterior comb 58–68 µm long; hind tibial spur anterior 31–42 µm, posterior 66–75 µm long. Lengths and proportions as in Table 11 .

Hypopygium ( Fig. 16 e). Anal point 59–64 µm long; base as broad as apex. Tergite IX with 13–20 strong setae. Laterosternite IX with two setae. Transverse sternapodeme 107 µm long. Phallapodeme 103 µm long. Gonocoxite 100–141 µm long. Superior volsella 61–80 µm long, broad basally and strongly curved distally, with two long basal setae and one long sub-apical seta, near 1/3of apex ( Fig. 16 f). Gonostylus 175–200 µm long. HR 0.54–0.71. HV 1.7-2.27.

Female (n=2). Dimension and coloration. Length 4.1–4.3 mm. Wing length 1.9–2.1 mm. Coloration as male.

Head. Temporal setae 9–12. Clypeus with 17–18 setae. Antenna 0.620. 64 mm long; AR 0.38–0.39. Palpomere 2–5 lengths: 62, 144, 81, 156 µm.

Thorax. Ac 13; Dc 19–21; Pa 5; Scts 13–14 coarse and 5–7 finer setae on anterior face. Scutal tubercle absent.

Wings. VR 1.16–1.23. Brachiolum with two setae. R with 29–31, R1 33, R4+5 75–86, M 7 –12 setae, remaining veins bare. Squama with 10 setae.

Legs. Scale on front tibia 44–47 µm long, with a short spine at apex. Tibial combs of mid and hind legs partly fused; mid tibial spur 65–68 µm long; hind tibial spur anterior 33–40 µm, posterior 75–77 µm long. Lengths and proportions as in Table 12 .

Genitalia. Setal patches on sternite VIII with 16−20 setae. GC IX with 2–5 setae. Segment X with 7–8 setae. Seminal capsule 75–87 µm long. Notum 129−140 µm long, rami 75 µm. Gonoconapodeme semicurved 162–237 µm long. Cercus 116 µm long.

Pupa (n=6, 4 males, 2 females). Abdomen 3.4–4.2 mm long. Wing sheath 1.2–1.4 mm long. Exuviae coloration greyish; intersegment dark gray.

Cephalothorax. Cephalic tubercles 50–69 µm long, conical, apically with several pointed spinules; frontal setae 147–187 µm long ( Fig. 17 a). Antepronotal seta 1, precorneal setae 2, dorsocentral setae 4. Distance between Dc1 and Dc 2 16–31 µm, between Dc2 and Dc3 181–200 µm, between Dc3 and Dc 4 15–25 µm.

Abdomen. Tergite I bare, II with fine shagreen, III–VI covered with shagreen, spines near central part of anterior margin stronger, VII and VIII bare. Paratergites V and VI with spines posteriorly. Conjuntives III/IV and IV/V with two large patches of anteriorly directed short spines. Hook row continuous with near 73−89 curved spines occupying near 2/3 width of segment II. Pedes spurii A and B present. Spur on segment VIII simple ( Fig. 17 b). Abdominal lateral setation: segment II–IV with three L setae, V–VI with three taeniate setae, VII–VIII with four taeniate setae. Anal lobes with 66−77 taeniate fringe setae on each side.

4th instar larva (n=4). Head capsule yellowish, tips of mandibles, mentum and occipital ring blackish. Larvae bright red when alive.

Head. Dorsal head length 406–450 µm; ventral 194−212 µm; width 312−343 µm; IC 0.76. Antennal basal segment 32–34 µm long. AR 1.03–1.13; antennal blade as long as antennal flagellum ( Fig. 17 e). Clypeus 28–34 µm long ( Fig. 17 d). Pecten epipharyngis formed by three toothed plates ( Fig. 17 c). Premandible 63–67 µm long with two major and one minor teeth; brush well developed ( Fig. 17 f). Mandible 107–117 µm long, with small dorsal tooth, apical and three inner teeth dark; seta subdentalis slender, 31–34 µm long ( Fig. 17 g). Mentum 86–94 µm wide, with fifteen dark teeth; median tooth sutured and slightly shorter than first laterals; 2nd lateral teeth smaller than 3rd lateral teeth ( Fig. 17 h). Ventromental plate 102– 107 µm width, with very distinct striations; distance between ventramental plates 23–26 µm.

Abdomem. Procercus short as long as wide, with 7 anal setae. Anal tubules 151–210 with median constriction. Posterior parapods with brownish claws.

Figures

FIGURE 14. Endotribelos semibruneus sp. n. Male. a. Thorax, dorsal view. b. Thorax, lateral view. c. Fore tibial spine. d. Hypopygium, left dorsal view, right dorsal view, tergite IX removed and with detail of left superior volsella. e. Superior volsella.

FIGURE 16. Endotribelos sublettei sp. n. Male. a. Thorax, dorsal view. b. Thorax, lateral view. c. Abdmen dorsal view. d. Fore tibial spine. e. Hypopygium, left dorsal view, right dorsal view, tergite IX removed and with detail of left superior volsella. f. Superior volsella.

FIGURE 17. Endotribelos sublettei sp. n. Pupa a. Cephalic tubercles. b. Spur. Larva. c. Pecten epipharyngis. d. Dorsal sclerites of head. e. Antenna. f. Premandible. g. Mandible. h. Mentum and ventromental plate.

Tables

TABLE 11. Lengths (in Μm) and proportions of legs of Endotribelos sublettei sp. n. male.

fe	ti	ta1	ta2	ta3
p1 1150–1250	875–976	1162–1556	675–936	594–750
p2 1131–1231	900–1006	556–613	312–389	244–281
p3 1125–1219	981–1094	781–881	462–519	387–450

TABLE 12. Lengths (in Μm) and proportions of legs of Endotribelos sublettei sp. n. female.

	fe	ti	ta1	ta2	ta3
p1	1275–1331	1025	1406–1500	887	675–681
p2	1225–1288	1025–1050	643	375	281
p3	1213–1262	1031–1150	863–937	519–525	437–450