Podonomus pepinellii, Roque & Trivinho-Strixino, 2004

Roque, Fabio De Oliveira & Trivinho-Strixino, Susana, 2004, Podonomus pepinellii n. sp., first record of the genus and subfamily from Brazil (Diptera: Chironomidae: Podonominae), Zootaxa 689 (1), pp. 1-7 : 2-5

Podonomus pepinellii sp. n.

Type material. Holotype: male imago with associated pupal skin (slide­mounted in Euparal). Brazil, Minas Gerais, Camanducaia, first­order stream (22°53'S, 46°02'W) at 1853 m elevation, 23.v.2004, leg. M. Pepinelli and N. Hamada; deposited in the collection of the Museu de Zoologia da Universidade de São Paulo, São Paulo, Brazil ( MZUSP).

Adult male (n = 1) ( Figs. 1–7 )

Body length 3.36 mm; wing 1.64 mm long, 0.48 mm wide. Head brown; thorax yellowish brown, with mesonotum and episternum dark brown; wings grayish; legs and abdominal tergites brownish.

Head. Temporal setae 16, clypeals 4. Antenna with 14 flagellomeres ( Fig. 1 ), Fm14 52 µm, Fm13 165 µm, Fm1–12 697 µm long; AR = 0.31; apical flagellomeres as in Fig. 2 . Palp as in Fig. 3 ; palpomere lengths 2–5: 32 µm, 116 µm, 84 µm, 80 µm.

Thorax. Antepronotals 6; acrostichals about 40, biserial; dorsocentral (Dc), humeral (H), prescutellar (Pr), and prealar (Pa) setation as in Fig. 4 ; scutellars 6; postnotals absent.

Wing ( Fig. 5 ). Membrane without setae, with microtrichia. VR 0.92. Brachiolum with 5 setae, R with 27, squama with 5. Costa extended 120 µm beyond apex of R 4+5.

Leg lengths and proportions in Table 1 . Spur ( Fig. 6 ) lengths: PI 50; PII 38, 42; PIII 40, 86 µm. Comb of hind tibia with 11 spiniform setae.

Hypopygium ( Fig. 7 ). Gonocoxite length 150 µm, gonostylus 62 µm; HV 2.4. Gonostylus simple, not differentiated into lobes; megaseta of apical lobe 20 µm long; P, x and y setae present, but not conspicuous. Genitalic apodemes as in Fig. 7 ; phallapodemes in longitudinal, mesal position, with distal portions protruded outside the hypopygium.

Pupa (n = 1) ( Figs. 8–11 )

Exuviae pale, mesonotum with median­lateral and posterior brownish spots. Total length 3.6 mm. Frontal apotome and prefrons as in Fig. 8 . Thoracic horn as in Fig. 9 . Plastron plate of thoracic horn large, rounded, triangular, 240 µm long by 208 µm greatest width, with closely set and densely arranged pores. External membrane of thoracic horn with elongate, sharply pointed polygonal mesh. Respiratory atrium opening to plastron through 4 aeropyles; 3 short precorneals. Thoracic setation as in Fig. 10 ; distance from Dc1–3 to Dc4 about 220 µm. Posterior angles of abdominal segments III–VIII protracted into large transverse processes ending in sharp, straight points. Abdominal chaetotaxy as in Fig. 11 (sternites I and II are incomplete). Abdominal segments VIII and IX with 6 and 5 macrosetae, respectively; anal spur reduced.

Etymology. Named in honour of Mateus Pepinelli, our friend, who has contributed much to our studies of the Chironomidae and who collected the holotype.

Figures

FIGURES 1–7. Podonomus pepinellii sp. n., male adult. 1. antenna. 2. apical flagellomeres. 3. palpomeres II–V. 4. lateral view of scutum. 5. wing, Dc — dorsocentrals, H — humerals, Prs — prescutellars, and Pa — prealars. 6. tibial spurs. 7. hypopygium, left: ventral and internal views, right: dorsal view.

FIGURES 8–11. Podonomus pepinellii sp. n., pupa. 8. frontal apotome. 9. thoracic horn; A. pores, B. aeropyles, and C. external membrane of thoracic horn. 10. thorax. 11. abdominal segments, left: ventral view (SI and SII not preserved), right: dorsal view.