Saetherolabis iperuype, Andersen, Trond, Mendes, Humberto F. & Pinho, Luiz C., 2012

Andersen, Trond, Mendes, Humberto F. & Pinho, Luiz C., 2012, Two new species of Saetherolabis Andersen et Mendes, 2007 from Brazil (Diptera: Chironomidae, Orthocladiinae), Zootaxa 3300, pp. 62-68 : 63-65

Saetherolabis iperuype sp. n.

( Figs 1–6 )

Type Material: Holotype male: BRAZIL, São Paulo State, Peruibe, Estação Ecológica Juréia-Itatins, 24°31'06''S 47°12'06''W, 06.v.2002, Malaise trap (Bosque 6), N.W. Perioto et al. ( PEJU 08: BIOTA-FAPESP) ( MZUSP). Paratypes, 2 males, as holotype ( MZUSP, ZMBN), 1 male, as holotype except 03.v.2002, ( PEJU 02) ( MZUSP).

Etymology: From the native Brazilian language Tupi, iperu and ype, ‘shark’ and ‘river, sea’, meaning river filled with sharks. The name is an allusion for the type locality and is to be treated as a noun in apposition.

Diagnostic characters: The species can be separated from S. pectinata by having a slightly higher AR (1.16– 1.26 compared to 0.93–0.98) and HR (1.58–1.86 compared to 1.12–1.37), by having a well developed, rounded superior volsella and on the oral branch of inferior volsella which is digitiform, straight and almost perpendicular to caudal branch; from S. siriype on the arched transverse sternapodeme with oral projections barely indicated and on the shape of the inferior and superior volsellae.

Description: Male (n = 3–4). Total length 1.50–1.58 mm. Wing length 838–912 μm. Total length / wing length 1.65–1.89. Wing length / length of profemur 2.91–3.09.

Coloration. Head, pedicel, thorax and coxae dark brown; flagellum of antenna, palpomeres, legs (trochanter to tarsomere 5) light brown; abdominal segments I–III, VI–VII and hypopygium light brown, segments IV–V dark brown.

Head. AR 1.16–1.26. Antenna with 13 flagellomeres, ultimate flagellomere 295–313 μm long. Temporal setae 4–6 including 2 inner verticals and 2–4 outer verticals. Clypeus with 4–7, 5 setae. Cibarial pump, tentorium and stipes as in Figure 1 . Tentorium 73–95 μm long, 14–16 μm wide at sieve pore. Stipes 66–82 μm long. Palp segment lengths / widths (in μm): 14–16 / 14–16, 20–23 / 14–16, 45–48 / 14–16, 52–61 / 10–12, 68–93 / 7–9. Third palpomere with 5–6 sensilla clavata in subapical sensillum coeloconicum ( Fig. 2 ), longest 9–11 μm long.

Thorax ( Fig. 3 ). Antepronotum with 2–4 setae. Dorsocentrals 10, acrostichals 2 scalpellate in mid scutum, prealars 3–4. Scutellum with 4 setae.

Wing ( Fig. 4 ). VR 1.53–1.66. Costal extension 29–34 μm long, with false vein nearly reaching wing tip. Brachiolum with 1 seta, remaining veins and cells bare.

Legs. Spur of fore tibia 38–45 μm long; mid tibia with only one spur, 14–20 μm long; spurs of hind tibia 39–45 μm and 18–23 μm long. Width at apex of fore tibia 17–19 μm, of mid tibia 20 μm, of hind tibia 27–34 μm. Comb with 11–13 setae, longest 29–36 μm long, shortest 16–23 μm long. With row of spine-like setae on all tarsomeres of fore-, mid- and hind legs, particularly distinct on ta1; setae on ta1 of fore leg 20–29 μm long. Mid- and hind leg with stout, subapical seta on all tarsomeres; seta on tarsomeres 1–4 of mid leg 20–23, 16–18, 16–17 and 16 μm long; on tarsomeres 1–4 of hind leg 19–21, 18–19, 16–17, 14–15 μm long. Lengths and proportions of legs as in Table 1.

Hypopygium ( Figs 5–6 ). Tergite IX with 3–7, 5 strong setae on each side of anal point; laterosternite IX with 4–5, 5 setae. Anal point 40–45, 43 μm long; 9–14, 12 μm wide at base; 6–7, 6 μm wide at apex; without microtrichia. Phallapodeme 54–66, 59 μm long; transverse sternapodeme 50–57, 55 μm long, curved, with oral projections barely indicated. Virga 9–15, 12 μm long. Gonocoxite 107–122, 113 μm long. Inferior volsella deeply split; oral branch digitiform, straight, almost perpendicular to caudal branch, 25–27, 26 μm long, 9–12, 10 μm wide at base; caudal branch broadly rounded, straight, 17–19, 18 μm long, 14–18, 15 μm wide at base. Superior volsella well developed, broadly rounded, with strong setae. Gonostylus 61–70, 66 μm long, without crista dorsalis; megaseta 8 μm long. HR 1.58–1.86, 1.72; HV 2.14–2.58.

Distribution and ecology: This species is known from four specimens collected in Malaise traps in Peruíbe, São Paulo State, Brazil. This nature reserve covers an area of about 80.000 ha in the southernmost coastal parts of São Paulo State and the vegetation consists of both primary and secondary forest, mainly mangrove and different types of coastal rainforest.

Figures

FIGURES 1 – 6. Saetherolabis iperuype sp. n., male. 1 – tentorium, stipes, and cibarial pump; 2 – palp; 3 – thorax; 4 – wing; 5 – hypopygium, dorsal aspect; 6 – hypopygium with anal point and tergite IX removed, dorsal aspect to the left and ventral aspect to the right.