Ann. Limnol. - Int. J. Lim. 49 (2013) 255–264 Available online at: Ó EDP Sciences, 2013 www.limnology-journal.org DOI: 10.1051/limn/2013057 New species of Nanocladius Kieffer, 1913 (Diptera: Chironomidae: Orthocladiinae) from Neotropical region Sofia Wiedenbrug1* and Fabio Laurindo da Silva2 1 Museum of Zoology, University of Sa˜ o Paulo, Av. Nazare´ , 481, 04263-000, Sa˜ o Paulo, SP, Brazil 2 Laboratory of Aquatic Entomology, Department of Hydrobiology, Federal University of Sa˜ o Carlos, P.O. Box 676, 13565-905, Sa˜ o Carlos, SP, Brazil Received 5 June 2013; Accepted 11 September 2013 Abstract – The genus Nanocladius Kieffer, 1913 (Diptera: Chironomidae: Orthocladiinae) has been frequently found in aquatic habitats of the Neotropical region. However, until now only one species was described living symphoretically on Ephemeroptera and no free-living species has been cited or formally described from the region. In the present study, two new species of Nanocladius are described and figured as male, pupa and larva: N. communis and N. longispicula. The specimens were collected from different streams in Brazil and are the first recorded species of the genus to the country. Key words: Brazil / Chironomidae / Nanocladius / immature stages / taxonomy Introduction The Holarctic species of the genus were described and revised by several authors (e.g., Sæther, 1977; Non-biting midges of the genus Nanocladius are Niitsuma, 1991; Harrison, 1994; Fu and Wang, 2009), minute dipterans with worldwide distribution. Sæther but a comprehensive revision of the genus is still not (1977) first revised the genus and defined two subgenus: available. In the present study, two new species of Nanocladius str. usually with free-living larvae in lotic Nanocladius from Brazil are described and figured as and lentic habitats (Cranston et al., 1983), and N. Pleco- adult, pupa and larva. pteracoluthus, whose immatures are found living symphor- etically on the larvae of Plecoptera, Megaloptera and Ephemeroptera (e.g., Steffan, 1965; Epler, 1986; Hayashi, 1998). Prior to the present study Nanocladius comprised Materials and Methods 34 species, of which only N. (Plecopteracoluthus) bubra- chiatus Epler occurs in the Neotropical region (Ashe Adults, pharate adults and pupal exuviae were col- and O’Connor, 2012). No species was formally described lected with drift nets. Living larvae were collected from the Australian region, although several morphotypes with hand nets and isolated in small boxes (1 cmr1 cm) are known (e.g., Cranston, 1996). half filled with stream water. Neither substratum nor food In Brazil, numerous ecological studies have recorded was given, except for some detritus carried over with the the larvae of Nanocladius, living symphoretically on water. The boxes were checked twice a day for the emerged other insects (Callisto and Goulart, 2000; Dorville´ et al., specimens. Larval skins, pupal exuviae and adults were 2000) or free-living on stones, litter, sediments and aquatic preserved in 96% ethanol. The specimens examined were macrophytes in reservoirs and rivers (e.g., Sanseverino and slide-mounted in Euparal. Nessimian, 1998, 2001; Callisto et al., 2002; Henriques- Morphological terminology and abbreviations follow Oliveira et al., 2003; Suriano and Fonseca-Gessner, Sæther (1980). Data on larvae represent the 4th instar. 2004; Janke and Trivinho-Strixino, 2007). In addition, Measurement methods followed Epler (1988). Mensural several morphotypes were described (Ospina-Torres, 1992; data are given as ranges, followed by the number of Wiedenbrug, 2000). Although the larvae of Nanocladius observed specimens in parenthesis if different from the are common in the benthos fauna, until the present study number (n) stated at the beginning of the description. no species was described or cited from Brazil. Seta counts are given as the ranges only. The holotypes and paratypes are deposited in the Museum of Zoology *Corresponding author: sofi[email protected] of the University of Sa˜ o Paulo (MZUSP), Brazil. Article published by EDP Sciences 256 S. Wiedenbrug and F.L. da Silva: Ann. Limnol. - Int. J. Lim. 49 (2013) 255–264 Fig. 1–4. Nanocladius (N.) communis sp. n., male. 1 head, 2 wing, 3 hypopygium (dorsal view), 4 hypopygium (ventral view). Taxonomy Diagnostic characters. The male of N. N. communis can be separated from other species of the genus by the Nanocladius (N.) communis sp. n. (Figs. 1–15) following character combination: apical setae on antenna Nanocladius (N.) spec. 1 Wiedenbrug (2000) brown, straight and much shorter than apical flagellomere, Type material. Holotype male with pupal and AR 0.6, tergites with four to six setae uniserial distri- larval exuviae, Brazil, Sa˜ o Paulo, Sa˜ o Carlos, Fazenda buted, phallapodeme without oral projections, inferior Canchin, 21x57.996'S, 47x50.604'W, 858 m a.s.l., volsella triangular, anal point narrow, short, basally with 19.v.2011, S. Wiedenbrug. Paratypes: one male with pupal microtrichia. The pupa can be distinguished due to the exuviae same data as holotype except for Ubatuba, stream digitiform thoracic horn with spines, pedes spurii B con- near Ruı´ nas da Lagoinha, 23x30.468'S, 45x11.923'W, 0 m spicuous, hook row on protuberance, posterior lateral seta a.s.l., xii.2000. Four pupal exuviae as previous except taeniate on segment VI and usually on V, tergites IV–VI for Serta˜ o da Quina, Cachoeira da Renata, bridge, with median spine-patches and posterior row of spines, 23x31.231'S, 45x14.625'W, 33 m a.s.l., 2.v.2007, two on male pupa posterior ventral surface of anal lobe with of them in the same slide as the paratypes of N. (N.) shagreen points. The following characters are diagnostic longispicula sp. n. One pharate male same data as before for the larva: AR 1.14, ventromental plates very long but 23x30.789'S, 45x14.442'W, 61 m a.s.l., 29.xii.2010. rounded at caudal apex, with a ridge parallel to the anterior Additional material examined. Five pupal exuviae, margin, premandible faint bifid, mentum with lateral teeth Brazil, Rio Grande do Sul, Taquara, Arroio do Mineiro, well defined, claws of anterior parapods serrated. 15.xi.1994, S. Wiedenbrug. One pupal exuviae, same Etymology. Derived from the Latin communis, meaning data as before but, Sa˜ o Francisco de Paula, Arroio dos common, and refers to a customary occurrence of this Carros. species in the benthic fauna of the sampled streams. S. Wiedenbrug and F.L. da Silva: Ann. Limnol. - Int. J. Lim. 49 (2013) 255–264 257 Fig. 5–11. Nanocladius (N.) communis sp. n., pupa. 5 frontal apotome, 6 thorax, 7 detail of thoracic horn and precorneals, 8 abdomen segments I–VIII (dorsal view) and anal lobe (left, dorsal view right, ventral view), 9 abdomen segments III–VIII (ventral view), 10 detail of hook row and 11 detail of anal lobe (ventral view, male). Description at largest part, bearing six to seven setae. Cibarial pump with anterior margin straight, 88–113 mm long. Palpomere Adult male (n=2 unless otherwise stated) lengths 1–5 (in mm): 23–25; 33; 53–58; 63–70; 120 (1). Size. Total length 1.10–1.18 mm. Wing length 0.89– Antenna with 13 flagellomeres, flagellum 570–580 mm 0.90 mm. Total length/wing length 1.57–1.70. Wing long, apex slightly expanded, with short sensilla chaetica, length/length of profemur 2.31 (1). setae on apex much shorter than last flagellomere, straight Coloration. Head brown; maxillary palp pale brown. and light brown. Diameter of pedicel 80–100 (2) mm. AR Thorax brown with mesonotum dorsally dark brown; 0.63–0.66. antepronotum pale brown. Wing membrane transparent Thorax. Antepronotum with one lateral seta. Mid without spots and veins pale brown. Legs pale brown. scutum with a scar, acrostichals not visible. Dorsocentrals Posterior margin of TIV–TV, anterior margin of TVI, 4–5, regularly uniserial. Prealars 1. Anapleural suture ratio TVIII and TIX brown, other tergites light brown. 0.71. Scutellum with two setae. Anepisternals, preepister- Gonocoxite and gonostylus light brown (1). nals and postnotals absent. Head (Fig. 1). Eyes hairy. Temporal setae 1. Tentorium Wing (Fig. 2). Width 0.31–0.32 mm. Costa 0.82–0.85 mm 120–125 mm long, stipes not measurable. Small frontal long, produced beyond R4 + 5, ending very slightly be- tubercles present. Clypeus 38–40 mm long, 68 mm wide yond the tip of M3 + 4.R2 + 3 not observed. VR 1.14–1.18. 258 S. Wiedenbrug and F.L. da Silva: Ann. Limnol. - Int. J. Lim. 49 (2013) 255–264 Table 1. Lengths (in mm) and proportions of leg segments in Nanocladius communis n. sp., adult male. Fe Ti ta1 ta2 ta3 p1 300 (1) 380 (1) 250 (1) 210 (1) 140 (1) p2 290–310 290–300 150 (1) 90 (1) 60 (1) p3 310–340 390 200–210 120 80 ta4 ta5 LR BV SV p1 70 (1) 50 (1) 0.66 (1) 1.98 (1) 2.72 (1) p2 20 (1) 20 (1) 0.52 (1) 3.95 (1) 4.00 (1) p3 50 40 0.51–0.54 3.14–3.21 3.33–3.65 Pupa (n=6 unless otherwise stated) Size. Abdomen 0.85–0.98 (5) mm long Coloration. Exuviae and thoracic horn light brown. Cephalothorax (Figs. 5–7). Frontal apotome granulose, frontal setae 207 mm long (1), on the small tubercles on the frontal apotome. Thorax smooth, slightly granulated on circular area ventral to the thoracic horn. Ocular field with two postorbital setae. Antepronotum with two median setae and one lateral seta. Three precorneal setae, the longest 0.56 (1). Four dorsocentrals, Dc2 and Dc3 near each other. Prealar absent. Wing sheath smooth, 350– 620 mm long. Thoracic horn digitiform with scattered, pale spinules, 85–125 mm long and 10 mm (3) wide.