Labrundinia unicolor Silva

Silva, Fabio Laurindo Da, Fonseca-Gessner, Alaide Aparecida & Ekrem, Torbjørn, 2014, A taxonomic revision of genus Labrundinia Fittkau, 1962 (Diptera: Chironomidae: Tanypodinae), Zootaxa 3769 (1), pp. 1-185 : 171-177

Labrundinia unicolor Silva sp. n.

( Figs 83–85)

Labrundinia sp. 3 Silva et al. 2013: 600 ( DNA barcodes).

Material examined. Type material: Holotype male with pupal and larval exuviae, Brazil: São Paulo, São Carlos, Fazzari resevoir, 21.v. 2007, F. L. Silva ( MZUSP). 13 Paratypes: 1 male with pupal and larval exuviae same data as holotype except for Ecological Park, 23.v. 2008 ( NTNU); 2 males with pupal and larval exuviae same data as holotype except for Canchin reservoir, 2.ii. 2009 ( NTNU); 2 males and 1 female with pupal exuviae as previous except for Canchin reservoir, 2.ii. 2009 ( NTNU); 1 male with pupal and larval exuviae same data as holotype except for Ribeirão Preto, Monte Alegre Lake, 7.iv. 1998, H. F. Mendes ( NTNU); 1 male with pupal and larval exuviae as previous except for Ribeirão Preto, Monte Alegre Lake, 22.v. 2000, H. F. Mendes ( NTNU); 1 pupa with larval exuviae and 3 larvae as previous except for 12.vii. 1997 ( NTNU); 1 male with pupal and larval exuviae same data as holotype except for Pirassununga, CEPTA, 10.ix. 2010 ( NTNU). 1 male with pupal exuviae as previous ( NTNU).

Etymology. Derived from the Latin unicolor , meaning ‘of a single colour’, and refers to the uniform brown abdomen of the new species.

Diagnostic characters. Labrundinia unicolor sp. n. differs from other Labrundinia species by the combination of the following characters. Adult male: tentorium 90–126 Μm long; R 2 + 3 absent; abdomen completely brown; hypopygium brown, sternapodeme with distinct anterior process. Pupa: thoracic horn semi-globose, external margin convoluted, preapical indentation moderately deep. Larva: surface of head capsule smooth, lateroventral and posteroventral spine groups absent; paraligula multi-toothed, with 4 teeth; subbasal seta of posterior parapod serrated; bifid claw with V-shaped lower indentation.

Description. Adult male (n = 11)

Size. Total length 1.9–2.4 ( 9) mm. Wing length 1.1–1.4 mm. Total length/wing length 1.51–1.96 ( 9). Wing length/ profemur length 2.05–3.30.

Coloration. Head brown with dark brown occipital margin; pedicel and antenna brown; maxillary palp pale brown. Thorax pale brown with dark scutum; antepronotum brown; supraalar callus brown. Wing membrane transparent without any marking. Legs brown. Abdomen including hypopygium brown ( Fig. 83 L).

Head ( Figs 83 A–E). Temporal setae 11–15, uniserial ( Fig. 83 B). Eye ratio 1.04–1.38 ( 8). Tentorium ( Fig. 83 C) 90–126 ( 8) Μm long. Clypeus 78–107 Μm long, 46–70 Μm wide at largest part, bearing 14–22 setae. Cibarial pump 153–204 Μm long ( Fig. 83 D), with anterior margin concave. Lengths of palpomeres 1–5 (in Μm): 29–43 ( 6); 38–59 ( 6); 85–117 ( 6); 111–157 ( 3); 207–286 ( 2). Antennal flagellum 740–860 ( 6) Μm long, diameter of pedicel 116–142 ( 4) Μm, apical setae single ( Fig. 83 E), AR 1.35–1.54 ( 6).

Thorax. Antepronotum with 2–4 ( 7) lateral setae. Acrostichals 42–46 ( 7), biserial, diverging evenly posteriorly, starting close to antepronotum and almost reaching scutellum; dorsocentrals 24–36 ( 9), irregularly uniserial; prealars 9–14 ( 10); supraalars 2–3. Anapleural suture ratio 0.33–0.49 ( 7). Scutellum with transverse row of 8–10 setae and group of numerous fine anterior setae.

Wing ( Fig. 83 F). Width 0.3–0.4 mm. Costa 0.9–1.2 mm long. R 2 + 3 absent. VR 0.68–0.78. WW 0.29–0.32. Brachiolum with 2 setae. Squama setiferous.

Legs ( Figs 83 G–K). Fore leg: width at apex of tibia 30–39 Μm ( Fig. 83 G), tibia with single, apical and pectinate spur 13–20 Μm long ( Fig. 83 H), with 3–5 lateral teeth and two preapical setae; ta 1-4 without any preapical pseudospurs. Mid leg: width at apex of tibia 31–38 Μm long ( Fig. 83 I), tibia with single, apical and pectinate spur 14–26 Μm long with 3–7 teeth ( Fig. 83 J) and two preapical setae; ta 1-4 each with two preapical pseudospurs. Hind leg: width at apex of tibia 32–38 Μm long ( Fig. 83 K), tibia without spur; comb 8 setae; ta 1-4 without any preapical pseudospurs. Claws slender, hooked; pulvilli absent. Lengths and proportion of leg segments as in Table 57.

fe ti ta 1 ta 2 ta 3

p 1 400–518 372–494 318–454 190–259 114–143 p 2 501–640 456–505 513–564 192–258 110–148 p 3 492–556 441–581 534–569 236–263 133–175

ta 4 ta 5 LR BV SV

p 1 85–101 56–85 0.72–0.82 2.28–2.87 2.16–3.05 p 2 94–119 72–88 1.07–1.17 2.34–2.91 1.97–2.17 p 3 113–120 72–95 0.97–1.06 2.53–2.83 1.90–2.03 Hypopygium ( Fig. 83 M). Tergite IX arched, with 8–12 posterior setae. Membranous anal point broad, apical edge rounded. Phallapodeme 53–70 Μm long. Sternapodeme with distinct anterior process. Gonocoxite cylindrical, 123–160 ( 10) Μm long, 65–90 ( 10) Μm wide, with slightly concave inner margin. GcR 1.75–2.15 ( 10). Gonostylus simple and slender, 94–123 Μm long; megaseta 15–17 Μm long. HR 1.23–1.52 ( 10). HV 1.88–2.29 ( 8).

Adult female (n = 1)

Size. Total length 1.4 mm. Wing length 1.0 mm. Total length/wing length 1.41. Wing length/ profemur length 2.25.

Coloration. Head brown with dark brown occipital margin; pedicel and antenna brown; maxillary palp pale brown. Thorax brown with dark scutum. Wing membrane transparent without any marking. Legs brown. Abdomen completely brown. Seminal capsules brown.

Head. Temporal setae 12, uniserial. Eyes ratio 1.04. Tentorium 137 Μm long. Clypeus 85 Μm long, 64 Μm wide at largest part, bearing 21 setae. Cibarial pump 193 Μm long, as in male. Lengths of palpomeres 1–4 (in Μm): 32; 49; 100; 154; palpomeres 5 broken off. Antennal flagellum not measurable, diameter of pedicel 65 Μm.

Thorax. Antepronotum with 2 setae. Acrostichals 60, irregularly uniserial, starting close to antepronotum;

dorsocentrals 35, irregularly uniserial; prealars 17; supraalars 2. Scutellum with transverse row of 10 setae and group of numerous fine anterior setae.

Wing. Width 0.4 mm. Costa 0.9 mm long. R 2 + 3 absent. VR 0.60. WW 0.39. Brachiolum with 2 setae. Squama setiferous.

Legs. Fore leg: width at apex of tibia 34 Μm, tibia with single, apical and pectinate spur 14 Μm, with three lateral teeth and two preapical setae; preapical pseudospurs on ta 1-4 not observed. Mid leg: width at apex of tibia 38 Μm, tibia with single, apical and pectinate spur 21 Μm, with three lateral teeth and two preapical setae; preapical pseudospurs on ta 1-4 not observed. Hind leg: width at apex of tibia 46 Μm long, tibia without spur; comb with 8 bristles; preapical pseudospurs on ta 1-4 not observed. Claws slender, hooked; pulvilli absent. Lengths and proportion of leg segments as in Table 58.

fe ti ta 1 ta 2 ta 3 p 1 452 355 – – – p 2 562 450 – – – p 3 478 517 – – –

ta 4 ta 5 LR BV SV p 1 – – – – – p 2 – – – – – p 3 – – – – – Genitalia. Gonapophysis VIII broadly rounded, 61 Μm long. Coxosternapodeme 70 Μm long. Postgenital plate rounded. Cerci oval-quadrate, 51 Μm long and 14 Μm wide; with 9 elongated setae. Labia with inconspicuous microtrichia. Notum length 93 Μm long. Seminal capsules oval, 38 Μm long, 32 Μm wide, with conical shaped necks. Length ratio SCa/No 0.41.

Pupa (n = 13 unless otherwise stated)

Size. Abdomen 1.7–2.3 ( 12) mm long in male, 2.2 ( 1) mm long in female.

Coloration. Exuviae mostly pale brown; thoracic horn and apex of anal lobe brown.

Cephalothorax ( Figs 84 A–C). Frontal apotome smooth ( Fig. 84 A). Wing sheath smooth 0.8–1.1 mm long. Thoracic horn 216–350 Μm long and 80–138 Μm wide ( Fig. 84 B), THR 1.93–2.89, preapical indentation moderately deep. Membranous preapical papilla 22–40 ( 10) Μm long ( Fig. 84 C), PTH 0.06–0.16 ( 10), aeropyle tube simple, short, 22–33 ( 9) Μm long; plastron plate small. Horn sac well developed, completely filling respiratory atrium. Reticulation of respiratory atrium indistinct, external membrane with pale spinules. Basal lobe wedgeshaped. Thoracic comb with 7–8 conical tubercles ( Fig. 84 B).

Abdomen ( Figs 84 D–E). Tergite I with scar 104–148 Μm long. T I–V without shagreen, T VI–VIII with shagreen basally concentrated. Abdominal chaetotaxy as in figure 84 D. Abdominal segment VII with 4 LS-setae. A VIII with 5 LS-setae. Anal lobe 258–356 Μm long and 138–198 Μm wide ( Fig. 84 E), outer margins sclerotized, with 8–14 spines, longest spine 9–15 Μm long, inner margins of lobes membranous. ALR 1.55–2.30. Male genital sac extending much beyond apex of anal lobe.

4 th instar larva (n = 11 unless otherwise stated)

Coloration. Head pale yellow, without maculation; postoccipital margin brown. Second antennal segment brown; distal tooth of mandible and apex of ligula brown. Abdomen pale yellow; procercus and anal setae pale brown. Posterior parapod claws all pale yellow.

Head ( Fig. 85 A). Length 412–640 Μm, 235–316 Μm wide. IC 0.48–0.65. Surface smooth; lateroventral and posteroventral spine groups absent. Ventral cephalic setae S 9, S 10 and SSm forming a more or less straight line diagonal to longitudinal axis of head capsule ( Fig. 85 A).

Antenna ( Figs 85 B–C). Length 315–358 ( 8) Μm, A 1 217–260 ( 8) Μm long, with ring organ located 0.86–0.92 ( 6) from base, A 2 79–89 ( 8) Μm long. AR 2.26–2.66 ( 6). Blade longer than A 2 over-reached by accessory blade.

Maxilla ( Fig. 85 D). Basal palp segment 21–31 Μm long and 7–10 Μm wide at the middle, with ring organ located 0.69–0.87 ( 8) from base. PR 2.20–4.14. APR 7.82–11.6.

Mandible ( Fig. 85 E). Length 55–72 Μm. Sensillum campaniformium located 0.66–0.76 from apex, basal tooth bifid, with seta subdentalis projecting from sloping end towards apical tooth, accessory tooth present, AMD 3.29– 4.38.

Mentum and M appendage . Dorsomental teeth reduced; pseudoradula uniformly granulate.

Hypopharyngeal complex ( Figs 85 F–G). Ligula 45–60 Μm long, 25–27 Μm wide, with row of 5 teeth. IO 0.95– 1.02, MO 1.00– 1.08. Paraligula multi-toothed, with 4 teeth, 19–30 Μm long, inner tooth 15–28 Μm long, shorter than outer tooth. Pecten hypopharyngis with 7–8 teeth almost equal in size.

Body ( Figs 85 H–I). Without lateral fringe. Anterior parapods with simple claws. Procercus 140–204 Μm long, 24–37 Μm wide, with 7 anal setae, 377–561 Μm long. L/ W 4.56 –7.24. Supraanal seta well developed. Anal tubules 235–241 ( 2) Μm long. Posterior parapod 294–328 ( 3) Μm long; subbasal seta on posterior parapod serrated, with 4– 6 spines basally ( Fig. 85 H); parapod apex with numerous simple claws; bifid claw with V-shaped lower indentation ( Fig. 85 I). B/C 1.10–1.35 ( 10).

Remarks. Adult males of Labrundinia unicolor are quite similar to those of L. amandae and differences are discussed under this species. The pupae of L. unicolor also closely resemble those of L. amandae , but may be separated by a convoluted external margin of the thoracic horn. The larvae of L. unicolor appear most similar to those of L. amandae and were fully discussed on the remarks of this species. Labrundinia unicolor and L. amandae can also be separated by their COI gene sequences ( Silva et al. 2013). Labrundinia unicolor has been recorded so far only from São Paulo State, Brazil where it inhabits clear, unpolluted reservoirs.