Labrundinia tenata Roback, 1987

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 : 163-169

Labrundinia tenata Roback, 1987

( Figs 79–81 )

Labrundinia tenata Roback, 1987: 214 (description of male); and Fonseca-Gessner 2009: 541 (description of male and immatures); Silva et al. 2013: 600 (DNA barcodes).

Material examined. Type material: Holotype male, Colombia: Departamento del Meta , Puerto López, Laguna Mozambique, 16 km s. w. of Puerto López, 25.ii.1972, N. R. Foster ( ANSP). 4 Paratypes: 2 males same data as holotype ( ANSP); 2 males same data as holotype except for 9.ii.1972 ( ANSP).

Additional material: 2 males with pupal and larval exuviae, Brazil: São Paulo, São Carlos, Fazzari resevoir, associated with the aquatic macrophyte, Salvinia auriculata , 22.v.2008, F. L. Silva ( NTNU); 1 male with pupal and larval exuviae as previous except for 14.v.2008 ( NTNU). 1 male with pupal and larval exuviae as previous except for 27.xi.2007 ( NTNU). 1 male with pupal and larval exuviae as previous except for 4.v.2007 ( NTNU). 1 male with pupal exuviae as previous except for Monjolinho stream, 27.vii.2009 ( NTNU). 1 female with pupal and larval exuviae as previous except for Valparaíso lake, 4.iv.2011 ( NTNU). 1 female with pupal and larval exuviae as previous except for 19.iv.2011 ( NTNU).

Diagnostic characters. Labrundinia tenata differs from other Labrundinia species by the combination of the following characters. Adult male: abdominal tergite I pale brown, T II–VI with continuous brown transverse band near proximal margin, T VII–VIII completely brown; hypopygium brown, sternapodeme rounded, with anterior process absent. Pupa: thoracic horn semi-globose, preapical indentation moderately deep, forming a small diverticulum; abdominal segment VII with 2 LS-setae. Larva: surface of head capsule covered with spinules, lateroventral spine group absent, posteroventral spine group present, with 5–13 spines; subbasal seta of posterior parapod simple; serrated claw present; bifid claw with U-shaped lower indentation.

Description. Adult male (n = 11)

Size. Total length 1.6–2.3 (8) mm. Wing length 1.0– 1.2 mm. Total length/wing length 1.55–1.97 (8). Wing length/ profemur length 2.43–3.12 (9).

Coloration. Head brown with dark brown occipital margin; pedicel and antenna brown; maxillary palp pale. Thorax pale brown with dark scutum; antepronotum pale; supraalar callus brown. Wing membrane transparent without any marking. Legs pale brown. Abdominal tergite I pale brown, T II–VI with continuous brown transverse band near proximal margin, T VII–VIII completely brown; hypopygium brown ( Fig. 79L ).

Head ( Figs 79A–E ). Temporal setae 10–13, uniserial ( Fig. 79B ). Eye ratio 1.08–1.97 (7). Tentorium ( Fig. 79C ) 127–145 (5) Μm long. Clypeus 63–104 (10) Μm long, 49–75 (10) Μm wide at largest part, bearing 9–13 (10) setae. Cibarial pump 132–171 Μm long ( Fig. 79D ), with anterior margin concave. Lengths of palpomeres 1–5 (in Μm): 29–44 (8); 39–56 (8); 84–117 (8); 115–127 (5); 157–199 (4). Antennal flagellum 599–768 (7) Μm long, diameter of pedicel 92–113 (9) Μm, apical setae single ( Fig. 79E ), AR 1.04–1.24 (7).

Thorax. Antepronotum with 2–5 (9) lateral setae. Acrostichals 26–40 (7), biserial, diverging evenly posteriorly, starting close to antepronotum and almost reaching scutellum; dorsocentrals 13–20 (10), irregularly uniserial; prealars 5–6 (10); supraalars 2. Anapleural suture ratio 0.33–0.54. Scutellum with transverse row of 6–8 setae and group of numerous fine anterior setae.

Wing ( Fig. 79F ). Width 0.3–0.4 (10) mm. Costa 0.9–1.0 mm long. R2+3 absent. VR 0.67–0.76 (10). WW 0.28– 0.31 (10). Brachiolum with 2 setae. Squama setiferous.

Legs ( Figs 79G–K ). Fore leg: width at apex of tibia 30–39 (9) Μm ( Fig. 79G ), tibia with single, apical and pectinate spur 10–14 (10) Μm long ( Fig. 79H ), with three lateral teeth and two preapical setae; ta1-4 without any preapical pseudospurs. Mid leg: width at apex of tibia 31–46 (10) Μm long ( Fig. 79I ), tibia with single, apical and pectinate spur 14–28 Μm long with three lateral teeth ( Fig. 79J ) and two preapical setae; ta1-4 each with two preapical pseudospurs. Hind leg: width at apex of tibia 31–46 (10) Μm long ( Fig. 79K ), tibia with spur; comb 7 (9) setae; ta1-4 without any preapical pseudospurs. Claws slender, hooked, appear to be bifid; pulvilli absent. Lengths and proportion of leg segments as in Table 54.

fe ti ta1 ta2 ta3

p1 353–437 344–415 242–318 139–172 116–142 p2 401–500 367–457 424–531 191–237 123–141 p3 367–466 477–580 504–549 198–245 104–175

ta4 ta5 LR BV SV

p1 86–101 54–64 0.71–0.76 2.16–2.50 2.46–2.90 p2 81–94 60–87 1.01–1.22 2.68–2.79 1.67–1.92 p3 87–96 70–77 0.85–1.05 2.79–3.03 1.79–2.26 Hypopygium ( Fig. 79M ). Tergite IX arched, with 7–12 posterior setae. Membranous anal point trapezoidal, apical edge slightly straight. Phallapodeme 43–55 (10) Μm long. Sternapodeme with anterior process absent. Gonocoxite cylindrical, 94–104 (7) Μm long, 41–63 (7) Μm wide, with slightly concave inner margin. GcR 1.60– 2.25 (7). Gonostylus simple and slender, 61–71 (7) Μm long; megaseta 10–16 Μm long. HR 1.44–1.54 (7). HV 2.85–3.77 (7).

Adult female (n = 2)

Size. Total length 0.9–1.1 mm. Wing length 0.8–0.9 mm. Total length/wing length 1.14–1.17. Wing length/ profemur length 2.69–3.94.

Coloration. Head pale brown with dark brown occipital margin; pedicel and antenna brown; maxillary palp pale brown. Thorax brown with dark scutum; antepronotum pale brown. Wing membrane transparent without any marking. Legs pale brown. Abdomen pale brown, with dark brown transverse bands near proximal margin, not much distinguishable. Seminal capsules brown.

Head. Temporal setae 10, uniserial. Eyes ratio 1.22 (1). Tentorium 111 Μm long. Clypeus 72–88 Μm long, 48– 50 Μm wide at largest part, bearing 15–17 setae. Cibarial pump 136–179 Μm long, as in male. Lengths of palpomeres 1–4 (in Μm): 28–33; 38–44; 80–112; 126 (1); palpomeres 5 broken off. Antennal flagellum 232–294 Μm long, diameter of pedicel 52–56 Μm, AR 0.35–0.36.

Thorax. Antepronotum with 1–3 lateral setae. Acrostichals 30–38, irregularly uniserial, starting close to antepronotum; dorsocentrals 24–32, irregularly uniserial; prealars 5–8; supraalars 2. Scutellum with transverse row of 8 setae and group of numerous fine anterior setae.

Wing. Width 0.3–0.4 mm. Costa 0.7–0.8 mm long. R2+3 absent. VR 0.69–0.70. WW 0.37–0.39. Brachiolum with 2 setae. Squama setiferous.

Legs. Fore leg: width at apex of tibia 33–34 Μm, tibia with single, apical and pectinate spur 16–17 Μm, with three lateral teeth and two preapical setae; preapical pseudospurs on ta1-4 not observed. Mid leg: width at apex of tibia 44–47 Μm, tibia with single, apical and pectinate spur 17–28 Μm, with three lateral teeth and two preapical setae; preapical pseudospurs on ta1-4 not observed. Hind leg: width at apex of tibia 30–37 Μm long, tibia without spur; comb with 7 bristles; preapical pseudospurs on ta1-4 not observed. Claws slender, hooked; pulvilli absent. Lengths and proportion of leg segments as in Table 55.

fe ti ta1 ta2 ta3 p1 238–295 288–357 238 103 74 p2 485–549 444–468 – – –

p3 340–497 408–512 290–380 134–160 88–106

ta4 ta5 LR BV SV p1 61 47 0.83 2.89 2.44 p2 – – – – –

p3 65–70 56–63 0.93 3.01–3.54 1.97 Genitalia. Gonapophysis VIII broadly rounded, 44–69 Μm long. Coxosternapodeme 64–67 Μm long. Postgenital plate rounded. Cerci oval-quadrate, 33–44 Μm long and 10–21 Μm wide; with 8–10 elongated setae. Labia with inconspicuous microtrichia. Notum length 81–82 Μm long. Seminal capsules oval, 31–35 Μm long, 30– 31 Μm wide, with conical shaped necks. Length ratio SCa/No 0.39–0.43.

Pupa (n = 8 unless otherwise stated)

Size. Abdomen 1.5–2.0 (6) mm long in male, 1.5–1.8 (2) mm long in female.

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

Cephalothorax ( Figs 80A–C ). Frontal apotome smooth ( Fig.80A ). Wing sheath smooth 0.6–0.8 mm long. Thoracic horn 272–226 Μm long and 60–83 Μm wide ( Fig. 80B ), THR 2.72–3.41, preapical indentation moderately deep. Membranous preapical papilla 27–35 Μm long ( Fig. 80C ), PTH 0.13–0.18, aeropyle tube simple, short, 17– 25 Μm long; plastron plate small. Horn sac well developed, completely filling respiratory atrium. External membrane with pale spinules basally concentrated. Basal lobe wedge-shaped. Thoracic comb with 8–11 conical tubercles ( Fig. 80B ).

Abdomen ( Figs 80D–E ). Tergite I with scar 104–122 Μm long. T I–VI without shagreen, T VII–VIII with shagreen basal concentrated. Abdominal chaetotaxy as in figure 80D. Abdominal segment VII with 2 LS-setae. A VIII with 5 LS-setae. Anal lobe 215–285 Μm long and 133–192 Μm wide ( Fig. 80E ), outer margins sclerotized, with 6–10 spines, longest spine 9–15 Μm long, inner margins of lobes membranous. ALR 1.05–1.16. Male genital sac almost reaching much beyond apex of anal lobe.

4th instar larva (n = 6 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. 81A ). Length 480–556 Μm, 292–383 Μm wide. IC 0.59–0.69. Surface covered with small spinules; lateroventral spine group absent; posteroventral spine group present, with 5–13 spines. Ventral cephalic setae S9, S10 and ventral pore (VP) forming a more or less right angle ( Fig. 81A ).

Antenna ( Figs 81B–C ). Length 296–314 Μm, A1 197–207 Μm long, with ring organ located 0.90–0.95 (5) from base, A2 87–97 Μm long. AR 1.76–2.05. Blade longer than A2 over-reached by accessory blade.

Maxilla ( Fig. 81D ). Basal palp segment 22–32 Μm long and 6–8 Μm wide at the middle, with ring organ located 0.73–0.90 (5) from base. PR 3.72–5.02. APR 6.59–9.22.

Mandible ( Fig. 81E ). Length 56–74 Μm. Sensillum campaniformium located 0.65–0.82 from apex, basal tooth bifid, with seta subdentalis projecting from sloping end towards apical tooth, accessory tooth present, AMD 2.64– 3.73.

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

Hypopharyngeal complex ( Figs 81F–G ). Ligula 44–65 Μm long, 25–28 Μm wide, with row of 5 teeth. IO 0.93– 0.98, MO 1.02–1.04. Paraligula bifid, 21–27 Μm long, inner tooth 16–21 Μm long, shorter than outer tooth. Pecten hypopharyngis with 6 teeth almost equal in size.

Body ( Figs 81H–I ). Without lateral fringe. Anterior parapods with simple claws. Procercus 129–142 Μm long, 19–29 Μm wide, with 7 anal setae, 404–516 (5) Μm long. L/ W 4.95 –7.10. Supraanal seta well developed. Anal tubules176 (1) Μm long. Posterior parapod 401 (1) Μm long; subbasal seta on posterior parapod simple, with 2–5 small spines basally ( Fig. 81H ); parapod apex with numerous simple claws, with serrated claw; bifid claw with Ushaped lower indentation ( Fig. 81I ). B/C 0.76–1.04 (4).

Remarks. Adult males of Labrundinia tenata are very similar to those of L. kogilamae and differences are discussed under this species. The pupae of L. tenata resemble those of L. multidentata , but can be separated by the genital sac reaching much beyond apex of the anal lobe. The larvae of L. tenata may be distinguished from those of the related species L. multidentata , L. parareniformis and L. reniformis by the bifid claws of the posterior parapods having U-shaped lower indentation. Labrundinia tenata was originally described based on specimens from Colombia while its immatures were described from material sampled in Southeast Brazil (Silva & Fonseca- Gessner 2009). This tentative association was based on abdominal coloration pattern and on the shape of the sternapodeme in the adult male: rounded and without anterior process. Even though the Colombian specimens seem to be larger and darker, we have not been able to find any consistent differences that could justify a separate species for the Brazilian specimens. Labrundinia tenata has been recorded from its type locality in Colombia and from the southeast of Brazil. The larvae were collected associated with the aquatic macrophyte, Salvinia auriculata in two reservoirs and in a small stream.

Figures

FIGURES 79 A – M. Labrundinia tenata Roback, adult male. A. Head, frontal view. B. Temporal setae. C. Tentorium. D. Cibarial pump. E. Apex of antenna. F. Wing. G. Apex of fore tibia. H. Fore tibial spur. I. Apex of mid tibia. J. Mid tibial spur. K. Apex of hind tibia with comb. L. Abdominal coloration pattern, dorsal aspect. M. Hypopygium, left: ventral aspect, right: dorsal aspect.

FIGURES 80 A – E. Labrundinia tenata Roback, pupa. A. Frontal apotome. B. Thoracic horn with basal lobe and thoracic comb. C. Apex of thoracic horn showing preapical papilla. D. Abdominal segments with chaetotaxy, dorsal aspect. E. Anal lobe and male genital sac, ventral aspect.

FIGURES 81 A – J. Labrundinia tenata Roback, larva. A. Head with chaetotaxy, left: ventral aspect, right: dorsal aspect. B. Antenna. C. Apex of antenna. D. Maxillary palp. E. Mandible. F. Ligula and paraligula. G. Pecten hypopharyngis. H. Serrated claw of posterior parapod. I. Subbasal seta of posterior parapod. J. Bifid claw of posterior parapod.