Labrundinia amandae 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 : 10-16

Labrundinia amandae Silva sp. n.

( Figs 1–3 )

Labrundinia sp. 10 Silva et al. 2013: 601 (DNA barcodes).

Material examined. Type material: Holotype male with pupal and larval exuviae, Brazil: São Paulo, São Carlos, Ecological Park, 19.iv.2010, F. L. Silva ( MZUSP). 5 Paratypes: 1 male with pupal and larval exuviae same data as holotype ( NTNU); 1 male with pupal and larval exuviae same data as holotype except for Canchin reservoir, 25.vii.2007 ( NTNU); 1 female with pupal and larval exuviae same data as holotype except for Monjolinho stream, 11.iv.2011 ( NTNU); 2 pupa with larval exuviae same data as holotype ( NTNU).

Etymology. Named in honour of Amanda Carvalho de Andrade from Rio de Janeiro, in recognition for her friendship, kindness and continuous support.

Diagnostic characters. Labrundinia amandae sp. n. differs from other Labrundinia species by the combination of the following characters. Adult male: tentorium 149–192 Μm long; abdomen including hypopygium completely brown; sternapodeme with reduced anterior process. Pupa: thoracic horn semi-globose, preapical indentation moderately deep; abdominal segment VII with 4 LS-setae; male genital sac extending much beyond apex of anal lobe. Larva: surface smooth with small, dark brown spots ventrally, lateroventral and posteroventral spine groups absent; paraligula multi-toothed, with 4 teeth; subbasal seta of posterior parapod simple; bifid claw with V-shaped lower indentation.

Description. Adult male (n = 3)

Size. Total length 2.2–2.5 mm. Wing length 1.2–1.3 mm. Total length/wing length 1.75–2.04. Wing length/ profemur length 2.95–3.01.

Coloration. Head pale brown with dark occipital margin; pedicel and antenna brown; maxillary palp pale brown. Thorax pale brown with dark scutum. Wing membrane transparent without any marking. Legs pale brown. Abdomen including hypopygium brown ( Fig. 1L ).

Head ( Figs 1A–E ). Temporal setae 12, uniserial ( Fig. 1B ). Eye ratio 0.84–0.85 (2). Tentorium ( Fig. 1C ) 149– 192 Μm long. Clypeus 76–87 Μm long, 55–72 Μm wide at largest part, bearing 14–16 setae. Cibarial pump 183–191 Μm long ( Fig. 1D ), with anterior margin concave. Lengths of palpomeres 1–5 (in Μm): 41–45 (2); 47–52 (2); 98– 105 (2); 147–156 (2); 211 (1). Antennal flagellum 790–797 Μm long, diameter of pedicel 125–129 (2) Μm, apical setae single ( Fig. 1E ), AR 1.21–1.29.

Thorax. Antepronotum with 2 (2) lateral setae. Acrostichals 38–55, biserial, diverging evenly posteriorly, starting close to antepronotum and almost reaching scutellum; dorsocentrals 22–26, irregularly uniserial; prealars 8–9; supraalars 2. Anapleural suture ratio 0.48–0.53. Scutellum with transverse row of 10–11 setae and group of numerous fine anterior setae.

Wing ( Fig. 1F ). Width 0.4 mm. Costa 1.1–1.2 mm long. R2+3 absent. VR 0.69–0.76. WW 0.30–0.32. Brachiolum with 2 setae. Squama setiferous.

Legs ( Figs 1G–K ). Fore leg: width at apex of tibia 31–37 Μm ( Fig. 1G ), tibia with single, apical and pectinate spur 18–19 Μm long ( Fig. 1H ), with three lateral teeth and two preapical setae; ta1-4 without any preapical pseudospurs. Mid leg: width at apex of tibia 32–38 Μm long ( Fig. 1I ), tibia with single, apical and pectinate spur 23–30 Μm long with lateral three lateral teeth ( Fig. 1J ) and two preapical setae; ta1-4 each with two preapical pseudospurs. Hind leg: width at apex of tibia 34–42 Μm long ( Fig. 1K ), tibia without spur; comb with 7 bristles; ta1- 4 without any preapical pseudospurs. Claws slender, hooked; pulvilli absent. Lengths and proportion of leg segments as in Table 2.

fe ti ta1 ta2 ta3

p1 400–436 385–430 304–340 181–188 128–137 p2 584–616 456–493 480–487 253–275 131–145 p3 526–545 519–561 546–563 252–257 166–168

ta4 ta5 LR BV SV

p1 86–98 56–58 0.75–0.79 2.50–2.51 2.95–3.07 p2 93–100 75–82 0.98–1.07 2.65–2.75 2.13–2.29 p3 109–112 88–91 1.00–1.05 2.57–2.69 1.93–1.97 Hypopygium ( Fig. 1M ). Tergite IX arched, with 8 posterior setae. Membranous anal point small, apical edge rounded. Phallapodeme 58–71 (2) Μm long. Sternapodeme with reduced anterior process. Gonocoxite cylindrical, 143–154 Μm long, 72–75 Μm wide, with slightly concave inner margin. GcR 1.93–2.12. Gonostylus simple and slender, 97–106 Μm long; megaseta 15–16 Μm long. HR 1.46–1.48. HV 2.21–2.40.

Adult female (n = 1)

Size. Total length 1.3 mm. Wing length 0.8 mm. Total length/wing length 1.48. Wing length/ profemur length 2.76.

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 completely dark brown. Seminal capsules brown.

Head. Temporal setae 12, uniserial. Eyes ratio 0.94. Tentorium 149 Μm long. Clypeus 85 Μm long, 61 Μm wide at largest part, bearing 19 setae. Cibarial pump 174 Μm long, as in male. Lengths of palpomeres 1–3 (in Μm): 31; 44; 85. Antennal flagellum 333, AR 0.34 Μm long, diameter of pedicel 51 Μm.

Thorax. Antepronotum with 2 lateral setae. Acrostichals 35, irregularly uniserial, starting close to antepronotum; dorsocentrals 35, irregularly biserial; prealars 15; supraalars 3. Scutellum with transverse row of 10 setae and group of numerous fine anterior setae.

Wing. Width 0.3 mm. Costa 0.8 mm long. R2+3 absent. VR 0.69. WW 0.38. Brachiolum with 2 setae. Squama setiferous.

Legs. Fore leg: width at apex of tibia 36 Μm, tibia with single, apical and pectinate spur 15 Μm, with three lateral teeth and two preapical setae; preapical pseudospurs on ta1-4 not observed. Mid leg: width at apex of tibia 44 Μm long, tibia with two preapical setae, apical spur not observed; preapical pseudospurs on Ta1-4 not observed. Hind leg: width at apex of tibia 41 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 3.

fe ti ta1 ta2 ta3 p1 315 305 262 128 101 p2 495 369 – – – p3 439 488 – – –

ta4 ta5 LR BV SV p1 63 59 0.86 2.51 2.37 p2 – – – – – p3 – – – – – Genitalia. Gonapophysis VIII broadly rounded, 63 Μm long. Coxosternapodeme 69 Μm long. Postgenital plate rounded. Cerci oval-quadrate, 35 Μm long and 11 Μm wide; with 4 elongated setae. Labia with inconspicuous microtrichia. Notum length 90 Μm long. Seminal capsules oval, 36 Μm long, 28 Μm wide, with conical shaped necks. Length ratio SCa/No 0.40.

Pupa (n = 6 unless otherwise stated)

Size. Abdomen 1.8–2.2 (4) mm long in male, 1.7 (1) mm long in female.

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

Cephalothorax ( Figs 2A–C ). Frontal apotome smooth ( Fig.2A ). Wing sheath smooth 0.7–1.0 mm long. Thoracic horn 203–239 Μm long and 73–87 Μm wide ( Fig. 2B ), THR 2.57–2.81, preapical indentation moderately deep. Membranous preapical papilla 23–43 Μm long ( Fig. 2C ), PTH 0.09–0.17, aeropyle tube simple, short, 18–28 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 8–10 conical tubercles ( Fig. 2B ).

Abdomen ( Figs 2D–E ). Tergite I with scar 114–132 Μm long. T I–VI without shagreen, T VII–VIII with shagreen basal concentrated. Abdominal chaetotaxy as in figure 2D. Abdominal segment VII with 4 LS-setae. A VIII with 5 LS-setae. Anal lobe 263–318 Μm long and 142–185 Μm wide ( Fig. 2E ), outer margins sclerotized, with 8–10 spines, longest spine 10–14 Μm long, inner margins of lobes membranous. ALR 1.48–2.20. Male genital sac extending much beyond apex of anal lobe.

4th instar larva (n = 6 unless otherwise stated)

Coloration. Head pale yellow, with small, dark brown spots ventrally; 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. 3A ). Length 464–514 Μm, 283–317 Μm wide. Surface smooth; lateroventral and posteroventral spine groups absent; IC 0.56–0.67. Ventral cephalic setae S9, S10 and SSm forming a straight line diagonal to longitudinal axis of head capsule ( Fig. 3A ).

Antenna ( Figs 3B–C ). Length 311–348 Μm, A1 219–244 Μm long, with ring organ located 0.86–0.90 (4) from base, A2 83–89 Μm long. AR 2.32–2.45. Blade longer than A2 over-reached by accessory blade.

Maxilla ( Fig. 3D ). Basal palp segment 23–32 Μm long and 7–11 wide at the middle, with ring organ located 0.76–0.84 (5) from base. PR 2.82–3.28. APR 7.31–10.2.

Mandible ( Fig. 3E ). Length 63–86 Μm. Sensillum campaniformium located 0.67–0.75 from apex, basal tooth bifid, with seta subdentalis projecting from sloping end towards apical tooth, accessory tooth present, AMD 2.56– 3.89.

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

Hypopharyngeal complex ( Figs 3F–G ). Ligula 41–58 Μm long, 22–26 Μm wide, with row of 5 teeth. IO 0.92– 0.98, MO 1.00–1.04. Paraligula multi-toothed, with 4 teeth, 19–27 Μm long, inner tooth 13–19 Μm long, shorter than outer tooth. Pecten hypopharyngis with 8 teeth almost equal in size.

Body ( Figs 3H–I ). Without lateral fringe. Anterior parapods with simple claws. Procercus 146–171 (5) Μm long, 20–33 (5) Μm wide, with 7 anal setae, 518–552 (3) Μm long. L/ W 4.47 –7.48 (5). Supraanal seta well developed. Anal tubules not measurable. Posterior parapod 324 (1) Μm long; subbasal seta serrated, with 3–4 (5) spines basally ( Fig. 3H ); parapod apex with numerous simple claws; bifid claw with V-shaped lower indentation ( Fig. 3I ). B/C 1.02 (1).

Remarks. Labrundinia amandae is very similar to L. unicolor in the adult males, but can be separated from the former by the longer tentorium (149–192 Μm in L. amandae vs 90–126 Μm in L. unicolor ). The pupal exuviae are perhaps most similar to those of L. multidentata and L. tenata , but can be distinguished from these species by having 4 LS-setae on the abdominal segment VII. The larvae are apparently most similar to those of L. unicolor , but L. amandae can be separated by having a yellow head with small, dark brown ventral spots. Labrundinia amandae , L. tenata and L. unicolor can also be separated by their partial COI gene sequences ( Silva et al. 2013). Labrundinia amandae has so far been recorded from two localities in São Paulo State, Brazil. The larvae were collected in small dams characterized by a predominance of aquatic macrophytes.

Figures

FIGURES 1 A – M. Labrundinia amandae Silva sp. n., 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 2 A – E. Labrundinia amandae Silva sp. n., 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 3 A – I. Labrundinia amandae Silva sp. n., 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. Subbasal seta of posterior parapod. I. Bifid claw of posterior parapod.