Labrundinia carolae 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 : 24-29

Labrundinia carolae Silva sp. n.

( Figs 8–10 )

Material examined. Type material: Holotype male with pupal and larval exuviae, Brazil: Paraná, Ponta Grossa, Vila Velha State Park, 2.iv.2008, C. S. N. Oliveira ( MZUSP). 2 Paratypes: 1 pharate male data as holotype ( NTNU); 1 pharate female with larval exuviae, data as holotype ( NTNU).

Etymology. Named in honour of Caroline (Carol) Silva Neubern de Oliveira for her friendship and for collect the species in Ponta Grossa, Brazil.

Diagnostic characters. Labrundinia carolae sp. n. differs from other Labrundinia species by the combination of the following characters. Adult male: abdominal tergites I, VI, VIII completely brown, II–V, VII with continuous brown transverse band near proximal margin; hypopygium brown, sternapodeme with reduced anterior process. Pupa: thoracic horn shaped like the number ‘9’; shagreen on sternite II with prominent spines; apical spines 23–29 Μm long; genital sac almost reaching apex of the anal lobe. Larva: head capsule surface smooth; lateroventral spine group absent, posteroventral spine group present with 20–22 small spines; AR 2.80–2.93; subbasal seta of posterior parapod simple; bifid claw brown, with U-shaped lower indentation.

Description. Adult male (n = 2 unless otherwise stated)

Size. Total length 2.4 mm. Wing length 1.4 (1) mm. Total length/wing length 1.77 (1). Wing length/length of profemur 3.10 (1).

Coloration. Head pale brown with dark brown occipital margin; pedicel and antenna brown; maxillary palp pale brown. Thorax completely brown. Wing membrane transparent without any marking. Legs brown. Abdominal tergites I, VI, VIII completely brown, II–V, VII with continuous brown transverse band near proximal margin; hypopygium brown ( Fig. 8L ).

Head ( Figs 8A–E ). Temporal setae 12, uniserial ( Fig. 8B ). Eye ratio 1.17 (1). Tentorium ( Fig. 8C ) 154–160 Μm long. Clypeus 73–82 Μm long, 65–66 Μm wide at largest part, bearing 11–13 setae. Cibarial pump 177–180 Μm long ( Fig. 8D ), with anterior margin concave. Lengths of palpomeres 1–5 (in Μm): 35 (1); 49 (1); 83 (1); 95 (1); 170 (1). Antennal flagellum 761 (1) Μm long, diameter of pedicel 125 (1) Μm, apical setae single ( Fig. 8E ), AR 1.05.

Thorax. Antepronotum with 2–3 lateral setae. Acrostichals 48–52, biserial, diverging evenly posteriorly, starting close to antepronotum and almost reaching scutellum; dorsocentrals 16–20, irregularly uniserial; prealars 7–8; supraalars 3. Anapleural suture ratio 0.43–0.45. Scutellum with transverse row of 6 setae and group of numerous fine anterior setae.

Wing ( Fig. 8F ). Width 0.4 (1) mm. Costa 1.13 (1) mm long. R2+3 present. VR 0.74 (1). WW 0.28 (1). Brachiolum with 2 setae. Squama setiferous.

Legs ( Figs 8G–K ). Fore leg: width at apex of tibia 36 (1) Μm ( Fig. 8G ), tibia with single, apical and pectinate spur 17 (1) Μm long ( Fig. 8H ), with three lateral teeth and two preapical setae; ta1-4 without any preapical pseudospurs. Mid leg: width at apex of tibia 34 (1) Μm long ( Fig. 8I ), tibia with single, apical and pectinate spur 24 (1) Μm long with three lateral teeth ( Fig. 8J ) and two preapical setae; ta1-4 each with two preapical pseudospurs. Hind leg: width at apex of tibia 43 (1) Μm long ( Fig. 8K ), tibia without spur; comb with 5 bristles; ta1-4 without any preapical pseudospurs. Claws slender, hooked; pulvilli absent. Lengths and proportion of leg segments as in Table 7.

fe ti ta1 ta2 ta3

p1 438 456 315 226 142 p2 566 457 557 274 146 p3 552 618 647 288 195

ta4 ta5 LR BV SV p1 107 85 0.69 2.16 2.83 p2 98 83 1.22 2.62 1.84 p3 121 86 1.05 2.63 1.81 Hypopygium ( Fig. 8M ). Tergite IX arched, with 9–10 posterior setae. Membranous anal point trapezoidal, apical edge slightly concave. Phallapodeme 49–59 Μm long. Sternapodeme with reduced anterior process. Gonocoxite cylindrical, 110 (1) Μm long, 45 (1) Μm wide, with slightly concave inner margin. GcR 2.49 (1). Gonostylus simple and slender, 65–84 Μm long; megaseta 9–11 Μm long. HR 1.71 (1). HV 3.74 (1).

Adult female (n = 1)

Size. Total length 2.4 mm.

Coloration as in male except for abdomen completely brown. Seminal capsules brown.

Genitalia. Gonapophysis VIII broadly rounded, 55 Μm long. Coxosternapodeme 52 Μm long. Postgenital plate rounded. Cerci oval-quadrate, 31 Μm long and 15 Μm wide; with 6 elongated setae. Labia with inconspicuous microtrichia. Notum length 69 Μm long. Seminal capsules oval, 40 Μm long, 20 Μm wide, with conical shaped necks. Length ratio SCa/No 0.58.

Pupa (n = 2 unless otherwise stated)

Size. Abdomen 2.2 mm long in male.

Coloration. Exuviae and thoracic horn brown.

Cephalothorax ( Figs 9A–C ). Frontal apotome smooth ( Fig. 9A ). Wing sheath smooth 0.7–0.9 mm long. Thoracic horn 231–267 Μm long and 100–120 Μm wide ( Fig. 9B ), THR 2.23–2.31, preapical indentation deep. Membranous preapical papilla 31–32 Μm long ( Fig. 9C ), PTH 0.12–013, aeropyle tube simple, elongated and slender, 53 (1) Μm long; plastron plate small. Horn sac moderately developed. Reticulation of respiratory atrium indistinct, spinules on external membrane not observed. Basal lobe wedge-shaped. Thoracic comb with 9 (1) conical tubercles ( Fig. 9B ).

Abdomen ( Figs 9D–F ). Tergite I with scar 111–133 Μm long. T I–VI without shagreen, T VII–VIII with shagreen basally concentrated. Sternite II with prominent spines ( Fig. 9D ). Abdominal chaetotaxy as in figure 9E. Abdominal segment VII with 4 LS-setae. A VIII with 5 LS-setae. Anal lobe 338–401 Μm long and 149–163 Μm wide ( Fig. 9F ), outer margins sclerotized, with 10 spines, longest spine 23–29 Μm long, inner margins of lobes membranous. ALR 2.08–2.68. Male genital sac almost reaching apex of anal lobe.

4th instar larva (n = 2 unless otherwise stated)

Coloration. Head pale yellow, without maculation; postoccipital margin brown. Second antennal segment pale 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 to pale brown except for bifid claw brown.

Head ( Fig. 10A ). Length 550–602 Μm, 338–385 Μm wide. IC 0.61–0.64. Surface smooth; lateroventral spine group absent; posteroventral spine group present with 20–22 small spines. Ventral cephalic setae S9, S10 and ventral pore (VP) forming a right angle ( Fig. 10A ).

Antenna ( Figs 10B–C ). Length 333–378 Μm, A1 226–245 Μm long, with ring organ located 0.90–0.91 from base, A2 71–76 Μm long. AR 2.80–2.93. Blade and accessory blade not measurable.

Maxilla ( Fig. 10D ). Basal palp segment 34–35 Μm long and 7–9 Μm wide at the middle, with ring organ located 0.74–0.80 from base. PR 3.93–4.77. APR 6.56–7.02.

Mandible ( Fig. 10E ). Length 48–51 Μm. Sensillum campaniformium located 0.76–0.87 from apex, basal tooth bifid, with seta subdentalis projecting from sloping end towards apical tooth, accessory tooth present, AMD 4.79– 4.75.

Mentum and M appendage . Dorsomental teeth reduced; pseudoradula uniformly granulate, 118 (1) Μm.

Hypopharyngeal complex ( Figs 10F–G ). Ligula 57–61 Μm long, 31–36 Μm wide, with row of 5 teeth. IO

0.96–0.97, MO 1.02–1.01. Paraligula bifid, 29–30 Μm long, inner tooth 21–22 Μm long, shorter than outer tooth. Pecten hypopharyngis with 7 teeth almost equal in size.

Body ( Figs 10H–I ). Without lateral fringe. Anterior parapods with simple claws. Procercus 195–204 Μm long, 29–30 Μm wide, with 7 anal setae 518–525 Μm long. L/ W 6.68 –6.88. Supraanal seta well developed. Anal tubules not measurable. Posterior parapod not measurable; subbasal seta on posterior parapod simple, without spines ( Fig. 10H ); parapod apex with numerous simple claws; bifid claw with U-shaped lower indentation ( Fig. 10I ). B/C 1.25.

Remarks. The adult males of Labrundinia carolae are similar to those of L. mayaca and L. sofiae . However, the brown hypopygium and the transverse band on abdominal tergite VI may distinguish L. carolae from L. mayaca , whereas the presence of 5 bristles in the hind tibial comb and the posterior transverse band on abdominal tergite VI will separate it from L. sofiae . The pupae of L. carolae appear most similar to those of L. virescens , but can be separated from this species by the simple shagreen-spinules on sternite II in contrast to the multi-toothed spinules present in L. virescens . The larvae of L. carolae are very similar to those of L. mayaca , but can be distinguished by the broader ligula. Labrundinia carolae has been recorded only from its type locality. The larvae were collected in a small lake characterized by a predominance of aquatic macrophytes.

Figures

FIGURES 8 A – M. Labrundinia carolae 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 9 A – F. Labrundinia carolae 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. Spines on sternite II. E. Abdominal segments with chaetotaxy, dorsal aspect. F. Anal lobe and male genital sac, ventral aspect.

FIGURES 10 A – I. Labrundinia carolae 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.