Polypedilum, Pinho, Luiz Carlos, Mendes, Humberto Fonseca, Andersen, Trond & Marcondes, Carlos Brisola, 2013

Pinho, Luiz Carlos, Mendes, Humberto Fonseca, Andersen, Trond & Marcondes, Carlos Brisola, 2013, Bromelicolous Polypedilum Kieffer from South Brazil (Diptera: Chironomidae), Zootaxa 3652 (5), pp. 569-581 : 575-580

Polypedilum (Polypedilum) solimoes Bidawid-Kafka

( Figs 17–32 )

Polypedilum (Polypedilum) solimoes Bidawid-Kafka, 1996: 228 . Polypedilum solimoes Bidawid-Kafka ; Spies & Reiss (1996). Polypedilum sp. n. 3 Pinho et al. (2005).

Material examined. 1 male with larval and pupal exuviae, BRAZIL: Santa Catarina State, Florianópolis, Santinho Restinga, 27°28’05’’S, 48°22’58’’W, 03.x.2004, in Aechmea lindenii, F.H. Platt ; 1 female with larval and pupal exuviae, same data as previous. 3 males, BRAZIL: Santa Catarina State, Florianópolis, Unidade de Conservação Ambiental Desterro (UCAD), 27°31’51”S, 48°30’44”W, 04–19.ix.2003, emergence trap, in Nidularium innocentii, L.C. Pinho & C.B. Marcondes, Code 16. 1 male, same data as previous, except for: Code 12. 2 males, same data as previous, except for: 03–24.x.2003, Code 40. 1 male, same data as previous, except for: 24.x–11.xi.2003, Code 59.

The species was described and figured by Bidawid-Kafka (1996) based on four males collected at Rio Tarumã, a tributary to Rio Negro in the Amazonas. The males are pale with a wing length of about 1.38 mm and an AR of about 1.41. The anal point is long, narrow and parallel-sided and the superior volsella is narrow, curved with strong lateral seta and 3–4 strong setae at base. Head, wing, thorax, apex of fore tibia and hypopygium of the male from Santa Catarina as in Figures 17–22 . Below we describe the female and the immatures based on material from Santa Catarina. The female can be recognized on the translucent wings, weakly setose clypeus (<20 setae) and the large subquadrangular dorsomesal lobe of the genitalia. The pupae by its tergite VII, which has an anterior band of very strong shagreen, an antero-median field of finer shagreen and two small postero-lateral patches of fine shagreen. The larvae can be distinguished from other Neotropical species by the combination of having first and third lateral teeth of mentum much lower than median and second lateral teeth, mandible with serrate inner margin, and nonprojected posterior margin of the ventromental plates.

Description. Female (n = 4, except when otherwise stated). Total length 1.73–2.14, 1.91 mm. Wing length 1.04–1.33, 1.23 mm. Total length / wing length 1.41–1.65, 1.56. Wing length / length of profemur 1.78–1.90, 1.85. Coloration. Head brown. Thorax brown with darker median vittae, postnotum, scutellum, anepisternum and dorsal one-third of preepisternum; halteres dark brown. Legs yellow with brown fore femur and tibia. Abdominal segments entirely brown.

Head. Frontal tubercles absent. AR 0.50–0.53 (3). Temporal setae 8–9, 9; including 2 inner verticals; 4–5, 4 outer verticals; and 2–3, 3 postorbitals. Clypeus with 11–18, 15 setae. Tentorium 86–121, 109 μm long; 10–13, 12 μm wide. Palpomere lengths (in μm): 25–33, 30; 28–38, 33; 68–81, 76; 76–91, 86; 119–167, 142. Third palpomere with 3–5, 4 sensilla clavata; longest 15–20, 19 μm long.

Wing. VR 1.12–1.19, 1.17. Brachiolum with 2 setae. R with 11–17, 15 setae; R1 with 8–15, 11 setae; R4+5 with 24–31, 27 setae. Squama with 2–3, 3 setae. Anal lobe weakly developed.

Thorax. Scutum without tubercle. Antepronotals absent; dorsocentrals 7–10, 9; acrostichals 10–12, 11; prealars 1–3, 2. Scutellum with 4–6 (3) setae, uniserial.

Legs. Scale of foretibia 21–27 (2) μm long, with rounded apex. Spur of midtibia 48–59, 54 μm long; including 12–16, 14 μm long comb. Spur of hind tibia 70 (1) μm long, including 21 (1) μm long comb. Width at apex of foretibia 43–48 (2) μm; of midtibia 43–48, 45 μm; of hind tibia 54 μm. Lengths (in μm) and proportions of legs as in Table 3 .

Abdomen. Tergite II with 14–30 (3), III with 15–25 (3), IV with 17–24 (3), V with 16–31 (3), VI with 14–22 (3), VII with 13–14 (3), VIII with 10–13 (3) setae.

Genitalia ( Figs 23–24 ). Gonocoxapodeme well sclerotized, slightly sinuous, reaching basis of dorsomesal lobe. Gonocoxite with 2–3, 2 setae. Tergite IX with 13–18, 16 setae. Segment X with 3–4, 4 setae on each side. Postgenital plate triangular. Cercus 81–89, 83 µm long. Dorsomesal lobe large, subquadrangular. Ventrolateral lobe small, bluntly triangular. Seminal capsules ovoid, 76–89, 83 µm long. Notum 43–56, 48 µm long.

Pupa. (n = 1–2). Total length 6.53 mm long.

Coloration. Exuviae pale with margins of wing sheath, leg sheath and thorax light brown.

Cephalothorax. Cephalic tubercles ( Fig. 25 ) bluntly triangular, 114 µm long, 182 µm wide. Frontal setae 24– 27 µm long. Thorax ( Fig. 26 ) 1.59–2.00 mm long.

Abdomen ( Fig. 27 ). Tergite I bare; tergite II–VI with anterior band of very strong shagreen and extensive median field of finer shagreen; tergite VII with anterior band of strong shagreen, antero-median field of finer shagreen and two small postero-lateral patches of fine shagreen; tergite VII with wide, anterior band finer shagreen. Pedes spurii A well developed on segment IV. Pedes spurii B well developed on segment II. Tergite II with 37–80 hooks. Anal comb ( Fig. 28 ) with strong apical tooth and 2–3 lateral teeth.

Abdominal setation. Segment I without L setae; segment II–IV each with 3 non-taeniate L setae; segments V– VII each with 3 taeniate L setae; segment VIII with 4 taeniate L setae. Fringe of anal lobe with 13 taeniae.

Larva (n = 1–2). Total length not measurable (thorax and abdomen lost). Head capsule 253 (1) µm long. Postmentum 134–137 µm long.

Coloration. Head capsule yellowish brown with postoccipital margin, teeth of mentum and mandible brownish black.

Head. Antenna as in Figure 31 . Length of antennal segments (in µm): 30, 15, 8, 10, 4. Blade 40 µm long. AR 0.83. Lauterborn organs 3 µm long. Pecten epipharyngis ( Fig. 32 ) consisting of 3 platelets, both median and lateral platelets with 3 teeth each. Premandible 48–61 µm long. Mandible ( Fig. 30 ) 91–99 µm long, with serrate inner margin, with apical tooth and 3 inner teeth. Seta subdentalis well developed; seta interna with about 4 branches. Mentum ( Fig. 29 ) 68–71 µm wide, with 8 pairs of mental teeth; first and third lateral teeth much lower than median and second lateral teeth. Ventromental plate 70–72 µm wide, distance between plates 24–26 µm.

Distribution. The species is known from Rio Tarumã, Amazonas State, Northern Brazil and Santa Catarina State, South Brazil.

Remarks. This species was described originally from black water streams in the Amazon State. But the assumption that the immatures occur in streams was based on the type locality and the author failed to mention the possibility of the species occurring in phytotelmata.

The larva will key to dichotomy 7 in Trivinho-Strixino (2011), but does not go further due to the tapering posterior margin of the ventromental plates and the mentum having 16 teeth.

Figures

FIGURES 17 – 22. Polypedilum (s. str.) solimoes Bidawid-Kafka, 1996, male. 17 – head. 18 – wing. 19 – thorax. 20 – spur of foretibia. 21 – hypopygium, dorsal view. 22 – hypopygium with tergite IX and anal point removed, dorsal view left, ventral view right.

FIGURES 23 – 24. Polypedilum (s. str.) solimoes Bidawid-Kafka, 1996, female. 23 – genitalia, ventral view. 24 – tergite IX.

FIGURES 25 – 28. Polypedilum (s. str.) solimoes Bidawid-Kafka, 1996, pupa. 25 – frontal apotome. 26 – thorax. 27 – abdominal tergites. 28 – anal comb.

FIGURES 29 – 32. Polypedilum (s. str.) solimoes Bidawid-Kafka, 1996, larva. 29 – mentum. 30 – mandible. 31 – antenna. 32 – pecten epipharyngis.

Tables

TABLE 3. Lengths (in μm) and proportions of legs of Polypedilum (s. str.) solimoes Bidawid-Kafka, 1996, female (n = 4, if not otherwise stated).

	fe	ti	ta1 ta2 ta3	ta4
p1	561–729, 664	318–449, 393	68–842 (2) 393–542 (2) 262–374 (2)	187–262 (2)
p2	524–701, 627	439–589, 533	281–365 (2) 140–187 (2) 94–122 (2)	47–56 (2)
p3	608–785, 711	496–645, 598	514 (1) 262 (1) 252 (1)	140 (1)
	ta5	LR	BV SV	BR
p1	43–48 (2)	1.88–1.91 (2)	1.59–1.62 (2) 1.39–1.45 (2)	3.7–3.8 (2)
p2	28–37 (2)	0.63–0.64 (2)	3.93–4.03 (2) 3.43–3.53 (2)	1.7–4.4 (2)
p3	47 (1)	0.80 (1)	2.77 (1) 2.78 (1)	7.4 (1)