Caladomyia yara, Trivinho-Strixino, Susana, 2012

Trivinho-Strixino, Susana, 2012, A systematic review of Neotropical Caladomyia Säwedal (Diptera: Chironomidae), Zootaxa 3495, pp. 1-41 : 36-38

Caladomyia yara sp. n.

( Figs 75–82 )

Type material. Holotype: male with pupal exuviae, BRAZIL, SP, Luiz Antônio, Lagoa do Diogo, Estação Ecológica de Jataí (21° 37’ S, 47° 48’ W), leg. S. T. Strixino, 28/vii/2003 (C1–20, LEIA /UFSCar). Paratypes: 1 male with pupal exuviae (C1–21, LEIA /UFSCar), 1 female with pupal and larval exuviae (C1–22, LEIA /UFSCar), 1 female with pupal exuviae (C1–25, LEIA /UFSCar), 2 larvae in the same slide (C1–23, LEIA /UFSCar), 2 larvae in the same slide (C1–24, LEIA /UFSCar), as holotype.

Etymology. From the indigenous Tupi language “ Yara ” meaning the goddess of the waters. The name is to be regarded as a noun in apposition.

Diagnostic characters. Caladomyia yara sp. n. differs from all other species of the genus by the combination of the following characters. Adult male: thorax and abdomen green yellowish; AR 0.75; fore leg ratio 2.90; hypopygium with anal tergite bands of Y-type, fused part 31µm long; anal point 30 µm long with posterior ending divided in three protrusions; bars 6 µm long; digitus well developed, not reaching beyond posteromedian margin of superior volsella. Adult female: AR 0.59; wing membrane as male; genitalia with somewhat curved GcaVIII; GcIX with 1 seta; GpVIII simple, rounded. Pupa: frontal apotome wrinkled, cephalic tubercles absent; thorax with weak granulation close to anterior median suture; tergite III–V with paired patches of short spines anteriorly, flanked by points laterally. Larva: Clypeal S3 with base plumose; posterior parapods with some serrate claws.

Description

Male (n = 2)

Dimensions. Small, length about 2.1–2.4 mm. Wing length 1.21–1.25 mm.

Coloration. Head yellow, flagellum and maxillary palp pale brown. Thorax, abdomen and legs yellow.

Head. Eyes ratio 4.5. Frontal tubercles short, 6 µm long. Antennal flagellum 800–840 µm long; AR 0.74–0.76. Palpomere 2–5 lengths: 29, 88–91, 97–108, 169–170 µm.Temporal setae 7, uniserial. Clypeus with 8–9 setae.

Thorax. Ac 3; Dc 4–5; Pa 1; Scts 2. Halteres with 4 setae.

Wing. Width 0.38 mm. VR 0.80–0.84. Membrane macrotrichia restricted to distal portion of the wing.

Legs. Front tibia with short white spur. Mid and hind tibiae each with two black combs, each one with one spur. Segment lengths in µm and proportions as in Table 13.

Fe ti ta1 ta2 ta3 ta4 ta5 LR p1 632 – 47 285 –294 823–853 394–397 320–323 260–265 117–120 2.88–2.90 p2 624–676 457–485 264–279 103–118 82–88 59 47–49 0.57–0.63 p3 618– 641 603–612 412–426 235 218–220 132–147 88 0.67–0.70 Hypopygium ( Fig. 75 ). Anal tergite 68 µm long, with 2 distal setae. Anal tergite bands Y-shaped; fused part about 31–35 µm long. Anal point with slightly concave margins; dorsolateral margin bearing 2 setae, vertical ventromedian part with 1 distal and 1 more proximal pair of setae. AnPR 1.6–2.0. Anal point bars short, 6–8µm long, near the middle of anal point, their tips not reaching apex of anal point; AnPBR 2.6–3.8. Superior volsella with 6 dorsal setae and 2 on anterior part of median margin. Digitus 27–28 µm long, not reaching beyond posteromedian corner of superior volsella. Median volsella short (8–10 µm long), with 2 lamelliform and 6 simple setae. Gonostylus 63 µm long. Hypopygium ratio 0.9.

Female (n = 2)

Dimension and coloration. Length 1.67–1.76 mm. Wing length 1.15 mm. Coloration as male.

Head. Eyes bare, with little dorsomedian extension. Eyes ratio 3.8. Antennal flagellum slightly shorter than palp; Fm lengths 1–5: 37–38, 34–38, 44–49, 50–52, 100–103 µm. Palpomere 2–5 lengths: 25–31, 80–94, 81–88, 150–161 µm. Frontal tubercles short, 3µmlong. Temporal 6 setae. Clypeus with 10 setae.

Thorax. Ac 5 biserial, beginning near antepronotum; Dc 3; Pa 1; Scts 2. Scutal tubercle absent.

Wing. Width 0.30–0.40 mm. VR 1.33. Macrotrichia covering all cells and veins except M and basal third of M1+2. R 2+3 not indistinct; R4+5 ends proximal of M 3+4.

Legs. Fore tibia with one short spur; mid and hind tibial with two black combs each one with one spur. Lengths and proportions as in Table 14 .

Genitalia. Sternite VIII bearing 14 setae distributed regularly; SVIII form a large floor under anterior part of vagina; posteromedian contour of SVIII rounded. GpVIII not divided, and densely covered with caudolateral microtrichia. Notum, 45 µm long, 0.7 times as long as seminal capsules. Seminal capsules ovoid, near 60 µm long, without neck. Spermathecal duct very long and forming a loop. GcaVIII somewhat curved, running diagonally to posteromedian corner of SVIII. GcIX with 1 seta.

Pupa exuviae (n = 4)

Dimensions. Small, abdomen length near 2.0 mm (male), 1.7 mm (female). Coloration yellow brown. Wing sheath 769–800 µm.

Cephalothorax. Frontal setae elongate, slender, 62–80 µm long; cephalic tubercles absent. Thoracic horn slender and smooth. Thorax with weak granulation close to median suture; scutal tubercle absent. Wing sheath with short nose ( Fig. 76 ). Thoracic setation: Present on both side 3 precorneals (Pc1–3) and 2 lateral antepronotals (LAps1–3). Dc1–4 present and situated in two groups widely separated; distance between D C1–D C3 169–194 µm.

Abdomen. Tergite I bare; T II with central transverse field of fine shagreen; T III–V with paired patches of short spines anteriorly, flanked by points laterally; T VI with central transverse field of fine shagreen; T VII–VIII without shagreen; T IX with patches of fine punctuation anteriorly ( Fig. 77 ). Hook row continuous, occupying 1/3 width of segment II. Segment VIII with posterolateral combs consisting of 4–5 marginal and 7–10 overlapping ventral teeth ( Fig. 78 ). Anal lobe with 19–22 taeniae and 2 dorsal taeniae. Segments II with 3 L setae; segments III with 2 L setae and 1 taenia; segment IV–VI with 3 taeniae; segment VII with 4 taeniae; segment VIII with 5 taeniae.

4th instar larva (n = 4)

Dimensions. Small, total length 1.4–2.9 mm.

Head. Width 219–231 µm, length 269–291 µm; IC 0.78–0.85. Clypeal (S3) simple with base plumose ( Fig. 79 ). Antenna 5-segmented ( Fig. 80 ), placed on prominent pedestal (bearing a distinct apical tooth); basal segment slightly longer than flagellum, with basal ring organ and small seta in proximal 1/2; segment 2 unsclerotized distally, shorter than segments 3–5; Lauterborn organs large, pedicels including LO, 46–48 µm long, proximal half sclerotized. Mandible with pale dorsal tooth; apical and two inner teeth brown. Mentum ( Fig. 81 ) with pale median tooth slightly notched laterally, 5 pairs of lateral teeth brown, decreasing in size laterally.

Abdomen with anal tubules 250 µm long, curved down (short). Posterior parapods, in addition to simple hooks, with some serrate claws ( Fig. 82 ).

Remarks. The short anal point bars and the shape of the superior volsella are the main characteristics that differentiate the male of C. yara sp. n. from other species. The patterns and distribution of spines on abdominal tergite distinguish the pupa of this species from others. The presence of some serrate claws in the posterior parapods approximates the larvae of C. yara with C. friederi , differing of this by the length of the pedicels and 3th antennal segment.

The larvae were collected associated to aquatic macrophyte in oxbow lakes of Mogi-Guaçu river floodplain.

Figures

FIGURES 75 – 82. Caladomyia yara sp. n. Male. 75. Hypopygium, dorsal (left), ventral (right). Pupa. 76. Thorax, lateral. 77. Abdominal tergites. 78. Posterolateral comb of abdominal segment VIII. Larva. 79. Antennal pedestal and clypeal setae S 3. 80. Antenna. 81. Mentum and ventromental plates. 82. Posterior parapod claws.

Tables

TABLE 14. Lengths (in μm) and proportions of legs of C. yara sp. n., female.

fe	ti	ta1	ta2	ta3	ta4	ta5	LR
p1 531–538	218–238	769	337	294	225	118–125	3.50
p2 469–519	375–400	212–238	88–94	69	31–37	25–30	0.60
p3 506–518	394–425	300–325	187	175	87	69	0.76