Caladomyia carolensis, Trivinho-Strixino, Susana, 2012

Trivinho-Strixino, Susana, 2012, A systematic review of Neotropical Caladomyia Säwedal (Diptera: Chironomidae), Zootaxa 3495, pp. 1-41 : 22-26

Caladomyia carolensis sp. n.

( Figs 42–48 )

Type material. Holotype: male, BRAZIL, SP, São Carlos, Córrego do Espraiado (21° 58’ S, 47° 53’ W), xi/2009, leg. S. T. Strixino (C2–12, LEIA /UFSCar). Paratypes: 1 male, as holotype (C2–13, LEIA /UFSCar); 1 male with pupal exuviae, as holotype except Córrego Canchim (21° 56’ S, 47° 54’ W), 27/vi/2001, leg. F. O. Roque (C2–14, LEIA /UFSCar); 1 female with pupal and larval exuviae, as holotype (C2–15, LEIA /UFSCar); 1 female, as holotype C2–16, LEIA /UFSCar); 3 pupal exuviae in the same slide, as holotype (C2–17, LEIA /UFSCar); 1 larva, as holotype (C2–18, LEIA /UFSCar); 2 larvae in the same slide, as holotype (C2–19, LEIA /UFSCar).

Etymology. The name carolensis refers to the locality where the species were collected, São Carlos city.

Diagnostic characters. Caladomyia carolensis sp. n. differs from all other species of the genus by the combination of the following characters. Adult male: thorax, abdomen, antenna and legs yellowish; AR 0.61; fore leg ratio 3.05; hypopygium with anal tergite bands of Y-type, fused part 44 µm long; anal point 35 µm long with posterior ending divided in three protrusions; ventromedian projection of anal point very long; bars 34 µm long, reaching far beyond distal corner of anal point; digitus 36 µm long, reaching well beyond posteromedian margin of superior volsella. Adult female: AR 0.55; wing membrane as male; genitalia with somewhat curved GcaVIII; GcIX with 1 seta; GpVIII simple, rounded. Pupa: frontal apotome wrinkled, without cephalic tubercle; thorax with weak granulation close to anterior median suture; tergite III–IV with longitudinal paired band of long spines obliquely divergent posteriorly; T V–VI with paired patches of short multiple spines. Larva: Antennal pedestal with prominent spur; clypeal S3 plumose emerging from a double base.

Description

Male (n = 2)

Dimensions. Small, length about 2.20 mm.Wing length 1.28–1.35 mm.

Coloration. Head, thorax and abdomen and legs yellowish-green.

Head. Eyes ratio 2.35. Frontal tubercles 9–11 µm long. Antennal flagellum 756–813 µm long; AR 0.61–0.62. Palpomere 2–5 lengths: 31–37, 106–118, 100–112,194–206 µm. Temporal setae 5, uniserial. Clypeus with 10 setae.

Thorax. Ac 12, biserial beginning near antepronotum; Dc 5–6; Pa 1; Scts 4. Scutal tubercle absent. Each halter with 4 setae.

Wing. Width 0.31 mm. VR 1.19–1.36. Membrane macrotrichia restricted to distal portion of the wing.

Legs. Front tibia with one short white spur. Mid and hind tibiae with two black combs, each one with one spur. Lengths and proportions as in Table 8.

fe ti ta1 ta2 ta3 ta4 ta5 LR p1 687– 744 281–312 912–950 450 375– 381 287–300 125–144 3.04–3.25 p2 656–662 494–512 306–319 144–162 100 56 43–44 0.59–0.64 p3 649–700 625–631 437–444 269–275 250 150 75–81 0.69–0.70 Hypopygium ( Fig. 42 ). Anal tergite near 74 µm long, with 2 distal setae. Anal tergite bands Y-shaped; fused part about 41–44 µm long. Anal point 31–37 µm long, with slightly concave margins; lateral margin bearing 2 setae. AnPR 2.6–3.4. Anal point bars 34–40 µm long, their tips reaching beyond apex of anal point; AnPBR 0.9. Superior volsella somewhat quadrangular, near 30 µm large, with 5 dorsal setae and 1ventral on anterior part of median margin. Digitus 29–36 µm long, reaching well beyond median corner of superior volsella; tip of digitus truncate. Inferior volsella bent in an S-shape. Median volsella short (11 µm long), with 2 lamelliform and 4 simple setae. Gonostylus 67µm long. Hypopygium ratio 0.80–0.83.

Female (n = 2)

Dimension and coloration. Length 1.65–1.71 mm. Wing length 1.12–1.15 mm. Coloration as male.

Head. Eyes bare, with little dorsomedian extension. Eyes ratio 3.4. Antennal flagellum slightly shorter than palp; Fm lengths 1–5: 36, 44; 56, 67; 46, 56; 61, 69; 81, 118 µm. Palpomere 2–5 lengths: 30; 94, 106; 88, 106; 187, 189 µm. Frontal tubercles not discernible. Temporal 4–5 setae. Clypeus with 15–16 setae.

Thorax. Ac 12 biserial, beginning near antepronotum; Dc 6; Pa 1; Scts 4. Scutal tubercle absent. Each halter with 4–5 setae.

Wing. Width 0.31–0.37 mm. VR 1.07–1.14. 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 combs with two black combs, each one with 2 unequal one spur. Lengths and proportions as in Table 9.

fe ti ta1 ta2 ta3 ta4 ta5 LR p1 595–625 250–275 781–900 400–412 331 269 131 3.12–3.27 p2 575–594 450–481 262–269 119–125 75–87 50–56 44–50 0.56–0.58 p3 575–606 481–569 350–369 212–219 200 100–144 62–69 0.60–0.64 Genitalia ( Fig. 43 ). Sternite VIII bearing 16 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, 57 µm long, 1.6 times as long as seminal capsules. Seminal capules ovoid, near 45 µm long, without neck. Spermathecal duct very long and forming a loop, with enlarged portion near the seminal capsules connection. GcaVIII somewhat curved, running diagonally to posteromedian corner of SVIII. GcIX with 1 seta.

Pupal exuviae (n = 2)

Dimensions. Length of abdomen: male near 2.1 mm, female 2.0 mm.Wing sheath 731 µm. Coloration yellow.

Cephalothorax. Frontal setae elongate, slender, 88–101 µm long; cephalic tubercles absent. Thoracic horn slender and smooth. Thorax with weak granulation close to median suture. Wing sheath with short nose. Thoracic setation on both sides: 3 precorneals (Pc1–3), 119, 103, 103 µm long, and 2 lateral antepronotals (LAps1–3). Dc 1–4 present and situated in two groups widely separated; distance between D C1–D C3 137–165 µm.

Abdomen. Tergite I bare; II with central transverse field of fine shagreen; T III–IV with longitudinal paired bands of long spines diverging posteriorly; T V–VI with paired patches of short multiple (bifid or trifid) spinules ( Figs 44 and 45 ). Hook row continuous, occupying near 1/2 width of segment II. Segment VIII with posterolateral combs consisting of 4–5 large marginal teeth and 20–25 overlapping ventral teeth ( Fig. 46 ). Anal lobe with 20–22 taeniate setae and 2 dorsal taeniae. Segments II–IV with 3 L setae; segmentV–VI with 3 taeniae; segment VII with 4 taeniae; segment VII with 5 taeniae.

4th instar larva (n = 4)

Dimensions. Small, total length 3.1–3.7 mm.

Head. Width 168–194 µm, length 237–262 µm; IC 0.71–0.74. Antenna with 5 segments, placed on pedestal, 61–73 µm long with prominent spur; basal segment 1.7 times as long as flagellum, with basal ring organ and small seta in distal 1/3; segment 2 as long as segments 3–5; Lauterborn organs large, pedicels, including LO, 64–67 mm long, proximal half sclerotized ( Fig. 47 ). Clypeal (S3) with double base, each one branched ( Fig. 48 ). Pecten epipharyngis of 3 distally serrated scales. Mentum 64 µm long, with pale median tooth slightly notched laterally, 5 pairs of lateral teeth brown, decreasing in size laterally. Ventromental plates 70 µm long.

Abdomen with anal tubules, short. Posterior parapods with simple hooks.

Remarks. The main characteristics that differentiate the males of C. carolensis sp. n. from other species are the very long bars and the shape of the digitus. The patterns and distribution of spines on abdominal tergite of the pupa are similar to those of C. bruneola sp. n. and C. kapilei sp. n. The prominent spur of antennal pedestal and the shape of clypeal seta (S3) distinguish the larvae from other species of the genus.

The larvae live on bottom sediments of small forested streams in central area of state of São Paulo.

Figures

FIGURES 42 – 43. Caladomyia carolensis sp. n. 42. Male hypopygium, dorsal (left), ventral (right). 43. Female genitalia, ventral.

FIGURES 44 – 48. Caladomyia carolensis sp. n. Pupa. 44. Abdominal tergites. 45. Spines of tergites III – VI. 46. Posterolateral comb of sabdominal egment VIII. Larva. 47. Antenna. 48. Clypeal seta S 3.