Clinotanypus caritus, Oliveira & Silva & Trivinho-Strixino, 2013

Oliveira, Caroline Silva Neubern de, Silva, Fabio Laurindo da & Trivinho-Strixino, Susana, 2013, Four new species of Clinotanypus Kieffer, 1913 (Diptera: Chironomidae: Tanypodinae) from Neotropical region, Journal of Natural History (J. Nat. Hist.) 48 (5 - 6), pp. 317-343 : 319-325

Clinotanypus caritus sp. nov.

( Figures 1–3 )

Type material

Holotype male with pupal and larval exuviae, BRAZIL, SP, São Carlos , Mayaca reservoir, 21 ◦ 58 ′ 02 ′′ S, 47 ◦ 33 ′ 01 ′′ W, 835 m above sea level (a.s.l.), September 2010, S. T. Strixino . Paratype pharate male with larval exuviae, BRAZIL, BA, Santa Terezinha , Serra da Jibóia, 12 ◦ 51 ′ 00 ′′ S, 39 ◦ 30 ′ 00 ′′ W, 800 m a.s.l., 19 September 2009, D. P. Cordeiro .

Etymology

From Latin, caritus , meaning lacking, devoid of, or poor, referring to the lack of shagreen at the base of scar in the pupa.

Diagnostic characters

Clinotanypus caritus sp. nov. differs from other Neotropical species by the combination of the following characters. Male: dark brown notum, TIX with 21 setae and anal point bilobed. Pupa: base of scar without shagreenation, segment VII with six taeniae and anal lobe 769–825 µm long. Larva: mandible broad and row of setae at the lateral outer margin present; palp segment 114–118 µm long.

Descriptions

Adult male (n = 1)

Dimensions. Total length 4.68 mm. Wing length 2.31 mm. Total length / wing length 2.03. Wing length / length of profemur 2.36.

Coloration. Head, pedicel, antenna and maxillary palp brown. Thorax with microtrichia, dark brown notum and pale brown anepisternum and pre-episternum. Wing membrane transparent without spots, veins brown and with macrotrichia on C and R 1 veins. Legs pale brown with dark brown bands as in Figure 1C–E . Abdomen and hypopygium brown.

Head ( Figure 1A ). Antenna with 14 flagellomeres, AR 1.99, flagellum 1438 µm long. Temporal setae 32, multiserial ( Figure 1A ). Eyes bare, with dorsomedian extension containing four terminal facets. Tentorium 237 µm long, stipes not measurable. Clypeus 110 µm long, 120 µm wide at largest part, bearing 17 setae. Cibarial pump with anterior margin concave, 310 µm long. Palpomere lengths 1–5 (in µm): 105; 97; 83, 213; 257.

Thorax ( Figure 1B ). Antepronotum with 16 lateral setae. Acrostichals biserial; dorsocentrals 44, merging with the acrostichals posteriorly; prealars 63; supraalars 1; scutellars 18; postnotals 48; posterior anepisternals II 8; epimerals 1; preepisternals divided into two groups, group I with 28 setae and group II with 22 setae, as in Figure 1B .

Wing ( Figure 1C ). Width 0.79 mm long. Costa 2.17 mm long, produced beyond R 4+5. R 1 with 31 setae. VR 0.87. WW 0.34. Brachiolum with 1 seta. Squama with 29 setae.

Legs ( Figure 1D–I ). Foreleg: tibia with one apical spur 74 µm long ( Figure 1G ). Mid leg: tibia with two apical spurs 63; 57 µm long ( Figure 1H ); tarsomeres 1–3 with two pseudospurs 35–46, 39 and 37 µm long, respectively. Hind leg: tibia with two apical spur 89 and 60 µm long ( Figure 1I ); tarsomeres 1–3 each with one pseudospur 42, 48 and 37 µm, respectively; double comb present. All legs with claws pointed. Pulvilli absent. Lengths and proportion of leg segments as in Table 1.

Hypopygium ( Figure 1J ). Tergite IX with irregular row of 21 dorsal setae. Anal point bilobed. Phallapodeme long and wide, 115 µm long. Sternapodeme curved anteriorly, 145 µm long. Gonocoxite conical, 242 µm long, with slightly concave inner margin. Gonostylus simple, 103 µm long; megaseta 14 µm long. HR 2.45. HV 4.54.

Pupa (n = 2)

Coloration. Exuviae pale brown with brown spots. Thoracic horn mostly brown.

Cephalothorax ( Figure 2A ). Frontal apotome 346 (1) µm wide. Wing sheath 1.5 (1) mm long and 0.60 (1) mm wide. Thoracic horn 527–545 µm long and 169–181 µm wide, with few spinules on the surface; plastron plate large, 246–285 µm long ( Figure 2A ); aeropyle tube 243–300 µm long. Respiratory atrium tubular. Narrow basal lobe present.

Abdomen ( Figure 2B–D ) 3.80–5.00 mm long. Tergites I with shagreen consisting of slightly arched serial rows of groups 2–3 spinules ( Figure 2C ); TII–VII with sparse and solitary spinules ( Figure 2D ). T I with pigmented scar, 175–179 µm long, without shagreenation at the base. Dorsal chaetotaxy as in Figure 2B. T VII with 6 taeniae. T VIII with 5 taeniae. Anal lobe as in Figure 2B , 769–825 µm long and 625 (1) µm wide, with two anal macrosetae. Genital sac smaller than anal lobe, 300–350 µm long. GS / AL 0.36–0.46.

Fourth instar larva (n = 2)

Coloration. Head pale yellow, postoccipital margin brown; antenna pale yellow; apical tooth of mandible brown; ligula pale yellow. Abdomen pale yellow, procercus, anal setae and posterior parapod claws pale yellow.

Head ( Figure 3A ). Length 668 (1) µm, 643 (1) µm wide; cephalic index 0.96 (1). Chaetotaxy as in Figure 3A .

Antenna. Length 645–761 µm, A 1 600–703 µm long, with ring organ placed 521–618 µm from base, A 2 43–45 µm long. AR 12–13.

Maxilla ( Figure 3B ). Palp segment 114–118 µm long and 14 µm wide, with ring organ 60–64 µm from base, A 1 / P 1 5.26–5.93, A 2 / P 1 0.37–0.38.

Mandible ( Figure 3C ). Length 104–112 µm, with 3 lateral setae. A 1 / MD 5.82–6.27. Row of setae at the lateral outer margin present.

Mentum and M appendage ( Figure 3 Da,b). Dorsomentum with 4–6 pairs of lateral teeth; pseudoradula uniformly granulate; lateral teeth of M appendage absent or present.

Hypopharyngeal complex. Ligula 95 (1) µm long, anterior margin slightly concave. Paraligula pectinate, 60 (1) µm long. Pecten hypopharyngis with 22 teeth equal in size. Body. With lateral fringe. Anterior parapods with simple claws. Procercus 177–227 µm long, 60 µm wide, with 14 anal setae 655–745 µm long. L / W 2.9–3.79. Supraanal seta 550 (1) µm long. Anal tubules not measurable. Posterior parapod apex with 10 simple and 5 hook-shape claws.

Ecology

The larva of Clinotanypus caritus was collected in a small reservoir associated to the aquatic macrophyte Mayaca fluviatilis .

Figures

Figure 1. Clinotanypus caritus sp. nov.: adult male. (A) Head, frontal view. (B) Thorax. (C) Wing. (D–F) Legs, P1 (D), P2 (E), and P3 (F). (G–I) Tibial spurs of P1 (G), P2 (H) and P3 (I). (J) Hypopygium with tergite IX, left: ventral aspect, right: dorsal aspect.

Figure 2. Clinotanypus caritus sp. nov.: pupa. (A) Thoracic horn. (B) Tergites chaetotaxy, anal lobe and male genital sac. (C, D) Shagreen pattern on abdominal segments, (C) Segment I, (D) Segment II–VII.

Figure 3. Clinotanypus caritus sp. nov.: larva. (A) Head with chaetotaxy, left: dorsal aspect, right: ventral aspect. (C) Maxillary palp detail. (C) Mandible. (Da, b) a. Mentum and M appendage, b. variation.