Culicoides lacustris Ronderos, 1990

Anjos-Santos, Danielle, Funes, Amparo, Spinelli, Gustavo R. & Ronderos, María M., 2014, The immatures of Culicoides lacustris Ronderos (Diptera: Ceratopogonidae), Zootaxa 3881 (6), pp. 583-590 : 584-589

publication ID

https://dx.doi.org/10.11646/zootaxa.3881.6.7

publication LSID

lsid:zoobank.org:pub:834E0692-9944-46C9-9D3D-F9D759858B18

DOI

https://doi.org/10.5281/zenodo.6135355

persistent identifier

https://treatment.plazi.org/id/586AD34E-7F71-9C71-FF08-FC84CE4FF7F1

treatment provided by

Plazi

scientific name

Culicoides lacustris Ronderos, 1990
status

 

Culicoides lacustris Ronderos, 1990

(Figs. 1–26)

Culicoides lacustris Ronderos, 1990: 116 (male, female; Argentina); Spinelli & Ronderos, 1994: 60 (Neuquén records); Borkent & Spinelli, 2000: 37 (in Neotropical catalog); Ronderos & Spinelli, 2002: 94 (Chubut and Santa Cruz records); Spinelli et al., 2005: 140 (in key; Argentina); Borkent & Spinelli, 2007: 71 (in Neotropical catalog); Muzón et al., 2010: 113 (localities in the Somuncura plateau); Borkent, 2014: 89 (in world catalog).

Culicoides venezuelensis: Spinelli & Wirth, 1985: 64 (misident., in part., record from Bariloche).

Fourth instar larva (Figs. 1–10). Coloration whitish in life. Head capsule (Figs. 1–3) yellowish, moderately elongate, apex slightly bent ventrally; HL 0.375 mm, HW 0.15 mm, HR 1.08. Setae simple, moderately thin, medium-sized to elongate, chaetotaxy as in Figs. 1–3. Antenna short. Labrum (Figs. 1–3) shorter than greatest basal width, with 3 pairs of anterolateral sensilla styloconica (Figs. 4 –5, 8); palatum (Figs. 3, 5) with 2 pairs of closelyspaced sensilla trichoidea (Fig. 4–5); messors (Fig. 5) small, thin, gently sclerotized, scopae present (no visible for detailed description). Maxilla (Fig. 3, 7) with papillae; maxillary palpus (Fig. 4 –5, 7– 8) medium-sized, cylindrical, with 4 subapical papillae, two medium-sized and two short, and one triangular-shaped lateral lobe; galeolacinia (Fig. 4 –5, 7) with lacineal sclerite 2 bearing long, thin seta, and one pore (Fig. 4 –5, 7). Mandible (Figs. 3 –4, 6– 7) stout, heavily sclerotized, medium-sized, hooked, curved, with broad base, apical tooth large, pointed, with long setae on basal portion near hypocondyle, one insertion of seta on ectal margin, fossa mandibularis on ectal surface (Fig. 6); ML 0.108 mm, MW 0.036 mm. Hypostoma (Figs. 2 –5, 8) with rounded, mesal, smooth elevation, lateral margin serrate, with 5 truncate lateral teeth. Epipharynx LAW 0.051–0.055 (0.054, n= 3) mm, DCW 0.011–0.018 (0.016, n= 3). Thoracic pigmentation uniformly pale. Caudal segment (Figs. 9–10) with 6 pairs of setae, four long, stout, other two thin.

FIGURES 1–10. Culicoides lacustris Ronderos , larva (SEM). 1, head capsule, lateroventral view (chaetotaxy); 2, head capsule, ventral view (chaetotaxy); 3, head capsule, frontoventral view (chaetotaxy); 4, head capsule, anteroventral view; 5, detail of head capsule, ventral view; 6, detail of mandible; 7, detail of mouthparts, lateral view; 8, details of head capsule, ventral view; 9, caudal segment, ventrolateral view (chaetotaxy); 10, caudal segment, lateral view (chaetotaxy). Antennae (AN); collar (CO); fossa mandibularis (MF); galeolacinia (GL); hypostoma (HY); labrum (LB); lacinial sclerite 1 (LC 1); lacinial sclerite 2 (LC 2); mandible (MD); maxilla ( MX); maxillary palpus (MP); messors (MS); palatum (PL); sensilla basiconica (SB); scopae (SC); sensilla styloconica (ss); sensilla trichoidea (st). Head capsule chaetotaxy: j, collar pits; n, anterolateral pit; o, parahypostomal setae; p, posterior perifrontal setae; q, postfrontal setae; s, anterior perifrontal setae; t, prefrontal setae; u, mesolateral setae; v, posterolateral setae; w, anterolateral setae; x, paranntenal setae; y, ventral setae. Caudal segment chaetotaxy: o, outer setae; i, inner setae; l 1, first lateral setae; l 2, second lateral setae; v, ventral setae.

Female Pupa ( Figs. 12, 14–17 View FIGURES 11 – 18 , 19– 25 View FIGURES 19 – 25 ). Exuviae general coloration pale brown. Flagellum appressed against lateral margin of face. Total length 2.90–3.18 (3.02, n= 4) mm. Length of cephalothorax 1.23 (n= 4) mm, width 0.72–0.78 (0.75, n= 4) mm. Dorsal apotome ( Fig. 12 View FIGURES 11 – 18 ) without ventral line of weakness, dorsomedial tubercle and central dome, slightly wider than long, distal margin nearly straight, smooth except for few small spinules; disc surface and anterior margin covered by stout rounded spinules; raised areas bearing 2 dorsal apotome sensilla ( Fig. 12 View FIGURES 11 – 18 ), as follows: DA- 1 -H moderately elongate, thin seta, located on well developed tubercle, DA- 2 -H campaniform sensillum at tubercle base; DAL 0.144–0.168 (0.16, n= 3) mm; DAW 0.156–0.18 (0.16, n= 3) mm; DAW/ DAL 0.93–1.25 (1.04, n= 3). Cephalothorax rectangular, surface covered with small spinules; antenna extending posteriorly to various points along anterior margin of wing; mouthparts ( Fig. 22 View FIGURES 19 – 25 ) with mandible and lacinia well developed; palpus extending to posterolateral margin of labium; labium separated medially by labrum; apex of labrum rounded. Cephalothoracic sensilla ( Fig. 19–20 View FIGURES 19 – 25 ) as follows: one anteriomedial AM- 1 -T medium-sized, thin seta ( Fig. 20 View FIGURES 19 – 25 ); 2 dorsolateral cephalic sclerite sensilla ( Fig. 19 View FIGURES 19 – 25 ): DL- 1 -H medium-sized, stout seta, DL- 2 -H short, stout seta on prominent, rounded tubercle; 3 anterolaterals ( Fig. 19 View FIGURES 19 – 25 ): AL- 1 -T, AL- 3 -T short, stout setae, AL- 2 -T long, thin seta, all sensilla on slightly rounded tubercle; clypeal labrals ( Fig. 22 View FIGURES 19 – 25 ): CL- 1 -H medium-sized, thin seta, CL- 2 -H short, thin seta; oculars ( Fig. 22 View FIGURES 19 – 25 ): O- 1 -H long, thin seta, O- 3 -H, medium-sized, thin seta, O- 2 -H campaniform sensillum. Respiratory organ ( Figs. 14 View FIGURES 11 – 18 , 20 View FIGURES 19 – 25 ) smooth, medium-sized, slightly curved with pointed apex, wider at base, 28–30 closely abutting pores laterally and apically; pedicel stout, P 0.024 mm, 0.133–0.166 (0.155, n= 3) mm; RH length 0.144–0.18 (0.156, n= 4) mm, RH wide 0.06 (n= 4) mm; P/H 0.133–0.166 (0.155, n= 3); 5 dorsal setae ( Figs. 15-21 View FIGURES 11 – 18 View FIGURES 19 – 25 ) and SA- 2 -T ( Fig. 21 View FIGURES 19 – 25 ): D- 1 -T minute seta, D- 2 -T short, stout seta, D- 3 -T campaniform sensillum, D- 4 -T very long, thin seta, D- 5 -T minute seta. Metathoracics ( Fig. 23 View FIGURES 19 – 25 ): M- 1 -T medium-sized, thin seta, M- 2 -T-M- 3 - T campaniform sensilla, M- 3 -T near anterior margin. Abdominal segments with smooth integument, scarce spicules spread on anterior and posterior portions; each segment without pigmentation pattern. First abdominal segment ( Fig. 24 View FIGURES 19 – 25 ) with setae as follows: 3 anteromesal setae, D- 2 -I short, stout seta, D- 3 -I long, thin seta, D- 7 -I campaniform sensillum; 3 posterior setae, D- 4 -I campaniform sensillum, D- 8 -I short, thin seta, D- 9 -I medium-sized, thin seta; L- 1 -I medium-sized, thin seta, L- 2 -I-L- 3 -I minute setae. Fourth segment ( Fig. 16 View FIGURES 11 – 18 , 25 View FIGURES 19 – 25 ) with sensilla as follows: D- 1 -IV minute seta, D- 2 -IV short seta, D- 3 -IV medium-sized seta, D- 3 -IV thinner than D- 2 -IV; D- 4 -I without setae, D- 5 -IV minute seta, D- 7 -IV minute seta, D- 8 -IV short, stout seta, D- 9 -IV medium-sized, thin seta; V- 5 -IV minute seta, V- 6 - IV medium-sized, thin seta, V- 7 -IV short seta, all on rounded small tubercles; L- 1 -IV minute seta, L- 2 -IV, L- 4 -IV short setae, L- 4 -IV shorter than L- 2 -IV, L- 3 -IV medium-sized, thin seta, all on triangular tubercles. Segment 9 ( Fig. 17 View FIGURES 11 – 18 ) approximately 1.6 times as long as greatest width, length 0.264–0.276 (0.27, n= 4) mm, width 0.17–0.18 (0.174, n= 4) mm; posteriorly directed spicules restricted to narrow anterior band, not connected to central patch of spicules; mesal spicules patch not extending to posterolateral terminal processes, terminal processes closely approximated basally, moderately elongated, subparallel with pointed, dark tips; ventral surface of processes with spicules on each side of midline, D- 5 -IX-D- 6 -IX campaniform sensilla.

Male pupa ( Fig. 11, 13, 18 View FIGURES 11 – 18 ). Similar to female with usual sexual differences. Total length 3.03–3.25 (3.13, n= 4) mm. Exuviae pale brown. Dorsal apotome ( Fig. 13 View FIGURES 11 – 18 ) with DAL 0.144–0.168 (0.156, n= 2) mm; DAW 0.144–0.168 (0.15, n= 2) mm, DAW/ DAL 0.86–1.08 (0.97, n= 2). Respiratory organ ( Fig. 11 View FIGURES 11 – 18 ): RO length 0.144–0.204 (0.17, n= 5) mm, RO width 0.048–0.06 (0.050, n= 5) mm; pedicel length 0.024 (n= 4) mm, P/RO 0.060–0.076 (0.069, n= 4). Cephalothorax ( Fig. 11 View FIGURES 11 – 18 ) length 1.23–1.26 (1.248, n= 5) mm, width 0.72–0.81 (0.76, n= 5) mm. Segment 9 ( Fig. 18 View FIGURES 11 – 18 ) length 0.288–0.312 (0.3, n= 5) mm, width 0.18–0.24 (0.197, n= 5) mm; terminal processes ( Fig. 18 View FIGURES 11 – 18 ) length 0.084–0.096 (0.09, n= 5) mm, width 0.024–0.03 (0.0252, n= 5) mm, ventral genital lob moderately long, slightly globose, extending just beyond posterior margin, surface wrinkled.

Distribution. Argentina, in Nothofagus forests and steppes of Neuquén, Río Negro, Chubut and Santa Cruz provinces.

Bionomics. Immatures of Culicoides lacustris were found in a 3.14 m 2 pond located in a semi-arid steppe area of the Chubut province, which is connected to a “mallin”, a typical Patagonian wetland fed by groundwater, with intermittent flooding regime and devoid of fishes ( Epele & Archangelsky, 2012). The climate in this region is generally dry, cold and windy. This pond presents clayey sediment, bordered by shrubs and grass steppe on one side and by the road on the other ( Fig. 26). This site is used as pasture and water supply for sheep and domestic horses.

A total of 14 pupal exuviae, two pupae and three larvae were collected in the site, at 2:00– 2: 30 pm, with a temperature of 20 °C. The water temperature was 17 °C and the pH 7.5. Only one larva took 12 days to reach the pupal stage, but did not reach the adult stage. Two larvae died after 10 days. Larvae were kept at a temperature ranging between 18 and 21 °C.

The medium-sized “o” and “i” setae of the pupal caudal segment could represent a good adaptation to the environment where it was captured.

Discussion. The larva of C. lacustris is very similar to the Neotropical congener C. venezuelensis Ortiz and Mirsa by virtue of the labrum, the hooked mandible, the maxillary palpus cylindrical and the caudal segment with 6 pairs of setae (4 long, 2 thinner ones). However, C. venezuelensis differs by its yellowish brown coloration in vivo, the palatum has 3 pairs of sensilla trichoidea (one major, one minor ), a pair of sensilla chaetica immediately underneath, 5 well developed scopae and the mandible apical tooth is more elongated and pointed.

The pupae of C. venezuelensis is clearly disting from that of C. lacustris by the respiratory organ long, thin and straight with rounded apex, annulated on basal ½, dark brown except central portion paler, and bearing 5–6 apical and 3–4 lateral pores. Moreover, the exuvia of C. venezuelensis is yellowish brown, and the apex of the dorsal apotome is blunt and its surface is covered by rounded, pointed, strong and anteriorly directed tubercles.

Specimens examined. Argentina, Chubut, Provincial Route 12, “El Tropezón”, 42 ° 47 ’44, 2’’S; 70 ° 51 ’ 07,7’’W, 781 m, 13.xii. 2012, Anjos-Santos, D. leg, 2 ♂, 2 ♀, with pupal exuviae, 5 pupal exuviae ♂, 5 pupal exuviae ♀, 1 larva. All the specimens were collected as larvae and pupae, and were reared in laboratory.

Specimens examined by SEM: same data, 2 larvae.

DAL

Dalhousie University

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Diptera

Family

Ceratopogonidae

Genus

Culicoides

Loc

Culicoides lacustris Ronderos, 1990

Anjos-Santos, Danielle, Funes, Amparo, Spinelli, Gustavo R. & Ronderos, María M. 2014
2014
Loc

Culicoides lacustris

Borkent 2014: 89
Muzon 2010: 113
Borkent 2007: 71
Spinelli 2005: 140
Ronderos 2002: 94
Borkent 2000: 37
Spinelli 1994: 60
Ronderos 1990: 116
1990
Loc

Culicoides venezuelensis:

Spinelli 1985: 64
1985