Trichocorixa mendozana Jaczewski
Creators: name: Konopko, Susana Amanda
name: Mazzucconi, Silvia Ana
name: Bachmann, Axel Oscar
Publisher: name: Zenodo
Year: 2011
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Corixidae
Trichocorixa
Trichocorixa mendozana

description: Trichocorixa mendozana Jaczewski
(Figs. 1–27, Tables 1–3)
Material examined. ARGENTINA: Buenos Aires Province, Laguna Chasicó, XI–1983, Genise J. coll. (FCEyN – UBA) (nymphs: instar IV, 11 specimens; V, 23); Buenos Aires Province, Salinas Chicas, at the road-side to Laguna Chasicó, IV–2010, Konopko S.A. coll. (FCEyN – UBA) (10 oviposited eggs; nymphs: instar I, 12 specimens).
Egg (Fig.1). EL: 0.62–0.74 mm. EW: 0.37–0.42 mm. ML: 0.03–0.04 mm. SL: 0.05 mm. Shape oval (Fig. 1), EL/EW: 1.47–1.80, flattened at one side, with a very short stalk (Fig. 1). Color yellow, micropylar process and stalk transparent. Surface ornamented by irregular interlocking smooth hexagons.
First instar (Figs. 2–3, 6, 12, 15–16, 21–22)
Color. Ground color testaceous with dark markings. Head testaceous with dark markings, except ecdysial line and ventral and lateral surfaces testaceous. Eyes reddish brown. Rostrum testaceous except basally darker. Antennae testaceous with pale setae. Pronotum dark with two pale markings on each side of the segment. Meso- and metanotum testaceous with dark markings. Thoracic pleurae and sterna testaceous. Legs testaceous. Abdominal terga testaceous with dark markings; scent glands reddish brown on segments IV and V; abdominal sternites testaceous, except last segment with a rounded, middle, dark area. Conexivum testaceous.
Body. Suboval, BL/BW: 1.61–1.62. Measurements that characterize the body shape are shown in Table 1.
Head. Short, subrectangular, HL/HW: 0.24; anterior margin rounded; Y-shaped ecdysial line visible; with trichobothria and some long, stout and short, slender setae in frontal view. S/eW: 2.50–3.10. OI: 3.00–3.26. HW/BL: 0.46–0.48. Rostrum short, with three transverse sulcations (N= 3). Antenna: AL/BL: 0.10; two-segmented; segment II longer than segment I, A1:A2= 0.29:1.00; A1 subrectangular; A2 subcylindrical; A2 width/length: 0.51–0.56. A1 and A2 dorsal surface bare; A1 ventral surface with one preapical campaniform sensillum; A2 ventral surface with one prebasal campaniform sensillum, a set of short, slender spines and two short, stiff on the apical half of the segment (Fig. 6).
Thorax. Pronotum visible, subrectangular and short, anterior margin convex at middle, lateral margins convex, and posterior margin concave at middle. Mesonotum posterior margin slightly convex at middle. Metanotum posterior margin straight at middle. Ecdysial line visible on pro-, meso- and metanotum. Thoracic terga with few short slender setae; meso- and metanotum with one lateral spine on both sides of each segment. PL/BL: 0.21. Pro-, meso- and metapleura with short, slender setae. Pro-, meso- and metasternum posterior margin concave at middle. Thoracic sterna with few short, slender setae. Meso- and metathoracic spiracles small and rounded, located ventrally, near posterior margin of each segment. Meso- and metathoracic wing pads absent. Prolegs short, L1/BL: 0.34– 0.35; femur shorter than tibiotarsus, FE1/ TITA: 0.76–0.79 (Fig. 12). Procoxa short, subconical; anterior and posterior surfaces with few short, slender setae. Protrochanter short; anterior surface with some short, slender setae (two basal), and three basal campaniform sensilla; posterior surface with two basal campaniform sensilla; posteroventral surface with three short spines. Profemur short and subrectangular (Fig. 12); anterior surface with four spines (three short, one long), and two short, slender, prebasal setae; anterodorsal surface with five long spines (the apical one longest); anteroventral surface with one short, preapical spine; posterior surface with some short, slender setae; posterodorsal surface with one long, slender seta. Tibiotarsus spoon-shaped, TITA width/length: 0.36–0.38 (Fig. 12); anterior surface with nine long setae in dorsal, 16–17 setae in upper and 13 bristles in lower rows, tibial comb represented by two spines (one short, one long), and two short spines behind the tibial comb; anterodorsal surface with two spines; anteroventral surface with two short spines; inner surface with 9–10 long slender setae; posterior surface with some short and long, slender setae. One short, slender and falcate claw. Mesolegs long and slender; L2/BL: 0.77–0.81 (Figs. 15–16); femur longest, tarsus longer than tibia; FE:TI:TA=1.00:0.44–0.51:0.49–0.56. Mesocoxa short, subconical (Fig. 15); anterior surface with some short, slender setae; posterior surface bare. Mesotrochanter short (Fig. 15); anterior surface with some short, slender setae (two basal), and three basal campaniform sensilla; anteroventral surface with three short spines; posterior surface with three basal campaniform sensilla and one short spine. Mesofemur subcylindrical, straight (Figs. 15–16); anterodorsal surface with nine spines (two apical longest), and chloride cells (not illustrated); anteroventral surface with seven spines (two apical longest), and chloride cells (not illustrated); posterodorsal surface with one apical, short spine; posteroventral surface with five spines (one short, four long) on the basal half of the segment, and chloride cells (not illustrated) (Fig. 16). Mesotibia subcylindrical, straight (Figs. 15–16); anterior surface with a row of six spines; anterodorsal surface with two long, slender spines (one prebasal, one preapical); anteroventral surface with a row of five spines (the apical one longest); posterior surface with eight spines (seven short, one apical long), and six long, slender setae; posterodorsal surface with three short spines; posteroventral surface with tibial comb represented by one long slender spine. Mesotarsus subcylindrical, straight (Figs. 15–16); anterodorsal surface with one long, slender seta and six spines; anteroventral surface with eight spines; posterior surface with a row of five spines (four short, one apical long); posterodorsal surface with four spines (three short, one preapical long), one prebasal campaniform sensillum, and seven long, slender setae. Two long, slender, falcate claws of different length. TA2/CL1: 0.71–0.82; TA2/ CL2: 067–0.79. Metalegs long and slender; L3/BL: 0.89–0.93; tarsus longest, tibia shorter than femur; FE:TI:TA=0.71–0.76:0.63:1.00 (Figs. 21–22). Metacoxa large, subconical; anterior surface with one short spine (Fig. 21); anterodorsal surface with chloride cells (not illustrated); anteroventral surface with one long, apical spine; posterior surface with some short, slender spines. Metatrochanter short (Fig. 21); anterior surface with some short, slender setae (two basal), and three basal campaniform sensilla; anteroventral surface with three short spines; posterior surface with three basal campaniform sensilla and two short, slender spines. Metafemur slightly curved and flattened anteroposteriorly (Figs. 21–22); anterior surface with eight–nine short spines in three areas (upper, one (apical); middle, four; lower, three–four); anterodorsal surface with eight spines, and chloride cells (not illustrated); anteroventral surface with chloride cells (not illustrated); posterodorsal surface with two short, apical spines (Fig. 22); posteroventral surface with four short spines, and chloride cells (not illustrated). Metatibia subcylindrical, straight, TI3 width/length: 0.31–0.35 (Figs. 21–22); anterodorsal surface with five short spines; anteroventral surface with six spines (five short, one apical long); posterior surface with seven short spines and three long, slender, prebasal setae; posterodorsal surface with eight spines; posteroventral surface with three short spines and tibial comb represented by two long, slender spines (Fig. 22). Metatarsus slightly curve and flattened anteroposteriorly; TA3 width/length: 0.12–0.15 (Figs. 21–22); anterior surface with eight–nine spines; anteroventral surface with 14–15 swimming hairs; posterodorsal surface with 14 spines (13 short, one preapical long, slender), 21 swimming hairs and four long, slender setae; posteroventral surface with 15 spines. Two long, slender, straight claws of different length. TA3/CL1: 1.89-2.00; TA3/CL2: 1.85–1.96.
Abdomen. Ecdysial line visible on segment I. Posterior margin of segment I straight dorsally and ventrally, segments II–VII concave dorsally and ventrally, segment VIII from slightly concave to straight dorsally and ventrally (Figs. 2–3). Segment III, only the two scent gland openings are distinct; segments IV–V, the bean-shaped scent glands and their openings are distinct (Fig. 2). G3/D3, G4/D4 and G5/D5: 2. Spiracles small and rounded, located latero-ventrally near posterior margin (segment I) or located ventrally near anterior margin (segments II– VIII). Terga with few short slender setae and chloride cells. Lateral spines of the abdominal segments on right/left sides: I, 0/0; II–III, 1/1 short; IV, 1/1 long; V, 3/3 short, 1/1 long; VI, 2/2 short, 2/2 long; VII, 1/1 short, 3/3 long; VIII, 3/3 short, 5/5 long (Fig. 2). Sterna with few short, slender setae and chloride cells. Central spines of urosternites: I–IV: 0; V: 2 short; VI–VII: 2 long; VIII: 2 short (Fig. 3).
Second and third instars. No specimens were available for study.
Fourth instar (Figs. 4, 7–8, 13, 17–18, 23–24)
Similar to first instar except for the following features:
Color. Rostrum testaceous except basally and apically darker. Prosternum testaceous with dark markings on posterior margin of the segment. Posterior half of the mesonotum dark, with dark pubescence. Metatibia testaceous except anterior and posterior surfaces basally and apically darker. Conexivum with dark markings on posterior margin of each segment.
Body. Elongate, BL/BW: 1.77–1.88. Measurements that characterize the body shape are shown in Table 1.
Head. HL/HW: 0.49–0.55; with chloride cells in frontal view; posterior margin with long, slender setae laterally and with short, apically serrate setae medially. S/eW: 1.14–1.50. OI: 1.19–1.50. HW/BL: 0.42–0.45. Rostrum with six transverse sulcations (N= 3). Antenna: AL/BL: 0.17–0.19; A1:A2= 0.29–0.30:1.00; A2 width/length: 0.26–0.30; A1 with a lateral protuberance (Figs. 7–8); A2 with a slightly notch on the basal fifth of the segment; A1 dorsal surface with short, slender setae; A2 dorsal surface with short and long, slender setae, and lanceolate, truncate ended setae; A2 ventral surface with six short, stiff spines on apical half, and ventral margin with short, slender setae (Figs. 7–8).
Thorax. Pronotum totally hidden by head; posterior half with short, slender setae; posterior margin with short and long, slender setae (not exposed). Meso- and metathoracic wing pads present. Meso-, metathoracic (distally) wing pads and hardly the anterior third of mesonotum with short, slender setae; metanotum with few short, slender setae and one short, lanceolate seta on both sides of the segment (in some specimens); posterior margin of setose area of mesonotum and internal margins of wing pads with short and long, lanceolate setae, respectively (the ones from the mesonotum not reaching the anterior margin of the metanotum medially); posterior and external margins of the wing pads with long, slender setae (Fig. 4). PL/BL: 0.28–0.29. Mesothoracic spiracles like the ones on the abdominal segment I, located dorsally; metathoracic spiracles like the abdominal ones and smaller than the mesothoracic ones, located ventro-laterally. Mesothoracic wing pads reaching the posterior third of the pterothorax; metathoracic wing pads surpassing the posterior margin of the urotergite I. Prolegs, L1/BL: 0.36–0.37; FE1/ TITA: 0.67–0.71 (Fig. 13). Procoxa anterior and posterior surfaces with abundant short, slender setae. Protrochanter anterior surface with abundant short, slender setae and five basal campaniform sensilla; posterior surface with abundant short, slender setae and three basal campaniform sensilla. Profemur (Fig. 13) anterior surface with a basal hydrophobic setose area covering the basal half of the segment, and six–seven spines; anterodorsal surface with four–five short spines (two apical); anteroventral surface without the preapical, short spine; posterior surface with a basal hydrophobic setose area covering more than the basal half of the segment. Tibiotarsus TITA width/length: 0.33– 0.37 (Fig.13); anterior surface with 12–14 long setae in dorsal, 34–37 setae in upper and 23–28 bristles in lower rows; tibial comb represented by four spines (two short, two long); anterodorsal surface with one-two spines; inner surface with 43–45 long, slender setae. Mesolegs L2/BL: 0.86–0.93; FE:TI:TA=1.00:0.49:0.40–0.44 (Figs. 17–18). Mesocoxa anterior and posterior surfaces with abundant short, slender setae (Figs. 17–18). Mesotrochanter (Figs. 17–18) anterior surface with abundant short, slender setae and five basal campaniform sensilla; anteroventral surface without the three short spines; posterior surface with abundant short, slender setae and seven basal campaniform sensilla. Mesofemur (Figs. 17–18) anterior surface with a basal hydrophobic setose area of short, slender setae; anterodorsal surface with 23–25 short and long spines; anteroventral surface with 26–29 short and long spines and 21–22 short, apically serrate spines; posterior surface with a basal transversal row of long, slender setae; posterodorsal surface without the apical, short spine; posteroventral surface with 33 spines (28 short, five long), and 16 short and long, slender setae. Mesotibia (Figs. 17–18) anterior surface with a row of 8–10 short spines and four campaniform sensilla; anterodorsal surface with the prebasal slender long spine, the preapical short spine and two slender setae (one short, one long); anteroventral surface with a row of 8–10 spines; posterior surface with four–five short spines, one prebasal campaniform sensillum, and 28 long, slender setae; posterodorsal surface with four short spines; posteroventral surface with 14 apically serrate spines, and tibial comb of four spines (zero–two apically serrate). Mesotarsus (Figs. 17–18) anterodorsal surface with three–four spines, two campaniform sensilla, and a short, slender seta; anteroventral surface with seven spines; posterior surface with a row of four–five spines; posterodorsal surface with four–five spines, one preapical campaniform sensillum, and 25 long, slender setae. TA2/ CL1: 0.82–0.86; TA2/CL2: 0.78–0.83. Metalegs L3/BL: 0.99–1.06; FE:TI:TA=0.72–0.73:0.69–0.70:1.00. Metacoxa anterior surface with abundant short, slender setae, some long, slender, apical setae and a preapical, central set of short and stout spines; posterior surface with short, slender setae. Metatrochanter anterior surface with abundant short, slender setae, and five basal campaniform sensilla; anteroventral surface with two long, slender spines; posterior surface with abundant short, slender setae and seven basal campaniform sensilla. Metafemur (Figs. 23–24) anterior surface with a basal hydrophobic setose area, reaching the apical third of the segment on ventral margin, with 15–16 short spines in three areas (upper: eight–nine; midle: four; lower: three); anterodorsal surface with five spines; posterior surface with a transverse, basal, row of long, slender setae; posteroventral surface with five short spines; ventral surface with 12–13 long, slender setae in the apical third of the segment. Metatibia (Figs. 23–24) TI3 width/length: 0.20–0.21; anterodorsal surface with seven–eight spines, one prebasal campaniform sensillum, and one short, slender, preapical seta; anteroventral surface with 11–14 short and long spines, and 22–24 long, slen- der setae; posterior surface with six spines, and 24 long, slender setae; posterodorsal surface with 11–12 spines, and four–six short, slender setae; posteroventral surface with 19–21 apically serrate spines and tibial comb represented by six spines. Metatarsus (Figs. 23–24) TA3 width/length: 0.18–0.19; anterior surface with eight spines; anteroventral surface with 17–19 spines, and 130–137 swimming hairs; posterodorsal surface with 30 short spines, 285 swimming hairs, and 10 long, slender setae; posteroventral surface with 31 short and long spines. TA3/CL1: 4.76– 5.55; TA3/CL2: 4.54–5.26.
Abdomen. Scent gland openings of segment III not distinct. G4/D4 and G5/D5: 2. Terga with abundant short, slender setae, some long, slender setae, and more chloride cells than in previous instar. Lateral spines of the abdominal segments on right/left sides: IV, 4/4 short, 2/2 long; V, 5/5 short, 5/5 long; VI, 5/5 short, 4/4 long; VII, 7/6 short, 6/6 long; VIII, 8/8 short, 7/7 long. Sterna with abundant short and long, slender setae, and without chloride cells. Urosternites I–VIII without central spines.
Fifth instar (Figs. 5, 9–11, 14, 19–20, 25–27)
Similar to fourth instar except for the following features:
Color. Posterior margin of head, inner and posterior margins of metathoracic wing pads darker.
Body. More elongate than previous instar. BL/BW: 2.01–2.34. Measurements that characterize the body shape are shown in Table 1.
Head. HL/HW: 0.43–0.54. S/eW: 0.95–1.05. OI: 0.90–1.11. HW/BL: 0.35–0.39. Rostrum with seven transverse sulcations (N= 3). Antenna: AL/BL: 0.15–0.17; A1:A2=0.27–0.30:1.00; A2 width/length: 0.21–0.22; A2 dorsal surface with one prebasal campaniform sensillum (Fig. 9); A2 ventral surface with 15 short, stiff spines on apical half, and ventral margin with abundant short, slender setae (Fig. 11).
Thorax. Mesonotum short, lanceolate setae on posterior margin of setose area reaching the anterior margin of the metanotum medially (Fig. 5). Metanotum with some short, lanceolate setae (Fig. 5). Posterior margins of meso- and metatoracic wing pads with long, lanceolate setae (Fig. 5). PL/BL: 0.29–0.32. Mesothoracic wing pads reaching the anterior margin of the urotergite III; metathoracic wing pads reaching anterior half of urotergite III. Prolegs (Fig. 14) L1/BL: 0.29–0.33; FE1/ TITA: 0.66–0.71. Protrochanter anterior surface with six basal campaniform sensilla; posterior surface with five basal campaniform sensilla. Profemur (Fig. 14) anterior surface with seven spines; anterodorsal surface with four short spines (two apical). Tibiotarsus (Fig. 14) TITA width/length: 0.36–0.39; anterior surface with 13–14 long setae in dorsal, 34–36 setae in upper and 25–28 bristles in lower rows, tibial comb represented by five spines (three short, two long); anterodorsal surface with one spine; inner surface with 50–55 long, slender setae. Mesolegs L2/BL: 0.73–0.86; FE:TI:TA=1.00:0.48–0.51:0.35–0.38. Mesotrochanter anterior surface with six basal campaniform sensilla; posterior surface with nine basal campaniform sensilla. Mesofemur anterodorsal surface with 22–25 short and long spines; anteroventral surface with 28–29 short and long spines and 40–42 short, apically serrate spines; posteroventral surface with 53–56 spines (45–46 short, 8–10 long), and 22–25 short and long, slender setae. Mesotibia (Figs. 19–20) anterior surface with a row of eight–nine short spines; anterodorsal surface with one long, slender seta; anteroventral surface with a row of eight–nine spines; posterior surface with four spines and 40–43 long, slender setae; posteroventral surface with 26–30 apically serrate spines, and tibial comb of five apically serrate spines. Mesotarsus anterodorsal surface with three campaniform sensilla; posterior surface with a row of five–six spines; posterodorsal surface with four spines and 38–40 long, slender setae. TA2/ CL1: 0.77–0.86; TA2/CL2: 0.74–0.83. Metalegs (Figs. 25–26) L3/BL: 0.83–0.97; FE:TI:TA=0.62–0.70:0.67– 0.70:1.00. Metatrochanter posterior surface with nine basal campaniform sensilla (Fig. 26). Metafemur (Figs. 25- 26) anterior surface with 28–29 short spines in three areas (upper, 18–19; middle: three; lower, seven–eight); anterodorsal surface with five–six spines; posteroventral surface with four–five short spines; ventral surface with 10–11 long, slender setae in the apical third of the segment. Metatibia (Figs. 25–26) TI3 width/length: 0.18–0.20; anterodorsal surface with six–seven spines; anteroventral surface with 20–24 short and long spines and 30–35 long, slen- der setae; posterior surface with 34 long, slender setae; posterodorsal surface with 12–14 spines and 9–12 short, slender setae; posteroventral surface with 19–24 apically serrate spines (Fig. 27), and tibial comb of seven–eight spines. Metatarsus TA3 width/length: 0.18; anterior surface with seven spines; anteroventral surface with 24–27 spines, and 330 swimming hairs; posterodorsal surface with 31–33 short spines, 435 swimming hairs, and 10–12 long, slender setae; posteroventral surface with 30 short and long spines. TA3/CL1: 6.67–7.70; TA3/CL2: 5.88– 7.14.
Abdomen. Lateral spines of abdominal segments on right/left sides: IV, 5/5 short, 2/2 long; V, 5/4 short, 4/5 long; VI, 7/8 short, 3/3 long; VII, 10/13 short, 4–5/4 long; VIII, 8–9/8 short, 7/7 long.
description: Published as part of Konopko, Susana Amanda, Mazzucconi, Silvia Ana & Bachmann, Axel Oscar, 2011, Description of the immature stages of Trichocorixa mendozana Jaczewski (Hemiptera: Heteroptera: Corixidae), pp. 47-61 in Zootaxa 3060 on pages 49-58, DOI: 10.5281/zenodo.200774