Araucoderus gloriosus (Alexander, 1920)

Ovtshinnikova, Olga G., Galinskaya, Tatiana V. & Lukashevich, Elena D., 2018, Skeleton and musculature of the male abdomen in Tanyderidae (Diptera, Nematocera) of the Southern Hemisphere, ZooKeys 809, pp. 55-77 : 57-59

Araucoderus gloriosus (Alexander, 1920) Figures 1A, B, 2, 3, 4

Material.

Chile, Nothofagus -dominated forest, on riparian vegetation. Alerce Andino National Park: Lenca River, 340 m asl (41°30'S, 72°37'W), 6-8.i.2014, 12-18.i.2015, D.E. Shcherbakov, E.D. Lukashevich, 8 males; Puyehue National Park: Anticura River near Anticura Waterfall, 400 m asl (40°40'S, 72°10'W), 14.i.2014, E.D. Lukashevich, 1 male; Chanlefu River at Aguas Calientes, 470 m asl (40°44'S, 72°18'W), 16.i.2014, D.E. Shcherbakov, 1 male; Huerquehue Natianal Park: near Tiquilco Lake, 780 m asl, (39°10'S, 71°44'W), 22.xii.2014, E.D. Lukashevich, 1 male; near La Junta, Rio Palena, 70 m asl, (43°49'S, 72°21'W), 5.i.2015, E.D. Lukashevich, 1 male. The specimens will be deposited in the Zoological Institute RAS, St-Petersburg, Russia.

Exoskeleton.

The male terminalia were described in great detail by Madriz and Courtney (2016), so here we describe only the muscles; scanning electron micrographs of genitalia are published for comparison purposes (Figure 1A, B).

Musculature.

Thoracic muscles. One pair of tergal muscles, connecting thorax and medial part of tergite I; one pair of sternal muscles, connecting thorax and anterolateral margin of sternite II (Figure 2C).

Abdominal muscles. One pair of long intersegmental tergal muscles ITM1 connecting medial part of tergite I and medial part of tergite II (Figure 2C). Segments I–VII with wide, short tergosternal muscles (TSM1-TSM7) (Figure 2C). One pair of long symmetrical intersegmental sternal muscles ISM2 passing from anterior third of sternite II to anterior margin of sternite III. Two pairs of long symmetrical intersegmental tergal muscles (ITM2a,b) passing from posterior half of tergite II to anterior margin of tergite III; medial ITM2a slightly thinner and longer, lateral ITM2b slightly stronger but shorter (Figure 2A, C). Intersegmental tergal and sternal muscles on segments III–V with similar attachment sites as intersegmental muscles of segments II–III (Figure 2C). One pair of intersegmental tergal muscles ITM6 extending from tergite VI to tergite VII. One pair of intersegmental sternal muscles ISM6 extending from sternite VI to sternite VII. Intersegmental muscles ITM6 and ISM6 thinner than intersegmental muscles of previous segments; posterior sites of attachment of muscles ITM6 and ISM6 slightly displaced counterclockwise due to terminalia rotation (Figure 2C). One pair of long asymmetrical muscles ISM7 extending from middle of anterior part of sternite VII to left anterior margin of sternite VIII; posterior sites of attachment of muscles ISM7 displaced counterclockwise due to terminalia rotation (Figure 2B). Tergite VIII situated on left side of abdomen. One pair of asymmetrical muscles ITM7 extending from tergite VII to tergite VIII. Right muscle ITM7 long, extending from middle of tergite VII to posterior part of tergite VIII. Left muscle ITM7 short, extending from posterior margin of tergite VII to posterior part of tergite VIII. Posterior sites of attachment of muscles ITM7 displaced counterclockwise due to terminalia rotation (Figure 2B, C).

Pregenital muscles. Paired short asymmetrical muscles M18: right muscle M18 long, connecting middle of right side of sternite VIII to narrow sclerotized stripe or hypandrium between gonocoxite bases; left wide short muscle M18 connecting middle of left side of sternite VIII to narrow sclerotized stripe between gonocoxite bases (Figures 2B, 3C). Narrow sclerotized stripe between gonocoxite bases interpreted as hypandrium according to attachment sites of muscles M18. Paired short, wide and slightly asymmetrical muscles M19 extending from center of tergite VIII to anterior margin of epandrium (Figure 3B).

Tergosternal muscles. Paired, wide symmetrical M5 connecting anterolateral parts of epandrium to lateral thickenings of dorsal bridge of paramere in the point of connection of pm db with gonocoxites (= gonocoxal apodeme) (Figures 3A, 4B, C). Lateral thickenings of dorsal bridge of paramere interpreted as gonocoxites according to attachment sites of muscles M5.

Muscles of the hypandrial complex. Paired long retractors M1+2 extending from anterior edges of gonocoxites to aedeagal condyle, and several muscle filaments of M1+2 extending from anterior edges of gonocoxites to posterior margin of dorsomedial element of paramere pm dme (Figure 4A, D). Paired long M23 extending from posterior edge of ejaculatory apodeme (dorsally) to membrane near aedeagus (Figure 4A, D). Paired wide protractors M30 extending from anterior half of ejaculatory apodeme (laterally) to anterior margin of gonocoxites (Figure 4A, B, D). Paired retractors M31 extending from posterior part of ejaculatory apodeme to medial part of dorsal bridge of paramere pm db (Figure 4D). Paired long wide M27 extending from anterior part of gonocoxites to ligament near anterior margin of gonostyli (Figure 4B). Paired long wide M28 extending from medial part of gonocoxites to condyle of gonostyli (Figure 4B).

Muscles of the epandrial complex. Paired short wide M3 extending from most of inner epandrium surface to hypoproct (X sternite) (Figure 4C). Paired thin M7 extending from posterolateral parts of hypoproct to cerci (Figure 4C).