Pseudosmittia simplex Strenzke et Thienemann

Ferrington Jr, Leonard C. & Saether, Ole A., 2011, A revision of the genera Pseudosmittia Edwards, 1932, Allocladius Kieffer, 1913, and Hydrosmittia gen. n. (Diptera: Chironomidae, Orthocladiinae) 2849, Zootaxa 2849 (1), pp. 1-314 : 163-167

Pseudosmittia simplex Strenzke et Thienemann

( Figs. 58 , 59 )

Pseudosmittia simplex Strenzke et Thienemann, 1942: 368 .

Material examined: AUSTRIA: Lower Austria, Lunz, Lunzer Mittersee, Osthang ober Hohenstein , holotype male, 13.vi.1941, K. Strenzke, on two slides (6P697, 6P699)( NMS) , allotype female, as holotype except 14.vi.1941, paratypes, 1 male, 1 female, 5 pupae, 12 larvae, as holotype ( NMS) , 1 male, 1 female placed between plastic strips in pin labeled "Typus", as holotype ( IRSN) .

Diagnostic characters: The male imago can be separated from other members of the genus by lacking the superior volsella, having a very low inferior volsella and accessory lobe, long anal point, and virga appearing to consist of fused spines with lateral spinules not observable. The female imago have reduced median lobes of the antepronotum, third palpomere with 5–6 sensilla clavata and no non- marginal setae on the costa between FR and the apex of R 4+5. The pupa differs from all other known pupae of the Pseudosmittia complex by lacking spinules on tergal and sternal conjunctives. The larva differs from other members of the genus by lacking claws on the posterior parapods combined with having an antennal blade about as long as the width of the basal antennal segment.

Male imago (n = 1–2)

Total length 2.04 mm. Wing length 1.24 mm. Total length/wing length 1.65. Wing length/length of profemur 2.93. Coloration brown.

Head. AR 0.63. Terminal flagellomere 279 µm long. Temporal setae 5, consisting of 3 inner verticals and 2 outer verticals. Clypeus with about 4 setae. Tentorium 91 µm long, 21 µm wide. Stipes 96 µm long, 27 µm wide. Palpomere lengths (in µm): 27, 37, 62, 59, 110. Third palpomere with 5 strong and lanceolate sensilla clavata.

Thorax. Antepronotal lobes reduced medially, lateral setae obscured. Dorsocentrals 8, acrostichals 2, prealars 3. Scutellum with 5 setae.

Wing ( Fig. 58 A ). VR 1.26. Anal lobe absent. Costal extension 71 µm long. R 4+5 ending above apex of M 3+4; Cu 1 curved. Brachiolum with 1 seta, other veins bare.

Legs. Spur of front tibia 37 µm long, spurs of middle tibia 21 µm and 16 µm long, of hind tibia 37 µm and 16 µm long. Width at apex of front and middle tibiae each 25 µm, of hind tibia 33 µm. Comb of 10 setae, 18–23 µm long. Lengths and proportions of legs as in Table 35.

Hypopygium ( Fig. 58 D ). Anal point 39–53 µm long; tergite IX with 13 setae; laterosternite IX with 3 setae. Phallapodeme 64–69 µm long; transverse sternapodeme 64–75 µm long, oral projections barely indicated. Virga ( Fig. 58 C ) appearing to consist of fused spines, no lateral spinules observed. Gonocoxite 142–144 µm long; superior volsella absent; inferior volsella and accessory lobe very low and reaching to 0.60–0.62 and 0.71–0.73 gonocoxite length, respectively. Gonostylus 64–66 µm long; megaseta 10–11 µm m long. HR 2.14–2.25, HV 3.19.

Female imago (n = 1–2)

Total length 1.82 mm. Wing length 0.99–1.03 mm. Total length/ wing length 1.77. Wing length/length of profemur 3.35.

Head. AR 0.32. Flagellomeres not fusiform, no apical strong seta. Length (in µm) of flagellomeres: 66–69, 45– 48, 41–46,43,62–64. Temporal setae 3–5, including 2–3 inner verticals and 1–2 outer verticals. Clypeus with 6 setae. Tentorium 78 µm long, 9 µm wide. Stipes 75 µm long, 21 µm wide. Palpomere lengths (in µm): 14–18, 30–31, 48–55, 43–71, 71–78. Third palpomere with 5–6 lanceolate sensilla clavata, fourth palpomere with 1 sensillum clavatum. Coronal suture nearly complete.

Thorax. Antepronotal lobes reduced medially, lateral setae not observed. Dorsocentrals 9, acrostichals 2, prealars 3. Scutellum with 4 setae.

Wing ( Fig. 58 B ). VR 1.20–1.32. Anal lobe absent. Costal extension 78–80 µm long. R 4+5 ending above apex of M 3+4; Cu 1 sinuate. Brachiolum with 1 seta, R with 4–6 setae, R 1 with 2, R 4+5 with 2–3 setae, other veins bare. No nonmarginal setae on the costa between FR and the apex of R 4+5.

Legs. Spur of front tibia 23 µm long, spurs of middle tibia 16 µm and 9 µm long, of hind tibia 30 µm and 15 µm long. Width at apex of front tibia 25 µm, of middle tibia 27 µm, of hind tibia 32 µm. Comb of 12 setae, 21–30 µm long. Lengths and proportions of legs as in Table 36.

Abdomen. Tergite VII with 16, VIII with about 10 setae. Sternite VII with 6, VIII with 15 setae. Genitalia. Gonocoxite without caudal extension, with 1 long and 5 weak setae. Tergite IX divided, with altogether

16 setae. Cercus 55 µm long. Apodeme between gonocoxite and tergite IX 80 µm long. Seminal capsule dark, ovoid;

85 µm long, excluding 18 µm long neck, 71 µm wide, microtrichia not observed. Notum 86 µm long.

Pupa (n = 5, except when otherwise stated)

Total length 1.91–2.50, 2.15 mm. Exuviae uncolored, only with slight brownish-yellow tinge on cephalothoracic margins.

Cephalothorax. Frontal apotome smooth. Frontal setae very weak, 14–16 µm (2) long All setae 10–25 µm long. Apex of antepronotum with 2–7, 4 distinct spinules. Distance between Dc 1 and Dc 2 9–43, 18 µm; between Dc 2 and Dc 3 43–64, 55 µm; between Dc 3 and Dc 4 9–23, 15 µm.

Abdomen ( Fig. 59 A–B ). Tergite I bare, T II–IX with nearly even shagreen covering most of segments except apicolateral area on T VII. Sternites I–V and IX bare, VI–VIII with broad anterior shagreen. All conjunctives bare. Anal setae absent. Genital sac bare, male genital sac overreaching segment by 75 µm (1).

Fourth instar larva (n = 8–10, except when otherwise stated)

Total length 2.22–3.47, 2.80 mm (4). Head capsule length 0.20–0.23, 0.22 mm.

Head. Antenna as in Fig. 59 C . Length of antennal segments (in µm): 14–15,14; 3–5.5, 4; 1.5–2.5, 2; 6.5–7, 7. AR 0.93–1.15, 1.03. Basal antennal segment 15–17, 15 µm wide; blade 16–23, 20 µm long; accessory blade 5.5–8, 7 µm long. Sensilla basiconica 4.5–6.5, 5 µm long (6). Apical style of second segment 5.5–6.5, 6 µm long (6). Labrum and epipharyngeal area as in Strenzke and Thienemann (1942 figs. 24, 25). Premandible ( Fig. 59 D ) 51–56, 53 µm long. Mandible ( Fig. 59 E ) 94–101, 97 µm long; with 3 inner teeth, seta subdentalis 6.5–8, 7 µm long (4); seta interna absent. Maxilla as in Strenzke and Thienemann (1942 fig. 28). Mentum as in Fig. 59 F , median tooth 21 µm wide (3), ventromental plate 7–9 µm wide on flattened mentum. Seta submenti apically plumose. Postmentum 62–80, 73 µm long.

Abdomen ( Fig. 59 G ). Anterior parapods completely fused with no longer claws. Posterior parapods strongly reduced, without claws. Dorsal anal tubules 23–32 µm long (2), 23–27 µm wide (2). Ventral anal tubules 32–46 µm long (2). 34–41 µm wide (2).

Third instar larva (n = 2)

Total length 1.71–1.80 mm. Head length 0.10–0.11 mm.

Head. Length of antennal segments (in µm): 8–10; 3–4; 1.5; 3.5–4.5. AR 1.57–1.67. Basal antennal segment 10– 11 µm wide, blade 13.5–14.5 µm long, accessory blade 3.5–4.5 µm long; sensilla basiconica 3.5 µm long. Apical style of second segment 3.5 µm long. Premandible 30 µm long. Mandible 53–57 µm long. Postmentum 37–39 µm long. Abdomen. Anal tubules 21–30 µm long, 21–27 µm wide.

Distribution

The species is known from Austria, Germany, and The Netherlands.

Figures

FIGURE 58. Pseudosmittia simplex Strenzke et Thienemann, imagines. A—male wing; B—female wing; C—virga; D— hypopygium, left dorsal aspect, right ventral aspect.

FIGURE 59. Pseudosmittia simplex Strenzke et Thienemann, immatures. A—male pupa, posterior tergites; B—female pupa, posterior segments, lateral view; C—larval antenna; D—larval premandible; E—mandible; F—mentum; G—larval abdomen, posterior apex.