Pseudosmittia paraconjuncta (Hardy)

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 : 233-236

Pseudosmittia paraconjuncta (Hardy)

( Fig. 88 )

Orthocladius (Smittia) paraconjuncta Hardy, 1960: 143 .

Pseudosmittia paraconjuncta (Hardy) ; Cranston & Martin 1989: 262.

Pseudosmittia near restricta, Saether 1977 : fig. 60 D–F.

Material examined: USA: Hawaii: Oahu, Papukee Trail , 2 female paratypes, ix.1955, D. E. Hardy ( BBM) . South Carolina: Oconee County, Westminster, Star Route , Burt Collins Property , 1 female reared from pupa, 19.xi.1980, P. L. Hudson; Pickens County , Icoesgneene Forest , Clemson University, seep-stream, 1 female, 16.iii.1980, P. L. Hudson; Anderson County , Savannah River , Highway 181 bridge, moist banks, 2 larvae, 25.xii.1979; Anderson County , Savannah River , 4 mi below Hartwell Dam, moist bank, 1 pupa, 10 larvae, 30.ix.1980, P. L. Hudson; Heated ET, 2 female pupae, 18.iv.1973, 7.ii.1975, P. L. Hudson . Georgia: Hart County, Savannah River , 4 mi below Hartwell Dam, moist bank, 5 larvae, 30.ix.1980, P. L. Hudson ( ZMBN, UMSP) . CANADA: Ontario: Kenora , L. 239, 1 female 17–23.vii.1984, S. Mallory ( CNC) .

Diagnostic characters: The fused R 4+5 and costal extension, incomplete straight Cu 1 and seminal capsules with transverse striations makes P. paraconjuncta , P. fusivenosa and P. conjuncta easily separable from other known females of Pseudosmittia . Pseudosmittia paraconjuncta differs from P. conjuncta in having a strong apical seta on the antenna and an undivided tergite IX. It differs from P. fusivenosa at least by a lower VR of 1.54–1.67 as opposed to 2.00 for P. paraconjuncta . Pupa with a few spinules on thorax otherwise found only in P. simplex and in Hydrosmittia ruttneri ; tergal conjunctives II/III and VII/VIII, and sternal conjunctives III/IV, IV/V and VIII/IX all bare in female pupa. Larva with antennal blade extending beyond flagellum about as long as width of basal segment or less as in P. holsata , P. mathildae and P. simplex and shorter than in other known larvae of Pseudosmittia ; weak premandibular brush; seta subdentalis absent; anterior parapods with 5-8 longer claws; posterior parapods of larva with 3 claws.

Female imago (n = 5–7, except when otherwise stated)

Total length 1.03–1.38, 1.19 mm. Wing length 0.58–0.78, 0.66 mm. Total length/ wing length 1.75–1.90, 1.82. Wing length/length of profemur 3.29–3.60, 3.40. Coloration brownish black.

Head. AR 0.36–0.42, 0.38. Lengths (in µm) of flagellomeres: 43–57, 49; 34–37, 36; 37–43, 39; 32–39, 35; 56– 64, 59. Fifth flagellomere with 24–34 µm (3) long strong apical seta. Temporal setae 2–5,3; including 1–2, 1 inner verticals and 1–3, 2 outer verticals. Clypeus with 4–7, 6 setae. Tentorium 50–73, 64 µm long, 6–7, 7 µm wide. Stipes 48–62, 57 µm long, 14–24, 20 µm (4) wide. Palpomere lengths (in µm): 11–16, 14; 16–21, 18; 21–32, 27; 23–33, 27; 34–41, 37. Third palpomere with 2 sensilla clavata. Coronal suture absent or 16 µm (1) long.

Thorax. Median antepronotal lobes strongly reduced, lateral setae of antepronotum 1 (4). Dorsocentrals 4–7, 5; acrostichals 2; prealars 1–2, 2; no supraalar seta. Scutellum with 2 setae.

Wing ( Fig. 88 A ). VR 1.54–1.67, 1.60. Postcubitus not forked. Anal lobe absent, wing cuneiform. R 4+5 ending proximal to apex of M 3+4; Cu 1 straight, incomplete; R 4+5 and costal extension fused for 80–165, 106 µm in length. Brachiolum with 1 seta, costa between FR and apex of R 4+5 with 1–5, 2 non-marginal setae, fused part of costal extension and apical part of R 4+5 with 3–7, 5 non-marginal setae; R with 1–2, 1 seta; R 1 with 1–2, 1 seta; other veins bare.

Legs. Spur of front tibia 16–22, 20 µm long, spurs of middle tibia 9–11, 10 µm and 7–9, 8 µm long, of hind tibia 25–30, 27 µm and 10–14, 12 µm long. Width at apex of front tibia 16–18, 17 µm of middle tibia 18–23, 19 µm of hind tibia 25–32, 26 µm. Comb of 9–11, 10 setae, shortest setae 14–18, 16 µm long, longest setae 21–37, 27 µm long. Lengths and proportions of legs as in Table 63.

Abdomen. Tergite I bare; T II–VIII each with 4–8, 5 setae. Sternite I and II bare; S III and IV each with 2 setae; S V with 1–4, 2 setae; S VI and VII each with 2–4, 4 setae; S VIII with 12–23 setae.

Genitalia ( Fig.88 B–F ; Saether 1977, fig. 60 D–F). Gonocoxite low, adpressed, with 1–2, 2 strong and 1–3, 2 weak setae. Tergite IX undivided, with altogether 4–10, 7 setae. Cercus 32–39, 34 µm long. Apodeme against gonocoxite 41–73, 53 µm long. Seminal capsule 50–66, 57 µm long, 30–46, 37 µm wide, with distinct transverse striations, microtrichia not observed.

Spermathecal ducts with large bulbs before common opening. Notum 55–89, 77 µm long. Pupa (n = 3–4)Total length 1.17–1.67 mm. Exuviae colorless or with very slight yellowish tinge on margins.

Cephalothorax. Frontal apotome and wing sheath smooth, scutum with a few anterior spinules. Larger precorneals and ventral median antepronotals about 35–45 µm long; frontal setae, shorter precorneals and larger dorsocentral about 25–40 µm long; shorter dorsocentrals about 15 µm long. Distance between Dc 1 and Dc 2 30–43 µm, between Dc 2 and Dc 3 3–7 µm, between Dc 3 and Dc 4 5–16 µm.

Abdomen ( Fig. 88 G ). Tergite I bare; T II–VII with strong shagreen over most of tergite, stronger anteriorly and posteriorly; T VIII with bare preapical band; T IX with shagreen over most of segment, stronger medially. Sternites I– IV bare; S V–VIII with scattered spinules over whole sternites except bare medially and preapically on S VIII; S IX with caudolateral shagreen. Tergal conjunctives III/IV with 10–19, 14 spinules; IV/V with 15–35; V/VI with 22–33; VI/VII with 12–29, 20 spinules. Sternal conjunctives V/VI–VII/VIII with minute spinules; V/VI with 45–66, 53; VI/V with 63–80; VII/VIII with 10–29, 19. Anal segment without setae.

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

Total length 2.16–3.47, 2.88 mm. Head capsule length 0.15–0.19, 0.18 mm. Head capsule pale yellowish brown with only mentum and tip of mandible dark. Body probably whitish. Head. Antenna as in Fig. 88 H . Length of antennal segments (in µm): 5.5–9, 7; 2–3.5, 3; 1–2, 2; 2–2.5, 2.5. AR 0.94–1.25, 1.08. Basal antennal segment 8–10.5, 9.5 µm wide; blade 7–10, 8.5 µm long, accessory blade 3.5–6.5, 5 µm (7) long. Sensilla basiconica 2–3.5, 2.5 µm (6) long. subapical style of second segment 3–4, 3.5 µm (6) long. Premandible 37–46, 42 µm long. Mandible ( Fig. 88 I ) 62–85, 72 µm long; with 3 inner teeth, seta subdentalis 3–3.5 µm long; seta interna absent. Mentum as in Fig. 88 J , median tooth 18–27, 22 µm wide, ventromental plate 6–13, 8 µm wide in flattened mentum. Postmentum 48–59, 53 µm long. Abdomen ( Fig. 88 K ). Anterior parapods completely fused, 37–57, 40 µm long, each with 5–8, 7 longer claws. Posterior parapods 34–57, 41 µm long, each with 3 claws each 9–18, 14 µm long. Dorsal anal tubules 18––43, 26 µm long, 11–27, 18 µm (6) wide. Ventral anal tubules 25–46, 29 µm long, 14–37, 24 µm (7) wide.

Third instar larva (n = 3–4, except when otherwise stated)

Total length 1.40–1.62, 1.48 mm. Head capsule length 0.12–0.14, 0.13 mm.

Head. Length of antennal segments (in µm): 3.5–5.5; 2–2.5; 1–2; 1.5–2. AR 0.73–1.00. Basal antennal segment 7–8 µm wide, blade 5.5–7.5 µm long, accessory blade 4.5 µm (1) long; sensilla basiconica 2 µm (1) long. Subapical style of second segment 2 µm long. Premandible 32–34 µm long. Mandible 46–59, 53 µm long. Median tooth of mentum 18–27 µm wide, ventromental plate 7–11 µm wide in flattened mentum. Postmentum 34–43, 39 µm long.

Abdomen. Posterior parapods 41 µm (2) long, each with 3 claws, 10–16, 13 µm long. Anal tubules 25 µm (2) long, 14–18 µm (2) wide.

Remarks

The only differences between the Hawaiian paratypes and the other North American specimens consists of the notum being shorter in the paratypes, 55–71 µm as opposed to 75–89 µm long, and 23 setae on S VIII of the paratypes as opposed to 12–17 setae on S VIII in the other specimens. None of these differences are significant.

Ecology and distribution

All the collections of larvae were from moist banks of the Savannah River. However, other findings suggest that the species live near intermittent streams and possibly in logs. The species is known from Hawaii, South Carolina, Georgia and Ontario.

Figures

FIGURE 88. Pseudosmittia paraconjuncta (Hardy), female, immatures. A—female wing; B—dorsomesal lobe; C—ventrolateral lobe; D—apodeme lobe; E—female genitalia, ventral view; F—female genitalia, dorsal view; G—female pupa, posterior segments, lateral view; H—larval antenna; I—larval mandible; J—larval mentum; K—posterior end of larva, anal tubules separated.