Pseudosmittia forcipata (Goetghebuer)

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 : 297-301

Pseudosmittia forcipata (Goetghebuer)

( Figs.117 A–E , 118 )

Camptocladius forcipatus Goetghebuer, 1921: 87 .

Smittia (Pseudosmittia) forcipata Goetghebuer 1943:106 .

Pseudosmittia forcipata (Goetghebuer) ; Pinder 1978: 94, Cranston & Oliver 1988: 450, Saether 2006: 29 , Makarchenko & Makarchenko 2008: 219; Langton & Pinder 2007: 136; Andersen et al. 2010: 39.

Smittia triappendiculata Goetghebuer, 1931: 216 ; Saether & Ferrington 2003: 4.

Pseudosmittia antillaria Saether, 1981:29 ; Saether & Ferrington 2003: 3.

Pseudosmittia mongolzeaea Sasa et Suzuki, 1997b: 185 .

Material examined: BELGIUM: East Flanders, Destelbergen , holotype male, 31.x.1916, M. Goetghebuer ( IRSN) . Paratypes: 1 male, 1 female, same data as holotype, ( IRSN) . BELGIUM: East Flanders, Zwijn, Knockes-sur-Mer , 1 male, 9.ix.1931, M. Goetghebuer, holotype male of P. triappendiculata (IRSN) ; West Flanders, De Panne , 4 males, 6– 15.ix.1933, M. Goetghebuer (1 misidentified as P. gracilis ) ( IRSN) ; East Flanders, Hamme , 1 male, 4.vii.1938, De Wulf ( IRSN) . GERMANY: Bavaria, Obergurgl , 1 male, 5.viii.1968, F. Reiss ( ZSM) ; 2714 1 male, (GP721) ( NMS) . SWITZERLAND: Ticino, Locarno, Bolle di Magadino Piattone , seudocanneto 194.10 m, 14–20.v.1998, 1 male, L. Pollini ( ZMBN) . NORWAY: Nordland, Bodø, Bukktjernan , 16.vii.1980, A. Fjeldså ( UMSP) ; Hordaland, Vaksdal, Ekse , 1 larva, 17.vii.1989, G. Raddum ( ZMBN) . THAILAND: Mae Chaem District, Doi Inthanon , 1 male, 27.iii.– 3.iv.1990, H. Malicky ( ZSM) . CHINA: Ningxia, Mount Helan , 1 male, 31.vii.1987, X. Wang ; Ningxia, Mount Liupan , 1 male, 6.viii.1987, X. Wang ; Sechuan, Oolong , 2000 m a.s.l., 1 male, 27.vii.1987, X. Wang (all XW) . MONGOLIA: Mount Bogdrhan , 2,400 m a.s.l., holotype male of P mongolzeae , 5.viii.1995, H. Suzuki ( NMST) . SAINT VINCENT: Majorca Estate , SVT 218B, 1 male August 1972, A. D. Harrison, holotype of P. antillaria (Type no. ZMBN 33 ) ; 3 males, paratypes, same data as holotype ( ZMBN) . BRAZIL: Amazonas State, Rio Maranja, outlet from mountains ( upper Rio Negro ), A504, drift, 1 male, 29.i.1963, E. J. Fittkau ; Para State, Rio Para de Oeste, Oberland, Mission Tiriyos , 1 male 22–23.vii.1962, A356–1, drift, E. J. Fittkau ( ZSM) ; Rio de Janeiro State, Itatiaia, Penedo-Gramado entomo do Lago da Pousada do Lago , 3 males, 16.vi.1963, Silva-da-Silva & Oliveira ( ZMBN) . PERU: Mouth of Rio Azul in Rio Tullumayo, 1 male, 21.v.1963, E. J. Fittkau ( ZSM) . COLUMBIA: Antiochia, near Medellin , 1700 m a. s. l., 1 male, 28.iv.1983, M. Wolf ( ZSM) . CANADA: British Columbia, Manitoba, Nova Scotia . USA: California, Colorado, Florida, Kansas, Kentucky, Louisiana, New Mexico, North Carolina, South Carolina, South Dakota, Tennessee, Washington, Wisconsin, Wyoming, 196 males, 8 females, 4 pupae, including uncertain males, 18 larvae ( BAC, CNC, CVC, FLAM, JES, UMSP, SKV, VCR, ZMBN) .

Diagnostic characters: The male imago can be separated from other species with superior and median volsellae by the shape of the accessory lobe of the inferior volsella, and AR of 0.74–1.48 (0.54 if P. triplex is included), an anal point length of 11–48 µm, and a clearly sinuate Cu 1. The female can be distinguished from other females with tergite IX divided by broad caudal notch and slight or no caudal projection of gonocoxites by lacking a strong apical seta on the antenna. The pupa has uneven shagreen spinules on tergal conjunctives III/IV, VI/VII and sternal conjunctives IV/ V–VII/VIII, no setae on anal segment, no nose on wing sheath, no stronger spinules or spines on anal segment, female genital sac without spinules, but tentatively associated male exuviae with basiventral but not apical spinules. The larva has a mandible with 3 inner teeth, posterior parapods with 5 claws and antennal blade 2–3 times as long as width of basal antennal segment and cannot be distinguished from P. trilobata .

Male imago (n = 10–14, except when otherwise stated)

Total length 1.17–2.10, 1.71 mm. Wing length 0.77–1.31, 1.01 mm (80). Total length/wing length 1.53–1.86, 1.66. Wing length/length of profemur 3.09–3.43, 3.27. Coloration fully brown, including haltere knob.

Head. AR 0.70–1.48, 1.02 (73). Terminal flagellomere 215–441, 308 µm (72) long. Temporal setae 4–7, 6, consisting of 2–3, 3 inner verticals, 2–3, 3 outer verticals and 0–1, 0 postorbitals. Clypeus with 6–12, 10 setae. Cibarial pump, tentorium and stipes as in Fig. 117 A . Tentorium 91–130, 109 µm long, 18–33, 23 µm wide. Stipes 82–126, 106 µm long, 18–34, 28 µm wide. Palpomere lengths (in µm): 21–30, 24; 25–43, 35; 49–94, 68; 57–103, 76; 78–142, 101. Third palpomere ( Fig. 117 B ) with 2–3, 2 lanceolate sensilla clavata.

Thorax ( Fig. 117 C ). Median antepronotal lobes moderately reduced, antepronotum with 1–2, 1 lateral setae. Dorsocentrals 7–12, 9; acrostichals 2; prealars 3–4, 4. Scutellum with 4–8, 6 setae.

Wing ( Fig. 117 D ). VR 1 1.43–1.67, 1.55. Anal lobe present but not projecting, postcubital fork occasionally indicated with VR 2 about 1.30. Costal extension 7–23, 15 µm long. R 4+5 ending distinctly proximal to apex of M 3+4; Cu 1 sinuate. Brachiolum with 1 seta, other veins bare.

Legs. Spur of front tibia 27–47, 39 µm long, spurs of middle tibia 18–32, 27 µm and 14–30, 20 µm long, of hind tibia 32–46, 39 µm and 16–25, 19 µm long. Width at apex of front tibia 18–27, 23 µm, of middle tibia 19–27, 23 µm, of hind tibia 25–40, 32 µm. Comb of 10–15, 12 setae, shortest setae 14–23, 20 µm long, longest setae 25–39, 31 µm long. Lengths and proportions of legs as in Table 77.

Hypopygium ( Fig. 117 E ). Anal point 11–48, 27 µm (86) long; tergite IX with 8–16, 11 setae; laterosternite IX with 3–5, 4 setae. Phallapodeme 71–103, 83 µm long, apodeme lobe with 7–11, 9 wrinkles; transverse sternapodeme 34–64, 47 µm long, usually without trace of oral projections. Virga triangular, 16–32, 23 µm long. Gonocoxite 119– 160, 139 µm long; superior volsella 18–39, 29 µm (86) long, median volsella 18–48, 27 µm (86) long; inferior volsella 14–30, 23 µm (87) long, 13–32, 22 µm (87) wide including more or less rounded, wrinkled or serrated accessory lobe with numerous orally curved microtrichia. Gonostylus 48–66, 56 µm long, tapering to apex, covered along mesal margin with long anteriorly directed microtrichia; megaseta 9–11, 10 µm long. HR 2.31–2.71, 2.46, HV 2.21–3.55, 2.99.

Female imago (n = 9–10, except when otherwise stated)

Total length 1.26–1.67, 1.46 mm. Wing length 0.68–0.95, 0.83 mm. Total length/wing length 1.59–1.91, 1.67. Wing length/length of profemur 3.02–3.88, 3.35. Coloration as in male or distinctly more pale.

Head. AR 0.41–0.51, 0.45, no strong apical seta ( Fig.118 B ). Flagellomeres 2–4 fusiform. Lengths (in µm) of flagellomeres: 46–59, 53; 32–42, 37; 34–46, 39; 32–45, 38; 41–82, 72. Temporal setae 4–6, 5, including 2–3, 3 inner verticals, and 2–3, 2 outer verticals. Clypeus with 6–11, 8 setae. Tentorium 78–103, 90 µm long, 9–14, 10 µm wide. Stipes 62–89, 79 µm (8) long, 18–25, 21 µm wide. Palpomere lengths (in µm): 14–25, 20; 18–34, 26; 41–59, 54; 48– 71, 62; 69–98, 82. Third palpomere with 3–6, 4 (7) lanceolate sensilla clavata, fourth palpomere with 0–1, 1 (6) sensillum clavatum. Coronal suture 0–14, 3 µm long.

Thorax. Median antepronotal lobes moderately produced, lateral setae of antepronotum 1–2, 1. Dorsocentrals 8– 13, 9; acrostichals 2; prealars 3–4, 3; no supraalar seta. Scutellum with 4–6, 5 setae.

Wing ( Fig. 118 A ). VR 1.31–1.66, 1.52. Anal lobe reduced. Costal extension 14–48, 40 µm long. R 4+5 ending proximal to apex of M 3+4; Cu 1 curved. Brachiolum with 1 seta; costa from R to apex of R 4+5 with 8–25, 15 non-marginal setae; costal extension with 1–6, 4 non-marginal setae; R with 4–9, 7 setae; R 1 with 1–5, 3; R 4+5 with 4–13, 9 setae; other veins bare.

Legs. Spur of front tibia 23–27, 24 µm (7) long, spurs of middle tibia 14–22, 19 µm (8) and 13–17, 15 µm (8) long, of hind tibia 30–39, 34 µm (8) and 14–21, 17 µm long. Width at apex of front tibia 18–25, 22 µm, of middle tibia 21–27, 24 µm, of hind tibia 27–37, 32 µm. Comb of 10–14, 11 setae; shortest setae 16–21, 18 µm long, longest setae 23–34, 29 µm. Lengths and proportions of legs as in Table 78.

Abdomen. Tergite I bare, T II–VIII each with 6–14, 10 setae. Sternite I bare; S II with 0–2, 0 setae; S III with 1– 5, 2; S IV with 2–4, 3; S V with 2–6, 4; S VI with 4–6, 5; S VII with 4–7, 5; S VII with 18–28, 22 setae.

Genitalia ( Fig. 118 C–G ). Gonocoxite with 2–4, 3 strong and 2–6, 3 weak setae, mostly on caudolateral corner or slight projection. Tergite IX divided by wide notch ( Fig. 119 F ), with altogether 6–11, 9 setae. Cercus 39–71, 49 µm long. Apodeme against gonocoxite 62–82, 67 µm long. Seminal capsule pale, ovoid; 43–69, 56 µm long, 34–51, 44 µm wide (2 specimens apparently without seminal capsules), with 8–11, 10 µm (8) long microtrichia. Spermathecal ducts without bulbs before common opening. Notum 59–80, 73 µm long. Coxosternapodeme with median caudal tooth.

Pupa (n = 3 including tentatively associated male exuviae)

Total length not measurable in female, 2.66 mm (1) long in male. Exuviae tinged with brownish yellow on cephalothorax, some with grayish brown on abdomen.

Cephalothorax. Frontal setae about 60 µm (1) long. Longer setae on cephalothorax about 40–60 µm (1) long, shorter about 20 µm (1) long. Distance between Dc 1 and Dc 2 55–64 µm (2), between Dc 2 and Dc 3 9–17 µm (2) and between Dc 3 and Dc 4 4–14 µm (2).

Abdomen. Tergite I bare or with weak caudolateral spinules; T II–IX with coarse shagreen covering most of tergite, with stronger anterior and posterior spinules. Sternites I–II or III bare; S III or S IV with a few median spinules; S V with few anterior, lateral and caudomedian spinules; S VI–VIII with spinules over most of segment except in front of posterior groups; S IX with a few anteromedian spinules. Genital sac of female without spinules, of tentatively associated male with basiventral but not apical or dorsal spinules. Tergal conjunctive III/IV with 10–12 (2 females) or 2 (1 male) spinules; IV/V with 11–18 (2 females) or 75 (1 male); V/VI with 20–32 (3 females) or 86 (1 male); VI/VII with 16–28, (2 females) or 55 (1 male) spinules. Sternal conjunctive IV/V with 2 (1 female) or 59 (1 male), V/VI with 20–28 (2 females) or 104 (1 male); VI/VII with 36–38 (2 females) or 75 (1 male); and VII/VIII with 22 (1 female) or 72 (1 male) spinules. Segment IX without setae.

Fourth instar larva (n = 13–18, except when otherwise stated)

Total length 1.71–3.42, 2.45 mm. Head capsule length 0.20–0.24, 0.22 mm.

Head. Antenna as in Fig. 118 H . Length of antennal segments (in µm): 7–10, 8.5; 2–3.5, 3; 2–3.5, 2; 2–2.5, 2.5. AR 1.00–1.38, 1.13. Basal antennal segment 11–16, 14 µm wide; blade 27–38, 32 µm (19) long; accessory blade 3.5– 7, 5 µm long. Sensilla basiconica 2–3.5, 3 µm long. Subapical style of second segment 3.5–5.5, 4.5 µm long. Premandible ( Fig. 118 I ) 46–55, 50 µm long. Mandible ( Fig. 118 J ) 78–99, 83 µm long; with 3 inner teeth; seta subdentalis 2.5–5.5, 4 µm (11) long; seta interna absent. Mentum as in Fig. 118 K , median tooth 21–26, 25 µm wide, ventromental plate 7–13, 10 µm wide in flattened mentum. Postmentum 62–80, 71 µm long.

Abdomen ( Fig. 118 L ) Anterior parapods 34–57, 43 µm (8) long, each with about 20 longer claws. Posterior parapods 30–46, 42 µm (7) long, each with 5 claws, 5.5–7, 6.5 µm long. Dorsal anal tubules 16–39, 29 µm (6) long, 14–37, 24 (5) µm wide. Ventral anal tubules 34–57, 43 µm (6) long, 25–69, 39 µm (5) wide.

Remarks

The very large variation in size, male antennal ratio and shape of accessory lobe of the inferior volsella suggests that more than one species may be involved. However, some of the smallest specimens we examined were found together with some of the largest and at present there does not seem to be any way of subdividing the species along geographical or seasonal lines. In fact, some of the closely related species described below may also be varieties of P. forcipata . Pseudosmittia triplex , for example, has previously been regarded as a synonym of P. forcipata . A specimen from Marion Lake, British Columbia, Canada, lacks an anal point, but is tentatively assigned to the species since other details fits the description except that there appears to be at most five wrinkles on the phallapodeme.

Pseudosmittia forcipata clearly is facultative parthenogenetic. In the population from Georgia where our reared material originates there are only females. A large variation is to be expected with facultative parthenogenetic species. The tentatively associated male is from the Savannah River in Georgia and we do not have any males from exactly the same date and localities, but several from nearby localities along the Savannah River. No other males of other species of the genus were collected from the same area as the pupa, therefore we conclude that it belongs to P. forcipata .

Ecology and distribution

The species is widely distributed all over the Holarctic and Neotropical regions. In addition to the provinces of Canada and states of the USA mentioned in the material studied section, Cranston and Oliver (1988:450) mention the species from New Brunswick and Vermont. The record from Thailand is from the highest mountain in the country near Chiang Mai in the north, but still within the Oriental region . Reared larvae from Georgia were from moist or saturated soils over lateral lines of septic system in an urban lawn. It is likely that larvae of this species typically inhabits similar types of moist or saturated organically rich substrate .

Figures

FIGURE 117. Pseudosmittia spp., males. A–E, P. forcipata (Goetghebuer); A—cibarial pump, tentorium and stipes; B—palp; C—thorax; D—wing; E—hypopygium, left dorsal aspect, right ventral aspect; F—P. triplex Strenzke, male. (E from Andersen et al. 2010.)

FIGURE 118. Pseudosmittia forcipata (Goetghebuer), female, larva. A—wing; B–antenna; C—dorsomesal lobe; D—ventrolateral lobe; E—apodeme lobe; F—female genitalia, dorsal view; G—female genitalia, ventral view; H—larval antenna; I—premandible; J— mandible: K—mentum; L—abdomen, caudal apex.

FIGURE 119. The most parsimonious area cladograms summarizing relationships among areas inhabited by different genera and groups resulting from a BPA of the area cladogram in Fig. 6B and a corresponding data matrixes. A—Allocladius, strict consensus of 4 trees; B—Hydrosmittia, the single tree obtained; C—brevicornis group, strict consensus of 2 trees; D—Pseudosmittia, strict consensus of the 4 trees obtained; E—the single tree obtained for the paraphyletic topei group; F—the single tree obtained for the xanthostola group.