Palpomyia schmidti (Goetghebuer, 1934),

Szadziewski, Ryszard, Golovatyuk, Larisa V., Sontag, Elżbieta, Urbanek, Aleksandra & Zinchenko, Tatiana D., 2016, All stages of the Palaearctic predaceous midge Palpomyia schmidti Goetghebuer, 1934 (Diptera: Ceratopogonidae), Zootaxa 4137 (1), pp. 85-94: 86-92

publication ID

http://doi.org/10.11646/zootaxa.4137.1.6

publication LSID

lsid:zoobank.org:pub:BE0AA599-B51C-4CE7-8B84-BFCB28F0665F

persistent identifier

http://treatment.plazi.org/id/03D887CD-127D-FFFE-FF06-07120C40FD4D

treatment provided by

Plazi

scientific name

Palpomyia schmidti (Goetghebuer, 1934)
status

 

Palpomyia schmidti (Goetghebuer, 1934) 

Palpomyia schmidti Goetghebuer, 1934 a: 36  ( Iraq, female) (5 March 1934); Szadziewski et al. 2009: 195 ( Iraq, female redescribed, male diagnosed, figs, syn. P. miki  ).

Palpomyia miki Goetghebuer, 1934 b: 91  ( Hungary, female, fig. total habitus) (20 April 1934); Remm 1976: 175 ( Russia, female, male, figs); Delécolle et al. 1997: 342 ( Spain, female, figs).

Diagnosis. The only species in the genus with a triangular gonocoxite and totally separated parameres in the male genitalia, femora and tibiae armed with dark spine-like bristles. Females can be separated from other Palaearctic congeners in that they have simple claws, all femora armed with ventral spines, mid and hind tibiae with dorsal spine-like bristles, basitarsus of midleg with some median spines. Larvae: head relatively broad; collar of the head capsule with a triangular ventral expansion; a long epicranial suture (ES), reaching the level of seta q; a dorsal paired comb of the epipharynx with long, slender teeth. Pupae: dorsal apotome with 1 pair of setae and 1 pair of sensory pits (sensilla campaniformia); numerous spiracles arranged in a horseshoe shape, occupying the distal half of the respiratory horn.

Description. Female. Head yellowish. Eyes broadly separate, vertex with strong setae ( Fig. 2View FIGURE 2 A). Antennal flagellum 0.90 mm long, AR 0.84–0.86. Proximal flagellomeres subcylindrical, distal cylindrical ( Fig. 2View FIGURE 2 B). Palpus 5 -segmented, third palpal segment stout, 0.11 mm long. Mandible with 7 stout teeth ( Fig. 2View FIGURE 2 A). Scutum yellowish with brown longitudinal stripes, scutellum yellow, postscutellum dark brown ( Fig. 2View FIGURE 2 C). Scutum without anterior tubercle, with numerous simple setae. Scutellum bearing 9–10 bristles and numerous small setae. Paratergite broad, bare. Anterior anepisternum with a group of 7–8 setae. Katepisternum dark and bare. Wing without pattern ( Fig. 2View FIGURE 2 D), length 2.10–2.90 mm, CR 0.71–0.78. Second radial cell about twice as long as first one. Base of vein M 2 proximal to vein M 1. Legs yellow with darker coxae and distal tarsomeres. Lateral surface of coxae with some setae. All femora armed with ventral spines ( Fig. 2View FIGURE 2 C). Fore femur enlarged with 6–18 ventral spines, mid femur slender with 1–4 spines and hind femur with 1–3 ventral spines. All tibiae armed with strong dark dorsal bristlelike spines. Fore tibia with 1 anterior spine, mid tibia with 4–10 spines and hind tibia with 12–16 dark spines. Tibial comb with 6–7 pale spines. First tarsal segment of foreleg armed with 2 apical spines, that of midleg with 2 basal, 5–6 median and 2 apical spines, hindleg with 5 dark spines, palisade setae in one row. Fourth tarsomere subcylindrical. Tarsal ratio of foreleg TR (I) 1.6–1.8, midleg TR (II) 1.9–2.2, hindleg TR (III) 1.8 –2.0. Claws almost equal, simple, without internal basal tooth. Abdomen yellow with brownish triangles on tergites. Two pairs of apodemes of eversible sacs present. Seminal capsules ovoid, unequal, with distinct necks, length 0.08–0.11 mm, and 0.06–0.08 mm ( Fig. 2View FIGURE 2 E).

Male. Similar to female with the usual sexual differences. Eyes broadly separate. Flagellum 0.765 mm long, with greatly reduced plume, all flagellomeres cylindrical, terminal three slightly elongate ( Fig. 3View FIGURE 3 A). Proportions of flagellomeres as follows: 40 - 15 - 15 - 15-16 - 15 - 15 - 14-16 - 16-20 - 25-35. Third palpal segment stout, 0.037-0.045 mm long, with some sensilla capitata on surface.

Wing length 1.60–1.75 mm, CR 0.73–0.75. Tibial comb with 7–8 spines, hind tibial spur short. Tarsal ratio TR (I) 1.9, TR (II) 2.5–2.6, TR (III) 1.8 –2.0.

Genitalia as in Fig. 3View FIGURE 3. Sternite 9 with broad caudomedian excavation. Tergite 9 elongate, with broad cerci. Gonocoxite stout, as long as broad, with long triangular internal extension Fig. 3View FIGURE 3 C). Gonostylus stout, evenly bent, with pointed dark apical portion Fig. 3View FIGURE 3 D). Aedeagus stout, scutiform and covered with short spiculae; basal arch high; apex with evenly rounded cap ( Fig. 3View FIGURE 3 E). Parameres separate, apex distinctly expanded, bulbous ( Fig. 3View FIGURE 3 F).

Pupa. Body pale brown ( Fig. 4View FIGURE 4). Length: female 4.3–6.6 mm; male 4.9–5.5 mm. Respiratory horn ( Fig. 5View FIGURE 5 C) slender, about 3.8–4.1 times longer than broad, surface bare, distal half with about 40 spiracles in one horseshoelike row, length 0.40–0.46 mm in male, 0.460– 0.510 mm in female. Dorsal apotome (operculum) ( Fig. 5View FIGURE 5 B) 1.0– 1.3 times as long as greatest width, covered with small tubercles, posterior margin pointed; anterolateral tubercle bearing single long seta and single sensory pit (campaniform sensillum). Antennae short, ventrally wings separated by legs ( Fig. 5View FIGURE 5 A). Caudomedian expansion of mesothorax indistinct, evenly rounded ( Fig. 4View FIGURE 4 B). Metathorax slender, distinctly emarginated, with single pair of sensilla campaniformia (M- 3 -T) ( Fig. 5View FIGURE 5 D). Abdominal segments with scattered small spinules. Tergites 1–7 with medial area displaying 1 longitudinal stripe and 2 darker spots ( Fig. 4View FIGURE 4 B). First abdominal tergite with 3 groups of setae on lateral surface ( Fig. 5View FIGURE 5 D); anterodorsal group including 2 setae and 1 sensory pit (campaniform sensillum), posterodorsal group with 2 setae and 1 sensory pit; lateral group composed of 3 setae. Dorsal surface of fourth abdominal segment with setae and sensory pits as in Fig. 5View FIGURE 5 E. Dorsal seta D- 2 on rounded pale spot. Ventral surface only with two groups of 3 small setae (V-5,6,7). Abdominal segment 9 without setae, but with 2 dorsal sensilla campaniformia (D-5, 6) on apicolateral processus. Apicolateral processes of terminal abdominal segment 9 highly variable, long or short, covered with spinules or bare, slightly to greatly divergent ( Figs. 5View FIGURE 5 F,G). In females apicolateral processes ( Fig. 5View FIGURE 5 F) more divergent than in males ( Fig. 5View FIGURE 5 G).

Larva. IV instar ( Figs. 6View FIGURE 6, 7View FIGURE 7). Body slender ( Fig. 6View FIGURE 6 A), total length to 11–12 mm. Head capsule pale brown, slightly conical, 1.925 as long as broad (HR), subgenal ratio (SGR) 1.951. Collar narrow, brownish; on ventral surface with distinct triangular extension ( Fig. 7View FIGURE 7). Epicranial suture moderately long, reaching level of seta q ( Fig. 7View FIGURE 7 A, C). Sensory pits (sensilla campaniformia) r, k, z, j indistinct. Setae s, u, o, x forked. Labrum slightly elongate, almost square with sensory organs typical of the subfamily; messors slightly sclerotized, hook-shaped. Mandible slender, hook-like, with double hook at midlength; fossa mandibularis distinct ( Fig. 6View FIGURE 6 G, H). Labium triangular with distinctly pointed apex ( Fig. 6View FIGURE 6 E). Hypostoma broad, slightly arched, smooth ( Fig. 6View FIGURE 6 E). Hypopharynx elongate, slightly sclerotized, hypopharyngeal fringe indistinct ( Fig. 6View FIGURE 6 E, F). Epipharynx with single, dorsal comb armed with 24–26 teeth on its posterior margin ( Fig. 6View FIGURE 6 H), 0.068–0.075 mm wide.

Neck or cervix distinct, about 7 times shorter than prothorax ( Fig. 6View FIGURE 6 B). Body segments moderately elongate, second thoracic segments 1.0– 1.4 times longer than broad, abdominal segments about 1.5 times longer than broad. Anal segment slender, 3.3 times longer than broad; apex with group of 2 short outer and 2 long inner setae on dorsal and ventral surfaces ( Fig. 6View FIGURE 6 C, D); 2 dorsal and 2 ventral short caudal setae, in addition 2 lateral setae at level of shorter dorsal/ventral setae and 2 before mid-length of segment present ( Fig. 6View FIGURE 6 C).

Distribution and ecology. The species is halobiontic and represents the meridional faunal element in the Palaearctic Region ( Szadziewski 1985) or the Saharo-Arabian element ( Alwin-Kownacka et al. 2016). It was usually collected on rivers in steppes and deserts ( Remm 1976). It has been reported from Iraq ( Goetghebuer 1934 a), Hungary ( Goetghebuer, 1934 b), Spain ( Delécolle et al. 1997), Slovakia ( Tothova & Knoz 2006), Ukraine (Crimea), Russia (Rostov, southern Siberia), Azerbaijan, Tadjikistan, Kazakhstan, Iran, southern Siberia and Mongolia ( Remm 1976, 1988). We are unable to confirm Remm’s (1976, 1988) reports of the species from northern China.

Larvae of P. schmidti  were observed in black and grey sandy mud, often with plant debris in the Rivers Chernavka, Solyanka, Lantsug, Khara and Bolshaya Samoroda, which flow into Lake Elton ( Figs 1View FIGURE 1 B, C). They were also observed among dense filamentous algae and Enteromorpha intestinalis  . Larvae were collected at depths of 0.03–0.8 m, where the water was flowing at 0.01–0.4 m s - 1. They live in riverine waters with salinities of 5.8– 31.7 g l - 1, dissolved oxygen concentrations of 2.3 –35.0 mg l - 1 and pH levels of 6.5–9.4. These larvae were also found at the bottom of Lake Elton, where the salinity was 112.5 g l - 1. In the Chernavka, larvae of P. schmidti  occurred together with Cricotopus (Cricotopus) salinophilus Zinchenko, Makarchenko & Makarchenko, 2009  and Chironomus salinarius Kieffer, 1915  .

Under laboratory conditions, mature larvae pupated within 1–2 days. The pupal stage lasted 3 days. In the aquarium pupae floated on the water surface. Among the emerging adults, females were distinctly predominant over males, with a percentage ratio of 85: 15 in favour of the former. Larval and pupal mortality in the laboratory was less than 5 %, a very low figure.

The abundance of 48 0 0 0 ind./m - 2 recorded in the Chernavka (28 May 2015) is probably a maximum value for populations of larvae of this species in saline rivers. The average abundance and biomass were much higher in the highly saline Chernavka and Solyanka (17.17–31.7 g l - 1) than in the less saline Khara, Lantsug and B. Samoroda (3.97–21.6 g l - 1). The theoretical ecological salinity optimum for the halobiontic larvae of P. schmidti  is 31.7 g l - 1, with the tolerance interval varying from 20.76 to 33.14 g l - 1 (unpublished data).

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Diptera

Family

Ceratopogonidae

Genus

Palpomyia

Loc

Palpomyia schmidti (Goetghebuer, 1934)

Szadziewski, Ryszard, Golovatyuk, Larisa V., Sontag, Elżbieta, Urbanek, Aleksandra & Zinchenko, Tatiana D. 2016
2016
Loc

Palpomyia schmidti

Szadziewski 2009: 195
Goetghebuer 1934: 36
1934
Loc

Palpomyia miki

Delecolle 1997: 342
Remm 1976: 175
Goetghebuer 1934: 91
1934