Nemotelus notatus Zetterstedt (Stagno di s'Ena Arrubia 1842

Nemotelus notatus Zetterstedt, 1842

(Figs 25–60)

Nemotelus notatus Zetterstedt, 1842: 148.

Nemotelus brachystomus Loew, 1846: 443 syn. nov.

Nemotelus leuchorynchus Costa, 1884: 61 syn. nov.

Published records. Sardinia (Rozkošný 2004). Cagliari prov.: Cagliari (Costa 1884, as N. leucorhynchus); Santa Gilla, Saline di Santa Gilla (Mason 2005, as N. brachystomus). Carbonia-Iglesias prov.: Isola di San Pietro, La Caletta (Mason 2005). Sassari prov.: Stintino (Mason 1988).

Material examined. Carbonia-Iglesias prov.: Sant’Anna Arresi, Stagno di Punta Pino, N 38°58’24.0” E 8°36’34.4”, 22.VI.2007, F. Mason, D. Birtele & F. Mazzocchi, 1 ♀, sweep net, on Salicornia sp. (FMV); Sant’Antioco, Stagno di Santa Caterina, N 39°04’56.1” E 8°29’21.9”, 22.VI.2007, F. Mason, D. Birtele & F. Mazzocchi leg., 10 ♂, 7 ♀♀, sweep net, on Salicornia sp. (FMV). Oristano prov.: S. Giovanni di Sinis, Stagno di Mistras, N 39°53’15.3” E 8°26’48.8”, 23.VI.2007, F. Mason, D. Birtele & F. Mazzocchi 1 ♂, sweep net, on Salicornia sp. (FMV); Cabras, Stagno di Cabras, N 39°55’35.4” E 8°27’53.8”, 23.VI.2007, F. Mason, D. Birtele & F. Mazzocchi leg., 1 ♂, 1 ♀, sweep net, on Salicornia sp. (CNBFVR); Arborea, Stagno di Santa Giusta, N 39°52’05.9” E 8°35’22.3”, 25.V.2006, 10 ♂ 7 ♀♀, M. Bardiani, D. Birtele, P. Cornacchia & D. Whitmore leg., sweep net, on Salicornia sp., (FMV); same data but N 39°51’15.7” E 8°35’55.5”, 23.VI.2007, F. Mason, D. Birtele & F. Mazzocchi leg., 10 ♀♀ (FMV); San Vero Millis, Capo Mannu, N 40°02’16.1” E 8°22’30.2”, 22.VI.2002, B. Merz & M. Eggenberger leg., 1 ♂, sweep net (FMV); San Vero Milis, Stagno di Putzu Idu, N 38°58’24.0” E 8°36’34.4”, 23.VI.2007, F. Mason, D. Birtele & F. Mazzocchi leg. 3 ♂, 4 ♀♀, sweep net, on Salicornia sp. (FMV); Arborea, Stagno di s’Ena Arrubia, N 39°49’49.5” E 8°33’37.6”, 23.VI.2007, F. Mason, D. Birtele & F. Mazzocchi leg., 38 ♂, 37 ♀♀, on Juncus sp. sweep net (FMV); Sassari prov.: Stintino, Saline [= Saltworks] Tonnara, N 40°54’23.2” E 8°13’59.8”, 24.VI.2007, F. Mason, D. Birtele & F. Mazzocchi leg., 5 ♀♀, sweep net, on Salicornia sp. (FMV); Olbia, Saline [= Saltworks] di Porto Palo, N 40°54’16.5” E 9°34’23.2”, 24.VI.2007, F. Mason, D. Birtele & F. Mazzocchi leg., 1 ♀, sweep net, on Salicornia sp. (FMV); Stintino, 30.V.1950, A. Servadei leg., 1 ♂ (FMV); Olbia-Tempio prov.: San Teodoro, Stagno di San Teodoro, N 40°47’04.4” E 9°39’37.8”, puparium collected on 24.VI.2007, emerged in laboratory on 2.VII.2007, F. Mason, D. Birtele & F. Mazzocchi leg., salt marsh, 1 ♂ (FMV).

Other material examined. France, Bouches du Rhône, plage de Faraman, 10.VII.1986, 1♂ (FMV); Italy, Venetia, Venice prov., Alberoni, Giordani-Soika leg., 16.VI.1970, J. I. Maldes leg., net, 1 ♂ (FMV); Italy, Ferrara prov., Comacchio [salt marsh], 15.V.2002, F. Mason leg., 1♂ (FMV); Italy, Latium, Latina prov., Parco Nazionale del Circeo, Sabaudia, Pantani dell’Inferno [salt marsh], N 41.20 E 12.5, B. Merz, P. Cerretti & G. Nardi leg., 2.IX.2004, net, 1 ♂, 19 ♀♀ (FMV); Italy, Apulia, Foggia prov., Lesina Lake, saltmarsh, on Salicornia sp., 25.VII.1990, F. Mason leg., 1♂ (FMV); Italy, Sicily, Trapani prov., Egadi Islands, Favignana Island, 2.V.1991, net, Osella leg., 1 ♂ (FMV).

Remarks. The lectotype of N. notatus, from Copenhagen (Denmark), and that of N. brachystomus, from Dalmatia (Croatia), were designated and compared by Rozkošný (1977), who stated that the terminalia of both sexes of both species were identical. Nevertheless, he believed that the facial projection is usually shorter and the underside of the abdomen mostly lighter in N. brachystomus than in N. notatus. Rozkošný (1983) considered both species as valid, although he suggested they may be conspecific. During the last two decades we had the opportunity to examine a large number of specimens from the Mediterranean area (cf. Rozkošný 1977, 1983; Mason 1988; Hauser 2008), comparing them with populations from northern and western Europe. Also specimens from Italy, including Sardinia, provided further evidence of the chromatic pattern variability of this species, without any relation to their geographic distribution (cf. Mason 1988). In particular, the species varies in the colour of the antennae, the length of the facial projection, and in the abdominal pattern of both sexes (although the extreme colour forms are less frequent in females). We suppose that the occurrence of individual forms may depend on the degree of salinity and temperature of water in which the larvae and puparia developed. Extremely pale specimens (Figs 42, 47–48) are known from Egypt, but this is also well known in some other soldier flies with similar large areas of distribution in the Western Palaearctic, e.g., Stratiomys longicornis (Scopoli, 1763). We thus conclude that all variants with identical terminalia from Europe, North Africa and the Near East belong to a single species.

One of the adults was reared from a puparium in the lab, and the larvae can thus be compared with the diagnostic characters published for the larva of N. notatus (cf. Lenz 1923; Brindle 1964; Rozkošný 1973). The larva of N. notatus can be distinguished from the similar larva of N. uliginosus (Linnaeus, 1767) by the pattern of the abdominal segments, the shape and the chaetotaxy of the anal segment (cf. Stubbs & Drake 2001: 57).

The holotype of N. leuchorynchus, originally housed in the “Museo Zoologico dell’Università di Napoli Federico II”, is very probably lost. The original description, with the smooth dorsal yellow spot on the facial projection, the brown antennae darkened along the dorsal surface and tip and the black median dorsal part of the fifth abdominal tergite with the ivory-white posterior margins probably refers to dark males of N. notatus. This conclusion is also supported by the fact that this species was very abundant in the Stagno di Cagliari on “salsola” [= Salicornia sp.] (cf. Costa 1884), i.e. in the locality near Cagliari where many specimens of N. notatus were recently collected.

The biometric measurements refer to the population collected on the same day at Stagno di s’Ena Arrubia. Males (n = 10): body = 5.1–7.9 mm, wing = 3.3–6.2, head index = 1.1–1.2; females (n = 11): body = 4.5–6.7, wing = 2.9–5.2, head index = 1.1–1.4. Head indices of males originating from different parts of Italy are summarized in Tab. 2. According to Rozkošný (1983), the head index of all the populations examined by him ranges between 1.15 and 1.28 in males and between 1.25 and 1.50 in females.

Distribution. Mainly a coastal element but occurring also around inland salt pools and marshes. Well known from southern Scandinavia and Finland, western Europe to southern-most Spain, the Balearic Islands, southern France, Italy (including Sardinia) and the coasts of the Balkan Peninsula including the Black Sea (Croatia, Albania, Romania, Bulgaria, Greece, Ukraine); also occurs in Egypt, Cyprus, the Near East and North Africa. Inland localities are known in Austria, Hungary, Romania and the southern, central and eastern parts of Russia (Rozkošný 2004).