Myrmeleon formicarius Linnaeus, 1767

Badano, Davide & Pantaleoni, Roberto Antonio, 2014, The larvae of European Myrmeleontidae (Neuroptera), Zootaxa 3762 (1), pp. 1-71 : 52-54

Myrmeleon formicarius Linnaeus, 1767

( Figs. 5A , 6A , 26 )

Linnaeus (1745, 1758) attributed to this species some larvae that he observed in Öland ( Sweden),nevertheless the larva of this antlion was described for the first time more than a century later by Brauer (1853) as M. formicalynx (see also under E. nostras ). The larva of M. formicarius is one of the best known in the family and it was treated in numerous studies ( Hagen 1873; Redtenbacher 1883, 1884; Doflein 1916; Eglin 1940; Friheden 1973; Steffan 1975; Matsura 1987; Eisenbeis & Wichard 1987; Gepp & Hölzel 1989; Gepp 2010; Krivokhatsky 2011).

Examined specimens. Portugal. Parque Nacional da Penada , VII.2011 (B. Michel), 2 L3 . Italy. Val d’Aosta, Aymavilles (Aosta), Pont d’Ael , under rock overhang, VIII.2012 (D. Badano), 4 L3. Piedmont, Torino (Torino), VII.2010 (A. Alma), 4 L3. Tuscany, Follonica (Grosseto), VII.2010 (M. Bastianini), 2 L3. Tuscany, Montieri (Grosseto), VII.2010 (M. Bastianini), 2 L3. Tuscany, Casale Marittimo (Pisa), VII.2010 (M. Bastianini), 4 L3. Lazio, Roma (Roma), Prataglia di Cervara , VI.2010 (M. Gigli), 2 L3. Sicily, Mt. Etna , VII.2010 (F. Camino), 1 L3 .

Romania. Dobruja , Badabag, VIII.2010 (C. Manci), 1 L3 .

Description of 3 rd instar larva. Size (based on 22 specimens): BL 9.11 mm; HL 2.28 mm (2.11–2.55), HW 2.04 mm (1.80–2.42), ML 2.41 mm (2.14–2.70), HW/HL 0.89, ML/HL 1.06. General colouring dark brown with a dark pattern, ventral side pale with dark spots; dorsal side of the head capsule with large paired markings, lateral side of the head with large dark markings, ventral side mottled with dark brown with a pair of large spots ( Figs. 5A , 26c ), mandibles pale brown; legs pale, metathoracic pair of legs with dark spots on the coxae and femora ( Fig. 26d ); setae of the body black. Head slightly longer than wide; mandibles relatively robust, as long as the head capsule ( Fig. 26a ); interdental mandibular setae: (+6)(2–3)(2–3)(1); dorsal side of the mandible covered by sparse, short setae, ventral side with a thick covering of short setae external to the maxilla, reaching the median tooth and very few setae internal to the maxilla ( Figs. 5A , 26b ). IX abdominal sternite with an anterior row of digging setae composed by 4 setae divided in 2 groups and with two sessile rastra each bearing 4 digging setae ( Figs. 6A , 26e ).

Bio-ecology. M. formicarius is one of the commonest European species despite in southern Europe it is limited to mountainous habitats or to suitable fresh lowland biotopes, avoiding warm and arid sites. This species prefers habitats characterized by the presence of arboreal vegetation and of loose dry substratum. The larvae build their pits both in exposed and sheltered conditions such as under tuft of plants, rock overhangs or in proximity of small escarpments.

Distribution. Widespread Palaearctic species.

Remarks. The larva of M. formicarius is the only species in central and northern Europe with spotted metathoracic legs. The 3 rd instar larva is also recognizable due to the large dimensions, being the largest European member of the tribe.

Figures

FIGURE 5. Head of 3rd instar larvae of Myrmeleontini, ventral view; A, Myrmeleon formicarius; B, Myrmeleon gerlindae; C, Myrmeleon punicanus; D, Myrmeleon bore; E, Myrmeleon inconspicuus; F, Myrmeleon mariaemathildae; G, Myrmeleon hyalinus; H, Myrmeleon fasciatus; I, Euroleon nostras.

FIGURE 6. IX abdominal sternite of 3rd instar larvae of Myrmeleontini, ventral view; A, Myrmeleon gerlindae; B, Myrmeleon punicanus; C, Myrmeleon formicarius; D, Myrmeleon bore; E, Myrmeleon inconspicuus; F, Myrmeleon mariaemathildae; G, Myrmeleon hyalinus; H, Myrmeleon fasciatus; I, Euroleon nostras. Scale bar: 1 mm.

FIGURE 26. Myrmeleon formicarius Linnaeus, 1767, 3rd instar larva (Italy: Lazio, Roma, Prataglia di Cervara). Dorsal (above), ventral (middle) and lateral (below) view; a–d: diagnostic characters, see species description.