Neuroleon egenus (Navás, 1914)

Badano, Davide & Pantaleoni, Roberto Antonio, 2014, The larvae of European Myrmeleontidae (Neuroptera), Zootaxa 3762 (1), pp. 1-71 : 30

Neuroleon egenus (Navás, 1914)

( Fig. 15 )

The larva of N. egenus was described and illustrated by Steffan (1965, 1971, 1975), in the first description wrongly identified as N. nemausiensis (see under this species).

Examined specimens. France. Hérault, Carnon la plage, sand dunes, VII.2011 (D. Badano), 4 L3 laboratoryreared to adult. Gard, Beauvoisin, relict sand dunes, VIII.2011 (D. Badano), 4 L3 and 2 L3 laboratory-reared to adult. Gard, Générac, relict sand dunes, VIII.2011 (D. Badano), 2 L3 . Italy. Liguria, Cipressa ( Imperia ), open pine wood, IX.2010 (D. Badano), 1 L3. Lazio, Roma, Insugherata, IX.2010 (A. Alfonsi & C. Cesaroni), 3 L3. Sardinia, Sassari (Sassari), urban park, XI.2011 (D. Badano), 1 L3. Sardinia, Platamona (Sassari), pine wood on back dunes, XII.2010 (D. Badano), 4 L3. Sardinia, Alghero (Sassari), pine wood on back dunes, V.2010 (D. Badano), 1 L3 laboratory-reared to adult. Sardinia, Dolianova (Cagliari), cork oak wood, V.2010 (D. Badano), 2 L3 and 1 L3 laboratory-reared to adult . Greece. Corfu, Acharavi , scrubland, V.2012 (D. Badano), 1 L3 .

Description of 3 rd instar larva. Size (based on 18 specimens): BL 8.20 mm; HL 1.96 mm (1.68–2.22), HW 1.58 mm (1.38–1.99), ML 1.74 mm (1.41–1.99), HW/HL 0.81, ML/HL 0.89. General colouring brown with dark brown markings, ventral side paler with a dark pattern; head capsule with small markings on the dorsal side, antennal pits bordered by dark brown markings, occipital area with a V-shaped marking, lateral sides with conspicuous dark markings ( Fig. 15b ), ventral side of the head capsule with dark spots bordering the gula and a median pair of short parallel stripes (slightly faded in some individuals) ( Fig. 15c ); labial palpi pale brown ( Fig. 15d ); mandibles brown with a dark brown spot at the base; legs pale; setae of the body black. Head longer than wide; dorsal side of the head capsule covered by short and relatively sparse dolichasters; mandibles slightly shorter than the head capsule ( Fig. 15a ); interdental mandibular setae: (+4)(1)(1–rarely 2)(0). Mesothoracic spiracles brown. IX abdominal sternite with rastra each bearing 4 digging setae, internal seta is shorter than the others ( Fig. 15e ).

Bio-ecology. N. egenus is a relatively common and euryoecious species living in a diverse array of Mediterranean environments, from dunes to xeric woods, although it is associated with the presence of arboreal vegetation. The larvae require protected and shaded condition, such as at the base of trees where they can be noticeably abundant, buried into vegetal debris among roots. Larvae of this antlion also colonize other sheltered microhabitats, such as under rock overhangs or under shrubs. The larvae of this species are often found in small groups, in many cases composed by coetaneous specimens, probably suggesting a weak or absent dispersal behaviour from the original site of oviposition.

Distribution. Widespread along the Mediterranean Basin.

Remarks. The short parallel stripes on the ventral side of the head easily permit to discriminate this species from the congeners.

Figures

FIGURE 15. Neuroleon egenus (Navás, 1915), 3rd instar larva (Italy: Liguria, Cipressa). Dorsal (above), ventral (middle) and lateral (below) view; a–e: diagnostic characters, see species description.