Neuroleon nemausiensis (Borkhausen, 1791)

Badano, Davide & Pantaleoni, Roberto Antonio, 2014, The larvae of European Myrmeleontidae (Neuroptera), Zootaxa 3762 (1), pp. 1-71 : 33-35

Neuroleon nemausiensis (Borkhausen, 1791)

( Figs. 4E , 17 )

Auber (1956a) described some Neuroleon larvae collected in southern France as N. nemausiensis . Steffan (1965) wrongly attributed to N. nemausiensis the larvae of N. egenus , as stated by himself in a later paper ( Steffan 1971), at the same time acknowledging the previous description of N. nemausiensis by Auber (1956a). Nevertheless the original account of Auber (1956a) does not agree with the specimens studied here, whose identity is verified by means of the reared adults, therefore it is not possible to speculate about the identity of the larvae observed by him. Conversely Steffan (1975) illustrated a larva as N. microstenus that shows a similar head pattern to the actual N. nemausiensis , however he did not rear it for identification. Consequently this is the first reliable description of the larva of N. nemausiensis .

Examined specimens. Italy. Liguria, Bordighera (Imperia), Monte Nero , rock crevices, VIII.2010 (D. Badano) , 5 L3 and 2 L3 laboratory reared to adult. Sardinia, Alghero (Sassari), Capocaccia , juniper thicket, V.2010 (D. Badano) , 1 L3; same locality, IX.2010 , 3 L3 and 2 L3 laboratory-reared to adult; same locality, IX.2011 , 3 L3 and 2 L3 laboratory-reared to adult; same locality, V.2012 , 4 L3.

Description of 3 rd instar larva. Size (based on 16 specimens): BL 8.11 mm; HL 1.94 mm (1.80–2.23), HW 1.53 mm (1.37–1.65), ML 1.61 mm (1.46–1.80), HW/HL 0.83, ML/HL 0.79. General colouring yellowish brown with dark brown markings, ventral side very pale without contrasting dark areas; dorsal side of the head capsule with large conspicuous V-shaped dark markings ( Fig. 17b ), antennal pits shrouded with dark brown, lateral sides with long dark markings, ventral side of the head completely pale except the dark brown labial area and a pair of dark markings bordering the gula ( Fig. 17c ); labial palpi dark brown ( Fig. 17d ); mandibles dark brown with a paler median area and a basal dark brown spot; legs pale; setae of the body black. Head longer than wide; dorsal side of the head capsule thickly covered by dolichasters; mandibles comparatively thin, slightly shorter than the head capsule ( Fig. 17a ); distance between the base of the mandible and basal tooth shorter than that between the basal and apical teeth; interdental mandibular setae: (+4)(1–2)(1)(0). Mesothoracic spiracles reddish brown. IX abdominal sternite with two rastra bearing 4 digging setae of which the internal seta is the shortest ( Fig. 17e ).

Bio-ecology. N. nemausiensis is a frequent species in warm and arid sites such as open woods and scrublands. The larvae appear relatively adaptable in microhabitat choice and they were discovered under rock overhangs, at the base of shrubs and among stones, apparently showing a preference to live in small rock pockets filled with fine detritus.

Distribution. A widespread species in the western Palaearctic in areas with Mediterranean climatic influences.

Remarks. As the other Neuroleon , the larva of N. nemausiensis is distinguishable thanks to the overall body colouring and pigmentation pattern of the head.

Figures

FIGURE 4. Pronotum of 3rd instar larvae of Dendroleontini and Nemoleontini; A, Dendroleon pantherinus; B, Nemoleon notatus; C, Distoleon tetragrammicus; D, Creoleon lugdunensis; E, Neuroleon nemausiensis; F, Macronemurus appendiculatus; G, Megistopus lucasi; H, Gymnocnemia variegata. Scale bar: 1 mm.

FIGURE 17. Neuroleon nemausiensis (Borkhausen, 1791), 3rd instar larva (Italy: Sardinia, Alghero, Capo Caccia). Dorsal (above), ventral (middle) and lateral (below) view; a–e: diagnostic characters, see species description.