Myrmeleon hyalinus Olivier, 1811

(Figs. 5G, 6G, 32)

The larva of this antlion was described for the first time by Auber (1956b) and later by Willmann (1977).

Measured specimens. Italy. Sardinia, Alghero ( Sassari), under rock overhang, VIII.2010 (D. Badano & R. A. Pantaleoni), 6 L3 ; same locality, IX.2010 (D. Badano), 1 L3. Sardinia, Cagliari (Cagliari), Molentargius, sand deposits, XI.2011 (D. Badano), 3 L3. Sardinia, Chia (Cagliari), coastal dune, XI.2011 (D. Badano), 5 L3 and 1 L3 laboratory-reared to adult. Sicily, Mazara del Vallo (Trapani), Gorghi Tondi, IX.2010 (M. Romano), 5 L3 ; same locality, IX.2011, 7 L3. Sicily, Mazara del Vallo (Trapani), Capo Feto, IX.2010 (R. A. Pantaleoni), 2 L3. Sicily, Linosa Island (Agrigento), IX.2010 (A. Corso), 3 L3 . Greece. Rhodos, Tsambika, coastal dunes, XI.2010 (R. A. Pantaleoni), 1 L3 . Morocco. Tissint, III.2011 (A. Corso), 4 L3 . Tunisia. Ras Remel, V.2010 (A. Corso), 3 L3 .

Egypt. Sharm el Sheikh, IX.2010 (A. Corso), 1 L3. Feiran Oasis, IX.2010 (A. Corso), 1 L3 .

Description of 3 rd instar larva. Size (based on 40 specimens): BL 8.08 mm; HL 1.74 mm (1.44–2.00), HW 1.30 mm (1.06–1.49), ML 1.64 mm (1.38–1.91), HW/HL 0.75, ML/HL 0.94. General colouring pale ochre with dark markings, ventral side whitish with dark markings; head capsule pale with anterior dark markings, ventral side of the head completely pale except a distinctive pair of median elongated markings (slightly faded in some specimens) (Figs. 5G, 32c), lateral sides of the head pale; mandibles pale; legs pale; setae of the body black. Head noticeably longer than wide, rectangular in shape (Fig. 32b); mandibles almost as long as the head capsule (Fig. 32a); interdental mandibular setae: (7)(2–3)(2–3)(1); dorsal side of the mandible bearing few short setae, ventral side covered by sparse, short setae external to the maxilla and few setae disposed internally to the maxilla. IX abdominal sternite equipped with an anterior row of 4 digging setae and with two sessile rastra each bearing 4 digging setae of which the external pair is the longest (Figs. 6G, 32d).

Bio-ecology. M. hyalinus is a characteristic species of warm open sandy biotopes such as coastal dunes and deserts. In southern Europe, this species is common on sand beaches although it also colonizes internal sandy deposits. The larvae of M. hyalinus build the pits in exposed condition often at the base of tufts of psammophilous plants or bushes, avoiding retrodunal environments with a closer vegetation. Exceptionally this species may be found in different microhabitats such as arenaceous escarpments and overhangs.

Distribution. Widely distributed in the Palearctic region from the Canary Islands to Iran, across southern Europe and North Africa, reaching Ethiopia in the south.

Remarks. Besides body colouring, M. hyalinus is unmistakable among European Myrmeleontini due to the rectangular head shape. In Sardinia M. hyalinus rarely cohabits with M. mariaemathildae, despite they share similar habitat preferences.