Material and methods
For the present study 407 adults of Trichomeloe were examined: 85 of T. chrysocomus (Miller, 1861); 27 (holotype included) of T. conicicollis (Reitter, 1907); 96 (holotype and 1 paratype included) of T. deflexus (Reitter, 1889); 14 (holotype and 11 paratypes included) of T. mesopotamicus n. sp.; 7 (holotype and 1 paratype of the synonym frivaldszky included) of T. ottomanus (Pliginskji, 1914); 173 of T. sericellus (Reiche, 1857); 5 (holotype and 3 paratypes included) of T. syriacus n. sp. We tried to examine the holotype and the paratypus of T. ovatus, probably both preserved in the Tajikistan University Museum, but were unsuccessful and consequently no specimens of T. ovatus were studied.
Ecological observation on habitat preference, altitudinal range, host plants, etc., were obtained in the field in Turkey, Syria, Palestine, Jordan; other records have been deduced from the literature or from collection labels.
One female of T. syriacus from Syria, Palmyra (collected on January 30th 1998 by P. De Salvo), laid (on February 4th 1998) one egg mass in the rearing box; eggs were kept in a thermostatic cell with photoperiodic control under ca 24-25°C. First instar larvae hatched two and half weeks later in Italy, at University laboratory, in two consecutive days (February 21/22nd 1998), and then fixed in 70% ethanol. One female of T. chrysocomus from Jordan, Kérak-Ca Province, Wadi Al Hasa (collected on January 2nd 2005 by P. Bombi), laid (on January 17th 2005) one egg mass in the rearing box; eggs were kept in the same conditions described above and first instar larvae hatched in two days (January 26 and 28th 2005).
The description of the first instar larva of T. syriacus from Palmyra is based on 15 triungulins preserved in 70% ethanol in the CB (vial 398), one of which cleared and mounted in Canada balsam on slide M340, and some prepared for SEM microscopy, after critical point dehydration and gold sputtering. Additionally, 2 triungulins of T. chrysocomus, from Palestine mounted on slide M183 (now in CB, from several BMNH specimens in 70% ethanol), and several triungulins from Wadi Al Hasa preserved in 70% ethanol in the CB (vials 546, 547), some of which prepared for SEM microscopy, have been observed for comparison. The morphological analyses were made by using a Leitz Laborlux S light microscope and a Philips XL30 scanning electron microscope (L.I.M.E., University “Roma Tre”, Rome). The terminology of larval structures follows MacSwain (1956), Lawrence (1991), and Bologna and Pinto (2001). Certain characters used in the larval chaetotaxy were adopted from notational conventions suggested by Selander (1990) and Bologna and Di Giulio (2002).