230 REVISION OF THE THYNNID^E OF AUSTRALIA, II., 



185. T. basalis Sm. 



Thynnus basalis Sm., Cat. Hym. B.M. vii. p.23, 1859( C J). 

 Thynnus vastator Sm., Descr. n.sp. Hym. 158, 1879(^9). 



(J. Clypeus truncate anteriorly, finely punctured, most sparsely 

 in centre; head and thorax finely punctured-rugulose, a delicate 

 carina from below anterior ocellus ending on the interantennal 

 prominence. Scutellum punctured, median segment finely 

 rugulose, oblique, rounded at sides. Abdomen elongate, the 

 sides nearly straight, a shallow groove between first and second 

 segments beneath, a transverse impressed line near base of 

 segments 2-5 above. Basal angles of hypopygium only slightly 

 prominent. 



£. Head shining, sparsely punctured, convex, subquadrate,. 

 rounded at posterior angles. Thorax rather sparsely punctured, 

 with a little thin pubescence; pronotum nearly twice as broad as 

 long, mediau segment short, obliquely truncate posteriorly. 

 Abdomen sparsely punctured, smooth at base and apex of 

 the segments, first segment broadly depressed along apical margin, 

 leaving a raised, curved mark emarginate in the middle before 

 apex; beneath prominent at base, with an oblique, triangular 

 truncation to apex. Second segment with three transverse 

 carinas near base, succeeded by five very small transverse carinas,, 

 the apical margin slightly raised. Third and fourth segments 

 with a raised curved mark on each side, interrupted in the 

 middle of the segments. Fifth segment beneath longitudinally 

 striated. Pygidium lanceolate, very narrow, slightly widened 

 towards apex, with a longitudinal carina and the lateral margins 

 raised, forming carinas. 



Sab. — Sydney (Froggatt); Wimmera, Vic. (French); Adelaide 

 (Smith); Swan River (Smith). 



Except that typical T. basalis is a rather smaller and more 

 slender insect, I fail to find any distinction. I have not seen a 

 female from Western Australia. My descriptions are drawn, 

 from the types of T. vastator, taken at Adelaide. 



