Sitobion dorsatum Richards 1967

Victor, Eastop, F. & Blackman, Roger L., 2005, Some new synonyms in Aphididae (Hemiptera: Sternorrhyncha), Zootaxa 1089, pp. 1-36 : 31

Sitobion dorsatum Richards 1967 to Aulacorthum

This species was described in Aulacorthum but transferred to Sitobion by Eastop and Hille Ris Lambers (1976). The dorsal cuticle is sclerotic as in Sitobion and the siphunculi have several rows of subapical reticulation, but these features are also found in some Aulacorthum . However unlike any Sitobion the antennal tubercles are very well developed and steep­sided, and the ventral side of the head is spiculose. The karyotype (three samples collected by Cho­kai Chan), is 2n=12, commonly found in Aulacorthum , whereas most Sitobion have 2n=18. The alata , uncharacteristically for both genera, has a dark dorsal abdominal patch, which might indicate a closer affinity to Neomyzus , except that the hind tibiae are not spinulose. We conclude that this species should be returned to Aulacorthum , in spite of some features atypical of that genus.