Allectus. AE Antoninianus. London mint. 

IMP C ALLECTVS PF AVG, radiate, cuirassed bust right.
ADVENTVS AVG, emperor on horseback riding left, holding
sceptre, captive before the horse.

Mintmark ML. 

Unpublished reverse for the London mint. Spink 13013, 59.

Sold by Spink, auction 13013, Lot 59, June 2013.