Maxillaria lehmannii Rchb.f., Otia Bot. Hamburg.: 8 (1878).This name is accepted.
Distribution: Ecuador
number 20135115 PR
this is a tough one. this is one - eric splits the bunch with out any real points differentiating them- I am pretty sure we could say it is not lehmanni based on the lip not being folded at the area that would be the sulcus between the lateral lobes and the midlobes ( based on the drawing of the type below) --
Maxillaria christensonii D.E.Benn., Brittonia 50: 187 (1998). This name is accepted.--this is supposed to have a three lobed lip
Maxillaria irrorata Rchb.f., Gard. Chron., n.s., 20: 102 (1883). This name is accepted.
Maxillaria amesiana auct., Gard. Chron. 1891(1): 502 (1891).This name is unplaced(per Kew).
eric lists this a a synonmym of M. amesiana -Maxillaria mooreana Rolfe, Bull. Misc. Inform. Kew 1895: 36 (1895).This name is unplaced(per Kew).
I am inclined to go with M. irrorata( as a lumper), though amesiana is probably as earlier name but Kew does not like the name(if they are synonyms). If we say they are different as Eric did- Eric felt the M. irrorata did not have the stripes on the petals- stripes vs. no stripes were big for Eric. To be in concurrence with Eric I guess we would go with amesiana.

irrorata type drawing left

irrorata type drawing left
this to the right is lehmannii

Maxillaria lehmannii award 20135115 has been confirmed to be Maxillaria amesiana by SITF (Jan 2014).