European roller
"M. gracilis" is a parasite of the European roller ("Coracias garrullus") in Europe. The worms are very small being only 2.25 to 3.00 mm long. The proboscis has 10 rows each with 8 or 9 hooks with the largest hooks on the anterior portion. The ganglion at the base of the short receptacle is 360 µm long.