A new bee genus from the pampas of eastern Argentina, with appended notes on the classification of “ paracolletines ” (Hymenoptera: Colletidae) Author Engel, Michael S. Division of Entomology, Natural History Museum, and Department of Ecology & Evolutionary Biology, 1501 Crestline Drive - Suite 140, University of Kansas, Lawrence, Kansas 66045 - 4415, USA (msengel @ ku. edu). & Division of Invertebrate Zoölogy, American Museum of Natural History, Central Park West at 79 Street, New York, New York 10024 - 5192, USA. Author Gonzalez, Victor H. Undergraduate Biology, and Department of Ecology & Evolutionary Biology, 1200 Sunnyside Avenue, University of Kansas, Lawrence, Kansas 66045, USA (vhgonza @ ku. edu). text Journal of Melittology 2022 2022-01-24 2022 109 1 39 http://dx.doi.org/10.17161/jom.i109.16424 journal article 10.17161/jom.i109.16424 2325-4467 13146121 6C96BAB7-7AF6-4B8B-A2EF-08BD9F3A1344 Rhamphocolletes Engel , new genus ZooBank: urn:lsid:zoobank.org:act: 2D43C99F-5488-4BAB-9800-18B31F7F788B TYPE SPECIES : Leioproctus ( Leioproctus ) macmillani Houston, 1991 . DIAGNOSIS: This genus corresponds to Houston’s (1991) macmillani species group, fully characterized by that author. Particularly noteworthy traits include: frons rugulose; malar space much greater than basal mandibular width; flagellomeres II–X of male with cup-shaped, ventral, prong, flagellomeres I and XI with simple ventral lobe; probasitarsus of female with spines ventrally and long, curved bristles dorsally; male sternum VII with two apical lobes. ETYMOLOGY: The new genus-group name is a combination of the Ancient Greek rhámphos ( ῥᾰ́μφος , meaning, “beak”) and kollitís ( κολλητής , meaning, “gluer” or “one who glues"). The gender of the name is masculine.