Margarinotus (Ptomister) mormon (Casey, 1893)

Caterino, Michael S., 2010, A Review of California Margarinotus Marseul (Coleoptera: Histeridae: Histerinae: Histerini), with Descriptions of Two New Species, The Coleopterists Bulletin 64 (1), pp. 1-12 : 11

Margarinotus (Ptomister) mormon (Casey, 1893)

Hister mormon Casey 1893: 543 .

Hister mormoni (lapsus calami); Lewis 1905: 30. Margarinotus mormon (Casey) ; Wenzel 1944: 126.

Remarks. Mazur (1997) reported M. mormon from California, probably based on a series (including FMNH-INS-0000032070) identified by Wenzel as this species. This series, labeled as having been collected in Laguna, San Diego Co., CA in 1929, appears to be Margarinotus hudsonicus (Casey) , and shares few characters with M. mormon (at least as described by Casey; the type was not examined). It is not clear if M. hudsonicus should be considered part of the California fauna or not, as no other records or specimens have been encountered. I believe it to be a probable mislabelling, or less probably an unsuccessful introduction to the state. All of the specimens with these data were evidently unmounted at some point (formerly pinned, then pointed) and it is conceivable that they were relabeled inaccurately in the process. Wenzel (unpublished) also reports M. mormon from several localities in eastern California (in and around the Owens Valley). I consider these to represent M. fractifrons (though these are also similar in some characters to M. hudsonicus ). Margarinotus mormoni was described and has only reliably been reported from Utah. These three species are, however, all very closely related and not very clearly distinguished where they meet (Wenzel unpublished). They may be separate offshoots of a recent ancestor, or be experiencing significant character introgression and/or hybridization among them.