Identity of the native South American armored scale insect species (Hemiptera: Coccomorpha: Diaspididae) widely misidentified as the North American species <i>Diaspidiotus ancylus</i> Putnam

The Putnam scale, <i>Diaspidiotus ancylus</i> Putnam, 1878 (Hemiptera: Coccomorpha: Diaspididae), a species considered to be native to North America, has frequently been reported to be present in Chile and Argentina, attacking a wide variety of orchard crops (apples, pears, olives, nectarines, grapes) and common street trees (poplar, locust). However, diagnostic DNA sequences from Chilean populations identified as <i>D. ancylus</i> differ from those of North American <i>D. ancylus</i>; instead they are identical to those reported for <i>Clavaspis patagonensis</i> Schneider, Claps, Wei, Normark & Normark, 2020, a species previously known only from a single locality in Argentina. We have examined the Chilean and Argentine specimens identified as <i>D. ancylus</i> or <i>Diaspidiotus</i> sp. in major collections in Chile, France, Argentina, and United States, and we determine that nearly all of them belong to <i>C. patagonensis</i> and none belong to <i>D. ancylus</i>. Here we provide a redescription of <i>C. patagonensis</i> with a distribution map and a guide to distinguishing it from <i>D. ancylus</i>. <i>Clavaspis patagonensis</i> occurs throughout most of Chile, from Atacama to Aysén, and in at least 3 provinces in Argentina (Neuquen, Rio Negro, Entre Rios). <i>Diaspidiotus ancylus</i> apparently does not occur in Chile. We have examined specimens of <i>C. patagonensis</i> from 18 plant families. Field surveys of diaspidids in Chile indicate that <i>C. patagonensis</i> is one of the most common species of diaspidids in the country.