1989, Western Birds, Volumes 20-21, page 9,The similarly sized Burrowing Owl and Western Screech-Owl were the most allopatric of any species pair considered here; the percentage of similarity in their diets was 67%.
1995, W. Decraemer, The Family Trichodoridae: Stubby Root and Virus Vector Nematodes, page 36,For example: the body length (varies intra- and inter-specifically in the other genera of the family), the tail shape (similar exceptions are found within the genus Paratrichodorus), the more allopatric distribution (but restricted to South America as are the other monodelphic species), to a lesser extent the position of the secretory-excretory pore (similar as in three species of Paratrichodorus, but showing variation as in some specimens of e.g. P. Anthurii where the position of the S-E pore shows a wide intraspecific variability), the absence of caudal pores (exceptions are also found in Paratrichodorus).