The Paala Formation is tentatively interpreted as an equivalent of the Sablinka Formation in northwestern Russia and is referred to the Paradoxides
paradoxissimus and P.
Don McKay's Paradoxides (2012) is perhaps the most accomplished collection here, if not the sexiest (though if subsections were to be employed in this review, the section dedicated to McKay could be called Kinky Boots).
For most of Paradoxides McKay is preoccupied with concerns of a higher order, namely, the very problem that tortured Coleridge in "Kubla Khan": how to capture in words a thought, emotion, moment, or place so that another person can experience it.
Somewhat more poetically, paradoxides prove that "here" was at one time somewhere else, and will be again.
Bridger (1981, 1982), basado en el hallazgo de Paradoxides (Rushton, 1963) en un canto rodado de las arenitas de la Formacion Duda, confirma la presenciadel Cambrico en la region del Guape.
Paradoxides from Colombia, Geological Magazine, 100: 255-257.
Cleve (Avendano-Sanchez & Sotomayor-Navarro, 1982; Figueroa-Torres, 1990; Suchil-Vilchis, 1990; Zamudio-Resendiz, 1998; Aquino-Cruz, 2002; Estradas-Romero, 2004).