ATOPETHOLID MILLIPEDS — HOFFMAN AND ORCUTT 145 



Onychelus jaegeri Chamberlin 



Onychelus jaegeri Chamberlin, 1947b, p. 50, figs. 54, 55 (male holotype, Acad. 

 Nat. Sci. Philadelphia 9972, from the Indio Mudhills, 10 miles northeast of 

 Palm Springs, Riverside County, California, collected in November 1946, by 

 Smith and Jaeger). 



Gosichelus jaegeri Chamberlin, 1949, p. 168. 



Genus Saussiirobolus Carl 



Saussurobolus Carl, 1919, p. 389. 



Type species: Julus nietanus Saussure, by original designation. 



Diagnosis: A genus of small atopetholids most closely related to 

 Onychelus, from which it differs in the presence of elongated coxal 

 processes from the thh-d legs of the males, in the much less produced 

 sternite of the anterior gonopods, and in the shorter and simpler 

 telopodite of the posterior gonopods. 



Discussion: The type species of this genus was first described in 

 Julus, and was later tentatively placed by Pocock (1910) in his genus 

 Cyclothyro'phorus. At that time only a single family of spii'oboloids 

 was recognized, and the first consideration of the species subsequent to 

 Brolemann's 1914 essay on the classification of the order was given by 

 Johann Carl, who restudied Saussure's types and established the 

 genus Saussurobolus. Concerning its systematic position, he wrote 

 (1919, p. 390): 



En depit de I'absence, reele ou apparente, de I'ampoule et de la rainure seminales 

 [of the posterior gonopod], je crois devoir classer Saussurobolus dans la familie des 

 Trigoniulidae, oil il occupe cependant ime place isolee a cause de la structure du 

 coxite, de la position et de la forme des poches tracheennes. Le nombre des 

 fossettes labiales et la forme des valves anales constituent des caractferes g^n^riques 

 de second ordre. 



In his classification Attems (1926) accepted Carl's disposition of the 

 genus, and placed it with other trigoniulid genera. To the best of our 

 knowledge, Saussurobolus has not been subsequently mentioned in the 

 literature. 



There now seems to be little or no basis for considering the genus to 

 be related to the highly specialized trigoniulids any more so than to 

 any of the other spiroboloid families. 



Occurring at the southern extremity of the Mexican Plateau, the 

 species of Saussurobolus are the southernmost known representatives 

 of the family, and may prove to be very numerous when that region 

 has been thorouglily collected. Two species are known with as- 

 sm'ance, and a third, originally described in Arinolus, appears to be 

 congeneric with S. nietanus in structural details. Likewise known 

 from southern Mexico, the species is here tentatively referred to the 

 present genus. 



