ATOPETHOLID MILLIPEDS — HOFFMAN AND ORCUTT 161 



Genus Scohinomus Loomis 



ScoHnomus Loomis, 1953, p. 420. 



Type species: Scohinomus serratus Loomis, by original designation. 



Diagnosis: A monotypic arinoline genus closely related to Taras- 

 colus, from which it differs chiefly in the characters mentioned in the 

 key to genera of the subfamily and discussed in the following para- 

 graph. 



Discussion: This generic name was proposed for a milliped that 

 differed from all the atopetholids known to its author by the presence 

 of scobinae on the body segments, as well as tiie presence of acute 

 spinules on the lower edge of the metazonites. The validity of the 

 name is not beyond challenge, however, for the following reasons. 

 To begin with, the fact that scobinae are not mentioned in the diagnosis 

 of Tarascolus does not mean that they are not present; in the paratypes 

 of S, serratus examined, they are quite small and rudimentary and 

 could easily be overlooked. Also, the published information on the 

 species of Tarascolus is by no means as detailed as might be desired. 



Second, there is some doubt that the presence or absence of rudi- 

 mentary scobinae is a character of generic value. In the genus 

 Chersastus of South Africa, they occur in some species but not in 

 others, a condition duplicated in Eurhinocricus of Jamaica. Finally, 

 in at least one known Jamaican rhinocricid, scobinae are present in 

 one sex but not in the other. Assuming that scobinae do not occur 

 in Tarascolus, the overall general similarity of its species with S. 

 serratus is such as to indicate a very close relationship. 



Finally, it is stated that "The gonopods bear some resemblence to 

 those of Tarascolus Chamb., but the anteriorly exposed coxal joints 

 of the posterior lobes and differently shaped inner [i.e., posterior] 

 gonopods are distinctive characters in addition to the external ones." 

 We believe that the difference in the posterior gonopods is more 

 apparent than real, and is explainable in light of the fact that the 

 gonopod of Tarascolus bolivari appears to have been credited to 

 another species in the original drawings. Furthermore, the illustra- 

 tion given by Loomis shows this organ in anterior aspect, in contrast 

 to the posterior views in Chamberlin's paper. The drawing that is 

 here presented was made from a male parat3T)e, the gonopod of 

 which was removed and studied as a microscopic preparation. The 

 drawing is so similar to figure 46 in Chamberlin's paper that the two 

 objects might have come from the same species. 



Scohinomus is retained here on the chance that all the character 

 taken in combination are actual differences, a matter that can be 

 settled b}' future examination of typical material of Tarascolus holivari. 



