NEOTROPICAL PLATYRHACID MILLIPEDS — HOFFMAN 25 



wider on the sides; prozonites uniformly finely granular; pleural areas 

 of metazonites more coarsely granular and beset with numerous 

 rounded to conical tubercules, those immediately above the legs 

 hypertrophied into a field of large, prominent, acute denticles, spines, 

 and bidentate cones, some exceeding caudal margin of segment. 

 Stigmata large, swollen, followed on most segments by a similar 

 appearing protuberance adjacent to the base of the posterior leg pair. 



Sternal areas of metazonites produced into a high, abrupt platform 

 (podosternum) accommodating the coxal sockets, with low, obtusely 

 conical, caudolaterally directed knobs at the base of each leg; podo- 

 sterna with median cruciform depressions entirely glabrous. 



Legs long (up to 8.5 mm.), distal half of femora visible beyond 

 paranota in dorsal aspect, the joints cylindrical, setose, in decreasing 

 order of length 3-6-2-4-5-1. Tarsal claws long, slightly arcuate, 

 slender, almost half as long as tarsi and fully as long as prefemora. 



Sterna produced into small acute cones at the bases of legs 4-7, 

 the sternum of segment 6 depressed and widened to accommodate 

 tips of the gonopods. 



Seminal lobes of second coxae hemispherical w4th a small distal 

 median papilla. 



Sternal aperture of segment 7 ovoid, with lateral and caudal raised 

 rims, anteriorly transgressing only slightly into the prozonite. Gono- 

 pods rather small, slender, directed cephalad and parallel to each 

 other. Coxites and telopodites of the form typical for the genus, 

 apparently a little different in the form of the prefemur on the coxal 

 side where it is broadened and produced into a slight knob. Femur 

 long and slender, virtually parallel sided in mesial aspect, grading 

 into a thin laminate tibiotarsus that is drawn out into an acute tip, 

 the terminal third turned over somewhat mesiad. Solenomerite 

 directed distad parallel to the tibiotarsus, gradually attenuated, very 

 sHghtly sinuate. 



Remarks: This species is described and named as new with some 

 diffidence because of nearly a dozen inadequately documented specific 

 names based on platyrhacids from the northern Andes in Colimibia 

 and Ecuador. As long as these names remain inquirendae, it certainly 

 seems best to treat species from that region as new and give full 

 descriptions, rather than cause a series of misidentifications by 

 endeavoring to assign specimens to any of the doubtful existing names. 



One known species rather closely approximates Platyrhacus acantho- 

 pleurus. This is one from Sao Paulo do Olivencia, on the Amazon 

 River in western Brazil, which was identified by Attems (1938, p. 234) 

 as Polydesmus bilineatus Lucas (1840). However, the creature origi- 

 nally described by Lucas was said to have come from "Mexico," 

 and its description does not inspire much confidence in future recogni- 



