The Chonaphini 123 



(Figs. 4-6). Thus, although taxonomically important features occur 

 on several parts of the prefemoral process, all four species of Chonaphe 

 can be diagnosed solely from the apical configuration. It seems ironic 

 that such significance can accrue to such a minute part of this massive 

 structure. 



Though large, expanded, and laminate, the prefemoral process 

 of Semionellus (Figs. 30-31) has a different configuration from that 

 of Chonaphe. Instead of being upright, it bends strongly, at about a 

 right angle, near 1/3 length and exhibits cupulate flanges on the medial 

 surface proximal and distal to this bend. There is no ledge or shield 

 as in Chonaphe, but occasionally the acropodite extends through the 

 concavity of the proximal flange. The margins of these flanges, particularly 

 the proximal one, are highly irregular and sometimes jagged, with 

 minute serrations, larger teeth, and in some individuals, a secondary 

 proximal flange, also marginally irregular, arising from the basal lamella; 

 the distal flange is further ornamented by a strong, distally directed 

 spine from the caudal margin. The distal 1/3 of the prefemoral process 

 expands to a subacuminate tip on the inner distal corner, but its 

 principal characteristic is a dense pilosity that arises from the inner 

 and apical margins and nearly obliterates the tip. There are two kinds 

 of hairs — long, relatively straight ones arising marginally and submargin- 

 ally, and short, curved ones that arise from an overhanging ledge on 

 both the medial and lateral sides and extend at most only to the level 

 of the first hairs. These distal hairs, apomorphic for Semionellus, are 

 unique not only in the Chonaphini but also in the family Xystodemidae. 

 I know of no other xystodesmid genus with hairs on either the prefemoral 

 process or acropodite. 



The other type of prefemoral process is the narrow projection, 

 which is blade-like, at least basally, in Montaphe elrodi and Metaxycheir, 

 and subacicular in Tubaphe. It curves generally bisinuately, lacks 

 secondary structures in Metaxycheir (Figs. 52-53), and subtends a 

 variable arc and possesses modifications in Montaphe and Tubaphe 

 (Figs. 35-38, 47-48). The projection curves gently and displays minute 

 apical barbules from the inner margin in Tubaphe (Figs. 47-48), the 

 latter being shared with Montaphe elrodi, in which the barbs are 

 strongly pronounced and extend proximad on the stem of the projection, 

 though still clustered apically (Figs. 35-38). In M. elrodi the prefemoral 

 process bends or curves dorsad near midlength, extending well beyond 

 the acropodal curvature, excepting individuals in which the latter is 

 distended (Fig. 38), and tapering smoothly and continuously to a sub- 

 acuminate tip. The barbs are located distad, and proximal to the bend 



