Number and arrangement of gills ofA.pageiana" 



distodorsal seta long, second dorsal seta shorter, situated slightly more 

 basally; both setae thin, light; posterior surface seta long, dark, thick; 

 anterior seta shorter and lighter. 



Claw longer and thinner than on forelegs, with pointed basal spine. 

 Abdominal segment 1 shorter than following segments, with high pointed 

 dorsal process and large, blunt lateral processes covered with characteristic 

 spinules (Figure 11 ). Segments 2—8 equally wide, last 2 segments slightly 

 longer than preceding segments. Lateral line on segments 3—7 in form 

 of narrow ridge, covered with small, fine, brownish hairs. Gills on segments 

 1-7. 



Dorsal gills on segments 2—7 situated near anterior and posterior 

 margin, posterior gills situated slightly more medially than anterior gills, 

 those on segments 6 and 7 shorter and thinner than on the preceding 



segments. Pleural gills on segments 

 2—7, anterior gill situated slightly more 

 dorsal than the lateral line, posterior 

 gill on the lateral line, the spinules of 

 which become shorter and sparser, and 

 continue from the outside and from the 

 median line to the gills. Hairs of the 

 posterior, pleural gill of segment 2 

 sparse and few, lateral line absent. 

 Ventral gills on segments 1—6 or 

 1—7; anterior gill of segment 1 

 situated in the middle, near the 

 anterior margin on segments 2—6; 

 ventral gills of segments 5—7 shorter 

 than on the preceding segments. 



Anterior -margin dorsal seta of 

 abdominal segment 1 moderately large, 

 dark, larger than on the following 

 segments, situated close to the medioanal 

 seta; medioanal seta situated lateral 

 to the dorsal process, larger than the 

 other dorsal setae, as on the following segments, black, strong, on a light 

 dot; intermediate anal and lateral anal setae small, thin, situated some 

 distance from the median seta; both lateral setae well developed, thick. 



Segment 



Dorsal 



Pleural 



Ventral 



1 









1 



2 





1 





1 



3 





1 





1 



4 





1 





1 



5 





1 





1 



6 



1(0) 

 1(0) 



1 





1 



7 



1(0) 

 1(0) 



1 



2 



1(0) 



1(0) 



This description of the arrangement of the gills has been accepted since Klapilek and Siltala. The 

 numerals on the left indicate the number of the segment, beginning from the anterior to the 

 posterior end. The scheme describes the right half of the segment; the first longitudinal line on the 

 left represents the dorsal median line of the abdomen; the second longitudinal line separates the dorsal 

 from the pleural surface, the third represents the lateral line, and the fourth separates the pleural from 

 the ventral side. The left longitudinal column gives the dorsal surface of the segment; ±e middle column 

 the pleural surface, and the right column, the ventral surface. 



The other numerals indicate the number of filaments of the gill and its position on the segment. There 

 are anterior-margin and posterior-margin gills, dorsal median and ventral median gills, gills situated dorsally 

 and ventrally from the lateral line, and ventral median and ventral lateral gills. 



The lateral line of the abdomen is represented as a continuous or dotted line, which is actually 

 unnecessary, since its position between two rows of pleura!" gills is evident. A zero indicates that there 

 are sometimes no gills at this point. 



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