CHIGGERS — FARRELL 127 



1. Euschongastia lacerta Brennan 



Figure 4,a; Plates 6, 9 

 E. lacerta Brennan, 1948, pp. 465, 467-468, 477, figs. 2a-d, 9. 



Description : With the characters of the group. 



Size : Length, 330 to 350 ; width, 170 to 235. 



Shape : Oval or ovoid. 



Gnathosoma: Setae of palpal coxa, femur, and genu short, 

 with few fine setules. Dorsal seta on palpal tibia fine with few 

 setules ; lateral seta fine with one or tvvo fine setules ; ventral seta 

 with four or five fine setules. Palpal claw short, curved, stout, 

 with three prongs, median longest and heaviest, but accessories 

 stout. Tarsus small with four slender feathered setae and a tiny- 

 spur. Galeal seta fine with three to five fine setules. Cheliceral 

 base slightly longer than broad; blade rather long and straight, 

 curved at base and distal end ; tiny dorsal tooth and larger ventral 

 tooth distinct. 



Legs: Leg I with a rather strong microgenuala on the distal 

 dorsal surface and a single, fine genuala posterior to it. Tibia 

 with two small tibialae set obliquely on the distal dorsal surface 

 and a microtibiala posterior to the more distal of the two. Tarsus 

 with a stout spur on its middorsal surface and a small microspur 

 distal and slightly posterior to it; pretarsala small. Punctae few 

 on segments 4, 5, and 6, not always apparent on coxa. Leg II with 

 two short, blunt tibialae. Tarsus with a long, slender spur, a 

 comparatively long microspur proximal to the spur, and a short 

 pretarsala. Punctae few and large on coxa and segments 3, 4, 

 and 5. Leg III with a slender, curving tibiala. Coxal seta on 

 proximal half set well back from anterior margin; a few large 

 punctae on coxa. 



Scutum : About twice as wide as long. Anterior margin almost 

 straight; lateral margins concave, curving posteriorly and later- 

 ally, posterior margin generally convex, slightly concave adja- 

 cent to the posterolaterals and medially. Setae slender with fine 

 setules; anteromedian similar to anterolaterals and set well back 

 from anterior margin; posterolaterals on slight elongations. 

 Pseudostigmata near a line drawn connecting posterolaterals, 

 varying from slightly anterior to slightly posterior, set appar- 

 ently at an angle into the bases of short ridges arching over them 

 anteromedially. Sensillae long, clavate, tapering from head to 

 pedicel, widest about four-fifths the length from the base ; covered 

 with short, sharp setules which begin well down on the pedicel. 

 Punctations lacking, but a small pit or pore present medial to 

 each posterolateral seta. 



