146 
Psyche 
[September 
length 6-8 mm., elongate, more or less glabrous, convex; 
southeastern Kentucky (Estill, Jackson, Rockcastle, 
Pulaski, Clinton, Wayne, and McCreary counties) and 
adjacent Tennessee (Fentress County) 
Darlingtonea Valentine 
Anterior tibia rather densely pubescent on external face; 
anterior apical puncture setigerous, or if absent (Adair 
County, Kentucky), then posterior discal puncture also 
absent (+++, +O + , 00 +, or +00) 12 
12(11). Antenna as long as body, attaining elytral apexes when 
laid back; length 5. 5-7.0 mm.; head and mandibles very 
large, all appendages elongate and slender; anterior discal 
punctures of elytra at level of second umbilicate AND 
prehumeral borders sharply oblique to mid-line; Cum- 
berland plateau margin from Jackson County, Kentucky, 
southwestward to Van Buren County, Tennessee 
Nelsonites Valentine 
13(12). Right mandible with retinaculum 5-tuberculate, anterior 
two and posterior three teeth separated by a deep 
emargination ; apex of aedeagus more or less umbonate 
in ventral view, transfer apparatus a single median 
ventral sclerite; length 4.5-6.O mm., form robust, elytra 
usually more or less pruinose; southeastern Kentucky 
(Jackson, Rockcastle, Pulaski, northern Wayne and 
McCreary counties) Ameroduvalius Valentine 
Right mandible with retinaculum usually 2- to 4-tuber- 
culate, without a conspicuous gap separating teeth; 
apex of aedeagus not as described ; transfer apparatus of 
one or two sclerites, placed edgewise in internal sac 
Pseud anophthal m us Jeannel 
Pseudanophthalmus appears last because it is the largest and most 
variable genus of nearctic trechines, and the key has been con- 
structed to split off the other genera one at a time. The last couplet 
is the most inconvenient for rapid sorting because it requires re- 
moving a mandible and/or an aedeagus. As a practical matter this 
can usually be avoided because most species of Pseudanophthalmus 
do not occur within the range of Ameroduvalius , but most of those 
that do are either under 4 mm. in length or have obliquely sloping 
prehumeral borders. For Pseudanophthalmus species in the same 
size range as Ameroduvalius (4-5 mm., Wayne and McCreary 
counties, Kentucky), males can be readily distinguished by the 
