1969] 
Evans - — Cretaceous Wasps 
255 
assume that this wasp had a wing span of about 12 mm and a body 
length of 7-9 mm. No color pattern is evident on the wing. 
Specimen from Wadhurst Clay, Quarry Hill Pit, Tunbridge, 
England (Lower Cretaceous). 1 Collected by R. A. Crowson in 
1939; MCZ no. 6312. 
Lisponema, new genus 
Based on a single specimen in amber in nearly perfect condition 
except lacking nearly all of the head (Figs. 2, 3). The more striking 
features are as follows: body and legs slender, the latter devoid of 
spines; tibial spur formula 1-1-2; claws weakly dentate; mesoscutum 
large, parapsidal furrows distinct, notauli vaguely indicated ; abdomen 
slender, sessile; fore wings with a very large stigma; marginal cell 
(cell Ri) measured along wing margin about as long as stigma, its 
apex curved away from wing margin and weakly appendiculate ; two 
submarginal cells and two discoidal cells present (veins 3 r-m and 
2 m-cu wholly absent), and in general veins and cells far removed 
from outer wing margin; hind wing with six rather large hamuli 
visible, veins Rs and M not extending beyond r-m, submedian cell 
elongate, its outer end (cu-a) rounded up to meet media at the 
origin of cubitus (i.e., where M passes up to meet r-m). 
Type species: Lisponema singularis , new species 
The name Lisponema is an anagram of Spilomena , the living genus 
which it resembles most closely; however, it might equally well be 
taken to mean “smooth thread” (Greek lispos T nema) , with 
reference to the very slender, smooth legs. This genus resembles 
Spilomena so closely that it can be uniquivocally assigned to the 
family Sphecidae, subfamily Pemphredoninae, and to that section 
of the subfamily that includes Spilomena , Microstigmus, Ammo- 
planus, and certain other genera. While the Pemphredoninae rank 
as one of the more generalized subfamilies of Sphecidae, these genera 
are considered to represent one of its more specialized elements. The 
specializations extend to larval characters and, in Microstigmus , to 
nest type and probable sociality (Matthews, 1968). The species of 
Spilomena are solitary wasps that nest in cavities in wood and prey 
upon thrips. The very close resemblance of Lisponema to members 
of this genus suggests that it, too, nested in some type of pre-existing 
cavities; the slender, smooth legs, in particular, indicate that it did 
not dig in the soil. 
Hhese relatively poorly known deposits are described by White (1928). 
The insect fragments from these beds have evidently not been monographed. 
