Andrena Nesting Biology 
145 
Description of Prepupa (Fig. 2). — Cream colored, C-shaped, 5.2 mm to 
7.3 mm long (N = 15), with prominent transverse, dorsolateral tubercles. 
Intersegmental furrows distinct. Head lacking setae, weakly sclerotized; 
cleavage lines indistinct. Vertex rounded with two small paramedian con- 
vexities. Antennae represented by low convexities arising from large, 
rounded prominences. Parietal bands not apparent. Posterior thickening 
of head capsules inconspicuous; hypostomal and pleurostomal thicken- 
ings more pronounced. Posterior tentorial pits distinct. Epistomal suture 
weak; labroclypeal suture distinct. Labrum bearing two small convexities 
with clustered sensillae; tubercles absent. Mandibles robust; moderately 
sclerotized, most heavily at cusp; apex attenuate and sharply pointed; up- 
per apical margin with dense row of teeth; lower margin with row of 
smaller denticles; ventral surface with row of denticles near lower margin, 
denticles and spicules scattered distally; adductor apodeme twice as long 
as abductor apodeme. Maxillae with indistinct separation of cardines and 
stipites. Maxillary palpi very pronounced, twice as large as labial palpi. 
Labium with prementum and postmentum undefined. Salivary opening a 
U-shaped slit. Body naked; spiracular atria extending slightly above body 
surface. 
Predators and Parasites. — On 2 January 1977, three adult Sphecodes sp. 
were noted in the nesting area, two of which were observed leaving 
Andrena nest burrows. Members of this genus are frequently nest parasites 
of bees (Bohart 1970). Also present at Andrena nest entrances were ants of 
the genus Solenopsis, and an adult female Andrena was collected on 3 
January 1977 with an ant firmly grasping both right wings (Fig. 3). The 
bee crawled from a nest hole, attempted flight, then crawled along the 
ground dragging the ant. 
Fig. 3. Female Andrena miserabilis with Solenopsis attached to wings. 
