235 

 Chandler: Aquatic Neuroptera 



surface film, swim by curling the abdomen ventrally 

 and snapping it out straight, float or sink at will, or 

 wander about on the bottom. The sponge host is found 

 in one of these ways. Once settled upon a sponge, the 

 larvae do not readily leave it unless the sponge dies. 

 They frequently enter the ostioles of the sponge. The 

 first instar larva commonly feeds for one- half to two 

 minutes, rests or wanders about for one to five min- 

 utes, then reinserts its mouth parts for another meal. 

 The sucking mouth parts consist of the mandibles and 

 maxillae on each side joined so as to make a tube. 

 The right and left pairs can also be joined. Color 

 varies from green to yellow-brown depending somewhat 

 on the color of the sponge. The mature third instar 

 larvae (fig. 9:1) crawl or swim to an object upon 

 which they can emerge from the water. Most larvae 

 emerge from one to five hours after dark. They may 

 travel as far as fifty feet before selecting a site to 

 spin a cocoon, usually in a somewhat protected 

 location. The larvae take a firm stance and do not 

 move their feet while spinning the outer net. The 

 tenth abdominal segment is modified into a spinneret 

 with the silk exuding from the anus. The spinning is 

 accomplished by bending the abdomen this way and 

 that with some telescopic movement. The resulting 

 hemispherical outer net has a radius about the same 

 length as that of the abdomen (fig. 9:2). In Climacia 

 this outer net has a delicate hexagonal mesh whereas 

 in Sisyra the fibers are merely crisscrossed. The 

 cocoon is about half the diameter of the outer net 

 and is composed of crisscrossed fibers in both genera. 

 The cast pupal skin is wadded into the end of the 

 cocoon. The sex of the pupa can be determined by 

 examining the genitalia. The mandibles are heavily 

 sclerotized and used by the pupa to chew its way out 

 of the cocoon and net. The appendages are immovable 

 until just before emergence, which usually occurs 

 after sunset. Within two hours the insect assumes 

 its adult form and color (fig. 9:3). Shortly thereafter 

 a fecal pellet is deposited which probably contains 

 the accumulated waste solids from the entire previous 

 existence, since in the larvae the alimentary tract 

 beyond the stomach is atrophied or modified into 

 silk glands. Little is known of the food habits of the 

 adults; fecal pellets of captured adults were found 

 to be largely composed of pollen grains. Eggs were 

 obtained from laboratory-reared specimens fed only 

 on a gum drop and water. Adults live for two weeks or 

 more and mating may occur at any time during this 

 period, usually from dusk until midnight. Oviposition 

 takes place two to six hours after sunset, and forty- 

 five or more eggs are laid by each female. Two or 

 three complete cycles may occur each year. Winter is 

 probably passed in the larval stage. 



Fig. 9:3. Adult female Climacia (Brown, 1952). 



Members of this family are exposed to the usual 

 physical hazards of the environment and to predators 

 both in the water and upon the land. Climacia at 

 least serves as a host for Sisyridivora cavigena Gahan 

 (Hymenoptora, Chalcidoidea), a small black parasitic 

 wasp. By means of a long ovipositor, this wasp is 

 able to pierce the net and cocoon, sting the larva or 

 pupa, and lay its eggs on it. Sisyridivora cavigena 

 was described from Ohio on Climacia areolaris. The 

 same species, or a nearly related species, was found 

 in pupal cases of C. californica Chandler at Clear 

 Lake, California. 



Habitat and distribution. — Spongilla-flies are likely 

 to occur wherever the proper species of sponge is to 

 be found. Most larval records are from Spongilla 

 fragilis, but other species of Spongilla and Ephydatia 

 have been listed as hosts. Some genera of fresh-water 

 sponges are notably free of these parasites even 

 when nearby Spongilla are heavily infested. Brown 

 (1951) noted that in his study area, Spongilla fragilis 

 occurred in the cool, clean lake and in a relatively 

 warm, polluted pond; but the former yielded only 

 Climacia and the latter Sisyra. Larvae may occa- 

 sionally be found feeding on Bryozoa or Algae, but 

 sponges are always present nearby. Adults are usually 

 taken at lights or by sweeping bushes near the place 

 of emergence. 



Sisyra contains nineteen species scattered through- 

 out the world except Australia. Only one species, 



Fig. 9:2. Larva of Climacia spinning a net (Brown, 1952). 



Fig. 9:4. Wing of Climacia californica (H. P. Chandler, original). 



