order
                        
                      
                                    Coleoptera
                                       “Adult Beetles”
                                  
                                    Coleoptera
                                       “Larval Beetles”
                                  
                                    Diptera
                                       “True Flies”
                                  
                                    Ephemeroptera
                                       “Mayflies”
                                  
                                    Hemiptera
                                       “True Bugs”
                                  
                                    Lepidoptera
                                       “Aquatic Caterpillars, Snout Moths”
                                  
                                    Megaloptera
                                       “Alderflies, Dobsonflies, and Fishflies”
                                  
                                    Odonata
                                       “Dragonflies and Damselflies”
                                  
                                    Plecoptera
                                       “Stoneflies”
                                  
                                    Trichoptera
                                       “Caddisflies”
                                 family
                        
                     Hydropsychidae
               
            Macrostemum
            
                  “Seine-net Weaver Caddisflies”
               
      Genus Overview
                  
               
                        This is a very distinct genus of Hydropsychidae with the large flattened space on their heads.  They produce highly specialized larval retreats and capture nets.  The flattened head is thought to restrict water flow through their retreats to their direct flow to their capture nets.  There are 3 species in North America.  They tend to be in larger streams and rivers and feed off of fine particles of organic matter, phytoplankton and bacteria. 
                  
               Characteristics
                  
               POLLUTION TOLERANCE
                        Southeast: 3.6
                                 Upper Midwest: 3
                                 Midwest: 1.8
                                 Mid-Atlantic: 3
                              0 = least tolerant, 10 = most tolerant
                        FEEDING HABITS
                        
                                 Collector / Filterer
                        
                     MOVEMENT
                        
                                 Clinger
                        
                     DISTRIBUTION
                        
                                 Widespread (east of the Rocky Mtns.)
                        
                     HABITAT
                        
                                 Lotic-erosional
                        
                     Diagnostic Characters
               order
                         
                                       
                                       
                                    Prolegs With Single Hook
                                 family
                         
                                       
                                       
                                    All Nota Sclerotized
                                  
                                       
                                       
                                    Retreat
                                  
                                       
                                       
                                    Setal Fan On Prolegs
                                  
                                       
                                       
                                    Ventral Branched Abdominal Gills
                                 genus
                         
                                       
                                       
                                    Carina
                                 
                  + Expanded Character List
                  
                     
               
            
                        Order:
                           Larvae: Wings/wing pads absent. Eye spots present, but compound eyes absent. Antennae usually small, inconspicuous. Three pairs of segmented legs present on thorax. Pair of anal prolegs, each with single hook, located on last abdominal segment. Larvae can be free-living, in silken retreats attached to substrate, or in usually-portable tubes or cases made of sand, rocks, or plant material.
                     
                     
                        Family:
                           Pro-, meso-, and metanota entirely covered by sclerites. Ventral side of abdomen with rows of branched gills. Conspicuous tuft or fan of long hairs on each anal proleg. Anal claw with stout apical hook. Larvae building stationary retreats of silk, detritus, and rock fragments and add a silken net for filter feeding.
                     
                     
                        Genus:
                           Larvae up to 17.5 mm.  Large flattened head. A pair of sclerites at the base of the labrum, prominent process at the base of femur
                     
                   
            Lateral
               


