Dragonflies and damselflies (Odonata): Damselflies typically sit with their wings together, closed over their backs. Dragonflies sit with their wings spread. Collectively over 120 species occur in the Big Thicket area. They are often associated with water where they lay their eggs. Most species have preferences in the water they frequent, such as moving water vs. still water, streams, ponds, marshes etc. The Needham's skimmer ("Libellula needhami") lay their eggs in flight, while the ebony jewelwing ("Calopteryx maculata") submerges for up to two hours while depositing eggs. The nymphs are aquatic. Both the larva and adults are fierce predators, feeding primarily on insects. They are frequently sexually dimorphic and males and females may have different colors and patterns. Some species like the roseate skimmer ("Orthemis ferruginea") and common green darner ("Anax junius") can be seen in their adult form year round. Others are limited to a few weeks or mouths each year like the calico pennant ("Celithemis elisa") flying April - August and Needham's skimmer ("Libellula needhami") flying May - September. The Texas emerald ("Somatochlora margarita") and the rare and sarracenia spiketail ("Cordulegaster sarracenia") are endemic to southeast Texas and adjacent areas of Louisiana.