Castoraeschna

Carvalho, Alcimar L., Souza, Pedro Henrique R. & Calil, Eduardo R., 2006, Description of the larvae of Castoraeschna colorata (Martin, 1908) and C. longfieldae (Kimmins, 1929) (Insecta: Odonata: Aeshnidae), with a key to the known larvae of the genus, Zootaxa 1296, pp. 19-28 : 26-27

Key to the known last instar larvae of species of Castoraeschna

1 Outer and distal margins of palpal lamina forming an angle of about 85°; distal margins of palpal laminae, when the palps closed, forming an angle smaller than 10° between the pair; pair of distal hooks not overlapping when the palps closed ............. 2

­ Outer and distal margins of palpal lamina forming an angle of around 100°; distal margins of palpal laminae, when the palps closed, forming an angle larger than 50° between the pair; pair of distal hooks overlapping when the palps closed ................... 3

2 Labium, when folded, reaching anterior base of metathoracic legs; ventral carina of abdominal segment 9 with a row of spines along its length; dorso­basal process of male epiproct not reaching the midlength of appendage (central South America)........................................................................................................................... C. longfieldae

­ Labium, when folded, reaching the posterior base of mesothoracic legs; ventral carina of abdominal segment 9 with row of spines restricted to its lateral areas; dorso­basal process of male epiproct reaching the midlength of appendage (southern South America)..................................................................................................... C. decurvata

3 Distal margins of palpal laminae, when the palps closed, forming an angle of about 90° between the pair; apex of lateral spine of abdominal segment 7 reaching level of segment 8; apex of lateral spine of abdominal segment 9 reaching level of posterior border of segment 10 (central South America)............................................. C. colorata

­ Distal margins of the palpal laminae, when the palps closed, forming an angle clearly smaller than 90° between the pair; apex of lateral spine of abdominal segment 7 not reaching level of segment 8; apex of lateral spine of abdominal segment 9 reaching approximately level of middle region of segment 10.................................................... 4

4 Labium, when folded, reaching posterior margin of mesothoracic legs; distal margins of the palpal laminae, when the palps closed, forming an angle of around 50° between the pair (southeastern Brazil)........................................................................... C. castor

­ Labium, when folded, reaching the area between meso­ and metathoracic legs; distal margins of the palpal laminae, when the palps closed, forming an angle of around 65° between the pair (southern Venezuela)............................................................ C. tepuica