Key to Genera in the Subfamilies Diamesinae, Prodiamesinae, Podonominae and Orthocladiinae

Recommended Citation:
Walker, I. R., 1997. Key to genera in the subfamilies Diamesinae, Prodiamesinae, Podonominae and Orthocladiinae Part II. In: I. R. Walker (Ed.), The WWW Field Guide to Subfossil Midges. (http://www.sci.ouc.bc.ca/fwsc/iwalker/chironomid/orthocladiinae/orthkey2.htm)

Last Update: 11 June 1997

©1997 Ian R. Walker. ALL RIGHTS RESERVED

1. • a) Mentum with pronounced bands of greater and lesser sclerotisation in lateral regions of mentum; ventromental plates not overlapping mental teeth; head capsule yellowish to brown (Fig. 1)
     .............................................................................Eukiefferiella/Tvetenia
     
     
   • b) Mentum without pronounced sclerotisation banding in lateral regions of mentum; ventromental plates may or may not overlap teeth of mentum; head capsule pigmentation transparent to yellowish or brown (Fig. 2, 3)
     .............................................................................2.
   
   
   
   
2. • a) Median mental tooth with 2 pronounced median points, weakly pigmented; first 2 pairs of lateral teeth lighter in colour than subsequent pairs; lateral teeth with truncated appearance (Fig. 2)
     .............................................................................Nanocladius
     
     
   • b) Median mental tooth without 2 pronounced median points, weakly to strongly pigmented (Fig. 3); if first 2 pairs of lateral teeth are lighter in colour than subsequent pairs, then lateral teeth without truncated appearance
     .............................................................................3.
   
   
   
   
3. • a) Mentum with odd number of teeth; median tooth without median notch and distinctly broader (2 X or more) than any lateral tooth (Fig. 3).
     .............................................................................Part III.
     
     
   • b) Mentum with even number of teeth (Fig. 5); or if mentum has odd number of teeth, then median tooth either medially notched, or not distinctly broader than any lateral tooth (Fig. 4).
     .............................................................................Part IV.
   
   
   
   

Fig. 1. Eukiefferiella/Tvetenia.

Fig. 2. Nanocladius

Fig. 3. Psectrocladius (Monopsectrocladius).

Fig. 4. Corynoneura/Thienemanniella.

Fig. 5. Heterotanytarsus.