http://www.collembola.org/key/xenylla.htm - Last updated on 2009.09.30 by Frans Janssens
Checklist of the Collembola: Key to the species of Xenylla from Belgium

This key is still under construction. Note that missing figures will be provided as soon as possible. Currently, the key is in the feasibility study phase to find out how to integrate in the checklist in a modular way a key that has been generated with DELTA.

Hans-Jürgen Schulz, Staatliches Museum für Naturkunde Görlitz, Germany
Frans Janssens, Department of Biology, University of Antwerp, Antwerp, B-2020, Belgium

Rationale

The rationale for taxa used and not used as well as subtaxonomic classification for some taxa is to be provided.

Key

Note that no distinction between subtaxa and taxa is made in the key. 

1(0). Mucro fused with dens, forming the mucrodens; dens not with 2
        setae....................................................... 2
      Mucro separated from dens; dens with 2 setae.................. 6
 
2(1). Cephalic seta c1 absent; cephalic seta c2 present............. 3
      Cephalic seta c1 present; cephalic seta c2 absent............. 5
 
3(2). Mucrodens less than twice as long as the metaclaw............. 4
      Mucrodens often more than twice as long as the metaclaw.........
         .................................................... maritima
 
4(3). Anal spines on normal papilae...................... brevisimilis
      Anal spines on very long papilae......................... grisea
 
5(2). Mucrodens with 1 seta; tibiotarsi without clavate ventral tenent
        hairs............................................... tullbergi
      Mucrodens with 1 or 2 setae; tibiotarsi with clavate ventral
        tenent hairs....................................... brevicauda
 
6(1). Metathorax with dorsal seta a2 not displaced distally relative
        to seta a1............................................. welchi
      Metathorax with dorsal seta a2 displaced distally relative to
        seta a1.............................................. humicola

Differential diagnoses

brevicauda
Mucro fused with dens, forming the mucrodens. Dens not with 2 setae. Metathorax with dorsal seta a2 displaced distally relative to seta a1 and dorsal seta p2 displaced apically relative to seta p1. Cephalic seta c1 present. Cephalic seta c2 absent. Mucrodens with 1 or 2 setae. Tibiotarsi with clavate ventral tenent hairs.

brevisimilis
Mucro fused with dens, forming the mucrodens. Dens not with 2 setae. Metathorax with dorsal seta a2 displaced distally relative to seta a1 and dorsal seta p2 displaced apically relative to seta p1. Cephalic seta c1 absent. Cephalic seta c2 present. Mucrodens less than twice as long as the metaclaw. Anal spines on normal papilae.

grisea
Mucro fused with dens, forming the mucrodens. Dens not with 2 setae. Metathorax with dorsal seta a2 displaced distally relative to seta a1 and dorsal seta p2 displaced apically relative to seta p1. Cephalic seta c1 absent. Cephalic seta c2 present. Mucrodens less than twice as long as the metaclaw. Anal spines on very long papilae.

humicola
Mucro separated from dens. Dens with 2 setae. Metathorax with dorsal seta a2 displaced distally relative to seta a1 or mesothorax and metathorax with dorsal central setae in 3 rows. Metathorax with dorsal seta a2 displaced distally relative to seta a1.

maritima
Mucro fused with dens, forming the mucrodens. Dens not with 2 setae. Metathorax with dorsal seta a2 displaced distally relative to seta a1 and dorsal seta p2 displaced apically relative to seta p1. Cephalic seta c1 absent. Cephalic seta c2 present. Mucrodens often more than twice as long as the metaclaw.

tullbergi
Mucro fused with dens, forming the mucrodens. Dens not with 2 setae. Metathorax with dorsal seta a2 displaced distally relative to seta a1 and dorsal seta p2 displaced apically relative to seta p1. Cephalic seta c1 present. Cephalic seta c2 absent. Mucrodens with 1 seta. Tibiotarsi without clavate ventral tenent hairs.

welchi
Mucro separated from dens. Dens with 2 setae. Metathorax with dorsal seta a2 displaced distally relative to seta a1 or mesothorax and metathorax with dorsal central setae in 3 rows. Metathorax with dorsal seta a2 not displaced distally relative to seta a1.

References