Diptera.info

Posted by Robert Heemskerk on 08-12-2007 23:11

Hi other insektforum,

These Collembola species I found under wood, in a the Amsterdam forest near water.
They were quite large for a Collembola sp., about 6-9mm.
The antenna are hudge.

I think these are Tomocerus longicornis but I am not 100% sure if there are some other similar-looking species?

These two species are different in colour, do they differ in colour by age?

Edited by Robert Heemskerk on 10-12-2007 00:30

Posted by Juergen Peters on 09-12-2007 18:57

Hello!

I think they all are rather worn Pogonognathellus (Tomocerus) longicornis, who have lost parts or most of their silvery scales (and the above one, part of his left antenna). But that's only a layman's opinion.

Posted by Robert Heemskerk on 10-12-2007 22:29

Thanks Jorge and Juergen!

You were both right, TOMOCERIDAE indeed and the first and second picture is: Pogonognathellus longicornis! The species on the third picture is:Pogonognathellus flavescens

I got nice help from Frans Janssens, he wrote the following about these Tomoceridae:

''The difference between Pogonognathellus flavescens and Pogonognathellus longicornis is mainly the length of the antennae:
shorter than body = flavescens
longer than body = longicornis
Make sure to verify that the antennae are complete. The short apical 4th antennal segment should be present to be sure about the length of the antenna.

1st picture = Pogonognathellus longicornis (antenna longer then body)
2nd picture = Pogonognathellus longicornis (antenna broken or not pictured... but second diagnostic character = the long bent terminal macrochaeta on the anal abdominal segment)
3rd picture = Pogonognathellus flavescens (antenna shorter then body (although incomplete...), and anal macrochaeta absent)

The body colour of both species is silvergrey when the scale cover is intact, and yellowish/orangish with damaged or (partly) removed scale cover (as in the pictures).''

Edited by Robert Heemskerk on 10-12-2007 22:32