CHILOPODA (centipedes) > LITHOBIOMORPHA (stone centipedes) > Lithobiidae

Whilst the previous 'species account' for Lithobius variegatus included a couple of photos of an immature, post-larval stadia that could be identified, most Lithobiids will not be distinguishable until they're fully developed.

The photos below show two individuals that I happened to find in close proximity to each other. The first has 15 pairs of legs, but is obviously a pale immature, so must be a post-larval stadium. Even so, you can clearly see all the trunk segments that were described in the introductory write-up for the Lithobiomorph species, which is worth repeating here to compare against this particular photo.

The fifteen segments consist of mainly alternate large and short tergites along the back. The first large segment behind the head is T1 then T3 and T5, separated by slim segments T2 and T4. The roughly central large T5 segment is then followed by another slim segment T6, before two further large segments T7 and T8 that are together, then two more large segments T10 and T12 separated again by two smaller ones, T9 and T11, and then at the rear T13 and T14. The posterior angles of T7, T9, T11 and T13 may be rounded or angled or may project. I assume that the short forcipular segment directly behind the head in front of T1 makes up the total of fifteen.  

The second photo is interesting as it shows an individual with just ten pairs of legs and, consequently, eleven rather than fifteen trunk segments. I'm not quite sure where this puts it in the development stage as I was told that in all Lithobius species, the first larval stadium has 7 leg pairs, the second 8 pairs and the third 12 pairs, so I guess it must be somewhere between the second and third stadia. The next stage when they have grown the full number of 15 pairs is known as the first post-larval stadium. There are then three further post-larval stadia before they become adults.