CHILOPODA (centipedes) > GEOPHILOMORPHA (soil centipedes) > Geophilidae

Geophilus osquidatum is a nationally scarce species with very few confirmed records, almost certainly due to its similarity with the common Geophilus flavus, which is why the following photos have been labelled as 'likely' rather than 'definite' as they can only be positively distinguished from subtle microscopic characters.

They are very slender, about forty times longer than broad, with a maximum length of 30mm compared with Geophilus flavus that can grow much longer, up to 45mm. The antennae are noticeably long, about five or six times the breadth of the head and, on average, about one ninth of the body length. The antennal segments are described as very elongate. Both species are yellow in colour with a distinctly darker anterior region.

The all-important trunk segments and leg-pair count is 53-55 for males and 55-63 for females. Whilst there is an overlap with Geophilus flavus the 'key' states the maximum count for that species is 57. Consequently, it's a fair assumption to conclude that any individual, such as the one featured here, that has either 59, 61 or 63 pairs of legs would be Geophilus osquidatum and that was certainly my understanding when I posted the photo and details on the BMIG FB Group. However, despite being accepted as a plausible discovery, it was considered non-conclusive as it is not unknown for an individual to break the rules regarding the number of legs. Personally, I find that statement rather strange given that a survey carried out across NW Europe a little while back discovered that the leg-pair count for species of Geophilus flavus recorded in Britain was actually lower than in other countries, 47-53 for males and 49-55 for females, making the likelihood of a specimen with 61 pairs even more unusual.

Notwithstanding the above comments, Geophilus osquidatum is said to be most abundant in south Wales and the south-west where it may be found in both coastal and inland areas across a wide range of habitats including gardens.