Springtail genera/species to know in the

Peter Shaw Introduction

• Entomobryomorpha are “typical” and generally have a well developed furca. If you see some in your garden or pitfall traps without a lens it’s usually this group! • They are further subdivided into those where body segments are about equal length ( = equally cut), and those where abd 3 or 4 is enlarged reflecting large muscles ().

Equal length Unequal length – abd 4 enlarged Genera in the Entomobryidae

• Generally large with ciliated macrochaetae and well developed furca. Some have scales. , etc

• It used to be simple – a very big scaly with ant3 elongated and annulated was Tomocerus, and for me always will be. (6 eyes, oddly). Then someone removed the biggest of all, T. longicornis, to the Pogonognathellus.

6 eyes on The furcula lies in a Tomocerus groove in the abdomen

Tomocerus sp – note long ant. III. In this genus ant3 hardly tapers at all and hs no scales. and vulgaris

Tomocerus minor, <= 4.5mm with an irridescent blue sheen. I found this all over St Helena, presumably introduced by humans.

T. minor was once “tridentifera” due to distinctive tridentate teeth at base of T. vulgaris looks similar, but furca. has simple teeth here. Both lack empodial filament Pogonognathellus longicornis

(<= 6mm, with <=8mm antennae – our largest springail). Note lyre-like curving of antennae, diagnostic of the species. Blow on them in the field!

This species is easily told from Tomocerus by microscopic examination of the foot – the empodium has a long filament. Also antenna 3 tapers and carries micro-scales. Formally the labium has a complex ciliated field (‘bearded jaw’), along with the scarce species P. flavescens).

Pogonognathellus longicornis (next to Megalothorax minimus) Entomobryas

These are hairy but scale-less, often boldly marked, active collembola running around on bark or posts.

E. nivalis E. intermedia E. albocincta – mainly in E. nicoleti canopy E. multifasciata Note the paired spots) - stripy!

Lepidocyrtus

Lepido = scaly, and they are! The scales are so thick on some as to give them an iridescent sheen, a bit like living drops of mercury. They jump well too.

Lepidocyrtus – Lepidocyrtus Lepidocyrtus lanuginosus– very common probably lignorum paradoxus – very common in in litters and (based on rainbow note the canopy on surfaces. patterns on ant1-2 prominent Th2. <=1.5mm. and legs) communities, also litters.

As adults these are easily spotted by the 2 basal antennal segments being doubled, giving the appearance of 6 segments.

Orchesella cinta There are 2 big very common species: Orchesella cinta (= “belted”, white abd2 vs black abd3), and O. villosa (an -like pattern but huge hairs). Another 5 species (?), probably scarce, ID by colour pattern. O. villosa Genera in the Isotomidae

• Generally smaller with smooth macrochaetae [not all] and shorter furca; never any scales. notabilis • Everywhere all the time, all over europe too. Has recently been shown by David Porco to be 4 clades

0.1-2.0 mm long, the giveaway is the square dot of an eyepatch with 4 ocelli. , s. lat. This genus has been split down into Isotoma, , and Parisotoma. They all look pretty similar, and a few of species have the habit of turning up in ridiculously disparate habitats. About 10 other species too. Big Isotomas have ciliated macrochaetae and can be mistaken for entomobryids.

Isotoma viridis (and I. anglicana, and I. caerulea). These 3 are told apart by ridges (1 or 2) on the manubrium and hairs (2 or 3) at the base of the dens. Desoria violacea – no manubrial Collectively ubiquitous. Viridis means ridges, 4 teeth on mucro green, but can also be shades of red/brown/grey.

Isotoma viridis, 3mm

Take a small grey/brown Isotoma, give it clubbed hairs (tenant setae) on its legs and make it a keen tree climber, and you’ve got a Vertagopus! 2 species, both common but only near the ground in low habitats like lichen heath.

Vertagopus arboreus. These have a thick waxy cuticle, that can give good iridescence in the correct lighting.

(Flickr: Andrew Robertson)

Vertagopus cinerea is browner with a shorter furca. Take an Isotoma viridis -like , give it trichobothria on its abdomen and a love of water, and you have . (The mucro looks a bit different too).

trichobothria

Isotomurus maculatus – exceedingly common 4 mucronal teeth Tetracanthella I associate the upland species in this genus with my PhD in Northumberland; Tetracanthella wahlgreni an ice age relic. Blue-black with 4 orange spines on abd 6. Have since collected from pennines and Cairngorms – am always pleased to see them. Other species in moss on walls / trees but always scarce.