Armadillidium tirolense 'Lake Garda' Isopods for Sale

Lake Garda is in this animal's name twice, and only one of those is a trade label. Verhoeff described a pill woodlouse from the lake in 1934 and called it Armadillidium benaci, after Benacus, the Roman name for Garda. That name has since been sunk into his own earlier Armadillidium tirolense of 1901. So the hobby's "Lake Garda" and the scientist's benaci are pointing at exactly the same water.

Where it comes from

Armadillidium tirolense Verhoeff, 1901 is a pre-Alpine endemic of the Lombard and Venetian foothills, centred on the Garda basin and running from Lake Iseo east to the hills above Treviso. Verhoeff's own type localities are the olive plantations and rock clefts at Arco, the slopes below the Rocchetta at Riva and the ruins on the Sirmione peninsula, all on the lake; in 1901 Arco and Riva were Austrian South Tyrol, which is where the name comes from. The old museum lots labelled Tyrol are that same Garda material, and there is no separate Austrian population on record. Riva del Garda and Nago material sits in Frankfurt.

That matters more than it sounds. Because the lake is the type area of the species itself, not only of the sunk name, stock collected there is about as close to topotypical as anything in this hobby ever gets. It is a better provenance story than most locality names in the trade, which are frequently just whichever town was nearest the car park.

Appearance, with a caveat

Dark, close to black, broken up with bright yellow and paler markings, and for once the original description backs the trade up: Verhoeff called the body black to slate-grey-black and the trunk brightly sulphur-yellow spotted, the spots asymmetric and variable but forming three unmistakable rows. The vivid "neon yellow and white" framing circulating in the UK trade is that sulphur yellow under a shop light, and our own blog has previously described the same animal as dark with yellow spotting. Both readings can be true of different individuals in one tub, and pattern in this genus varies far more than shop photographs suggest.

Size is published too: Verhoeff gave 18 to 19mm long and 9.5 to 10mm wide for his series. It is a well-built animal, not a dwarf, and it conglobates cleanly.

Keeping them

The distribution does the work here. The core of the range is the olive belt around the lake, where January averages 4 to 5°C and July the mid-twenties, with records running up into the cooler foothills at Bagolino and Recoaro Terme, so this is an animal that sees frost every winter and warm rather than hot summers. We read that as tolerance of the cooler end, and these should not need supplementary heat in a British house. Take 18 to 24°C as the working band. That is an inference from where it lives and not a published thermal tolerance, and we would rather say so than dress it up. Our article on how cold is too cold for isopods is the wider context.

Everything else is standard practice for the genus. Verhoeff found it in olive plantations, scrub-filled rock clefts and old ruins, well-drained ground rather than damp woodland, so the usual Armadillidium band of 50 to 70 per cent suits it: a moisture gradient, wet at one end and dry across most of the floor, with enough cross-ventilation to keep the surface from going stale. Around 5 to 8cm of substrate, hardwood leaf litter, cork bark for cover, and cuttlebone available permanently. Feed the usual mix with protein included.

It is new enough to this country that there is not much shared keeping experience yet, so if yours behave differently to the above we would like to hear about it. Our other pill woodlice are filed under Armadillidium isopods, and if you want another animal with a real, checkable locality behind it rather than a marketing name, the Corfu and Epirus corcyraeum is the closest thing we keep.

Captive-bred stock, posted on a Monday, Tuesday, Wednesday or Thursday and never later in the week. Each order sits on wet moss in a pot vented through the lid, packed inside doubled card, and reaches you the next working day before one. Expect a few spare animals in the tub, and a live arrival guarantee behind the lot.