Crematogaster missouriensis Species Introduction
Claustral and monogynous. One queen to a tube with a PVA sponge, and no food until the first workers are running. Do not pair queens. Crematogaster minutissima, which carried this ant as a subspecies until 2016, will hold dozens of queens in a nest, but C. missouriensis will not, and pairing them costs you a queen.
A central and southeastern ant, recorded from Indiana and Kansas south through Missouri, Arkansas and Texas to Florida, west into Arizona and New Mexico, and on into Mexico. Workers are monomorphic and yellow-orange, running 2 to 3.5mm, with queens at 4.5 to 6mm, and colonies stay modest, in the hundreds to low thousands. Nests are subterranean and in open ground, not in the leaf litter and acorns its closest relatives use. The remarkable part is when you see them at all: in Kansas and Missouri, workers are active above ground for only a few weeks in late spring and early summer, and are not recorded at any other time of year.
A tiny yellow acrobat ant for a keeper who likes a species nobody has written the book on yet. Colonies stay in the hundreds, workers run 2 to 3.5mm, and the whole thing is quiet by nature. This is an ant you judge by its brood pile and the state of its nest rather than by how busy the outworld looks. What kills them is a nest that dries out. They live underground in the wild and have no answer at all to a formicarium that swings dry between waterings.
Formicarium
Wild nests are subterranean, in open ground. Skip the arboreal and twig-style nests that suit the rest of the genus. A small thin-chambered nest that holds moisture is the right call, sized so the colony fills it rather than rattling around inside. Containment is real work at this size. They climb well and find seams, so keep a fluon barrier current on every open wall and fine mesh over any vent.
Water & Humidity
Humid, and consistently so. These are subterranean ants from open ground, nesting below the layer that dries out, and they have no behavioral answer to a formicarium that swings dry between waterings. Keep most of the nest damp, with the gradient running from wet to merely moist rather than wet to dry. Check it on a schedule rather than by eye.
Recommended to use TrapJaw Labs PVA sponges during founding for improved success rates and more nanitics. Keep the tube damp right through founding rather than letting it run down.
Keep a liquid feeder with water (distilled, purified, or spring) in the foraging area at all times. It is recommended to use the TJL Liquid Feeder for these tiny ants as the mesh prevents accidental drowning. Open drops of water or sugar-water will kill workers at this size.
Carbohydrates
Carbohydrates carry the colony. Acrobat ants work honeydew and whatever else is sweet, and the standard field photograph of this species is a knot of workers feeding on a piece of canned peach. We recommend providing sugar-water (we use our Ant Nectar Mix) and fresh-water liquid feeders in the outworld at all times.
Occasional small honey drop in the outworld is fine. Keep it genuinely small and put it somewhere they can walk off, because a drop that means nothing to a Camponotus is a hazard to a 2mm worker.
Keep the feeder stocked around the clock and check it whenever you check the humidity. A colony this size will not empty one quickly, so the real risk is a feeder going stale rather than running dry.
Protein
Generalist and steady, but the smaller half of the diet next to sugar. They take a wide range of insect protein and their appetite tracks the brood. Keep items small. A 2mm worker cannot do much with a whole mealworm, and an uneaten item sitting in a humid nest becomes a mold problem rather than a meal.
Generalists, accepts a wide range of pre-killed insects. TrapJaw Labs feeds our C. missouriensis colonies with pre-killed D. melanogaster and D. hydei fruit flies and pre-cut mealworms. Cut everything small, as at this worker size most of a whole feeder insect goes to waste.
Two to three times per week. Increase amounts to scale with brood development.
Maintenance
Week 1: One queen to a tube, PVA sponge, dark and undisturbed, and no food. Keep the tube damp. A sponge that runs dry is the quiet way a founding ends, and with a monogynous species there is no second queen to fall back on.
Weeks 5–8: First workers ('nanitics') appear. Put out a stocked sugar feeder straight away and start small protein items two to three times a week. The colony will not look busy. A few workers moving between the nest and the feeder is a healthy small colony of this species, so read the brood pile rather than the outworld.
Months 2+: Growth is steady rather than fast, and colonies settle in the hundreds to low thousands instead of exploding. Move them up when about 75% of the nest space is in use, keeping the new nest small enough to hold humidity. Re-apply the fluon barrier on a schedule as the worker count climbs.
Diapause may be required for this species. Crematogaster missouriensis ranges from central Mexico to about 41.8°N, so what your colony needs depends on where it was collected rather than on the species. Southern stock does not need one and will keep working through the winter. Ants from Missouri, Kansas or the Ohio Valley should get 8–10 weeks from late November at 50–60°F. Remove supplemental heat but keep liquid food and water sources fully-stocked, and do not let the nest dry out while it is cool.
Care Summary
- Humidity is the whole job, keep the nest DAMP and check it on a schedule
- Sugar feeder stocked at all times
- Protein 2–3×/week, cut small
- Gradient 74–84°F, steady rather than hot
- Mesh liquid feeder only, open drops drown 2mm workers
- An empty outworld is normal, judge the colony by its brood