Ponera pennsylvanica (Pennsylvanian Hunter Ant) Care Sheet

This guide was compiled and written by Hugmaster of the 'Canadian Ant-Keepers' discord server, which can be found here. https://discord.gg/tDP8qQgRzq 

This guide has been posted with the permission of the authors. The original article may be found here. I have also made some edits based on my own observations 

Caresheet – Ponera Pensylvanica

Ponera pennsylvanica is a species of ant that is usually found in mesic forests in the Eastern United States. The species' nests are usually found under rotting logs, in rotting stumps or logs, in acorns, in soil, and in leaf mold.

Author Note: These ants have a reputation for being difficult, that is partly true in the way that raising them like other ants will be a challenge and giving them setups where they can be easily observed will be more difficult than simply dropping them inside the perfect conditions and never looking at them. With enough experience and preparation, there are ways to achieve a middle ground and enjoy Ponera to the maximum, without suffering too much in term of difficulty. This species can get habituated to light when foraging, but bright light will spook them.

Before beginning, please make sure you have at least one springtail colony ready to produce (bonuses if you have flour beetles or fruit flies as well) as they are the go-to food for this species.

Taxonomy

-Familia: Formicidae

--Subfamilia: Ponerinae

---Genus: Ponera

----Species: P.Pennsylvanica

Basic information

Origin: North America, most likely was only limited by food availability and temperature.

Habitat: Prefers dark and humid areas and dislike light, especially sunlight. They will rather nest in a dry area than in a humid location with constant light. High humidity doesn’t seem to be an issue for their cocoons.

Colony form: Very polygynous, they are generally non aggressive and join forced with other Poneras they encounter. 

Colony size: Usually no more than 100 in the wild.

Colony age: About 7 years.

Founding: Semi-Claustral, the queen may keep hunting when workers arrive.

Workers: monomorphic

Nesting sizes: Ponera take little space and a whole nest can fit a small area.

Feeding: Poneras have little in term of social stomach, so a constant source of food or prey is preferable. Feeding them multiple springtails at once to let them hunt them down over a few days is preferable. Otherwise, daily or every other day feedings are best. They will temporarily store extra kills. Poneras will give up food that has dried up or cannot be dragged back to their nest (stuck/too sticky), they do not eat outside of their lair.

Hibernation: 6-10 degrees for 3 or 4 months, hibernation can be skipped if kept warm and well fed.

Reproduction: During august and September.

Movement/behavior: Ponera are solo hunters and rarely team up outside of the nest. They climb badly and will rarely attempt to go up any smooth surface, especially those over 45 degree. They are not very fast, but they are very effective in their hunt for soft bodied arthropods, utilising a semi ambush predator approach. Their nesting area/tube needs some form of substrate to give them good footing, as clean glass is a bother to them and may stress the queen.

 

Appearance/Coloration

Workers: dark maroon body.

Queen: dark maroon body with a slightly lighter gaster.

Males: dark maroon/brown body with a lighter thorax

Size

Workers: about 3.5 to 5mm long

Queen: Up to 6 mm long, can be hard to distinguish from the larger workers at a glance.

Males: 4mm to 5mm long.

Development time

at 25°C

Workers: 4-8 weeks

Egg - Larva: about 10 days.

Larva - Pupa: about 16 days

Pupa - Worker: about 12 days

Full cycle about 38 days, can take up to 2 months, depending on heat, food, humidity.

Antkeeping information

Recommended for beginners: Negative, these ants can be particularly tricky. They are a paradox of: one must not disturb the queen during her founding time (and they dislike light), but she also must be fed regularly. Patience is important in ant keeping and keepers must find ways to give the ants the best conditions while bothering them as little as possible during their founding period. 

A healthy springtail colony is mandatory for this species. This species is not recommended for beginners because they have extra steps required to be able to keep them effectively.

Temperature: 22-30c. Ponera are hardy and will develop based mostly on diet and humidity, giving them about 25c is ideal for speed, but can be raised at room temperature.

Humidity: at least 80%, a notch can be made in cotton to let them nest directly in the humid cotton (+ substrate the ant will use), be careful of flooding.

Nest types: Well soaked soil is preferable, even in a test tube. The nesting area should become solid enough so that the tube can be moved carefully without issue (such as to add springtails). Dirt like substrate is preferable over full sand, although success has been heard off with that as well. Ponera need some substrate to weave cocoon and control humidity.

Formicarium accessories: Optional heat source (heat mat, heating cable or heat lamp), but isn’t entirely necessary. Substrate type: This species doesn’t climb well and any form of substrate or realistic setup in the formicarium is very helpful (a small coating of a mix of sand and dirt can do). They will be contained by glass or plastic, without the need for fluon.

Temper/Behavior

Ponera Pennsylvanica is a slow growing ant with relatively slow workers who examine any available area for prey. They hunt alone and prefer to do so when it is darker, they dislike bright light. They are known to kill when they do not need to and store food ahead of time. They generally ignore preys who are too hard to eat or too dry. Their general method of attack is to locate the prey carefully, ambush it with a bite, then quickly sting it. They shape their nest like a small cave using substrate.

Additional antkeeping information

A blank test tube with cotton is probably one of the worst ideas to start a Ponera colony: The slippery floor will stress her, the light will cause her to panic, and the average humidity will not satiate her.

The nesting area needs to be daArk or at least darker at all time, and very humid. Consider using some dirt in the tube against the cotton, possibly pushing the cotton a little more (careful of flooding) or creating a small notch on one of the sides where the queen can go deeper where it will be more humid. Queens have been seen laying eggs from within the cotton/nest itself this way, without the need of extra substrate.

Alternatively, you could consider pushing the cotton deeper to the point where it will become fully flooded (but not leaking), then adding a good amount of substrate to soak the extra liquids. The queen will nest in this small hill against the cotton (can look under the tube to see the nest and eggs/cocoons). Other ways could be attempted, such as 2 cottons in the middle of the tube (one soaked, the other only vaguely humid) with substrate between them and space for the queen to leave the area to hunt in the tube.

Using the tube vertically with substrate at the bottom  (over the cotton) has also been heard off, but this will limit the visibility of the ants (but make feeding easier).

The rest of tube itself does not ‘need’ substrate but should be made easier to walk on. A small mix of soil and sand, applied carefully with a q-tip at the bottom of the tube would do, creating a small dry sandy trail at the bottom.

 

Springtails are the bread and butter of this species and feeding them is necessary, a small outworld for the tube would be recommended if possible (to limit the chances of escapes), but not necessary (keep in mind the queen may have difficulty climbing). While the springtails will climb to the top of the test tube (or in the outworld) to stay safe and avoid the Poneras, they will inevitably have to go toward the water (and the murderous ants) sooner or later.

Depending on the number of springtails fed at a time, multiple feedings can be accomplished at once. 2 easy ways to add springtails are to tilt the tube up carefully (if it can be done without issue to the ants) and add springtails from a culture with a funnel. The second method requires giving material the springtails will cling to (some cotton, small leaves, dead insects’ shells, etc) and placing these into the tube when the queen is not around). Then removing later when the springtails have left it. In case of escape, lick the tip of your index and pick up the ant carefully that way, she will stick to it. Adding them other ways is also possible but may be tedious. Careful of escapes when adding more springtails. Dead fruit flies or flour beetles larvaes can also be used on occasion, but it is recommended to do so when workers arrive, as they will be ignored if they are not found before they dry up. This can change depending on the specific setup used. Careful about putting substrate or objects in their outworld, they may very well decide to nest in/under it and use the tube as a water source/hunting ground/new outworld instead.

If you aim for a true naturalistic setup, beware that you may seldom see the ants, but consider having springtails around for them to hunt, or other small soft bodied insects.

If all you are looking for is getting a colony to grow well and slow, simply place them in a soil-based springtail culture and…ignore them for months. The colony will grow slowly with good food, but be nearly impossible to see, as these ants are cryptic who likes to keep underground when able. This is a good trick when you want to grow colonies to merge with another Ponera colony later, but do not want to care for them as much. (with some setups, springtails cultures can be ignored for months at a time).

The true difficulty of this species is balancing our need to see them against their will to remain unnoticed.

Diet & Nutrition

Sugars

Ponera Pensylvanica have no need for raw carbohydrates and generally ignore any offered.

Protein

This is all, beside the environment, that a good Ponera colony needs to thrive. Think of them as a primitive kind of ants, they hunt when hungry, only eat meat, and do not have many reserves within. While they may ignore long dead/dry protein source, they will give strong reaction to fresh dead ones and otherwise hunt to their heart’s desire. Adding 10 springtails can easily last 3 days, or more. Connecting them to a springtail colony with substrate runs the risk of them making their nest there instead. A healthy springtail colony to feed them from, is all they need.