A very early season sighting … our earliest, by far. This female would have spent the winter underground, and is now looking for a site to start a new burrow. The patch she is exploring is amid an active nesting aggregation of Rhopalum (Crabroninae), not far from our known Cerceris nesting site.
11 September, 2022
Cerceris antipodes

This female has been been actively nesting for over a month, having mated last Autumn and then overwintering below ground. Her mandibles are looking worn but she will probably continue to nest for many weeks to come.
20 November, 2022
Cerceris antipodes

Until late November, the only wasps in evidence are females. Leaf beetles are their principal prey.
24 November, 2022
Cerceris antipodes

When females return with prey, they usually dive straight into their open burrow. But occasionally one will land, briefly. Perhaps she lost her bearings. Or maybe she needs to adjust her grip. She is ageing, her mandibles clearly worn. And she relies on them to hold the beetle’s antennae. Based on the obvious wear, and the date, she’s either of generation O (i.e. overwintering) or a very early 1st generation female.
2 February, 2023
Cerceris antipodes

Over time, females start to show the ravages of a life spent digging and hunting. The mandibles wear, the teeth and tips becoming blunt. And the wings become ragged as they collect small tears along the trailing edges. This female is probably several months old. She will die before May.
19 February, 2023
Cerceris antipodes

The first males appear in late November, and by March they are common sight around the nesting area.
6 March, 2023
Cerceris antipodes

Males are easily distinguised from females. They have a narrower face and smaller body, overall. The higher number of segments in the antennae (13) and gaster (7) are also definitive.
2 April, 2023
Cerceris antipodes

A brief rest between low, patrolling flights around the nesting area.
2 April, 2023
Cerceris antipodes

The brush of golden hairs on the clypeus (green arrows) is another distinctive feature of males. Indeed, it is an identifying feature of most male Philanthinae – including Cerceris – and is seen in very few other wasps. Some species use the brush in scent marking their territories, but Cerceris antipodes does not appear to mark or defend a territory. They simply maintain a vigil in the nesting area, on the lookout for emerging young females.
2 April, 2023
Cerceris antipodes

A young female, probably yet to mate, and sure to overwinter. The silvery hairs on her face and the pointed mandibles are evidence of her youth … as is the date, and the fact that she was attracting a lot of male attention (see next photo)!
21 April, 2023
Cerceris antipodes

For at least 15 minutes he hung about, waiting for a chance to mate with the young female. She would occasionally poke her head out (see previous photo) but mostly she remained tucked away inside, with just her antennae showing (green arrow).
21 April, 2023
Cerceris antipodes

This is what captured my attention … a pair of bodies jammed into the entrance of the burrow, wriggling and kicking but not breaking free.
23 March, 2023
Cerceris antipodes

Another female lands and shows interest.

The second female was not content to watch from the sidelines.

The second female climbs atop the ‘stuck’ pair, exploring the burrow edge with her antennae.

The male is gripping the first female, but they are not coupled … his terminal abdominal segment is well clear of hers.

Finally, after several minutes at the burrow entrance, the first female disappears. She may have simply been stuck, jammed against the wall by the male. More likely, he was restraining her by gripping her thorax with his legs or mandibles.

He seems reluctant to continue into the now-open burrow, backing out as the second female looks on.

As the male moves aside, the second female quickly heads into the burrow. Successfully. A moment after this photo, she had disappeared into the nest.

There is no longer any sign of the two females, now deep inside the nest. Yet the male remains. He straddles the opening, preening and perhaps recuperating.

This is most unusual! Never before have I seen a male behave this way, poking his head into the unguarded burrow. And a moment later he entered the nest, completely disappearing from view! Perhaps the first time he was dragged in by the female, but this time it was clearly his own initiative.

Within moments of entering the nest, he is back at the entrance.

He sits at the entrance for a few seconds before taking off. I watched on for another 15 minutes, but the action was all over. No sign of the females, and the male resumed his patrolling of the general area … that is, back to normal behaviour.

A female approaches her burrow after a successful hunting trip, carrying a deeply paralysed beetle.
18 March, 2023
Cerceris antipodes

The typical view of an active Cerceris nest … the burrow entrance blocked by the broad head of a female on guard duty.
28 February, 2023
Cerceris antipodes

This female is about to dive into her open burrow. It’s likely she is not on hunting duty today, but rather has simply been visiting flowers for a feed of nectar.
24 November, 2022
Cerceris antipodes

This ant quickly moved away, no doubt deterred by the large mandibles of the wasp on guard duty, blocking the burrow.
24 November, 2022
Cerceris antipodes

Velvet ants (Mutillidae) are ever-present around the nesting ground. The flightless females seek to lay their own eggs onto fully-fed, well-developed wasp larvae. This one made several attempts to enter the nest, from different directions, but the attentive guard remained in place.
28 February, 2023

Satellite flies (Miltogramminae) are recognised parasites of ground-nesting bees and ants, including Cerceris (Evans & Matthews, 1970). Rather than lay eggs, they drop live young into the nest burrow or directly onto prey being carried in by provisioning wasps. The fly larvae then feed on the food cache and pupate within the safety of the Cerceris nest. Apparently there was no guard on duty here, and the female hunkered down over the open burrow to release her larva.
20 November, 2022

Rarely a provisioning female returns to find her burrow collapsed. The cause might be a strong wind, fossicking bird, or passing mammal (but not me … I’m careful where I step). This female spent several minutes trying to reopen her burrow. She eventually gave up, abandoning her prey and flying off to rest on nearby vegetation. It was early in the season and I suspect she was nesting solo. If there had been a nestmate inside, they would have cleared the entryway from within. Another potential advantage of having a guard on duty.
10 November, 2022
Cerceris antipodes