Another unusual insect: Tenthredo baetica (ssp. dominiquei), with only 118 observations world wide, of which 29 for this particular subspecies. It's a wasp – sort of: a sawfly.
The rear limbs are rather large, and I wonder why. For carrying prey?
Wikipedia points out an interesting reversal: in the Tenthredo genus, the larvae eat plants while the adults prey on other insects. Whereas many typical wasps do the opposite: the adults sip nectar but hunt insects to feed their young. https://en.wikipedia.org/wiki/Tenthredo One wonders then what is this adult doing on a flower, engaging in motion patterns characteristic of foraging on nectar and pollen.
I love our solitary bees. In the late morning hours when it’s still cold they sit at the opening of their tubes, looking out, warming up, trying to find the inner strength to get up and start doing things and I can relate so much.
The honeybee brain hosts over 600,000 neurons, at a density higher than that of mammalian brains:
"Our estimate of total brain cell number for the European honeybee (Apis mellifera;
≈ 6.13 × 10^5, s = 1.28 × 10^5; ...) was lower than the existing estimate from brain sections ≈ 8.5 × 10^5"
"the highest neuron densities have been found in the smallest respective species examined (smoky shrews in mammals; 2.08 × 10^5 neurons mg^−1 [14] and goldcrests in birds; 4.9 × 10^5 neurons mg^−1 [16]). The Hymenoptera in our sample have on average higher cell densities than vertebrates (5.94 × 10^5 cells mg^−1; n = 30 species)."
Ants, on the other hand ...
"ants stand out from bees and wasps as having particularly small brains by measures of mass and cell number."
Regarding nutrient and oxygen flow, would be interesting to compare the brains of a large bee like Xylocopa violacea (violet carpenter bee [1]) with that of a small bat like Craseonycteris thonglongyai (bumblebee bat [2]).
These two species are of about the same size (3-5 cm), yet one is an insect and the other is a mammal. Actually, the bee is larger than the bat! I wonder which one has more neurons.
The bee parasites are out en force. Blood bees, nomad bees, and worst of all, the bee body snatchers: conopid flies. It’s tough to be a busy bee minding your own business…
Some wasps are called 'parasitoids' because they lay their eggs in still-living caterpillars. The eggs develop into larvae that eat the caterpillar from the inside.
But turnabout is fair play. Sometimes, other wasps called 'hyperparasitoids' lay their eggs in the larvae of these parasitoids!
The caterpillars also fight back. Their immune system detects the wasp's eggs, and they will do things like surround the eggs in a layer of tissue that chokes them.
But many parasitoid wasps have a trick to stop this. They deploy viruses that infect the caterpillar and affect its behavior in various ways - for example, slowing its immune response to the implanted eggs.
These viruses can become so deeply symbiotic with the wasps that their genetic code becomes part of the wasp's DNA. So every wasp comes born with the ability to produce these viruses. They're called 'polydnaviruses'.
In fact some wasps are symbiotic with two kinds of virus. One kind, on its own, would quickly kill the caterpillar - not good for the wasp. The other kind keeps the first kind under control.
And I'm immensely simplifying things here. There are over 25,000 species of parasitoid wasps, so there's a huge variety of things that happen, which scientists are just starting to understand! I had fun reading this:
Why such diversity? I think it's just that there are so many plants! So insect larvae like caterpillars naturally tend to feed on them... in turn providing a big food source for parasitoids, and so on.
Given that pretty much all insect species, and beyond into spiders and more, are attacked by parasitoid wasps, and that for most hosts there are both host-specific and generic parasitoid wasp species, it’s been estimated that there are more parasitoid wasps than all other insect species combined. Their usually cryptic larval life stages and often brief adult stages may be behind the severe undercounting.
See:
"Quantifying the unquantifiable: why Hymenoptera, not Coleoptera, is the most speciose animal order", Forbes et al. 2018 https://doi.org/10.1186/s12898-018-0176-x
Cataglyphis lutea (UAE and parts of India) is a desert dwelling ant, the photos of this ant on iNaturalist caught my eye, since, like Leptomyrmex erythrocephalus (the Spider Ant of Australia), this these little ants fold their gasters over their mesonoma.
Very little is known about Cataglyphis lutea, shockingly little. I can't even find a mention of gaster folding in any of the brief descriptions of this ant.
Looking forward to reading it in detail. Thanks for highlighting it – and to top it off, on my favourite ants, Cataglyphis, so beautifully introduced by Whener's book: "Desert Navigator".