“Let's Make Micrographs!”

I'm a PhD candidate in Sydney. My hobby is peering at plants and stuff through my stereo-microscope. My other hobby is sharing them with you! New photos every Monday and Wednesday.

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Identifying plants in the field requires lots of existing knowledge, so what we often do is collect ‘voucher specimens’ and bring them back to the Institute. Firstly, we can identify the plants on our own time, with a stack of reference books and the internet to help us. Secondly, the vouchers we’ve collected are proof that we’ve been studying the plants that we said we were studying — or they might allow other researchers to re-evaluate our work later if (when!) the genus’s taxonomy changes. I got curious as to what a dried voucher looks like, so here’s a voucher from Acacia longifolia (Fabaceae). It turns out that the anthers are preserved really well, when I expected them to be squished!

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As promised, here is a micrograph of the foot pads of this Pelororhinus sp. (Curculionidae) beetle. They’re two-toed and form hooves, like an ungulate! Amazing. You can also see its crazy mouth parts at left.

Today is a milestone! Well yesterday was, actually, because I got my stereo microscope one year ago yesterday. The first micrograph on this blog is also the first micrograph I had ever taken. I think I’ve come a really long way!

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Brisbane Insects identifies this as a White gum tree weevil, Pelororhinus sp. (Curculionidae). There aren’t many photos of one on the net! They list the normal length as 12 mm but this one must have been a baby because it was tiny, perhaps 5 mm in length. The zoom ratio here is about 150:1 pixels:mm. 

I was instantly taken by the amazing texture of its body, I’ve never seen anything like it! Its feet are also fascinating, and I’ve got a better angle of those for Wednesday. The glob of liquid at right is clear nail polish, which I use to mount insects to a sharpened toothpick (also pictured) for easier manipulation.

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Capsules left over from the dropped florets of a Proteaceae. This arrangement of inflorescences nestled terminally and surrounded by a bed of leaves is pretty common in the Proteaceae family.

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The focus of this micrography blog is Australian plants and insects, so it should come as no suprise that I spend a lot of time discussing the adaptations that our plants have developed to deal with Australia’s harsh (and getting harsher) growing conditions.

This leaf from a plant of the family Proteaceae (the underside, or abaxial surface, is shown here) is typical. The leaf is physically thick, the edges thickened and rolled over, and the surface covered with a mat of hairs. This reduces water loss. The leaf is also tipped with a short, sharp spine. This doesn’t look very intimidating at a magnification of about 100 px:1 mm, but that spine is sharp enough to penetrate skin with almost no pressure. That’s an adaptation against herbivory.

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Fruticose lichen growing from a tip of bark. Blue Mountains NP, Sydney.

I realised late last week that I had forgotten to upload the last two micrographs! Dreadfully sorry; I was preparing my first 40-minute speech ever for the Australian Plants Society, who funded part of my Honours work on the genetic contamination of the Moreton Bay fig (Ficus macrophylla). I couldn’t be more pleased with how the talk went, and that speech also marks the beginning of my PhD. It was a good week!

2015 03 28: Derp! I re-read this post and noticed that I had described this as foliose lichen. It’s actually fruticose. They, umm, sound the same, so I typed foliose while thinking fruticose.

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Scales on the wing of a common moth.

This is the kind of thing that excites me as a scientist. We've seen moth scales that look like bird feathers, moth scales that look like little arrows, and here are some moth scales that look like pixels. I am compelled to look at the scale shape of every moth I see from now on.

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Part of a fallen pollen cone from a bunya pine, Araucaria bidwillii (Araucariaceae). Leftover pollen can be seen inside some of these pockets. Hawkesbury, NSW.

The Bunya pine was an important food source of the native people of this land who roasted them, boiled them, or allowed them to sweeten with age. The seed cones are about as big as pineapples and can fall from heights of several storeys, so mature Bunya pines are sometimes accompanied by signs warning people not to stand underneath them. The tree also looks absolutely bizarre, so there's that.

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A common moth, the left half of its body lit with UV light, and the right half with visible light. The very silvery scales are the most reflective, so their arrangement on the wings must create distinctive patterns for UV-seeing nocturnal animals.

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Mystery movement inside a Callistemon sp. flower spike.

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Here's a story. I found a bunch of these little white tufts on the woody remains of shrubs in a burned area of Blue Mountains National Park. I thought it was a fruticose lichen because it's stringy and segmented, but I had a hell of a time actually identifying it as such. When I asked others, the general consensus was that this is basically woolly aphid poop, a long string of the stuff linked together like sausages to form long, soft strands. Wow.

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Detail of moth wing scales from Asura sp. (Arctiidae). Blue Mountains National Park, Australia.

It's fascinating that the scales on this moth should be shaped like long arrows, whereas the scales from the moth I collected previously were shaped more like bird feathers.

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More of last week's Asura sp. (Arctiidae). Blue Mountains National Park, Australia.

Fantastic compound eyes, rad lowhawk, cool fur shawl. The coiled proboscis is for feeding on liquids.

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A moth, probably Asura sp. (ord. Lepidoptera, fam. Arctiidae). Blue Mountains National Park, Australia.

I collected this guy dead on the ground, and there were two others scattered nearby. The bodies weren't damaged, so I have no idea what killed them. Check out its feathery antenna and rad lowhawk, though! I have two more photos of this insect to show you next week.

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A basket of anthers! Wilted flower collected from Blue Mountains National Park, Australia.

This sample is a few days old and very wilted, and unfortunately we collected too little of the plant to be able to identify it. Tentatively going to say that this might be a small Liliaceae.

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The filaments and anthers of Callistemon citrinus (Myrtaceae). The whole genus is commonly called the bottlebrush; the reason is obvious if you look at the whole flower spike.

Look at those crazy anthers! The style and stigma (of a different floret) are also visible in the lower-left. Also notice the hairs of the leaves; these are called trichomes, and like we've seen in many other Australian plants, these are present as a defense against herbivory and drying-out.

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Gotta have a native Australian plant for Australia Day, so here's a close-up of the individual florets of Grevillea banksii (Proteaceae). These come bunched on racemes, stalks bearing mostly flowers, which you can see in the background on the right, behind the violet style. The beige ends of the petal actually house the anther, and the ovary is inside the base.