Category: insects and other arthropods

Readers’ wildlife photos

February 15, 2023 • 8:15 am

Thank Ceiling Cat, for readers have responded by sending in several batches of new wildlife photos. Today’s is from regular contributor Mark Sturtevant, who loves his arthropods. Here are photos of some, along with two mushroom photos (click all to enlarge); Mark’s notes are indented:

Here are more pictures of mostly local arthropods from two summers ago. The photographs were taken from area parks where I live in eastern Michigan. Many pictures are manual focus stacks to increase depth of focus.

The spiders shown in the first pictures are different species of sac spiders. These are small wandering spiders. The first is the long-legged sac spider (Cheiracanthium sp.), a common year-long resident in houses. They are a welcome sight on our walls during the long winters here, although I have learned in preparing this that their venom can cause necrotic effects in humans:

The second species is the broad-faced sac spider, Trachelas tranquillus. I don’t see these in houses, but they commonly turn up in bushes near the house. Their bite can also result in complications:

The spiders shown in the next pictures are in the nursery web spider family, so-named because females tend to their hatchlings in a web “nursery” on top of plants. The first is pretty much our largest spider, Dolomedes tenebrosus. You can have a gander at the linked picture to learn that these are indeed spiders of impressive size:

The second species is a smaller kind of nursery web spider called Pisaurina mira. It took a lot of experimentation with camera settings to combine flash and ambient light to preserve the glow of sunlight through the leaf:

The next picture shows a handsome male Pike slender jumping spider Marpissa pikei. I can sometimes get them by using a sweep net in tall grasses. These elongate jumping spiders are a delight to work with because unlike most jumping spiders they are willing to sit still for me so long as they can align themselves on a blade of grass:

The grasshopper nymph shown next was also picked up in a sweep net. This is the northern green-striped grasshopper (Chortophaga viridifasciata) that I posed on my straw hat for pictures:

This is a predatory robber fly. I can’t get the ID on this small one, and that will be the case for some of the other pictures below (sorry!):

Next is a rather strange caterpillar that I also have not been able to identify. It looks like an inchworm, but actually caterpillars from different families also have this look.

The cryptically shaped moth shown next is definitely known to me. This is a common looper moth, Autographa precationis, that turned up at a porch light one evening:

The last pictures are of mushrooms (species unknown), and they were taken with the inexpensive Opteka wide-angle macro lens. I always carry that lens around when I’m out with the cameras in case scenes like these turn up. The pictures are assembled from two or more pictures taken at different flash powers and shutter speeds to either expose for the foreground or the background. The different pictures were then blended together thru layer masks. A thing that is rather strange about wide angle macro lenses is that although it does not look like it, the subjects are less than an inch away from the lens:

Readers’ wildlife photos

February 2, 2023 • 8:15 am

Again I appeal to readers to send in their good wildlife photos. Let’s keep this feature going!

Today’s post features photos by stalwart regular Mark Sturtevant. Mark’s captions and IDs are indented, and you can enlarge the photos by clicking on them.

Here are insect pictures from two summers ago.

I had recently shown the European earwig, Forficula auricularia, and here we go again. The rear pincers are modified cerci appendages that many insects have. Cerci are commonly used as sensory appendages, but earwigs have adapted them for a number of uses that include defense, handling prey (they are omnivores), and males use them for jousting. Toward that end, earwig cerci are dimorphic between the sexes. The first picture is a female, and the next are males. Besides being larger, male cerci come in different sizes and sometimes they are asymmetric. You can see males fighting with their cerci in this video. It also explains why some cerci are a bit lopsided.

There seems to be some debate about name “earwig”. There is the myth that they may crawl into peoples’ ears, but another claim is that the name has to do with their remarkable hind wings that are ear-shaped when unfolded. The unfurling of their wings is pretty impressive, and you can see that in slow motion below:

Next is a picture of a spined assassin bug, Sinea diadema. This is a predatory insect.

I was in the woods one day when I came across this unidentified leaf beetle (Chrysomelidae) in a bush. I was negotiating how to photograph the beetle, but a stink bug nymph suddenly appeared from behind and impaled it! Some stink bugs are predators, and I have seen them with dispatched prey that are much larger and more powerful than they are. One can fairly wonder how such slow insects might be predatory, but I guess it just takes a poke from their proboscis and their victim is secured. The stink bug is Podisus sp.

The beetle dragged the bug behind for several minutes, but the bug grimly hung on. Meanwhile, a bundle of needle-like styli would be scissoring their way into the beetles’ innards, and digestive juices would be injected.

Gradually, the beetle began to slow, and then it was immobilized. A small murder in the woods!

Next up is a two-striped planthopper, Acanalonia bivittata. “Planthoppers” encompass a number of insect families, this one being Fulgoridae. There are also “leafhoppers” and “treehoppers”. One day I should try to memorize what the differences are supposed to be. All of these and other related families were once in their own insect order, the Homoptera (“uniform wing). But now they are awkwardly but I expect correctly absorbed into the order Hemiptera (“half wing”), along with the above stink bug.

Here is a nymph of what is likely the two-spotted tree cricket, Neoxabea bipunctata. This is a young male, and you can see it is developing the specialized front wings that are used by males for chirping, and the larger fan-like hind wings which they fly with. In adults, the hind wings are of course folded up and covered by the front wings. But at this earlier stage the position of the wings are curiously reversed so that the hind wings cover the front wings.

I had found this tiger beetle that was disabled, and so I could pick it up. Tiger beetles are predators that use their good vision and considerable speed to tackle small prey. There is dispute about the taxonomy of this group. They had long been placed in their own beetle family (Cicindelidae), but others have placed them within the ground beetle family (Carabidae). I can say only that there are many ground beetles that resemble tiger beetles, and tiger beetles that look like ground beetles, and whatever side you are on there is agreement they are closely related. Tiger beetle mandibles look pretty imposing, but the bite strength of this small one isn’t detectable. I did not think to get the species.

Next is a large ichneumon wasp, Megarhyssa macrurus, which had apparently recently emerged as an adult and was not quite ready to fly. The extraordinary ovipositor hanging off the rear is considerably longer than its body, and is used to drill into wood to lay an egg in a wood-boring sawfly larva.

Finally, I expect that most people know that scorpions fluoresce under UV light. Actually, UV fluorescence appears here and there among arthropods in general, and plants will also fluoresce under UV. It’s fun to go out at night with an inexpensive LED UV flashlight to see what turns up.  Your own back yard becomes fairly transformed into a semi-alien world. Leaves, flowers, and sometimes arthropods will blaze in day-glo colors.

I had found that aphids also fluorescence under UV light. Here are poplar tree aphids (Chaitophorus populicola), first in regular light, and then under UV light. There are two issues here, though. There is some motion blur from the aphids because the exposure needed to be long. And although the aphid fluorescent color seems pretty accurate, the leaf color is wrong since it is supposed to be deep red under UV. My current flashlight is cheap, and it certainly does not put out only UV light.

Readers’ wildlife photos

January 17, 2023 • 8:15 am

Today’s photos are a batch of microorganisms and small creatures sent in by reader Mary Rasmussen. Her captions and narrative are indented, and you can enlarge the photos by clicking on them.

If there’s water, there’s probably something living in it.

I collected a half gallon of water, muck, detritus, rocks, a tiny aquatic plant and 3 snails from some very shallow temporary pools along the Lake Michigan shore. Lake Michigan’s depth varies year-to-year. The pools sometimes last a few years and sometimes just a few weeks. This year the lake level was down and the pools dried up by the end of summer.

I put the water etc. in a 12 inch square glass aquarium with an L.E.D. light on top. These are the creatures living in the water that I was able to photograph.

The last 2 photos are Seed Shrimp that were living in 2 inches of water that had collected in a truck rut in a gravel road.

Aquatic Sowbugs (order: Isopoda) a freshwater crustacean, lived at the bottom of the tank, feeding on organic matter.

Two Hydra (phylum Cnidaria, class Hydrozoa, genus Hydra) After a month there were many of these predators in the tank. I could watch them for hours.

Hydra don’t show any signs of deteriorating with age, and there is speculation that they may be immortal. (I’m sorry but I can’t identify that creature on the left.)

Hydra with bud. The bud is a clone of the parent and will break free when mature.

A freshwater snail laid a trail of eggs on the aquarium wall. These are close to hatching.

Male Cyclops (Cyclops bicuspidatus), the dominant cyclopoid species in Lake Michigan has a single red eye.

Female Cyclops carrying two egg sacs.

Seed Shrimps (subphylum Crustacea, class Ostracoda) have a hard shell and use their antennae to move through the water. These were barely visible in the water of a truck rut.

I used a Nikon D500 camera with three off-camera flashes. For larger creatures (Sowbug, Hydra) I used a Nikkor 105mm macro lens with extension tubes. For smaller creatures (snail eggs, Cyclops, See Shrimp) I used a Laowa 25mm f/2.8 2.5-5X Ultra Macro lens with extension tubes.

 

Readers’ wildlife photos

January 11, 2023 • 8:15 am

Today’s reader introduces himself and his pictures below. Semyon’s words are indented, and you can click the photos to enlarge them. I believe this is the first Russian contributor we’ve had. Welcome!

My name is Semyon Morozov. I’m sending you my wildlife photos.

These photos were taken in August 2016 in my small homeland, Kurgan Oblast (Russia, the south of the West Siberian Plain). Photo hunting was successful at that time!

Here’s a female wasp spider (Argiope bruennichi). Look at these white things on her web: they are called stabilimenta. Their function is not completely clear. Scientists assumed that these structures stabilized the web, but then other explanations appeared, such as protection from predators or attracting prey.

Eurydema ventralis is a shield bug that feeds on crucifers and some other plants. The bug sits on a leaf of Parthenocissus that has been cut by a leafcutter bee (Megachile sp.).

The yellow-winged darter (Sympetrum flaveolum) is one of the most common dragonflies in this area.

This is an odd caterpillar of the grey dagger (Acronicta psi). It was ready to pupate, so I took it home for observation.

But instead, a fat larva of some parasitoid wasp crawled out of the caterpillar! Then the larva pupated, and after 16 days an imago appeared from the pupa.

And here’s the Roesel’s bush-cricket (Roeseliana roeselii). This individual has a saber-like ovipositor at the end of the abdomen, which indicates that it’s a female.

All these arthropods were dwellers of the garden. Now let’s go beyond it. What are these cupcake-like things on the rotten stump? These are the fruiting bodies (aethalia) of the slime mold (Fuligo septica, I guess). These are not fungi but organisms, the life cycle of which includes both a single-celled amoeba-like stage and a macroscopic one.

In the meadow, I found a wasp spider again. This female caught another predator, a dragonfly (it’s most likely the yellow-winged darter).

There was a pond nearby, next to which I met a caterpillar of the drinker moth (Euthrix potatoria). It’s said that the insect was so named because of the caterpillars’ passion for dew.

I found another caterpillar on the pond shore. It was a larva of the reed dagger (Symira albovenosa = Acronicta albovenosa), a moth that likes reed beds.

And finally, here are exuviae of some dragonfly. These are the remains of an exoskeleton that a larva left after molting.

Readers’ wildlife photos

December 22, 2022 • 8:15 am

It looks as if I’ll be in Chicago over Coynezaa, so do send in your photos, and we’ll see if we can keep this feature going over the holidays.

Today’s batch of photos come from Mark Sturtevant, whose IDs and captions are indented. Click the photos to enlarge them.

First up is a bundle of assassin bug eggs. A very common species of this predatory insect is Zelus luridus, and so that is most likely what will hatch from these eggs:

The European earwig (Forficula auricularia) is commonly seen up on plants, and they can accumulate in considerable numbers. Because they nibble on flowers and leaves, gardenersgenerally view them as pests. However, they also eat small arthropods, including aphids. I like them because they are so weird looking, and their matte finish photographs so nicely. The pinchers on the rear are modified cerci (those being appendages that many insects have). When alarmed, they will curl their abdomen like a scorpion, and they do look pretty fierce that way but it’s all a bluff since they cannot pinch in the slightest. But there are claims that other earwig species can use them as weapons of a sort:

In my younger years, the pink spotted ladybeetle (Coleomegilla maculata) was a common sight, but they are pretty rare where I live now. It was therefore exciting to at last find a pink ladybeetle when I was out “bugging” with the camera, but for some reason this one wasn’t moving. One can see why in the picture. Do you see the small cocoon underneath the beetle? That is the cocoon of a parasitic Braconid wasp! So this beetle was unfortunately parasitized, and its body was being used as a kind of protective shield:

Wolf spiders are most active at night, and then they can be easily found by using a flashlight to spot them through their brilliant eye-shine. So I went out to a remote park one evening to look for wolf spiders. The experience was rather startling, since a walk through the woods at night (which was a bit creepy, to be honest) revealed a veritable milky way of tiny glowing green eyes lighting up the trail. The wolf spiders on the trail were all small, but I had no idea they would be so numerous! After about a mile, the woods opened up to a large field and a full moon. More tiny glowing eyes, but not so many. Then I came across a set of eyes that were much bigger, and behind those was a very big wolf spider! A strikingly colored female. After admiring her, she was respectfully scooted into a bug cage. A bit more searching turned up a male of what was clearly the same species. Fortunately, I had two bug cages, and so in he went. Then it was time to go home with the prizes.

When I could get out again, I returned to the field in the day time with the spiders so that they could be properly photographed and then released. The species is Hogna baltimoriana. The female easily had a leg span of about 3 inches, while the skinny male was much smaller:

Bringing up the rear are male and female jumping spiders (Phidippus clarus) that are in an endearing and committed relationship. The male is in plain view, while the female is seen as a vague outline in her silken retreat. According to BugGuide, females of this species are frequently seen hanging out at the top of plants like this. The male, having found her, is now guarding his “intended” against any rival males. Although disturbed by my presence, he would not leave her side:

Readers’ wildlife photos

October 25, 2022 • 8:00 am

Today’s contribution comes from Tony Eales in Queensland; a mixture of invertebrates, molluscs, and even a fungus. Plenty of cool stuff here!. Tony’s notes and IDs are indented, and you can enlarge the photos by clicking on them:

I was sent to Cairns in tropical North Queensland Australia for work and of course took the opportunity to get out and photograph the amazing invertebrate wildlife.

One of the common orb-weaving spiders is also one of the most spectacular. Gasteracantha fornicata, the Northern Jewel Spider. This was the first species of spider to be scientifically described in Australia in 1775. It was collected by Joseph Banks on Cook’s voyage along eastern Australia in 1770 and later described by Johan Christian Fabricius, student of Linnaeus. As adults they are banded dark black-red with white, but this one is a juvenile and is red and yellow.

Another common invertebrate on the leaves of shrubs in the rainforests around Cairns is the snail Leptopoma perlucidum. I think they have a sweet and somewhat comical face.

On a raised boardwalk in Speewah Conservation Park I was surprised to find this decent sized Lychas sp. Bark Scorpion. I have only ever found them under flaking bark before.

One of my favourite finds was this absolute unit of an ant. It is part of the giant Bull-dog Ant complex and this species is usually given as Myrmecia mjobergi. I’m familiar with the relatives that live in the rainforests further south, but I have never seen one with such long mandibles. As with all these nocturnal giants, I found it to be rather placid and timid and a pleasure to photograph.

But my favourite ant was the trap-jaw ants Odontomachus sp. I’ve found so many false trap-jaws and lookalikes before, and it was great to see the real McCoy. And I was very happy to get this shot of two nest mates greeting one another on a leaf.

Speaking of ants, Green Weaver Ants (Oecophylla smaragdina) were everywhere, hardly a tree didn’t have a nest. As always, I hunted for the Green Ant Mimicking Crab Spider, Amyciaea sp. Apparently, they are not uncommon although hard to distinguish from the ants—but as yet I haven’t seen one.

On the other hand, I did find the much rarer, green ant mimicking theridiid, Propostira sp. These are only officially described from India but various observations at places like iNaturalist show they are more widespread and probably occur in low numbers wherever there are Oecophylla.

First the model.

And this is the spider. Up close the mimicry doesn’t look great but the colour match is near perfect and I thought, at first, I was looking at a dead green ant in a web, until it moved.

I found my first classic tropical forest Cordyceps fungus. This one is a member of the Ophiocordyceps dipterigena species complex. I wonder what the different forms of spikes are for.

The rainforest at night was full of an extraordinary variety of Katydids, most of them nymphs. These spider-katydids, Paraphisis chopardi, however, stood out for their strangeness even amongst this diversity. They are predatory with fearsome forearms for grabbing prey.

 But top of the strange list was this Lace Bug, believed to be Oecharis sp. They only attracted scientific interest in 2020 and remain undescribed as yet. The Lace Bug expert looking into them says they seem to be in the genus Oecharis but look nothing like any known species. I find them charming, like a walking 19th Century glass conservatory.

And finally, a mystery. I’ve exhausted my contacts regarding what this could be. The belief is that it’s some kind of spider egg sac. There appears to be some similarities with “silk henge” from South America which is the egg sac of an as yet unidentified spider.  It’s a beautiful little structure, only around 10mm across.

Readers’ wildlife photos

August 27, 2022 • 8:00 am

Today we have a mixture of animals and astronomy. The readers’ captions and IDs are indented, and you can enlarge the photos by clicking on them.

The first three photos are from reader Terry Platt.

The weather hasn’t been helpful recently, but here are some H-alpha images of other objects in the Cygnus region. The NGC7000 image shows an impressive ‘wall’ of hot hydrogen with dark dust clouds. This region is part of the ‘North America’ nebula, which is a very large area of hydrogen emission to the northeast of the bright star Deneb. The nebula overall is vaguely similar to the shape of the USA and this part is ‘California and New Mexico’. It is about 2590 light years from Earth.

The other two images are of the planetary nebula M27. One is processed to show a ‘visual’ appearance, as the eye might see, while the other is very strongly contrast boosted to show the extensive, but faint, outer extensions. Planetary nebulae are the remnants of Sun-like stars, which have exhausted their hydrogen and blown most of their outer layers into the surrounding space. This process begins with ‘helium flashes’ where the helium rich star detonates helium burning for short periods and blows away its outer layers – this is the source of the faint extensions. As the star ages further, the process becomes more continuous and the core of the star is finally exposed as a very hot, but tiny, ‘white dwarf’ . M27 is at this stage and the white dwarf core can be faintly seen at its centre – the Sun may look something like this in about 10 billion years from now. M27 is about 1350 light years away in the constellation of Vulpecula.

Visual image:

Contrast boosted:

And two arthropods by Tony Eales:

More proof, if needed, that jumping spiders are the cats of the arachnid order. A study was published showing sleeping jumping spiders twitch in their sleep and even show what looks like REM periods associated with these twitches. Spider dreams? [JAC: Photos are Tony’s]

And then only a week later I see a story on consciousness in bees.  Here are some small stingless bees looking at me and presumably wondering if I am sentient: