Category: spiders

Readers’ wildlife photos

November 19, 2024 • 8:15 am

We have two batches left (including today’s), so please send in your wildlife photos.

Today’s photos of archnids come from Dean Graetz of Australia, whose IDs and notes are indented. You can enlarge the photos by clicking on them.

Backyard Spiders

Here in Canberra, we grow Australian native desert flowers in our backyard for their colour and insect attraction.  As a consequence, we also attract an array of spiders interested in trapping any visiting insects.  We find all spiders naturally interesting.  They have a 200-million-year fossil record and are a very successful lifeform with about 36,000 species, of which about 2,900 are found in Australia.  We wish to share them with you, such as this specimen.  Undoubtedly a female, she is intriguingly patterned and laying out a very sparse web.

A much larger example of these Flower or Crab spiders with legs folded ready to seize any visiting insect.  Her back pattern is very similar to that of the spider in the first image.  The ragged covering of hairs or spines make is difficult to immediately separate the spider body from the flower.

Leaf-curling Spiders  (Phonognatha graeffei) select a suitable leaf from the ground and, using silk, curl it to form a protective cylinder, silked shut at the top and open at the bottom.  They then live in this protective cylinder with only their legs showing, feeling for the vibrations of a captured insect.  As much as we try, we have never seen this construction happening live.

A distinct species of Flower-type spider, away from our backyard, industriously repairing her web after trapping and ingesting the innards of a wasp-type insect.  Its desiccated remains will be eventually cut loose and discarded.

A demanding situation to interpret.  Barely visible at the bottom of the cluster is a bee abdomen.  Swarming all over it are very young spiders that are suspiciously similar to the presiding web-owning female.  We did not witness the bee capture or the arrival of the young spiders.  So, which event came first?  Intriguing!

Another puzzling situation.  An unusually large amount of silk was used to wrap the butterfly, whose abdomen shape suggests its contents have not yet been liquified and extracted.  The view is of the spider’s underside where a curious spherical body is visible.  A parasitic tick?

An unknown species resting at the centre of her unfinished web.  The visible haloes of dots surrounding her are the small sticky deposits she has symmetrically spaced to eventually hold the long cross-lengths of silk, the last task of web construction.  Fascinating and thought-provoking.

The next two photos are borrowed and are not of our backyard, though we do occasionally find this famous spider here.  It is a large female Redback spider, guarding her near-perfect spherical egg sacs.  This species (Latrodectus hasselti) is well known in Australian popular culture.  It is seriously venomous, agonisingly painful, but apparently not lethal since the development of an antivenom.  It is well-known because, in rural settings, people have had their buttocks bitten while using an outdoor toilet (aka Outhouse) and they have never forgotten the occasion.

As well as regarded as serious threats to people, Redbacks are widely recognised as tough and effective predators.  Their silk is outstandingly strong, here trapping a struggling lizard, and their silk plus venom has been photographed killing small snakes.  Being tough and very effective are characteristics Australians respect. Consequently, many sporting teams use the name Redback because of their uniform colour and to imply their toughness and effectiveness.

So it is no surprise that when an Australian boot company wants to promote its tough and effective work boots, it uses the brand name Redback.  These boots are really ‘bloody good’ boots.  I have two pairs.

Readers’ wildlife photos

October 7, 2024 • 8:15 am

Regular Mark Sturtevant has stepped up with another batch of arthropod photos today (it includesw one bird). Mark’s captions are indented, and you can enlarge them by clicking on the link. But please send in your photos, as we are nearly out.

Most of the subjects were photographed from area parks near where I live, which is in eastern Michigan. A couple were photographed in staged shots on the trusty dining room table.

First up is a green Assassin Bug, Zelus luridus. These are common, but this one was very moribund and had an abnormally distended abdomen. I can only assume it was either infected or parasitized.

Next are a couple beetles. I have lately become interested in Ladybird Beetles that are not the goddamn super common introduced Asian Ladybird, but other species that are harder to find. But here is a new species for me, the Fourteen-spotted Ladybird Beetle, Propylea quatuordecimpunctata (!):

Next up is a pair of Flower Longhorn Beetles, Typocerus velutinus:

I could not identify the wasp shown in the next picture, but the good folks at BugGuide surprised me by identifying it as a Sawfly, Tenthredo grandis. I did not know that these could be carnivorous, but here it is eating an insect:

A few spiders follow. Here is an unidentified Flower Crab Spider feeding on a Syrphid Fly. I don’t have the pictures that would help me to identify either the spider or the prey:

The next spider I know quite well. This is a Sixspotted Orbweaver, Araniella displicata, which is an interesting little spider that seems to always build a small orb web across the face of a curled leaf:

Another unidentified spider is shown next. This is a recently hatched Jumping Spider, and it was super tiny and very cute! I had to use the super macro lens at about 5x to get the picture:

Many Jumping Spiders live on our shed, and about once or twice a year I find one of their mortal enemies on the shed as well. This very weird insect is a Mantidfly, specifically Say’s Mantidfly, Dicromantispa sayi. Mantidflies are related to Lacewings and Antlions, and their larvae grow as parasites within the egg sacs of spiders. This particular species is known to go after the egg sacs of Jumping Spiders, hence they can turn up on the shed, but they will also make use of other spider hosts as well. Mantidflies are very odd-looking, and their convergent evolution on Praying Mantids is obvious:

And finally, here is a rare-for-me vertebrate. I was visiting a new park, and this impressive Sandhill Crane (Grus canadensis) was clearly expecting that I would feed it:

Readers’ wildlife photos

September 21, 2024 • 8:15 am

Today we have Part One of reader Chris Taylor’s photos from Queensland. His captions are indented, and you can enlarge the photos by clicking on them.

After having been unable to travel for the last five years, I was at last able to get away again, so my partner and I decided to escape the cold of Canberra’s winter and travel up to tropical North Queensland. We had arranged to go out to the Bush Heritage Australia reserve at Yourka again, but before going there we had some time to visit the rainforest near the coast. After flying in to Cairns, we drove up to our first campsite in Mossman.

Above the town, the pristine Mossman River flows through a steep sided gorge.

The rainforest here is said to be the oldest on earth. Many ancient plant families are preserved here, including cycads, ferns and primitive conifers. We had a couple of short walks along the paths into the rainforest.

Our campground was on the banks of the Mossman River. A sign in the site was slightly alarming!

I’m not sure how often the crocodiles get up into the town.

But a few days later we travelled the few kilometres further north to the Daintree River, and there were plenty of crocodiles to be seen. There are two species of crocodile found in Australia, the smaller Freshwater Crocodile, and the larger Saltwater species.

This is a Saltwater Crocodile, Crocodylus porosus:

On the Daintree River, a dominant male will rule a territory of many kilometres of the river, and will keep a harem of females. The male will also tolerate a number of juvenile males until they are three or four years old, at which time they will be driven out of the area. Once fully grown they may return to the river to challenge the resident male for his territory and females.

This is a young male. He was only about 2.5m in length.

This is a female of breeding age. She is regulating her body temperature by entering the water, and gaping her mouth to the wind. There are many blood vessels in the roof of the mouth and this cools the blood going to her brain.

There is some concern in Queensland that climate change is having a big adverse effect on the crocodiles. The sex of the hatchling is determined by the temperature:  less than 32oC produces males, but over 34oC the litter is predominantly female. This warming, together with the effects of the flooding caused by Tropical Cyclone Jasper, has led to no young crocodiles surviving in the Daintree for two years.

We also saw the dominant male of this part of the river, a 5m long, 500kg animal known as Scarface.

He is thought to be at least 70 years old, and carries witness to many fights he has had to retain his kingdom. He has lost most if not all of his teeth, but is still able to feed, often on carrion that is carried down the river.

Lining the river banks are stands of Mangrove trees of different species. Here the mangroves are combining to form an island in the river. There are three different forms that the roots take to enable the tree to live in the brackish water.  All three can be seen in this picture.  Most obvious is the prop or stilt root system, where many roots branch off from the trunk of the tree and spread out to form a strong supporting network.  Then there are some that have Buttress roots flaring out from the trunk. These sometimes bend up above the surface before returning to the mud, and are called knee roots. Lastly there are the roots that stick up pencil-like structures known as pneumatophores. All of these are mechanisms that help the plant to regulate oxygen, salt and water intake and removal, and all help to stabilise the mud around the plant, as well as providing a habitat for fish and invertebrates to breed.

In amongst the mangroves were other creatures. This is a Little Pied Cormorant, Microcarbo melanoleucos, a very common bird around Australia.

Further upstream in one of mangroves was a Scrub Python, Simalia kinghorni:

This is Australia’s largest snake, growing to 5m and 20kg., but it is quite at home in the trees. It was resting in the sun when we first encountered it, but soon began to move around in the tree tops. This one was probably approaching the 3m mark. It was fascinating to see how it was able to span the gaps in the branches.

Back at Daintree we saw this White-Lipped Tree Frog, Litoria infrafrenata. This is the largest tree frog in the world. There are other larger frogs but these are unable to climb:

Back at Mossman, we photographed a Giant Orb Weaving spider, Nephila pilipes. This individual had a span across her legs of about 150mm, and a body of 25mm. Her web was rather more that 1m across!

Also in the campground were a number of Orange-footed Scrub Fowl, Megapodius reinwardt. These birds belong to the Megapodidae, along with the Brush Turkey that I will describe later:

There were also Olive-backed Sunbirds, Cinnyris jugularis, flying around the site. This one is a female emerging from the hanging nest made from woven grasses fibres and bark. It is the female who does most of the work of raising the two eggs laid in the nest:

There was also a spectacular display of Red Jade Vine, Mucuna bennettii. Introduced into Australia, this member of the Legume family is a native of Papua New Guinea:

Returning to Cairns for a night we were able to go for a swim in a nearby rainforest stream at the (crocodile free) Crystal Cascades:

Next morning, while waiting to board the bus to Atherton, we went to a café for breakfast. A cheeky Willie Wagtail, Rhipidura leucophrys, decided to join us in the hope of getting crumbs of food from the table.

Continued in Part 2.

 

Readers’ wildlife photos

September 11, 2024 • 8:15 am

And we’re back, with a batch of insect and spider photos from regular Mark Sturtevant. Mark’s comments are indented, and you can enlarge his photos by clicking on them.

Here are more pictures of arthropods that were taken last summer from eastern Michigan, which is where I live. They include both pictures from the field along with staged shots from the ‘ol dining room table.

First up are two bee- or wasp-mimicking Syrphid flies. The first one is Somula decora and the second is Temnostoma alternans. An issue that Syrphid flies will have when mimicking Hymenopterans is that because they are descended from flies with shortened antennae, they lack the long antennae of their models. The first one tries to fix that with antennae that are placed out on a stalk on the head.

The second one (which is doing a great job looking like a Yellowjacket, btw), instead tends to wave its darked front legs up and down as wasps will do with their antennae. The provided link is worth viewing, as it shows one of these flies using its legs. It really sells it! We often see that mimics not only take on the appearance of their models, but they will also imitate some of their identifying behaviors as well.

Next up is a simple Asian Lady Beetle larva Harmonia axyridis. This predatory larva will graze on aphids and then pupate to later become the ubiquitous Lady Beetle that everyone sees everywhere. In case anyone is wondering, the terms Lady Beetle, Ladybird Beetle, and Ladybug (one word) are all widely used, but it is technically more correct to use a reference that they are beetles (Coleoptera), and not bugs (Hemiptera). I will try to remember that.

It has been many years since I’ve seen the beetle shown in the next picture. This is an Elm Borer, Saperda tridentata. The common name of course tells you something about the biology of this insect.

Let’s wrap up this set with some Jumping Spiders, which belong to the family Salticidae (referring to their habit of jumping, or saltating). I am lucky in that many species from this charming family are commonly seen in and around the house. There quite a few more besides the three shown here.

First up is a male Tan or Familiar Jumping Spider, Platycryptus undatus. These are our largest Salticid, and I can always find a few out on the shed. They are distinctly flatter than many members of this family, and they use that to quickly hide inside crevices on the shed. One has to be fast when trying to catch them.

Next is a female Dimorphic jumping spider, Maevia inclemens. They have this name since males come in two color morphs that look completely different. I showed one here a couple posts back. Jumping spiders are usually fidgety to photograph, but a common trick is to calm them down with a little snack.

Last, here is a female Zebra Jumping Spider, Salticus scenicus. These are one of our smallest Salticids. Males sport very large chelicerae and fangs, and I have not managed to get WEIT-worthy pictures of one since (for me) they are always dialed up to eleven. Save it for next season, I always say. Anyway, the last Zebra picture shows a new post-processing trick where I add Dramatic Lighting by using layer masks to apply darkened gradients above and below. This is to add greater depth to the surroundings and to emphasize the subject.

Readers’ wildlife photos

July 19, 2024 • 8:15 am

Saved by the bell, I have two or three batches of photos left. Today we have arthropod photos from one of our most regular contributors, Mark Sturtevant. Mark’s captions and IDs are indented, and you can enlarge his photos by clicking on them.

Here are more pictures of arthropods from the previous summer. They were taken from the area where I live: in eastern Michigan.

I regularly check out our “sun garden” in the backyard to see what is going on, and there I commonly find small herds of Boxelder Bugs (Boisea trivittata) as shown with this group of nymphs. Boxelder Bugs feed on the developing seeds of various trees, not just Boxelder trees, and their bright colors are a signal that they are chemically protected. The winged adults will seek shelter for the winter, and this will include peoples’ homes, so during the winter they will turn up in the house along with overwintering stink bugs and ladybird beetles. But I don’t mind buggy visitors during the long winters:

Next up is a Caddisfly. Caddisflies are a sister taxon to Lepidoptera, but their larvae are usually aquatic. They can be hard to identify, and so I can suggest only that this is in the genus Banksiola because it sure does look like it. This won’t be the only time that my IDs’are uncertain here:

The next two pictures show Wooly Aphids, aphids that secrete a waxy floof for protection. I have no idea about their identity, although it would help if I remembered their host plant. The colony picture shows nymphs, winged males, and wingless females. It was rather disgusting:

We come next to a kind of beetle that has become a bit of an obsession. This is one of the species of gold Tortoise Beetles, so-named for its lovely metallic gold color. The particular species here is Deloyala guttata.  There is a similar one that I also find that can be pretty much all gold but when even slightly disturbed it rapidly turns a plain orange color so that it resembles a toxic ladybug.  This picture also marks a first attempt to add some digital brush work and other enhancements to the surroundings during post-processing. I commonly see this sort of thing in the hobby, and I would now like to dabble in this trickery from time to time:

Both of our local species of gold Tortoise Beetle feed on the leaves of Morning Glory plants and related species. As lovely as the beetles can be, their larvae and pupae are decidedly the opposite. Next is a picture of one of the pupae, and the larvae are similar. One of course notes the icky mass that is held over the back. That is a repellant collection of their poo and cast skins, and is called a “fecal shield”. If you want to find golden Tortoise Beetles, look on Morning Glories or on related plants like Bindweed. Swiss-cheese holes in the leaves are a sign of the larvae, and there is a fair chance that a sparkly adult or two is hiding under a leaf. But be quick, as the adults are very shy.

Next up is a tiny weevil, which I believe to be Conotrachelus sp. It just sat there, locked in this pose, while did a focus stack:

The wasp shown in the next picture is a parasitic Ichneumon wasp, Therion sp. I don’t know what hosts are used by this one, but I do know that a related species will parasitize caterpillars:

If I have a special treat, I like to put it in last and so here it comes. Besides tortoise beetles, I have lately become very interested in the little cobweb building comb-footed spiders (family Theridiidae), especially because their habits are greater than what I had supposed. Familiar examples of spiders in this family include what we call House Spiders in the U.S., and then there are the Widows. As you all know, these more familiar species favor dark places where they sit and wait to ensnare prey that encounter their tangled-looking cobwebs (although their webs actually have some clever designs to them). But the family is large, and Theridiids don’t all lurk in dark places, nor do they all simply stay in a web to wait for prey to come to them.

See this little spider? Rather pretty, isn’t it? This is the Candy-striped spider (Enoplognatha ovata). The picture is a staged manual focus stack of a spider that had wandered on its own onto our back porch. The “sky” is really a paint swatch. The 2nd picture shows a male in our sun garden:

Well, this little spider is a notable marauder of diurnal (daytime active) insects, and it uses different strategies to hunt prey. Candy-striped spiders make small tangled webs near the tops of plants in gardens and fields, and there they aggressively go after insects that so much as touch their web. More recently, I got to watch one of these spiders, lurking below a flower, attack a much larger bee that happened to be foraging on the flower above. The bee had no chance as the spider steadily thrusted loop after loop of silk up from between the petals of the flower, pinning the bees’ feet down. I have pictures to show later – they are still in the camera.

It doesn’t stop there, though. According to this beautifully done research paper, and summarized further in this article, the spiders become even more pro-active hunters under the cover of night. Diurnal insects often sleep up on plants at night, and that is when the little spiders can venture out and blindly explore the plants around them in order to murder insects in their sleep and eat them. It is through this active hunting that a high percentage of their prey are bees and wasps, and the size of the insect affords them no protection. The research paper has a fabulous picture that made the journal cover that conveys the carnage rather well. Y’all really should zoom in on that journal picture to appreciate the horror of it.

So now I am regularly examining the foliage around plants, looking for small, innocent-looking cobwebs. Just this morning I found another one of these spiders sitting on top of a daisy in the sun garden, eating a Hemipteran –like flower crab spiders do. Last summer and again this summer, I am finding hints that at least a couple other Theridiid species may use similar sneak-outside-of-their-web strategies. In iNaturalist there are quite a few pictures of brightly colored spiders in this family that are just sitting around in the open, without tangled webs. So what are they up to? And here is this little Theridiid (Theridion frondeum) in a park near Detroit. She was tucked away in a leaf, and no web was nearby. So how did this nearly blind spider bring down this big fly? As always, there are more questions:

Readers’ wildlife photos

July 15, 2024 • 8:15 am

Well, this is it: the very last batch of photos.  The Black Dog has arrived and scared the rest away.

But we do have some pictures by reader Kevin Elskin from Arkansas. His captions and IDs are indented, and you can enlarge the photos by clicking on them:

Hope all is well with the readers and that you are having a pleasant summer. Northwest Arkansas has missed some of the most brutal heat so far, but it is early. I am sending along some random photos of plants and animals that hang out at my house.

The first picture shows some kitschy art I created for my garden – a farmhouse and barn. Note the critter in the window. The barn is an homage to all of these barns I used to drive by in Western Pennsylvania.  If one looks closely you will see an American Bumblebee, Bombus pensylvanicus, inspecting a coneflower, which I think is the Echinacea purpurea, eastern purple coneflower. You have  to appreciate Fibonacci when you study a coneflower.

The next photo shows my bumblebee friend of the flower of a mealy sage plant, Salvia farinacea. This plant is a gardener’s delight. I found the plant at random a few years back. It grows and presents beautiful blue and white flowers all year long, then is happy to come back again in the spring. I love perennials.

The next photo is an American Goldfinch, Spinus tristis. This photo makes me a little sad, for when I lived near Pittsburgh I could put out a feeder full of Nyger seed and I would get dozens of these beautiful birds every day. When I put that feeder out in Arkansas, the seeds just rot from neglect. Oh well, the finches do pay a visit to the sage, and they really hit the coneflower seeds in the fall.

One summer night a while back, I was wearing a lamp on my forehead, which has a regular white lamp that shines pretty brightly. I turned the light toward my lawn, and hundreds of little glimmering points of light showed up. At first I thought the dew had settle for the night, but after a moment I realized my truck was absolutely dry. Closer inspection of the “dew” revealed that each little point of light was actually a grass spider, genus Agelenopsis. I tried to photograph the “thousand points of light” in my yard, but I never could really capture how many freaking spiders are in my front yard! So you will have to settle with this one little picture of one little spider:

On to more birds. A common little bird in my neighborhood is the barn swallow, Hirundo rustica. These birds are beneficial insectivores.

I made the mistake of letting the swallows build a nest above my front door last year. They are extremely friendly and not at all afraid of humans, but my god do they make an absolute mess of things. First a photo of the brood:

There were five in the nest but sadly one was lost from the nest prior to learning flight. Here is a photo of the sad fledgling, note the parent watching over and also my cat Rocket considering an early lunch (a very sad story follows…). You can also appreciate the poop creation ability of a nest of swallows (I put down a box to try and catch some of it)

The last bird is the house wren. What a loud-mouthed little bird, but so cute.

They nested in a small ceramic nest box hanging from a shepherd’s crook in my garden. The parent enters with food:

And here is the easiest possible “spot the wren” photo, with the bird among the black-eyed susans and the salvia:

And now the sad story. A few years back, Jerry indulged me and allowed the story of Rocket and JB. Short version of story, when we moved back to Arkansas in 2017 we had just had our last cat put to sleep after he suffered what was probably a debilitating stroke. We just assumed our cat lives were over when in the summer of 2019 a little black and white kitten appeared in our lives. We named him Rocket, and after a couple visits at the vet he adopted a friend named JB. JB was a stray struck by a car, and saved by reconstructive surgery to his right legs. This was all paid for by a donation by JB Hunt Trucking to a local animal charity, hence the name JB. JB and Rocket became fast friends.

Early last April, we noticed Rocket was not interested in eating and was quite inactive. We took him to the vet the next morning, and he was diagnosed with pneumonia. Short story, he passed away before the sun rose the next day. He was weeks away from his 5th birthday.

We were devastated by the loss of our little charmer, but poor JB wandered the house crying inconsolably, looking in all of the little hidey holes where Rocket used to hand out. We were so sad.

Time moves on and we visited our local shelter and found these two sisters:

We gave them the names Misty and Sam (those big white whiskers reminded me of Yosemite Sam!). At first JB was not happy – he chuffed and he hissed and he would have nothing to do with the little usurpers. But time does move on and it heals many wounds. JB slowly came around, and just this week we captured this little scene:

Life is good.

Readers’ wildlife photos

May 4, 2024 • 8:15 am

Mark Sturtevant has answered the call for photos with some lovely pictures of insects and plants. Mark’s notes are indented, and you can enlarge the photos by clicking on them.

We begin with the tail end of a trip to Ohio last summer.

There is a terrific bog at a park there which I shall always visit when “bugging” in that state. I don’t often photograph flowers, but these Showy Lady’s Slipper Orchids Cypripedium reginae were abundant, and they are rather special since this species of Lady’s Slipper is generally rare. Visitors are not allowed to stray off of the boardwalks in the park, so my long lens came in handy here. That rule was frequently broken by others, btw, and it really ticked me off:

Next up is a new species of spider, the Western Lynx Spider (Oxyopes scalaris). Lynx spiders are ambush predators that sit up high on plants. Despite its common name, this species is widespread in the U.S., although it was new to me:

At a prairie location, these Soldier Beetles were abundant on various flowers where they were feeding on pollen. Their bright colors are a warning that they are not palatable. I thought they were two species, but it turns out they are both Margined Leatherwings, Chauliognathus marginatus, a species that comes in different color morphs:

Back we go to my resident state of Michigan. At a park some hours to the south of me, there were these mini-swarms of beetles that were feeding and mating on low shrubbery. Another new species. It turns out they are Clay-colored Leaf Beetles, Anomoea laticlavia, and they have an interesting biology in that their larvae live underground where they are tended by ants:

While on the subject of beetles having sex, here are a pair of Asian Ladybird Beetles (Harmonia axyridis), a species that has a number of other common names. They are an introduced and hugely dominant species of “ladybug”, and I worry that they have displaced some native species:

But now we get into some very special items. Near where I live is a park that has several wetland areas with “fens”, or at least that is what our park service calls them. I am told they also have features for “bogs”, however. The different types of wetlands are based on chemistry and water movement, plus the presence of various indicator plants.

Anyway, I call my favorite one “Sturtevant’s Fen” since its location is well off any trail and no one else goes to it. So it is a great place and it is all mine. One of its best features is that it harbors a healthy population of our smallest dragonfly, called the Elfin Skimmer (Nannothemis bella), is a species that is very fussy about the wetland conditions upon which it depends. Ever since I’ve known of these amazing little dragonflies, I’ve had a vision to photograph them in hand in order to convey how incredibly small they are. Catching them with a net was super easy. First, here is a male. I promise he is not being harmed. Next is the very different looking female. She had recently emerged, and so was not inclined to fly. This picture is one of my favoritest pictures I’ve ever taken! Elfin Skimmers are the 2nd smallest dragonfly in the world, and the smallest is a close relative found in China:

Sturtevant’s Fen also has orchids. The most common are these lovely grass pink orchids (Calopogon tuberosus). I believe this is a bog and not a fen indicator, but they are still very nice. The strange yellow thingies up top are lures that are meant to fool bees into foraging upon them since they look like anthers. The weight of the bee then causes the petal to tip down to the central column below, where sticky pollen sacs await to attach onto the hapless bee. Darwin would have appreciated the contrivances of these orchids: