Category: arthropods

Readers’ wildlife photos

July 1, 2018 • 8:30 am

I urge you to send me your wildlife photos if they’re good ones.  Please limit each dollop to ten photos if you can, and, as always, include the Latin binomial.

Today’s contribution comes from reader Mark Sturtevant, whose notes are indented. (He also sends his first gif.)

In a recent set of pictures, I had introduced antlion larvae which can be kept as ‘pets’. The business end of one of these little beasties is shown in the first picture. I think the species is Brachynemurus abdominalis.

Antlion larvae of course go through metamorphosis. They form a loose cocoon in the sand, and some of these are shown in the next picture. Sorry about the technical violation on the separation of church and state. I was not thinking that day.

The pupae of antlions are rather interesting. Insect pupae can be categorized in terms of having appendages that are either sealed to their body or held out free. Another area of classification is whether their mandibles are immobile – or not. That is, some insect pupae can bite. This appears to be mainly used to chew their way out of the cocoon before the adult ecloses. There are a few insect orders with biting, or decticous pupae, so we have here a thing that may be considered “weird but not unusual”. The insect order Neuroptera (where antlions belong) is one of the orders with decticous pupae.

An exposed antlion pupa is shown in the next two pictures. It is rather hairy, and it turns out that the slightest touch of a hair would trigger a biting action, as you can see. These things were tetchy!

A small gif:

I am especially fond of dragonflies, and the next pictures show some of my favorite species. First, Eastern amberwings (Peritemis tenera) are one of our smallest dragonflies, and here is a male.

Next are larger dragonflies called Eastern pondhawks (Erythemis simplicicollis). Females are green, and males start out that color as well but they develop a lovely blue color as they mature.

This male had not quite completed the transformation.

In the final picture is an orchard orbweaver spider (Leucauge venusta). These beautiful spiders like to build their web in shady places, so photographing them in low light is a bit challenging. This is because the preferred camera settings usually result in a dark background, even when a flash is used, and so the black markings on the spider tend to become lost. I had experimented with setting up a piece of cloth behind one in an attempt to give a brighter but still naturalistic background. The colors turned out to be decidedly unnatural, which was not in the plan, but they seem to ‘go’ with the colors of this spider. I like how the abdomens of these spiders look like antique porcelain.

Readers’ wildlife photos

June 22, 2018 • 8:00 am

Time to gather together your wildlife photos and send them in! The photo tank is dropping, though I still have a reserve.

Tony Eales from Australia sent some creepy-crawlies, because of course everything in Australia is venomous. But these animals are also lovely. His notes are indented:

Went back up into the rainforest last weekend to a different section of the national park to find some more creepy crawlies to photograph.

I managed to find and photograph my first Mygalomorphs. This is the infraorder of spiders that includes tarantulas and the deadly Sydney Funnel-web [JAC: the Funnel-web is regarded as the world’s deadliest spider]. The ones I found are in the family Dipluridae aka the Curtain Web Spiders. The second photo was positively identified as Australothele jamiesoni by Robert Raven who was the researcher to first describe the genus and the seven species in it. The second photo looks similar and photographed very close by, it’s probably A. jamiesoni as well but I can’t be certain. The two long spinnerets that can be seen in the photos are characteristic of the family. The spiders look scary but they’re not large: only around 20mm long.

In addition to spiders I found a couple of scorpions. Homurus waigiensis the Rainforest Scorpion, although I have found them outside of rainforests in swampy open forest. And an unidentified member of the Lychas spinatus species complex.

Lastly a Water Spider, in the family Pisauridae. Robert Raven said it looks like a Megadolomedes trux juvenile but has an unusual pattern. I have seen full-grown M. trux years ago and they are an impressive sight. While having relatively small narrow bodies their span can be as large as a man’s spread hand. They hang out on the underside of rocks above rainforest streams and can eat fish, tadpoles and even small frogs and toads.

 

 

Readers’ wildlife photos

June 7, 2018 • 8:00 am

Reader Tony Eales from Queensland sent some really nice arthropodos photos and descriptions of the subjects (indented). Now that I’ve learned how to embiggen the photos (WordPress changed its schema), you can click on any of these to enlarge it.

I recently spent a morning looking for photographic subjects in a place near to my home in Brisbane called Mt Glorious. There’s an area of montane subtropical rainforest there, and I got some interesting insects and arachnids.

First is a new (for me) species of Arkys, Arkys dilatatus. These spiders were recently split from the orb-weavers into their own family and I love finding new ones. Some are very spectacular and brightly coloured and some like this are tiny and cryptic. This one was only around 3-4mm and when folded up, looking like nothing more than a piece of dirt or bird poo on a leaf.

I found a female ‘trilobite cockroach’ from the Australian (and PNG) family Blaberidae. It’s a female as the males have wings. They live under pieces of bark on eucalyptus trees.

Next is a “Flat Bug” from the family Aradidae. When I put it up on Facebook it generated some interest from one of the Hemipteran experts. Apparently the last record of this species Brachyrhynchus sulcatus in Mt Glorious was in the 60s and there were two other records in the Southeast of my state in the 70s and 80s, but most records are from the far tropical north and PNG with quite a large gap in between.

The small ant Meranoplus sp. They are quite common in the hilly wet forests but I love the look of their golden abdomen and weird shield-like thorax.

I found this tiny Mirid Bug under a leaf. It’s only about 5mm long. The expert I was corresponding with on Facebook says it’s a new species and new genus…so no clue what it is.

Another exclusively Sahulian (Australia and PNG) family, Nicodamidae, the Red and Black Spiders. They are difficult to get to species from photographs but they are all pretty striking. They tend to hunt through the leaf litter which is where I found this one.

The largest Pseudoscorpion I’ve found so far, still only about 6mm. It was sitting on top of a road guardrail, probably looking for something winged to hitch a ride on. This behaviour is common in Pseudoscorpions and is called phoresy.

Another Sahulian family of spiders with some genera in other Gondwanan continents, the flat spiders Trochanteriidae. These live under bark and rocks, some species seem preternaturally thin. This group is in serious need of revision with some near identical spiders placed in the Gnaphosidae.

Crafty crabs cop cans for cribs

June 5, 2018 • 1:30 pm

I have a sore throat (and probably am getting a cold), so I’m going home to rest. I’ll leave you with this video for today. Don’t worry: ducks will be fed, but the Daily Duck Doings will be postponed till tomorrow.

As you probably know, as hermit crabs grow they have to leave their old shells and move into bigger ones. From BBC Earth, we have this lovely video showing hermit crabs, deprived of empty shells, using beverage cans as new homes. The cans aren’t ideal given the asymmetry of the crab, but kindly rangers leave empty shells for the growing beasts.

Readers’ wildlife photos

May 28, 2018 • 7:45 am

I have both domestic and foreign wildlife photos from reader Joe Dickinson, but let’s look at some pictures from his recent trip to Australia and New Zealand. His notes are indented.

Here is a first installment from my recent trip to Australia and New Zealand.  One of the most remarkable wildlife sightings I’ve ever experienced was in Cairns, our first stop.  Right in the heart of the city there are many city blocks lined with trees in which roost fruit bats (the spectacled flying fox, Pteropus conspicullatus) numbering in the thousands—maybe tens of thousands.  The first shot shows part of one tree.  Now extrapolate to six or eight such trees on each side of a block and perhaps 15-20 similar blocks .  Simply amazing.

Most of the bats take flight at dusk.  The camera I am willing to lug halfway around the world does not have a lens fast enough to “freeze” bats in flight in that light, but these shots at least capture some of the feel.

The mountains around Cairns support a lush rainforest in which golden orb spiders are very common (probably genus Nephila but I don’t know the species).

Cairns also was our base for a day trip out on a tiny island that is part off the Great Barrier Reef from which we could snorkel off a beach.   Most impressive there were the giant clams (Tridacna gigas).  This one is at least a meter in diameter.

The colors in the mantle are wonderful and highly variable.  This actually may be another species, the “small” giant clam (T. maxima).

And this is a much smaller species, the burrowing clam (T. crocea).  I think this is the species that I took to be T. gigas when I snorkeled in French Polynesia.

Speaking of Polynesia,  we had the feeling that we saw there a greater diversity of colorful reef fish than we did at this Australian site.  Nevertheless, here is one of the prettiest ones.  I have not been able to identify it despite looking at many pages of on line photos of Australian reef fish.  Perhaps one of your Aussie readers can help.

The little island from which we snorkeled is primarily a bird refuge.  The most abundant birds were the greater crested tern (Sterna bergii) and black noddy (Anous minutus).  It is a nesting colony and, although we could not see any nests, many of the terns at least clearly are juveniles (mottled plumage).

Here is a closer look at a noddy, perched on the rope that formed a boundary to keep us from encroaching on the birds’ part of the island.

This is a juvenile brown booby (Sula leucogaster). We did see adults, which allowed me to identify the species, but I did not get any worthwhile shots of them.

World’s oldest known spider dies at 43; scientists disconsolate

April 29, 2018 • 12:15 pm

This headline tells you how many of us feel about our research subjects (see also here):

The spider, a trapdoor spider (Gaius villosus), was not a coddled lab animal, but a real arachnid in the wild—in western Australia. Affectionately known as “Number 16”, she had been studied since 1974, presumably as a toddler, and was recently found dead. Her longevity beats the previous record—that of a Mexican tarantula—by a full 15 years. And the senior author of the study (see below) is of a venerable age herself.

From the Torygraph (my emphasis):

The arachnid is believed to have survived for so long by sticking to one protected burrow its entire life and expending the minimum of energy.

. . . Published the Pacific Conservation Biology Journal, the research is the life’s work of Barbara York Main, now 88, who first set eyes on Number 16 shortly after its birth.

. . . While trapdoor spiders are poisonous, it is the males, who leave their burrows to find a mate, which are usually encountered by humans.

A typical danger in Australia is homeowners finding what they believe to be dead spiders in their swimming pools, which can then rear up and attack when removed.

The trapdoor species typically take five to seven years to mature and will then invest their energies in a single burrow, with the females rarely venturing more than a few metres away from their place of birth.

Ms Mason said of the Number 16’s death: “We’re really miserable about it.

“We were hoping she could have made it to 50 years old.”

As far as I know (I used to keep tarantulas), females generally live longer than males, and not just because some of the males get nommed after mating.

The Curtin University publicity release is more science-y:

Lead author PhD student Leanda Mason from the School of Molecular and Life Sciences at Curtin University said the ongoing research has led to new discoveries about the longevity of the trapdoor spider.

“To our knowledge this is the oldest spider ever recorded, and her significant life has allowed us to further investigate the trapdoor spider’s behaviour and population dynamics,” Ms Mason said.

“The research project was first initiated by Barbara York Main in 1974, who monitored the long-term spider population for over 42 years in the Central Wheatbelt region of Western Australia.

Here’s the paper’s abstract from the Pacific Conservation Biology Journal (click on screenshot). Our library doesn’t carry this, journal and you’ll have to pay $25 (U.S.) to see the article, but I think you have the relevant data:

Readers’ wildlife (and astronomy) photos

April 19, 2018 • 7:45 am

I’m in Las Cruces, New Mexico, staying with old friends, and I have had, beside convivial conversation, a fajita fix and a cat fix (there are two: one is a calico and the other a feisty tuxedo tom). Photos later.

I see from a very brief scan of the news that talks with North Korea actually look propitious, that Trump is getting ever deeper into trouble (I still predict he won’t last his first term) and two German rappers with anti-Semitic lyrics in their songs won the country’s hip hop music award, something that would never stand in the U.S. So it goes.

I take off today for six days on the road, with a few goals in mind but nothing fixed.  All this is to say that posting will be VERY light, at least by me, until the 25th, when I return here for two days before flying back to Chicago. The Professor Ceiling Cat (Emeritus) abides. But I have a few minutes today to do a readers’ photo post.

Today we feature Aussie posters, the first being Tony Eales from Brisbane. As usual, readers’ notes and IDs are indented:

I recently went on a work trip to outback Queensland to a town called Winton. In my spare time I went looking for interesting local  wildlife to photograph. My prize find was a large wolf spider (Lycosidae). Volker Framenau is working on revising the Australian Lycosids when he can get funds. The family is apparently a mess with many misplaced at the genus level. He said it could be Hoggicosa sp or possibly an undescribed Portacosa sp. which is a new genus first described last year.

From reader Tim Anderson, who sent wildlife and planetary photos:

While being taken for a walk by Paddy the Magnificent Hound, I came upon a family of Black Kites (Milvus migrans). These raptors are very common all over eastern Australia. In some places they are so common that they displace the Australian Raven as the general scavenger.

And Jupiter:

This is an image of Jupiter taken on a very hazy night in Cowra, NSW. The atmosphere hereabouts is currently full of dust and smoke because local farmers are burning off the stubble to get ready for the next wheat crop.
I imaged the planet with a 9.25″ Schmidt-Cassegrain telescope and an ASI224MC camera on an Skywatcher EQ8 mount. The image was captured as a video file, then decomposed to 182 still frames, then stacked with Autostakkert!, processed with Registax using the “wavelet method” (don’t ask me how that works, I just press the buttons), and finally colour adjusted with Photoshop.