Looking at a spider's belly

 I posted this photo a couple of days ago, and now want to look at it again, closely.

Araneus diadematus

These are beautiful spiders, and I mostly look at the patterns on the top of their abdomen; white patches on orange or brown, these patches arranged to form a cross. Here, she hangs quietly in her web, allowing me to see her underside, and even get it all more or less in focus.

She's a female. First, her pedipalps, the two spiky, curved appendages in front of her fangs, are slim. Mature males have a large "boxing glove" tip to theirs.

And then, near the forward end of her abdomen, she has an appendage called the epigyne. (The cream-coloured, curvy hook crossing the border between yellow and dark brown.) This aids in mating, holding the male's pedipalp in place, and later serves as an ovipositor, the egg-laying organ.

The eight legs are all connected to the front half of the body, the cephalothorax, in a circle around the sternum (in humans this word is used for the breastbone; spiders have no internal bones). They are moved by hydraulic pressure regulated inside the cephalothorax.

At the rear end of the abdomen, you can see her spinnerets. Silk from glands inside her abdomen is squeezed out through these and hardens quickly to form her web.

Our Araneus diadematus has three pairs of spinnerets. Each pair produces threads with specific characteristics. For example, the web’s orbital or circular threads are sticky, good for snaring prey. Others, like the radial threads linking the hub to the periphery of the web, are extra strong but are not sticky. (Nature'sDepths/wondrous-webs)

I found this photo of Araneus diadematus spinnerets, taken with an scanning electron microscope:

From JeremyPoolesem.org.uk

This page also has photos of the epigyne, the pedipalps, and other details of this spider. Go look!

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Subí esta foto el otro dia, pero quiero volver a mirarla con más atención.

Foto: Araneus diadematus

Estas son unas arañas hermosas, y por lo general estoy mirando los diseños en la parte superior del abdomen; manchas blancas sobre un fondo en anaranjado o café, las manchas organizadas en forma de cruz. Aquí en esta foto, se quedaba quieta en su telaraña, mostrándome la parte inferior de su cuerpo.

Es una hembra. Esto se sabe por la forma de sus pedipalpos, esos dos apéndices con espinas, en frente de sus quelíceros; su extremo es delgado; los pedipalpos de arañas machos maduros son inflados; se les ha comparado con los guantes de un boxeador.

Y además, cerca del frente de su abdomen, se ve el apéndice llamado el epigino, que es el ganchito que cruza el borde entre lo amarillo y lo café en la foto. Este apéndice ayuda en la cópula, deteniéndo el órgano del macho, y luego sirve de ovipositor.

Las ocho patas están conectadas a la sección delantera de la araña, el cefalotórax y rodean el esternón. (En humanos, el esternón es el hueso en el centro del pecho. Las arañas no tienen huesos.) Estas patas se mueven a base de presión hidráulica, regulada en el interior del cefalotórax.

En la parte trasera del abdomen, verás las hileras. La telaraña se produce en glándulas dentro del abdomen y el líquido se extruye desde las hileras. Al llegar al exterior, se endurece.

Nuestra Araneus diadematus tiene tres pares de hileras. Cada pareja produce hilos con sus características particulares. Por ejemplo, los hilos orbitales o circulares son pegajosos, sirviendo para atrapar la presa. Otros, como los hilos que unen el centro de la telaraña a su perímetro, son muy fuertes pero no son pegajosos. (de Nature'sDepths/wondrous-webs)

Encontré esta foto de hileras de Araneus diadematus hecha con el microscopio electrónico:

Foto de JeremyPoolesem.org.uk 

Esta página tiene también fotos de los pedipalpos, del epigino y otras partes de la araña. ¡Hay que verlas!

Welcome visitors

 Trying to decide which are my favourite spiders; house and garden edition.

These, I think, are my favourites. Cross spider, Araneus diadematus. Such pretty patterns! And gorgeous webs! In the carport.

No, these are my favourites. Egg case of American house spider, Parasteatoda tepidariorum. Patient parents. Lawn and garden clipping bag.

No, actually, I think these are my favourite spiders.Giant house spider youngster, Tegenaria gigantea. Speedy security guard. On my bedroom wall.

Or maybe it's this one, so fragile-lookiing, so elegant! Cellar spider, Pholcus phalangoides. In a corner of my bedroom, with family everywhere, inside and outside.

But then there are the jumpers, who haven't been visiting lately, but I'm always glad to see them. And the wolves. And the crab spiders. And ...

I give up. They're all wonderful.

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Tratando de decidir cual de todas las arañas que me visitan son mis favoritas. Estas, las de la casa y el jardín.

1. ¿Estas? Araneus diadematus. Porque son tan bonitas, y hacen telarañas muy lindas. Esta está en la cochera.
2. O estas. Parasteatoda tepidariorum. Araña casera americana. Tan pacientes con sus crias. Este es un saco de sus huevos, en la bolsa de desechos del jardín.
3. O no, estas son las favoritas.Tegenaria gigantea. Araña casera gigante. Guardianes de la casa. Este es un jovencito en la pared de mi recámara.
4. No, mejor son estas. Pholcus phalangoides. Una araña fólcida. ¡Tan elegantes, y parecen (pero no son) tan frágiles! Esta espera su presa en una esquina; sus familiares están por todas partes, adentro y afuera.

Pero se me olvidan las saltarines, las cuales no han venido a visitar recientemente, pero siempre son bienvenidas. O las arañas lobo. O las arañas cangrejo. O ...

Me rindo. Me encantan todas.

Diadematus

 And that spider:

I used to find hundreds of these, everywhere; at home, in the bush, in town ... This summer, I've seen none in the bush, and 5 at home. The first four were very small, and didn't last. Nothing to eat, maybe. This one is closer to a normal size. She seems to have chosen a good spot, in the corner, near my recycling bag full of yard waste.

Cross spider, Araneus diadematus, side view.

View with web and shadow.

Three-quarter view. She's keeping her back, with the characteristic cross pattern, against the wall, but her underside is equally distinctive, patterned in orange, brown and black.

I wish her luck.

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Y esa araña:

En años anteriores, encontraba cientos de estas arañas, las arañas de la cruz, Araneus diadematus; sus telarañas se veían alrededor de mi casa, en el centro, en el bosque. Este verano, he visto cinco cerca de mi casa; las primeras cuatro muy pequeñas, y no sobrevivieron; tal vez se les hizo difícil encontrar comida.

Esta es de un tamaño un poco más grande. Parece que ha escogido un buen lugar para situar su telaraña, en una esquina protegida, y cerca de mi depósito de recortes y desechos del jardín. Puede ser que allí encuentre alguna presa.

Tiene la espalda, con su diseño característico de una cruz o corona (según lo miras) contra la pared, pero la parte inferior de su abdomen también es llamativa, con los colores; café, negro, y anaranjado.

Le deseo mucha suerte.

Greedy, part Three (procrastination edition)

I'm still sorting forgotten photos.

First, the backstory: In September of 2018, I was suffering a plague of fruit flies, come to feast on the apples in my yard. A pretty cross spider had set up her web in a doorway, and I was happy to leave her there; she was helping out with the fruit flies. I named her Patience, because she sat there for days without moving.

I posted her photo at the end of August; she had caught one fly, tied it up, and gone for the second, which she hauled back and tied up with the first before she settled down to eat.

A week later, she caught 6 flies and tied them all up in one bundle.

Then I was busy; school had started, and I had time to take her photo again, but no time to process them. They've been sitting on my hard drive ever since.

So here's the next in the series:

Patience, with a humongous, densely packed ball of fruit flies.

She had abandoned her web in the doorway and moved down, closer to the bowl of apples on my table.

Hauling them off to a corner to eat them.

Close-up of her back

She's called a cross spider because of the pattern towards the front (bottom here), but she could also be a pagoda spider by the rest of the art. In Latin, she's Araneus diadematus: a crown spider.

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Sigo revisando fotos olvidadas.

Primero; la historia. Hace año y medio, en septiembre de 2018, sufría de una plaga de moscas de fruta, porque los manzanos alrededor de mi casa estaban llenos de fruta. Una araña bonita "diadematus" se había instalado en una esquina, con mi aprobación porque ayudaba con el control de las moscas. Le puse el nombre de "Paciencia" porque ahí esperaba, dia tras dia, sin moverse.

Al final de Agosto, le saqué unas fotos: había cazado una mosca, la había atado, y luego fue a cazar la segunda, la cual trajo a amarrar con la primera antes de sentarse a comer.

Una semana más tarde, capturó 6 mosquitas, y las amarró todas juntas en una bola.

Después, yo estaba ocupada; había empezado el año escolar, y aunque saqué unas fotos, no tuve tiempo de procesarlas, y allí han estado olvidadas en la computadora hasta ahora.

Bueno, aquí están, for fin:

Había abandonado su red en la esquina, y se mudó más cerca al plato de manzanas en mi mesa. La encontré con una pelota enorme de muchas moscas de fruta.

La última foto muestra el diseño de su abdomen. Se llama, en inglés, una araña de la cruz, por las marcas hacia el frente (parte de abajo de la foto). Pero también se le podría llamar una araña de la pagoda china, por el diseño completo. En Latín, se le llama Araneus diadematus, o sea, araña de la corona.

Swimming school

It was a quiet afternoon down at the wharf. Very few birds. No harbour seals. Even the usual kelp and assorted crabs and sponges on the pilings were in hiding. But there were fish. Tiny ones, from an inch or so to a couple of inches long, hundreds of them, and everywhere I looked.

Most were swimming just under the surface.

Where they broke the surface, nibbling at invisible (to me) goodies, they made rings. And the rings made the fish look stripy.

And just above the surface, a patient cross spider, catching mainly dust. Good thing the fish aren't jumping!

A couple of tubeworms on the underside of a wharf office.

Hundreds of spiderlings

Last October, I found a spider's egg case under the eaves of the outhouse at Oyster Bay. I had a plastic jar in the car, and I trapped it inside, brought it home and stored it outside in a couple of flowerpots to keep it cool, but not likely to freeze. When the weather warmed up a couple of weeks ago, I brought it inside so I could keep an eye on it.

For a few days, I could see the spiderlings inside their case, moving about. Then one morning, they were all out and filling the jar with tiny webs.

Some of the spiderlings, seen through the plastic. The blue at the top is the lid. The pale yellow mass in back is the empty egg case.

The plastic was clear enough to even see the eye arrangement on one of the spiders:

Zooming in. Going by the egg case, the shape, the eye arrangement, and the black triangular patch on their abdomens, these are baby cross spiders, Araneus diadematus.

I took the jar outside and left the lid off. Today, five days later, all the spiderlings have moved on. I'll probably find some, later in the summer, inside my house, eating mosquitoes and fruit flies. They're welcome to them.

Leggy

Two spiders for #Arachtober 23, slightly mis-named:

Cellar spider, not in a cellar.

And a cross spider, never in a cross mood.

Arachtober 15

We're halfway through the month of Arachtober. Todays entries (two per day for the rest of the month) are photos of one who lived for a week in my hallway.

Araneus diadematus male. With spiky legs.

Sleeping "hidden" in a gap behind a shelf.

And now he's gone, probably to sleep in a warm crack for the winter.

#Arachtober

Arachtober 8

Today's spider for Arachtober is the greedy fruit fly chef I wrote about a month ago.

6 fruit flies in one meatball.

#Arachtober

Hungry

Fruit fly season is over. It's cold and rainy; the plums have fallen and rotted away, the late apples are still ripening. And the cross spiders that hung in the centres of their webs in every corner, feasting on red-eyed flies, have given up. Now they wander from ceilings to walls to cracks in the woodwork, hunting. I don't think they're finding much.

"Nothing here, either."

One hangs outside my kitchen window, out of the worst of the rain; her web glistens with tiny bubbles, but there are no struggling dinners. If she hangs in long enough, there may be moths.

#Arachtober

Greedy, Take Two. Or Six.

A week ago I posted the story of a spider and her fruit fly dinner. She had dashed from one end of her web to the other within seconds to catch two flies at once. I wondered then, what would happen if I gave her three flies.

Last night, I took the lid off the fruit fly trap beside her web, and this time a half-dozen flies were caught.

The spider leapt into action, took two steps and stood there, frozen, confused maybe by the signals coming from all sides. She thought about it for a few minutes, then went slowly over to the nearest fly, grabbed it and wrapped it up.

Then she left her dinner hanging, and went for the next, brought it back and wrapped it with the first. Rinse and repeat: she caught all 6 fruit flies and bundled them together before she settled down to eat.

Big meal. The red colouring is fruit fly eyes; 12 of them.

So that question is answered.

In a spring garden with a macro lens

I took my aquarium lens, the one I use to photograph the eyes of my hermit crabs, for a walk around my garden, to see what my old eyes are missing.

Alyssum. 

Apple blossoms. Looks like there'll be a good crop this year.

The holly tree.

I had never noticed the holly flowers before; they're tiny, and the holly sheds sharp-thorned leaves into the grass to puncture my toes, so I've kept my distance. The flowers are almost waxy and each clump has one of those upright sprigs growing from the center.

I'm not sure what this is. I bought the pot full of buds at a garage sale. I like the papery bud wraps.

A bowlful of pink flowers and white crepe paper.

Wild bluebells. And pink bluebells.

The genus is Hyacinthoides, meaning "like hyacinth". Except that they don't have the strong fragrance of hyacinths. These are possibly H. hispanica, the Spanish bluebell.

Araneus diadematus. Not a flower, but a bright point in the garden.

The neutrals

More from my collection of "someday" photos; a sampler of muted greens and browns. Designer colours, for some. Easy on the eye, but maybe too easy if you're trying to find an invisible grasshopper or a lurking spider.

Cross spider, Araneus diadematus, in her web over the water between the docks.

Grasshopper, Oyster Bay.

Lichen, Cladonia sp., Oyster Bay. Almost matches the grasshopper.

This lichen is in a log at Strathcona Lodge, on Upper Campbell Lake. The little scaly (or leafy?) cone-like buds are intriguing. (Click for full size.) I wish I'd seen them at the time. The camera's eye is better than mine.

"Eye" in a log. Strathcona Lodge. I'm pretty sure there's a spider in there.

Dippers on sandstone, Woodhus Creek. They kept running under the water in the calm spots, where the caddisfly larvae were.

Sparrows, Tyee Spit.

When the light is right, even the water is brown. Sandpipers, off Tyee Spit.

Here and there.

Farewell party?

My aquarium critters needed eelgrass. Lots of eelgrass. I'm going to take them, tank and all, on a 5 hour trip, probably bumpy at times, and they'll have to leave most of their water behind. Several gallons of water sloshing back and forth unpredictably can cause quite a bit of damage, so I'll leave them an inch or so, and pack the tank with wet eelgrass. The anemones and snails will hide under the sand, and the hermits will cling to the eelgrass, and all will be well. I hope.

Very tiny hermit, climbing the eelgrass.

Down at Boundary Bay, I found everything all laid out for me; piles of fresh eelgrass, with roots and the diatom fuzz the hermits love, big sheets of sea lettuce, even a fresh holdfast, just the right size for the tank. The wind and tide had been working in my favour; the tide was high and still coming in, and the wind had whipped the waves into a froth. Together, they'd dug up an eelgrass bed from the lower intertidal zone and deposited it, still fresh and barely tangled, at the water line for me.

My hermits are happy.

So were the wind surfers.

I had another item on my shopping list: I wanted photos of spiders for the Arachtober group. So I poked around the fences and alleys of Beach Grove, peering into cracks and under shrubs. (The residents there are very tolerant; mostly they smile. One man told me there were many wolf spiders along his fence. I didn't find any.)

I found, first, a couple of abandoned paper wasp nests.

Look at this (click) full size to see the texture of the paper.

And yes, I found two spiders.

Large cross spider.

These get their name from the cross shape (sort of) on their abdomen. The scientific name is Araneus diadematus, meaning "crown spider", which doesn't sound quite right. I don't see a crown. This one looks more like a Christmas tree, all decorated. The ones here in North Delta are mostly orange and brown; both the Beach Grove spiders were brown and grey.

And then I drove home, saying, "Goodbye, see you later," to all the old favourite landmarks on the way. Next week at this time, I'll be on the Island.

Cruel disappointment

At Reifel Island:

"Supper coming! My fave! Yum!"

"Hey, where'd it go?"

"Life's not fair!"

Time elapsed, elation to despair: 4 seconds.

Hanging in there

A pretty cross spider. She sits in her web between the wall and a post all day, all night, every day. And every time I look closely, she's munching on a tiny fly.

The dark spot underneath her head is the latest meal.