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Samuli Siltanen @samulisiltanen.bsky.social · 1d

Ready for Monday Spider? Here we go:

Orb-web weaver of genus Wagneriana from Rio de Janeiro 🇧🇷

Samuli Siltanen @samulisiltanen.bsky.social · 8d

Monday Spider time again!

Quality cobweb weaver from Rio de Janeiro 🇧🇷: Thwaitesia affinis. There’s amazing biodiversity in the city!

#theridiidae #spidermacro

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Samuli Siltanen @samulisiltanen.bsky.social · 15d

Micrathena sp. female spider from Rio de Janeiro. What an amazing thorny shape!

#araneidae #spidermacro #spidersky

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Samuli Siltanen @samulisiltanen.bsky.social · 22d

Spiders of family Pholcidae have specific eye arrangement: clusters of three eyes on the sides, and two eyes in the middle.

Many species, including Carapoia lutea shown here, have really long slender legs. This has earned them the nickname “daddy long legs spiders”.

#pholcidae #spidermacro

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Samuli Siltanen @samulisiltanen.bsky.social · 29d

Free hugs! But beware of spikes.

Female Gelanor zonatus from Brazil. Being a member of family Mimetidae, she hunts other spiders for food.

#spidersky #mimetidae #rio

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Samuli Siltanen @samulisiltanen.bsky.social · Sep 12

Kiertomatriisi ja digikuvien kääntäminen aiheena uudessa matikkavideossani!

Matematiikan ihmeitä: Kiertomatriisi
youtu.be/Wzlzepodcf0

Matematiikan ihmeitä: Kiertomatriisi

YouTube video by Samun tiedekanava

youtu.be

Samuli Siltanen @samulisiltanen.bsky.social · Sep 8

Striped female spider (Leucauge volupis) from Rio de Janeiro.

Amazingly, she manages to wear the colors of Brazilian flag 🇧🇷 AND a tin foil sweater.

#spidermacro #tetragnathidae #spider #spidersky

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Samuli Siltanen @samulisiltanen.bsky.social · Sep 1

Spiders have eight legs and two extra limbs called pedipalps, located in front. Usually the pedipalps are short.

Not so with Gelanor zonatus! This Brazilian male sports palps long enough to win a boxing match against any species with a regular reach.

#mimetidae #spidermacro

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Reposted by Samuli Siltanen

Mikael Niku @mikaelniku.bsky.social · Aug 27

Pitkästä aikaa aamutuimaan turisemassa tieteestä @jukkahakkinen.bsky.social ja @samulisiltanen.bsky.social mainiossa seurassa :) areena.yle.fi/1-75988084

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Samuli Siltanen @samulisiltanen.bsky.social · Aug 25

Noegus sp. jumper from Rio de Janeiro. What captivating eyes! #satlicidae #spidersky #mondayspider

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Samuli Siltanen @samulisiltanen.bsky.social · Aug 18

Araneus unanimus from Rio de Janeiro, Brazil.

The form is identical to the garden spider Araneus diadematus that you can find everywhere in Europe. But the color is straight out of the flag of Brazil! 🇧🇷

#spidermacro #araneidae #spidersky

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Samuli Siltanen @samulisiltanen.bsky.social · Aug 11

Done! 😊

Samuli Siltanen @samulisiltanen.bsky.social · Aug 11

Brazilian dark star: female Gasteracantha cancriformis.
#spidermacro #araneidae

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Samuli Siltanen @samulisiltanen.bsky.social · Aug 11

That I do not know. Probably the difference is not all that drastic as in the families containing the four-eyed species the eyesight is pretty poor even with eight eyes.

Some underground-dwelling spiders have lost all their eyes, which is more straightforward to understand.

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Samuli Siltanen @samulisiltanen.bsky.social · Aug 10

It’s very rare. Out of over 53000 spider species known to science, just about 100 have four eyes. Genera Tetrablemma, Nopsides, Notnops and Miagrammopes are examples; I could not find others.

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Samuli Siltanen @samulisiltanen.bsky.social · Aug 6

Most spiders have 8 eyes. But there are some exceptions, like this slender Miagrammopes sp. sporting 4 eyes! I found it in Rio de Janeiro. #uloboridae

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Samuli Siltanen @samulisiltanen.bsky.social · Jul 28

Crab spider (Tmarus sp.) from the botanical garden of Rio de Janeiro. #spidermacro #spidersky

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Samuli Siltanen @samulisiltanen.bsky.social · Jul 21

Introducing Walckenaeria atrotibialis, a small ground-dwelling spider with orange and black coloration. The back of head is shaped like a saddle, perfect for riding if you were one millimeter tall.

Why “atrotibialis”? Note the black tibia segments in the legs. Atrum is black in Latin.

#spidersky

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Samuli Siltanen @samulisiltanen.bsky.social · Jul 14

Metellina merianae spider belongs to the orb-web weaving family #Tetragnathidae. It lives in caves or other kinds of hollow spaces and requires just the right humidity.

#spidermacro

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Samuli Siltanen @samulisiltanen.bsky.social · Jul 7

Salticus cingulatus, a singularly stunning variety of zebra jumping spiders.

The genus name “Salticus“ comes from the Latin verb “saltare”, meaning both jumping and dancing. So we could actually call them dancing spiders! 🕺

#salticidae #spidermacro #SpiderSky

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Samuli Siltanen @samulisiltanen.bsky.social · Jun 30

Cuteness alert!

Baby Pseudeuophrys erratica, as adorable as they ever come. #salticidae #jumpingspider

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Samuli Siltanen @samulisiltanen.bsky.social · Jun 23

What a green jewel!

Tetragnatha pinicola, literally the “four-jawed pine-dweller“, weaves an orb web with a hole in the middle. As a further distinction from regular, Araneidae-type orb weavers, T. pinicola builds its web not vertically but at an angle.

#tetragnathidae #spidermacro

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Samuli Siltanen @samulisiltanen.bsky.social · Jun 16

Monday Spider. Buongiorno! Greetings from Bologna, Italy. I am here attending a mathematical workshop. As usual, I sample the local arachnids. This jumper lives in Parco della Montagnola. #salticidae #spidermacro

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Samuli Siltanen @samulisiltanen.bsky.social · Jun 9

Monday Spider. Oedothorax gibbosus likes to do things a bit differently. While most dwarf spiders hunt with a sheet web, O. gibbosus runs down its prey.

This handsome male is about 2mm long. #linyphiidae #SpiderSky

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Samuli Siltanen @samulisiltanen.bsky.social · Jun 2

Monday Spider: Tapinocyba insecta, minibeast of boreal forests. This male is less than 2mm in length!

Note the sulci, seen as slits between the lateral eyes. That’s where this gentleman oozes sweet perfume for lady-spoods to love.
#linyphiidae

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