Arachnews: February 3, 2020

A week’s worth of arachnid-related art, news, and scientific research.

Neville Park
Feb 5 · 12 min read

An unusually eventful week in arachnology, as paper retractions cast doubt on a prominent expert on social spiders. This edition also includes Sydney funnel-web season; jumping spiders in eyeliner; spiders that live among fire ants; the secret lives of mites that live on dung beetles; and more.

Terms in bold are defined in the Glossary at the end of the post.

Art & Social Media

“A long-jawed orbweaver demonstrates how spiders suspend themselves and climb across single strands of silk…” Sebastian Alejandro Echeverri, Twitter
Three-horned comb-footed spider (Molione cf. triacantha), Goa • Prasanna Parab
Ladies, if he doesn’t sacrifice his legs to pacify you, etc. The paper is Neuman & Schneider 2019, by the way.
  • There’s a lot going on here. A male flower crab spider is mating with a female while she is eating a bee, which is surrounded by flies hoping to steal a bite. Also some of the flies are mating.

Education & Outreach

  • This documentary about Uruguay arachnids is from 2013, but was only uploaded to YouTube in January. It’s got fantastic footage of spider and scorpion behaviour, and at the end there is a nice bit with the featured scientists talking about what drew them to arachnids. In Spanish, with English subtitles. [YouTube]
  • Vena Kapoor and Priya Venkatesh are hoping to raise funding for a set of educational flashcards on the spiders and insects of Bangalore, India. [Twitter]

Events & News


So a couple weeks ago I mentioned that an American Naturalist paper on social spiders was retracted when lead author Kate Laskowski found irregularities in the data collected by the last author, Jonathan Pruitt. It turns out it was just the tip of the iceberg; an earlier related paper in PRSB which they co-authored has been retracted, and another in Biology Letters will likely be soon. Here is a round-up of articles and discussions so far:

  • Kate Laskowski describes the issues that led to her pushing to retract three papers. [Laskowski Lab]
  • Retraction Watch covers it, with comments from American Naturalist editor Dan Bolnick. [Retraction Watch]
  • Several researchers who have worked with Pruitt issue a statement. “We have all been engaged in a close examination of every piece of data we’ve ever been handed by Jonathan Pruitt…We would like to assure the scientific community that we are committed to setting the scientific record straight.” [Ambika Kamath]
  • Behavioural ecologist Raphaël Royauté announces he is making public the data and code from a paper he and Pruitt co-authored, for the sake of transparency. [Twitter, Github]
  • Dan Bolnick shares a Google spreadsheet where people are documenting the status of Pruitt’s publications—which are retracted, dubious, or verified. [Eco-Evo Evo-Eco, Google Sheets]
  • Dan Bolnick also discusses the events at length from his perspective as American Naturalist editor; this is one of the most thorough recaps and analyses so far. [Eco-Evo Evo-Eco]
  • Jeremy Fox, who investigated some of the data irregularities at Bolnick’s request, weighs in. “For those of you who are wondering how so many data irregularities could possibly have gone unnoticed for so long, allow me to confirm from personal experience what others have already said: most of these irregularities are only easy to spot once you know what to look for…None of Pruitt’s collaborators deserve any blame for not noticing these irregularities sooner.” [Dynamic Ecology]
  • Elizabeth Pennisi covers the story for Science Magazine, including new comments from behavioural ecologists and also, for the first time, from Pruitt, who is off doing fieldwork at the moment; he denies allegations of fabricating data. [Science]

TL;DR: without speculating on motive, it can be said that much of Pruitt’s data is faulty and cannot be used. Researchers are emphasizing the need for empathy, professionalism, and transparency. There are many conversations going on about how to improve data practices going forward. Expect more on this story to come.



Putting Makeup On Jumping Spiders

Yes, This Deserves Its Own Category; Please Help Me Expand It

Evarcha culicivora, with and without eyeliner • Cross, Jackson & Taylor 2020
  • Hi guys! It’s me, Evarcha culicivora, back with another product review! In this video I’m going to be trying out a “holy grail” eyeliner, Urban Decay’s liquid eyeliner in blackest-black “Perversion”. I’ve heard good things about the coverage, but can it really mask my beautiful, blood-filled-mosquito-red face? I got some surprising results, so watch till the very end. Remember to like and subscribe! [Paper 🔓️]


A southern big-eared mouse (Loxodontomys micropus) with small orange chigger mites on its ear • Acosta-Jamett G, Martínez-Valdebenito C, Beltrami E, Silva-de La Fuente MC, Jiang J, Richards AL et al. 2020
  • Scrub typhus is a disease caused by the bacteria Orientia tsutsugamushi, spread from rodents to humans via chigger mites. It’s normally found in Asia, but has popped up in a few other places around the world, such as Chiloé Island in southern Chile. To find the vector of the disease, researchers captured rodents, catalogued the mites they found on them, and tested them for O. tsutsugamushi. [Paper 🔓️]
  • Could the northward-moving lone star tick (Amblyomma americanum) pass on Rickettsia rickettsii, the bacteria that causes Rocky Mountain spotted fever, to humans in New Jersey? Probably not — only one tick out of 1,858 collected tested positive for it. But 25% of them did carry the related Rickettsia amblyommatis. It isn’t confirmed to cause any illness in humans, but maybe it could be behind some positive results of tests for rickettsial diseases. [Paper] [Sci‑Hub]
  • This study represents the first reports of ticks on humans in Lebanon. Congratulations, Lebanon! Welcome to the club. Researchers identified an ornate sheep tick (Dermacentor marginalis), a red sheep tick (Haemaphysalis punctata), and a Mediterranean ear tick (Haemaphysalis parva), this last one ironically found on a man’s hand. [Paper 🔓️]
  • How are ticks affected by the pathogens they carry? A new study compares one specific aspect, the chemical composition and structure of the exoskeleton, of ticks infected with the disease-causing bacteria Anaplasma phagocytophilum. [Paper 🔓️]
  • Lots of ticks were found on mammals (rodents and marsupials) from the Amazon in Brazil! The disease-causing Rickettsia amblyommatis was found in all of the tick species they identified, but none of the mammals tested positive for rickettsial infection. [Paper]


  • After the pesticide endosulfan was phased out in Canada in 2016, the cyclamen mite (Phytonemus pallidus) has become a more important strawberry pest. One possible means of control is the predatory mite Neoseiulus cucumeris, but it can’t weather Canada’s cold autumns. [Paper]
  • Even pesticides that are supposedly better at targeting only spider mites have effects on predatory mites. And some pesticides (cough cough, bifenthrin) are not very effective against spider mites, but lethal to their predators! [Paper] [Sci‑Hub]
  • Oils might be a more environmentally-friendly way of controlling the coconut mite (Aceria guerreronis), a pest of — you guessed it — coconuts in Brazil. But how do they affect the activity of the predatory mite Neoseiulus baraki, which also feeds on A. guerreronis? A study compares cottonseed and degummed soybean oil to see how they affect the mites’ appetites. [Paper] [Sci‑Hub]
  • A study of Varroa destructor mites from Japanese commercial apiaries confirms that nearly all of them belong to haplogroup K, a particularly infectious variety that is displacing other V. destructor types. [Paper] [Sci‑Hub]
  • The avocado brown mite (Oligonychus punicae) has a lot of “potential for development” on eucalyptus in clonal minigardens, which is not apparently as positive as it sounds. [Paper]
  • Lots of ticks were found on mammals (rodents and marsupials) from the Amazon in Brazil! The disease-causing Rickettsia amblyommatis was found in all of the tick species they identified, but none of the mammals tested positive for rickettsial infection. [Paper] sounds. [Paper]
  • Neoseiulus californicus can eat a little cattail (Typha angustifolia) pollen, as a treat. [Paper]


Walking and aerial distances between “canopy islands” of epiphytes in a tree • Méndez-Castro, Mendieta-Leiva, Rao & Bader 2020
  • The bigger an island is, the more biodiverse it is. A related idea is that the more isolated an island is, the less biodiverse it is. But “isolation” is relative! When it comes to spiders, some stay in one spot all their lives; others roam around and even use silk to fly or cross long distances. A new paper looks at epiphytic plants as tiny islands and the trees they grow on — shade trees on a Mexican coffee plantation — as archipelagos. By grouping spiders according to mobility, can we better explain island effects? The answer is a definitive sort of. [Paper 🔓️]
  • Peaty Polish rivers make poor environments for water mites, but a few rare species are found there. [Paper 🔓️]
  • Unsurprisingly, networks of predatory mites and the plants they live on are smaller and less rich in Brazil’s savannas and restingas (coastal sandbank forests) than in less dry biomes. [Paper 🔓️]
  • A recent Master’s thesis looks at the effect of cadmium pollution on the soil mite Oppia nitens. [Paper 🔓️]


Attacobius lavape hanging out with fire ants • Mendonça, Pesquero, Carvalho, Arruda 2019
  • In Morrinhos, Brazil, nearly half of all Solenopsis saevissima fire ant colonies host a sinister guest: the only recently described corinnid spider Attacobius lavape. By constantly touching the ants, it manages to maintain chemical camouflage, and therefore feed on ant larvae and pupae undetected. They eat so many that they might be acting as a limit on the size of fire ant colonies. How freaking cool is that? [Paper 🔓️]
The mite Megalolaelaps colossus on its host, the green devil dung beetle Oxysternon conspicillatumCómbita-Heredia, O., Quintero-Gutiérrez, E.J., Romero-García, N. et al. 2020
  • How do you study mites that live on dung beetles in the lab when the mites need the beetles to survive, but the beetles die in captivity after a week? These researchers had to create innovative solutions to study the mysterious relationship between a mite and its host, the Colombian green devil beetle. [Paper] [Sci‑Hub]
  • Opilio canestrinii harvies, an invasive species in Northern Europe, are surprisingly omnivorous; a study shows “considerable inclusion of plant-derived sugar in the natural diet”. [Paper]
  • When a moth gets caught in a spiderweb, it can break free because the silk sticks to its tiny, loose wing scales that easily detach. But Cyrtarachne akirai, a spider that looks like bird poop, successfully catches moths with long, dangling silk threads. The glue in its silk is both runny and fast-setting, soaking through moth scales, then quickly hardening. Nala Rogers at Inside Science covers the new paper investigating how the glue works. [Paper 🔓️]



Neocheiridium gullahorumSammet, Kurina & Klompen 2020
  • The newly described pseudoscorpion Neocheiridium gullahorum is named after the Gullah people of South Carolina, where it was found. It’s the first Neocheiridium found outside the tropics. [Paper 🔓️]
  • Another far-flung arachnid: Lamellarea americana is a new oribatid mite found on live oak twigs in Florida, which is pretty weird considering that until now Lamellarea was only found in South Africa. [Paper 🔓️]
  • The folks at UNAM’s Laboratorio de Arañas have developed a protocol that uses an MS-DOS batch file, Perl, and Excel to grab photo metadata and generate biodiversity inventory websites “almost automatically”. You can download the resources and explore said websites in action. [Paper 🔓️]
  • Three new cave-dwelling harvies (Opilionids) from Minas Gerais, Brazil have appropriate names: Iandumoema gollum (like the previously described I. smeagol), I. stygia, and I. cuca.* [Paper]
    * There are several possible translation of “cuca”, ranging from the likely “roach” to others that are…less relevant. The paper’s not online yet, so we don’t know what the scientist’s explanation of the name is.


  • Over 500 pseudoscorpions collected several years ago in the Carpathians have been classified, adding to our knowledge of the pseudoscorpions of Poland. [Paper 🔓️]
  • Six new species of Hoplopholcus pholcid spiders from Cyprus, Greece, and Turkey. [Paper]


  • The second paper of a series on the spiders of Macaronesia catalogues spiders found in Madeira and Porto Santo, including Madeira’s laurisilva, the native laurel forests. [Paper 🔓️]
  • The dedications in this paper on seven new cave-dwelling Lepthyphantes species from Morocco are really quite sweet/poetic, particularly L. almoravidus, L. biospeleologorum, L. fadriquei, L. imazigheni, L. leknizii, and L. sasi. [Paper 🔓️]
  • Whoops. In 2016 a new jumping spider genus was named Kakamega (after its habitat, Kenya’s Kakamega Forest), but the name was already taken by a bird called the grey-chested babbler. The spider genus will now be known as Kakameganula. [Paper] [Sci‑Hub]
  • An entirely new family of mites, Bochkovocoptidae, found in the whisker follicles of Dent’s Vlei Rats from Uganda. [Paper 🔓️]
  • Two new species of galumnid mites, Galumna sandormahunkai and Pergalumna janosbaloghi, found in leaf litter in north Madagascar. [Paper 🔓️]
  • And two new parakalummid mites, Neoribates africanus and N. madagascarensis. [Paper 🔓️]
  • At 77 pages, this paper is an entire education on the water mites of Madagascar. [Paper] [Sci‑Hub]


Araniella mithra (left) and A. villanii (right), with A. nigromaculata in the middle • Zamani, Marusik & Šestáková 2020
  • Sure, Araniella villanii, the west/central Asian orbweaver named after the spider-loving mathematician Cedric Villani, gets all the press. Where’s the love for A. mithra, named for the Zoroastrian god of light? [Paper 🔓️]
  • A new ant spider, Zodarion izmirense, described from İzmir, Turkey. [Paper]
  • We didn’t know what the larvae of the micro-velvet mites Valgothrombium confusum and V. major, newly found in Turkey, looked like — until now. (Spoiler: like the adults, but smaller.) [Paper]
  • A new oribatid mite from west Kazakhstan is named Cosmocthonius oralensis. Bonus: we know what the juveniles look like, too. [Paper]
  • Another new oribatid from Kazakhstan: Dyobelba verae. [Paper]
  • A survey of a small lake in the suburbs of Chennai, India turns up 70 species! [Paper 🔓️]
  • Jumping spider specimens collected in Darjeeling, India over a hundred years ago belong to a new genus, Indopadilla. [Paper 🔓️]
  • Four new Lebertia water mites from China. [Paper]
  • A new liocranid spider, Jacaena jinxini, from Guangxi, China. [Paper 🔓️]
  • Two new oribatid mites, Arcoppia malaysiaensis and Oxyamerus niedbalai, identified from Malaysia, as well as 23 new species records. [Paper] [Sci‑Hub]

As always, thank you for reading; I apologize for the delay. Thanks to Sebastian Alejandro Echeverri for edits and proofreading! Comments, corrections, and suggestions are welcome; just drop us a line at @arachnofiles.


  • behavioural ecology: a field of science that asks (1) what are animals doing? (2) why? and (3) how are (1) and (2) affected by the animal’s interactions with its environment and other animals?
  • epiphyte: a plant that grows on another plant rather than in the soil. Orchids, bromeliads, and arums are just a few of the plant families that have epiphytic species.
  • haplogroup: a group of organisms within a species that share a haplotype.
  • haplotype: a set of certain variations in DNA that are (almost) always inherited together. Since these variations are inherited together, individuals that share a haplotype (that is, are in the same haplogroup) are likely to be related to each other.


Arachnids are fascinating. We write stores about these amazing animals, and the scientists that study them.

Neville Park

Written by

Local politics wonk turned arachnerd. •


Arachnids are fascinating. We write stores about these amazing animals, and the scientists that study them.

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