Arachnews: November 2019

Neville Park
Dec 30, 2019 · 19 min read

The month in arachnid art, news, and scientific research.

A small jumping spider peeps out from the edge of a leaf.
A small jumping spider peeps out from the edge of a leaf.
·oO • Matt Doogue, Twitter
Habronattus ustulatus, perfectly camouflaged in her native habitat, the dwindling coastal dunes of California. • Marshall Hedin, Twitter
The male and female of a new wolf spider genus, found in Little Desert National Park, Victoria, Australia.
A bolas spider swinging her bolas! • Miro Skandera, Instagram
A little amblypygid #FaceBug action. • Jordan Cadiot, Twitter
Pycnogonids are actually non-arachnid chelicerates, but close enough, right? • Meghan McCuller, Twitter

Education & Outreach


General arthropod stuff

A few items aren’t about arachnids specifically, but have important implications.

  • A widely reported study confirms staggering arthropod population losses in Germany, particularly associated with farmland. See coverage in Nature, DW, BBC, ScienceAlert, etc. [Paper] [Sci-Hub]
  • Relevant in light of many spiders’ surprising intelligence: an interesting argument that “increased cognitive abilities may evolve, not despite short lifespan, but because of it”. [Paper 🔓️]

Ancient history

A molecular clock-based spider “family tree”, calibrated only using fossils we can solidly classify. • Magalhaes et al, 2019
  • Scientists use spider fossils to help assign dates to “family trees” calculated with molecular clocks. But it’s often unclear how these fossils should be classified — do they belong to families that have since gone extinct, or are they the ancestors of living spiders? A lot of people’s work is based on wrong assumptions! Ivan Magalhaes and others went through allll the spider fossils to weed out the dodgy ones. They put together the handy chart above that shows when different branches diverged, and conclude that the groups of spiders that dominated in the age of the dinosaurs are much different from those that we see a lot of now. [Paper] [Sci-Hub]
  • A new “family tree” of soil mites (Acariformes) based on their mitochondrial genomes shows they go way, way back, supporting the hypothesis that they were among the first non-microscopic animals to live in the very first dirt as plants moved onto land. God, I love this stuff.[Paper] [Sci-Hub]
  • Mongolarachne chaoyangensis, a giant Cretaceous fossil spider found earlier this year, is a fake! The original fossil is a crayfish. [Paper]

Ecology & conservation

  • How do spiders spread out into farmland from natural or semi-natural habitats? In northern Italy, spiders that live in the woods can take well to hedgerows, orchards, and vineyards, but are unlikely to “spill over” into fields of crops. Spiders that live in meadows can adapt to fields more easily. This has interesting implications for spider-friendly land management. [Paper] [Sci-Hub]
  • When restoring habitat, it’s not enough to look at plant life — spiders can tell a different, complementary story. This study looked at restored heath in Brittany, France. [Paper] [Sci-Hub]
  • In Florida, wildflower plots increased the numbers of spiders, but not their diversity. [Paper] [Sci-Hub]
  • There’s more to biodiversity than just the number or variety of species in a given area. Another measure is beta diversity — the degree to which the region is a mosaic or a melting pot, to borrow a Canadian metaphor. Spiders have the ability to disperse over long distances by ballooning, which is interesting from an ecological perspective. Here’s a study of the differences between spider communities in the coastal wetlands of southern Brazil. [Paper] [Sci-Hub]
  • The centre-periphery hypothesis in ecology predicts that a species is more abundant and genetically diverse in the centre of its range than towards the edges. But when it comes to the mite Tetranychus truncatus, ecology and historical climate patterns are more important than geographic range. [Paper] [Sci-Hub]
  • In Algeria’s Chréa National Park, home to ancient cedar forests, “fires transform the forest into a mosaic of habitats, with open gaps of different stages of succession.” [Paper 🔓️]
  • An interesting PhD thesis on how mowing affects the spider populations in meadows. (Spoiler: not as much as you think.) [Paper 🔓️]
  • How harmful is the “invasive” red oak, brought from North America to Poland? This study found far fewer soil mites in stands of red oak than in native ones. [Paper 🔓️]
  • Related: a survey of soil mites in a former military training ground in northern Poland. [Paper 🔓️]
  • [Korean] Diving bell spiders, Argyroneta aquatica, have their own nature preserve in Eundae-ri, Korea. Invasive apple snails are eating the underwater plants, which might be bad for the spiders. [Paper 🔓️]
  • [Korean] Related: a VR fieldwork class introduces middle school students in Korea to the diving bell spider. [Paper 🔓️]

Pest control

  • Experiments on guinea pigs show that the dog tick Dermacentor variabilis can transmit Rickettsia rickettsii, the bacteria that causes Rocky Mountain spotted fever, much faster than previously thought. Coverage: Entomology Today. [Paper 🔓️]
  • The cattle tick Rhipicephalus microplus takes a huge economic toll on Brazil’s massive cattle industry (a key driver of deforestation and carbon emissions). Using chemicals to kill them has just created chemical-resistant ticks. A ghoulish possible solution that’s been used with other agricultural pests: spreading dead insects laced with entomopathogenic nematodes in the grass where the ticks lay their eggs. Good news for cows; bad news for ticks, the forest, and the climate. [Paper] [Sci-Hub]
  • The disease-causing parasite Theileria found in ticks on goats in Malaysia. [Paper]
  • A study on ticks found on cattle across Indonesia. [Paper 🔓️]
  • The phytoseiid mite Neoseiulus californicus is used in agriculture as pest control; it specializes in eating spider mites. Researchers often need to study how they react to ingested chemicals. This experiment tested the most effective way to feed them. [Paper 🔓️]
  • It’s a mite-eat-mite world. Cheyletus malaccensis is a mite that feeds on Aleuroglyphus ovatus, a mite that commonly infests stored foods. To assess how it could be used as biological pest control, these researchers studied C. malaccensis’ snacking habits. [Paper] [Sci-Hub]
  • The spider mite Tetranychus urticae, a major pest, reproduces especially fast at high temperatures. Luckily, so does the predatory phytoseiid mite Amblyseius andersoni. [Paper 🔓️]
  • Related: the phytoseiid mite Neoseiulus longispinosus will eat Tetranychus neocaledonicus, but its preferences change with life stage. Nymphs prefer to prey on other nymphs, but adults would rather eat the eggs. [Paper 🔓️]
  • Spider mites live fast and die young—on average males live three days, females live six. This thesis explores the different factors that affect aging in T. urticae. [Paper 🔓️]
  • Some plants infested by pests release chemicals that attract the pests’ predators. One question is whether crops that have been genetically modified to confer insect resistance have the same ability. It turns out ordinary corn and Bt corn differ in their chemical responses, but the predatory mite Neoseiulus californicus apparently doesn’t care about either. [Paper 🔓️]
  • Managing Varroa bee mites with various essential oils. I would have liked to see a neutral oil, like mineral oil, used as a control in this experiment, but oh well. [Paper️ 🔓️]
  • What’s the best way to test acaricide resistance in cattle ticks? [Paper 🔓️]
  • Datura metel, a plant in the nightshade family, has lots of fun toxic compounds that show promise for controlling ticks like Hyalomma schulzei. [Paper 🔓️]
  • Wolf spiders killed flies contaminated with neonicotinoid pesticides, but didn’t eat them. [Paper 🔓️]
  • More tests of acetylcarvacrol, a hopefully less toxic-to-mammals version of carvacrol, an acaricide (tick/mite-killer) derived from oregano and thyme oil. [Paper] [Sci-Hub]
  • The pesticide azadirachtin and a “toothache plant” botanical extract work better together than when used separately to control red spider mites on eggplant. [Paper]
  • Alien vs. predator! The non-native mite Amblydromalus limonicus is used to control thrips in European greenhouses, but it will also attack the larvae of a native predatory mite, Amblyseius andersoni. [Paper]
  • Can scientists see why four different spider species love the taste of C̶i̶n̶n̶a̶m̶o̶n̶ ̶T̶o̶a̶s̶t̶ ̶C̶r̶u̶n̶c̶h̶ Chrysodeixis acuta, a noctuid moth whose larvae are soybean pests? [Paper 🔓️]

Venom, disease, and health

  • A thorough overview of what we know about spider venom and how scientists analyze it. [Paper 🔓️]
  • Related: a more general look at venom throughout the animal kingdom. [Paper 🔓️]
  • The black-legged tick, Ixodes scapularis, can carry bacteria that cause Lyme disease, babesiosis, and other diseases, and its range continues to spread. Over nine years, Saskatchewan scientists and public health officials collected tens of thousands of ticks, both sent in by members of the public and sampled from different sites across the province. Nearly all of the ticks they found were American dog ticks (Dermacentor variabilis). Only a few were I. scapularis, probably carried by birds; of those, only about 15% were had disease-causing bacteria. Black-legged ticks don’t live in Saskatchewan yet, but it is important to keep an eye out. [Paper]
  • A two-year study of tick bites recorded in a nature reserve in Brazil. [Paper] [Sci-Hub]
  • Five years of tick bites reported in the United Kingdom. [Paper] [Sci-Hub]
  • Can people potentially get Rocky Mountain spotted fever and Lyme disease from camel ticks in Saudi Arabia? Yes! [Paper 🔓️]
  • So we know that dust mites can aggravate people’s allergies, but what exactly are they allergic to? It turns out that one reason it’s been hard to get a handle on allergenic compounds is that male and female mites express different proteins. [Paper 🔓️]
Phoneutria boliviensis on the prowl. • Universidad EAFIT, Flickr
  • Phoneutria wandering spiders are one of the few kinds of spiders whose venom is dangerous to humans. It turns out that the venom of Phoneutria boliviensis is more toxic to vertebrates (geckos) than invertebrates (cockroaches); this might be why humans are so susceptible to it. [Paper 🔓️]
Also, look at this thingy they built to milk spider venom. Just look at it. • Valenzuela-Rojas et al 2019
  • How did scorpion venom evolve? Scientists have commonly thought that venom proteins began as versions of proteins used for everyday cell functions, and over time evolved to become more toxic. A new analysis finds that the genes for these proteins are under evolutionary pressure to stay the same. [Paper 🔓️]
  • In some scorpions, males and females have differently shaped claws and stingers. How does it affect their ability to pinch and deliver venom? Are there sex differences in their venomousness as well? [Paper] [Sci-Hub]
  • A young woman in Missouri experienced an unusually severe reaction to a presumed brown recluse bite. There’s photos of the necrotic lesions if you want to evaluate how legit they are. (Also, don’t worry, she got better.) [Paper] [Sci-Hub]
  • A great overview of Loxosceles similis, a medically significant recluse spider in Brazil. Learn about the biochemical and genetic basis of its venom, as well as the ecological and epidemiological aspects that are increasingly bringing humans and L. similis together. [Paper] [Sci-Hub]
  • Spider bite or infection? As usual, it’s staph. ¯\_(ツ)_/¯ [Paper]
  • “Eye trapped an arachnid: Horrific but true!” Now that’s how you title a paper. An Indian guy who had had his eye removed had a dead spider found in the socket. “Patient was counseled regarding the importance of adequate maintenance of personal and socket hygiene.” Warning: picture of dead spider in guy’s eye socket. [Paper 🔓️]


Real-time depth estimation using a salticid-inspired sensor. • Qi et al, 2019
  • Unlike most animals, jumping spiders can tell how far away things are with just one eye (we need to use both of ours for depth perception). Now, scientists have designed a depth sensor inspired by the spider’s eye. Covered by SciTechDaily. [Paper 🔓️]
  • A flexible, self-powered wind sensor based on the sensitive hairs on spiders’ legs. [Paper] [Sci-Hub]
  • A design for a spider-like “octopod” robot. [Paper 🔓️]
  • Fun with engineered spider silk protein! Researchers in Germany created nanometre and micrometre-thin films of the catchily named eADF4(C16) to examine their structural properties. [Paper] [Sci-Hub]
  • Silk-based gene carriers. Spider silk foams for wound healing scaffolds. Coating implants in spider silk to reduce infection. Here’s a chapter about some seriously cool biomedical uses of spider silk protein (p. 187 on). [Paper] [Sci-Hub]

Sex & reproduction

  • Until very recently, scientists thought that the reproductive organs in male spiders’ pedipalps lacked nerves. Now, the team that brought us the first evidence of palpal organ nervous tissue investigates 9 more species, finding nerves in all of them! “Sensitive palpal organs expand the sensory capacity of male spiders during mating beyond what was considered possible.” [Paper 🔓️]
  • Male Manogea porracea orbweavers mature earlier in the season than females, and can court both juvenile and adult females. Larger males gravitate to larger adult females, but the size of juvenile females doesn’t seem to matter. Could pheromones play a role? [Paper 🔓️]
  • Eating for 100? Gravid (pregnant with eggs) long-jawed orbweavers eat more midges than non-gravid ones. [Paper] [Sci-Hub]
A brief clip of Schizocosa retrorsa’s mating display, which sends visual and vibratory signals. • Eileen Hebets
  • Like other Schizocosa wolf spiders, S. retrorsa performs elaborate mating displays involving leg-waving and pedipalp drumming. Unlike other Schizocosa, this mating display doesn’t seem to actually…do…anything? Like, how clearly females can see and feel this performance has no connection to how successful the males are. The authors of this study call it a “mismatch between signal transmission and signal function”. It’s a bit more than I can effectively summarize here, so do read the full thing. [Paper] [Sci-Hub]


The European wasp spider hosts a mysterious bacteria passed from parent to offspring. • Fablegros, Pixabay
  • A study of the wasp spider’s microbiome turns up a bacterial endosymbiont so different from other species that it probably represents a new branch of the bacterial “family tree” and is probably transmitted vertically—from mother to offspring. [Paper 🔓️]
  • More endosymbionts! In Dermacentor silvarum, an Asian cousin of the North American dog tick, eggs, larvae, nymphs, and adults all had different microbiota. One kind of bacteria, Coxiella, seems to be vertically transmitted. [Paper] [Sci-Hub]
  • Did you know the football “huddle” was invented by deaf football players so they could plan plays without the other team seeing what they were saying? Stegodyphus dumicola, social velvet spiders, also huddle before team hunts. But for these vibrationally-attuned spiders, it’s about staying still so they can better “overhear” the movements of their prey. [Paper]
  • A white crab spider, camouflaged on a white flower, waits for an unsuspecting bee to land. That’s the story—but in reality it seems to be more complicated than that. This study finds that insects avoid flowers with spiders on them regardless of colour and seem to recognize their shape. [Paper]
A male Habronattus pyrrithrix displays his red face and green underlegs—but not his striped abdomen—to a female. • Taylor, Cook & McGraw 2019
  • Habronattus jumping spiders with more wasp/bee-like colouration also spend more time waving their legs like antennae, indicating that defensive mimicry might be going on. [Paper 🔓️]
  • The hover wasp Parischnogaster, found throughout southeast Asia, has a dangerous way of making a living: it steals prey from spiders’ webs, a behaviour called kleptoparasitism. How do they avoid getting caught in webs themselves? Are some webs easier to steal from than others? Learn from the ultimate shoplifters. [Paper] [Sci-Hub]
A giant fishing spider, Ancylometes rufus, eating a poison frog, Ameerega trivittata. • Ramos-Torres & Caicedo-Moncada 2019
  • Roses are red,
    Amphibians like bogs,
    Giant fishing spider
    found eating poison frog.
    [Paper 🔓️]
Erginulus harvestman leg dabbing. By me, based on this iNaturalist pic by Gabriela Angelica Martinez Castro.
  • “[Erginulus clavotibialis] adults and penultimate nymphs rarely exhibited leg dabbing, an unusual behavior generally associated with cosmetid harvestmen.” I’m sorry…I had to. [Paper] [Sci-Hub]
  • Hangry hangry harvestmen. When hungry, the harvestman Mischonyx cuspidatus behaves more erratically. [Paper] [Sci-Hub]
  • In the Arctic, fast-changing environmental conditions are shaping spider behaviour. According to this thesis, climate change may lead to the spiders of south-west Greenland becoming more risk-averse. See also: Arctic wolf spiders eating more springtails (Koltz et al 2018); tropical storms creating more aggressive spider colonies (Little et al 2019). [Paper]
“A glimpse into just how bright these Cranaidaecan appear in natural-type settings.” • Arguello 2019
  • Scorpions are not the only arachnids that fluoresce under UV light. Check out these fluorescent opilionids from Trinidad! [Paper 🔓️]
  • I was today years old when I learned that the grey wall jumper Menemerus bivittatus can stridulate! [Paper]
  • Explore the ebbs and flows of the invisible odor landscape inhabited by amblypygids in Florida and Costa Rica. [Paper 🔓️]
  • It’s not the heat, it’s the humidity. Cattle ticks (Rhipicephalus annulatus) in south Texas depend on humidity and ground cover to hatch and survive until they find a host. [Paper 🔓️]
  • The closely related but more tropical species Rhipicephalus microplus can survive months without food. Genetic analysis offers some clues. In starving larval ticks, genes related to autophagy—breaking down cells and recycling their contents—are periodically activated every 10 to 15 days. [Paper] [Sci-Hub]
  • What’s with ticks on Amazonian caimans? After reports of a few finds, these researchers did a thorough search and concluded it’s probably not A Thing — only a few caimans had ticks, possibly picked up while caring for eggs (which means more time spent on land, ticks’ preferred element). Neat, though. [Paper] [Sci-Hub]
  • “Do tarantulas eject silk from their feet?” In another case of Betteridge’s Law, the answer is no. “Irritated” tarantulas* walking on vertical walls leave behind microscopic “footprints” of fibrous material which some researchers have claimed to be silk. Other researchers claimed those researchers were talking out of their ass. Recently, researchers in Czechia examined the “footprints” with a scanning electron microscope and found that they are made of broken-off bits of the fine hairs on the pads of spiders’ feet, glued together with a secretion—sticky, but not silk—that may come from inside the hairs. [Paper 🔓️]
    * Yes, it’s important that they’re irritated.
  • A comparison of various arthropod sit-and-wait traps—antlions, glowworms, caddisflies, and spiders. [Paper 🔓️]
  • Scorpions vs. antlions! [Paper]
  • An intriguing-looking article on how social spiders decide to disperse. [Paper]
  • A newly discovered gene, FoxB, plays an important role in arthropod development; it affects the bottom side of limbs in distantly related species like fruit flies, beetles, and spiders. If it’s turned off, their legs come out all fucked up, looking like “bandyklubba”—Swedish for the sticks used in bandy, a Northern European version of hockey. [Paper 🔓️]
  • Mites and ticks’ genome sizes are hugely variable. In general, the larger a species’ body size, the larger its genome; and ticks have much larger genomes than mites. We don’t really know why yet. [Paper 🔓️]
  • Observations of magnolia green jumping spiders (Lyssomanes viridis) from the University of Costa Rica back up reports that they take a whole year to mature! [Paper 🔓️]
  • Three words everyone wants to hear: radioactive Jōrō spiders. [Paper 🔓️]



An example of the Spider Anatomy Ontology • Ramírez & Michalik 2019
  • Ramirez & Michalik have developed an anatomical ontology for spiders — a sort of standardized glossary for body parts and how they relate to each other, which can be used by computer programs as well as humans. [Paper 🔓️]
Long-jawed orbweaver’s toothy fangs, pic by me; xkcd, “Standards”.
  • One of the defining features of Tetragnatha long-jawed orbweavers is—you guessed it—their long jaws (chelicerae). Sometimes you can only tell species apart by comparing the “teeth” on their chelicerae. The problem is, taxonomists all have their own ways of referring to the teeth, making it hard to compare descriptions. A new paper proposes standardized terminology for everyone to use going forward. [Paper 🔓️]
  • Same dealio, but for New World tarantulas’ urticating hairs, which are basically teeny tiny porcupine quills covered in irritating barbs. They use their back legs to brush clouds of them into the air as a defence mechanism. [Paper 🔓️]


The “Honduran curly-hair tarantula” gets a new scientific name. • Andreas Beier, Flickr
  • Several species formerly in the Central American tarantula genus Brachypelma have been moved to a new genus, Tliltocatl. They include T. albopilosum and T. vagans, two species common in the pet trade. Non-Nahuatl-speaking tarantula fans the world over are grappling with the pronunciation of Tliltocatl. This is a developing story, please stay tuned. [Paper] [Sci-Hub]
  • Pale, spindly, almost eyeless harvestpeople recently found in the Andes are the remnants of a distant gonyleptoid lineage surviving in lava tube caves. They’ve been placed in their own family, Otilioleptidae. Gizmodo calls them “Gollum-like”; my first thought was The Descent. [Paper 🔓️]
    (Previously: Trogloraptoridae, a new family discovered in caves in the Pacific Northwest.)
  • I think this may be the first undergraduate paper that’s crossed the Arachnofiles desk*! A survey of the spider fauna of a Virginia university campus turns up representatives of 43 genera across 16 families, “with a relatively low sampling effort”. [Paper 🔓️]
    * “crossed the desk” = “turned up in a spreadsheet generated from Google Scholar alerts”
  • A new vaejovid scorpion, Kochius colluvius, found in Arizona. [Paper 🔓️]
  • New tarantula from Mexico’s Sierre Madre Occidental, Aphonopelma bacadehuachi, related to species from the magical-sounding “Sky Islands”. [Paper] [Sci-Hub]
  • A new scorpion, Centruroides possanii, found in Colima, Mexico. Possibly endangered. Possibly medically important. [Paper] [Sci-Hub]
  • When it comes to Uropodina mites in the tropics of the Americas, we’ve only just scratched the surface. [Paper 🔓️]
  • A female Diplocentrus lachua scorpion found for the first time, in Guatemala. [Paper 🔓️]
  • This quick survey of the spiders of the ABC Islands (Aruba, Bonaire, and Curaçao) is the first update in over 130 years. [Paper 🔓️]
  • Feather mites found on various wild birds in a state park in Brazil. [Paper 🔓️]
  • The phytoseiid mite genus Leonseius has, quote, a “troubled taxonomic history”. [Paper]
  • The social spider Anelosimus jucundus found in Ceará, Brazil for the first time. [Paper 🔓️]
  • Likewise with the crab spider Epicadus trituberculatus. [Paper 🔓️]
  • A new oribatid mite, Zeasuctobelba processa, from sphagnum moss in Patagonia. [Paper 🔓️]


  • Introducing, a free online catalog of Italian spiders. You can browse by taxon or by geographic area. [Paper 🔓️]
  • The water mites (Hydrachnidia) that live in the springs of Europe are more diverse than they look. A DNA barcoding project suggests there may be over a hundred new species waiting to be described. [Paper 🔓️]
  • Related: This also seems to be the case with Hydrodroma water mites from Europe and North America. [Paper 🔓️]
Larvae of Oudemansidium komareki on the bat Pipistrellus kuhlii. • Stekolnikov & Quetglas 2019
  • Poor Spanish bats, infested with chigger mites. [Paper 🔓️]
  • Many moss mites multiply in mire. [Paper] [Sci-Hub]
  • Rock-flipping in Bulgaria turns up a new titanoecid spider, T. deltshevi. [Paper 🔓️]
  • A new Tetranycopsis mite species is Hungary for grass. I’m sorry. [Paper 🔓️]
  • The male of Euscorpius feti described for the first time, in Croatia. [Paper 🔓️]
  • The nymphs of soil mite Caleremaeus monilipes “carry the exuvial scalps of previous instars on the gastronotum, using a cornicle”. I don’t know exactly what that means but it sounds pretty metal. [Paper]
  • A female Zelotes occultus ground spider, a species known only from male specimens, found in Russia. [Paper 🔓️]


  • A quick survey of ticks on cattle in Sudan’s Northern State, the first in 60 years, turns up nine species. [Paper 🔓️]
  • A survey of ticks found on elephants from Kenya, Mozambique, Zimbabwe, and the Republic of Congo. The ticks could only be collected while the elephants were sedated and restrained for transport, and records are incomplete: “No total collections of ticks were made from any of the elephants because of the size of the animal, the shortage of workforce, difficult operating conditions and the usually short period between sedation and resuscitation.” [Paper 🔓️]
  • Seven species of the goblin spider Opopaea found in Kenya, five of which are new to science. [Paper 🔓️]
  • The Madagascar jumping spider Homalattus insularis should actually be Colaxes insularis. [Paper 🔓️]
  • From South Africa, a newly described genus of mites ride around on termites! [Paper]


  • The sixth instalment of Zamani & co.’s surveys of the spiders of Iran; Zoropsidae (false wolf spiders) found for the first time. [Paper 🔓️]
  • And here’s an updated list of ticks of Iran. [Paper]
  • What the heck is a Kenyan huntsman spider doing in Iran?! [Paper 🔓️]
  • “The first attempt to generate genome sequence data and to develop SSR markers for Hyalomma marginatum”, a tick of medical significance in Turkey. [Paper]
  • This newly described solifuge from Turkey is surprisingly fuzzy. [Paper] [Sci-Hub]
  • DNA barcoding a Eurasian harvie, Nelima pontica. [Paper 🔓️]
  • A new Rickettsia bacterial genotype was detected in a soft tick from a bat in Pakistan. [Paper 🔓️]
  • A new checklist of spiders in the Northern Western Ghats, Maharashtra, India. [Paper]
  • A survey of the spiders along the Charghad River in Amravati District, Maharashtra, India. [Paper 🔓️]
  • A survey of spiders in suburban South Bangalore, Karnataka, India. [Paper]
  • A survey of spiders in Malavagoppa, a village in Karnataka, India. [Paper 🔓️]
  • A survey of spiders from the rice fields of Varanasi, India. [Paper]
  • A few water mites newly found in the Himalayas, in India’s Uttarakhand State. [Paper]
  • Tetranychus neocaledonicus, a pest of fruits and vegetables throughout India, spotted on apples. [Paper 🔓️]
  • Three new Parasyrisca ground spiders in Western Mongolia. [Paper] [Sci-Hub]
  • Two new Dipoena cobweb spiders fround in China’s Wuling Mountains. [Paper 🔓️]
  • A new Apoplophora oribatid mite found on Hainan Island, China. [Paper] [Sci-Hub]
  • Six new torrenticolid water mites described from Guizhou, China. [Paper] [Sci-Hub]
  • Two new species of eriophyid mites found on some rather pretty flowers, Bauhinia and Combretum, in China. [Paper] [Sci-Hub]
The newly described Liphistius pinlaung in its native habitat. • Aung KPP et al. 2019
  • Two new Liphistius segmented trapdoor spiders, very cool “living fossils”, from Myanmar! [Paper 🔓️]
  • Related: a revision of Heptathela, liphistiid spiders native to Japan, results in twelve new species. [Paper 🔓️]
  • Related: three new species of segmented trapdoor spiders in Hunan, China. These are also cool, but the photos aren’t as good. [Paper] [Sci-Hub]
  • Also some new phytoseiid mites from Myanmar, which are okay I guess. [Paper]
A grey-headed woodpecker and, presumably, its feather mites. • Tony Castro, Wikimedia
  • Two new species of feather mite found on grey-headed woodpeckers in Korea. [Paper] [Sci-Hub]
  • A new dwarf spider genus, Singatrichona, found in Singapore. [Paper 🔓️]


  • The author of this paper on mites found on New Zealand birds thanks his cats for allowing access to their prey. Lmao, but seriously, on behalf of our birder brethren, we implore you to keep your cat inside unless supervised. [Paper 🔓️]

Congratulations, you made it to the end! This is truly more arachnid content than any one mortal should be able to process in one sitting, which is why going forward Arachnews will be published weekly.

Corrections, ideas, and items are welcome! Seriously, send in your papers and art and stuff. Leave a comment or drop us a (silk) line on Twitter at @arachnofiles.


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

Neville Park

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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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