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Arachnews: September 30, 2020

Your semi-regular roundup of arachnid art, news, events, and science.

Okay, I know I said this was going to be fortnightly, but there were like 200 items for July and then Life and a lot of Depression happened. In this edition: arachnologists on livestreams and podcasts; tarantula-keepers’ feedback wanted; #PruittData retractions; spiders eating lizards; lizards eating spiders; new species named after Gollum and Norman Platnick; and more.

Terms in bold are defined in the glossary at the end of the post. Some minor format changes: links to papers are now in the [Journal Title] that follows the story. Also, papers that are behind a paywall and not on Sci-Hub will be marked with a 🔒️, and papers that are open access or piratable will be the unmarked default.

Art & Social Media

Geminaria canalis, a bee fly that looks uncannily like a jumping spider and prey from behind. • Nevin Cullen
Sandonakid harvester by Jeremy Squire; wolf spider portrait by Michael Doe
Cellar spider and young by Jo Brown (see thread for more updates); soft tick with eggs by Matt Bertone
An Arctosa wolf spider dives underwater to hide (or maybe even hunt?) • Emanuele Biggi
A zebra jumping spider in bronze • D. Allan Drummond
Caution sign • @Meelsie143
An intriguing spider game in progress • Riley Neville

Education & Outreach

  • Leah (who you may know as @NaturalFitztory on Twitter), a volunteer with London’s Natural History Museum, has a live chat about spiders, answering people’s questions and showing some live specimens. [YouTube]
  • For the American Museum of Natural History’s Sci Cafe talk series, curator and arachnologist Cheryl Hayashi discusses the different types of spider silk and how it’s made, both in nature and in the lab. [YouTube]
  • For all you New England naturalists, there’s a new book out called A Backyard Book of Spiders in Maine, by Dana Wilde. [North Country Press]
  • Pedro Cardoso and Caroline Fukushima of the University of Helsinki are researching tarantula conservation and the pet trade. If you’re involved with tarantulas in any way—as a pet owner, a breeder, a scientist, a conservationist, etc.—please fill out their anonymous online survey. [Google Forms]

Events & News

The mystery spider, called the “strawberry button spider” for now. • Andrew Baxter
  • A very pretty red spider, possibly an undescribed species of theridiid or cyatholipid, has been found in South Africa’s Table Mountain National Park. Researcher Andrew Baxter says that if it does turn out to be a new species, he would like the naming rights to be auctioned off with proceeds going to habitat protection. [Cape Town Etc]
  • Vaccine company Valneva has announced that the Lyme disease vaccine they are developing did well in its first Phase 2 clinical trial. Results from the second trial, which used a longer vaccination schedule, should be coming in a few months. [New Scientist]
  • Our long national nightmare is over: Clarivate has restored Zootaxa’s impact factor score. [Retraction Watch]
  • The journal Molecules is calling for submissions for a special issue on natural and artificial silk. The deadline is January 31, 2021. [Molecules]
  • The Australasian Arachnological Society is now on Twitter! [Twitter]


Three papers have recently been retracted due to irregularities in data collected by researcher Jonathan Pruitt.

  • This 2016 paper on “keystone” Stegodyphus dumicola. In several datasets, numbers in one column were off from numbers in previous columns by the same exact amount (e. g., off by 3, 11, etc.). [Proc. R. Soc. B]
  • This 2014 paper on division of labour in Anelosimus studiosus colonies. Some data was duplicated: “identical behavioural profiles were repeated across individual spiders belonging to colonies that were purported to be independent.” [Animal Behaviour]
  • This 2013 paper on personalities of Stegodyphus sarasinorum colonies. In addition to duplicated data, “extensive overlap has been found between this data and that from a different article published the same year: 74.3% of the boldness values are identical to those found in the other publication even though different spiders were assayed.” They don’t say what that other paper was, but the most likely candidate is this Proc. R. Soc. B paper on the same species, which is currently under investigation. [Animal Behaviour]

Expressions of concern have been issued for two more papers:

Lastly, the Proc R. Soc. B editors would not agree to retract this 2016 paper on behavioural diversity of Anelosimus studiosus, so the other authors asked to have their names removed instead. Co-author Nick DiRienzo explains the decision on Twitter. [Proc. R. Soc. B]

For anyone keeping track, we are currently at six retractions, one correction, and one removal of authorship.



In Virginia, a researcher collects ticks by “flagging” • Thompson et al. 2020
  • The Asian longhorned tick (Haemaphysalis longicornis) is an invasive species that recently arrived in the US. And it brought a friend! At a Virginia farm where a bunch of cows died, researchers found a significant number of ticks were carrying the disease-causing parasite Theileria orientalis. However, that doesn’t necessarily mean the ticks passed the parasite on to the cattle; we’re still looking for a smoking gun. [Ticks and Tick-Borne Diseases] [Sci-Hub]
  • Okay, so you know how they turn salicylic acid (used in acne products to lightly exfoliate skin) into acetylsalicylic acid (aspirin)? If you do the same thing to carvacrol, the active ingredient in oregano oil, it’s slightly better at disrupting cattle tick (Rhipicephalus microplus) reproduction. [Natural Product Research] [Sci-Hub]
  • Diptilomiopid mites have mouthparts that are able to get into the inner layers of plants’ leaves, but their feeding normally doesn’t cause much harm. Not so for the case of the mite Rhynocus acerioides feeding on Capsicum chinense (a chili pepper); the plant did not survive. [Entomological Communications]
  • The predatory mite Neoseiulus barkeri likes eating red palm mite (Raoiella indica) eggs more than nymphs or adults. [Systematic and Applied Acarology 🔒️]

Spider Mites

  • Gotta love a paper that simply says what it is on the tin: “Spider mites cause more damage to tomato in the dark.” This is because the plants are sleeping. No, really. [Journal of Chemical Ecology]
  • A study in Benin found that, out of ten tomato varieties, the imported Buffalo cultivar and the local Tounvi were most resistant to the tomato red spider mite (Tetranychus evansi). [International Journal of Tropical Insect Science] [Sci-Hub]
  • Do spider mite-resistant corn varieties hold up as well when they’re parched for water? Yes, according to Gunbharpur Gill’s PhD thesis from Utah State University. [Utah State University]
  • Some two-spotted spider mites in commercial nurseries in south Florida have become resistant to three different acaricides. Yay! [Systematic & Applied Acarology 🔒️]
  • In a Japanese apple orchard, cutting back on mowing led to an increase in populations of predatory mites (Neoseiulus womersley)—and a corresponding decrease in spider mites (Tetranychus urticae and Panonychus ulmi). [Applied Entomology and Zoology] [Sci-Hub]
  • Sadly, you can’t solve everything with predatory mites. In Kenya, the invasive tomato spider mite (Tetranychus evansi) is so destructive to African nightshade (grown for its edible leaves) that many farmers have given up growing it entirely. These mites normally stay put. However, introducing the predatory mite Phytoseiulus longipes makes the mites move around to avoid it, possibly encouraging them to spread to other plants. [Sustainable Management of Invasive Pests in Africa] [Sci-Hub]
  • The almond spider mite (Schizotetranychus smirnovi), currently plaguing almond orchards in Iran, can produce 12–14 generations in a single season. That’s just one of the findings from a report on its life cycle. [Persian Journal of Acarology]

Venom & Medicine

  • Here’s a nice thorough overview of the biology and medical significance of Tityus stigmurus, a common (and dangerous) scorpion in northeast Brazil. This Spicy Boi is responsible for numerous deaths, especially in children and the elderly. The paper covers everything from basic natural history to how to raise it in the lab to the molecular makeup of its venom. [Toxicon] [Sci-Hub]
  • Better together — the venom of Cupiennius salei wandering spiders contains two types of neurotoxins, and while each type works OK by themselves, they are far more effective when mixed together! This ability might explain why the venom is this species is particularly strong. [Toxins]
  • Spider bites are quite rare, but when they do happen, it is helpful to know which species was involved. After being bitten by a false widow (Steatoda nobilis), a woman in Chile experienced radiating pain and went to the ER. After a few hours without being seen, they left — and she was fine after a few days. Normally, this isn’t a problem (as long as you’re in a country with a functional healthcare system). But this was a 5hr potential exposure to Covid-19. A quick ID of the spider could have cut this time down, as Steatoda bites rarely require emergency attention. [Revista Ibérica de Aracnología]
  • Despite their often intimidating size, tarantulas are not especially dangerous spiders. Getting bit can be painful, but doesn’t usually have long-term complications. Barring a rare anaphylactic reaction, the biggest risk is getting urticating hairs in your eyes. Here’s a review of medical treatment for run-ins with tarantulas. [StatPearls]
  • When and where do people (in Touggourt, Algeria) get stung by scorpions? Stings are most common from 10 a.m.–11 a.m., and on people’s arms and legs. Thankfully, the vast majority of stings (92.8%) caused only mild symptoms. [Epidemiology and Health]
  • Extremely rarely, the sting of a few scorpions (in this case Mesobuthus tamulus, which is found in India) might lead to bleeding inside your brain, which as you would guess, is fatal. However, early treatment can reduce or entirely avoid this risk. [The Egyptian Journal of Neurology, Psychiatry and Neurosurgery]
  • Which tick species carry Brazilian spotted fever, the deadliest rickettsia-type disease in the world? A new study found that, in the Brazilian state of Paraná, 5 different species can carry the disease, with about 1/10 of reported cases of the fever being fatal. [Ticks and Tick-Borne Diseases] [Sci-Hub]


  • There have been many experiments testing whether spider silk can inhibit bacterial or fungal growth — but there are many different types of silk with different chemical properties. Most spider silk research is done on tough, dry dragline silk. But the sticky capture threads of the Western black widow (Latrodectus hesperus) actually cause more bacterial growth! [Journal of Arachnology 🔒️]
  • Spider dragline silk is one of the strongest materials known, but it’s quite hard to make a lot of it — spiders are hard to farm for Various Reasons (such as eating each other). There’s been several efforts to use gene modification to make other, more farmable, animals (like goats) produce spider silk, but even those require lots of food and care. Photosynthetic bacteria, though? Scientists have managed to make the purple bacterium, Rhodovulum sulfidophilum, produce spider silk protein with just light, water, and air. [Communications Biology]


An icon, truly • Photo by José Roberto Peruca; edits mine
  • For a long time, people thought the Brazilian scorpion Tityus serrulatus was parthenogenetic—all female, capable of reproducing without fertilization. However, over the past twenty years a few bisexual populations have been found. Researchers looked at the chromosomes of males and females from bisexual populations to compare them to parthenogenetic females’. [Journal of Arachnology 🔒️]
  • Normally thought of as ambush predators, two species of Japanese crab spiders, Thomisus labefactus and T. kitamurai, have been found to also invade orb-webs to eat the architect! This discovery comes from observations from “non-peer reviewed articles, illustrated books and various sources on the internet”, including Twitter. [Invertebrate Zoology]
The wandering spider Phoneutria boliviensis has been photographed feeding on a wide range of animals • Valenzuela-Rojas et al. 2020
  • Roses are red,
    Spiders cause disquiet,
    Phoneutria boliviensis
    has quite the diverse diet. [Journal of Arachnology 🔒️]
  • A six-eyed sand spider (Sicarius thomisoides) was found eating a gecko in northern Chile, the first example of a spider from this family (Sicariidae) preying on vertebrates. Could sicariid venom have evolved to target vertebrates? (It is one of the few types that can affect humans.) [Revista de la Sociedad Entomológica Argentina]
  • Arachnids are key part of the food chain — many of them are predators on equally small or tinier animals, and also prey for larger ones. However, a lot of the research on this has focused on spiders. For the first time, scientists have found that pseudoscorpions are on the menu for lizards. [Revista Ibérica de Aracnología]
The snake Liopeltis calamaria is mostly fond of spiders • Narayanan et al. 2020
  • Nothing was known about the diet of the reed snake Liopeltis calamaria, so when the authors of this paper found one on the road in Tamil Nadu, India, they put it in a terrarium and offered it various things to eat. And I know we’re Team Arachnid here, but look how jazzed this snake is about eating spiders. [Records of the Zoological Survey of India]
  • The cobweb spiders Nihonhimea tesselata and Tidarren haemorrhoidale* live side by side in eucalyptus plantations in Brazil, but they capture very different types of prey: N. tesselata catches a lot of barklice, while T. haemorrhoidale mostly feeds on ants. The main differences: web design, and how far away from the tree trunk they build. [Journal of Arachnology 🔒️]
    * No, I don’t have any explanation for its name. I looked it up and everything. This was before it was customary for scientists to explain species names.
  • Our Own Catherine Scott’s PhD thesis on Western black widow (Latrodectus hesperus) courtship is online now. It covers how male black widows find mates and how females choose them. Three of the chapters have already been published as separate papers, a couple of which we’ve featured here (July 22, August 2019.) [University of Toronto]
  • Another PhD thesis from the Andrade Lab: Monica Mowery’s research on two invasive widow species, the Australian redback (Latrodectus hasselti) and the brown widow (L. geometricus). Redbacks have become established in various parts of southeast Asia, as well as Japan and New Zealand; brown widows have spread to many parts of the world, most recently California. What makes these spiders successful? How are the invasive populations different from ones in their native range? [University of Toronto]
  • How do harvesters locate each other in the wild? They might be using their sense of smell. Researchers in Brazil found that male Mischonyx cuspidatus harvesters followed the scent of other males, but not females; females, however, slightly preferred males. We may need to learn more about their ecology and life cycle to explain these results. [Journal of Arachnology 🔒️]
A Cocatus jumping spider guarding her eggs; omg look at the babies. • Naveen Iyer, Vasanthi Sametadka, in Ayer & Hill 2020
  • Look at how this Cocatus jumping spider lays its eggs along plant stems! [Peckhamia]
  • Jumping spiders are typically loners, but in a few cases, males and females are known to briefly live together. Adult males will find sub-adult females, and guard them (from other males), until the females molts into adulthood. Soon after molting, the male will mate with her, and then leave. This behaviour has been seen for the first time in the species Brettus cingulatus. [Peckhamia]


“The toy spider was purposely made to look silly to minimize threat.” • Chouinard & Stewart 2020
  • If someone hides your hand from view, shows you a rubber hand in about the same place, and brushes both the real and fake hands with a paintbrush — you will think the rubber hand is your own. Does putting a live huntsman spider on that rubber hand provide enough of a shock to prevent the Rubber-Hand Illusion? Nope! [Experimental Brain Research] [Sci-Hub]



  • The Chilean recluse (Loxosceles laeta) has recently turned up in the remote region of Aysén, Chile. It’s also showed up in Tierra del Fuego. Climate change may be enabling its spread. [Revista de la Sociedad Entomológica Argentina]
  • Researchers in Argentina have transferred a bunch of crab spiders to the genus Uraarachne: all the spiders in Plancinus, one from Runcinia, and one from Misumenoides. They also describe four new Uraarachne species from Argentina and Paraguay. [Revista del Museo Argentina de Ciencias Naturales]
  • A scorpion species found on Martinique and St. Lucia were long thought to be Didymocentrus lesueurii, but that was a misidentification. The species has been given its own name, D. martinicae. [Euscorpius]
  • A new phytoseiid mite described from the Brazilian state of Amazonas, Phytoseius feresi. Maybe it eats spider mites. [Systematic and Applied Acarology]
Iandumoema cuca, I. gollum, and I. stygia, newly described cave-dwelling harvesters from Brazil • Neves de Ázara et al. 2020
  • Three new species of Iandumoema harvesters from Minas Gerais, Brazil. These cave-dwelling arachnids were all given names appropriate to their habitat. I. cuca is named after the iconic character Cuca, an alligator witch (who lives in a cave). I. gollum, named after Gollum from The Lord of the Rings, takes its place alongside the already described I. smeagol. And I. stygia is, of course, named after the River Styx from the Greek underworld. [Invertebrate Systematics]
  • A gonyleptid harvester found in the fragmented cloud forests of Chapada Diamantina, northeast Brazil, represents not only a new species but a new genus: Paragoniosoma cachaceiro. [Zootaxa] [Sci-Hub]
  • Vima panita is a new species of harvester recently found in Caquetá, Colombia. The only other Vima species, V. insignis, lives practically on the other side of the continent in Guyana. This suggests that there might be other Vima species throughout South America. [Journal of Arachnology 🔒️]
  • A lot of species basically look identical and can only be told apart with genetic analysis. This seems to be the case with Heterophrynus tailless whipscorpions from French Guiana and Brazil. Comparing the same gene in 65 specimens of three Heterophrynus species showed that each species probably contains multiple distinct lineages, each belonging to a different region. That means one species with a wide distribution might actually be multiple species with small native ranges. This has big implications for wildlife conservation. [Zoological Research]


A beetle-mimicking Pachyballus jumping spider • Paul Bertner
  • Six new species of beetle-mimicking jumping spiders in Pachyballus and Peplometus described from across Africa. [ZooKeys]
  • A new palp-footed spider from Kenya belongs in a whole new genus; it’s called Sceliscelis marshi. [African Invertebrates]
  • Learn from previous arachnologists’ mistakes: if you’re outside eastern Africa, that wolf spider you think is Trochosa urbana is probably a different species. If you’re in Asia, consider T. dentichelis, T. ruricola, or T. ruricoloides instead. [Arachnology] [WSC]
  • A new huntsman genus from Tanzania, Platnickopoda, has been named after the late, great arachnologist Norman Platnick. [Arachnology] [WSC]
  • There’s a new checklist of spiders of Tanzania! It’s paywalled, but there’s a poor arachnologist’s version on iNaturalist. [Journal of East African Natural History 🔒️]
Buthus apiatus and its habitat in northern Algeria • Lourenço et al. 2020
  • A new scorpion species from northern Algeria, Buthus apiatus. [Revista Ibérica de Aracnología]
  • Leiurus quinquestriatus is one of Egypt’s most common scorpions. But genetic analysis of specimens collected from across the country suggests that there might actually be two different species, divided by the Nile. [Zoology in the Middle East] [Sci-Hub]
  • A new mesostigmatid mite found in sacks of corn in Egypt, Blattisocius flagellatus. [Zootaxa] [Sci-Hub]
  • A new oribatid mite found in leaf litter in Ethiopia, Galumna paracapensis. [Acarina]
  • A new tydeid mite, Lorryia pseudoplacita, found in snouted harvester termite nests in South Africa. Apparently this is a common mite habitat. [Acarina]
  • The tick species Rhipicephalus turanicus seems to contain three different lineages: one from Africa, one from southern Europe, and one from the Middle East and Asia. Now researchers are making the African lineage its own species, R. afranicus. It’s kind of weird that R. afranicus from Zambia and R. turanicus from Cyprus can interbreed, though. [International Journal for Parasitology] [Sci-Hub]


  • Are dysderid spiders in the genus Harpactea truly all descended from the same ancestor, or have a bunch of different lineages been arbitrarily bundled together? The discovery of three new species in caves in Italy and Croatia gave taxonomists an opportunity to test what exactly these spiders all have in common. Their analysis suggests Harpactea should be divided in three, to start with. [Systematics and Biodiversity] [Sci-Hub]
  • Five new species of Euscorpius scorpions from the Balkan Peninsula. There are also karyotypes for two of them, and apparently scorpion chromosomes are even weirder than spiders’. [Euscorpius]
  • 11 species of quill mites were found living inside feathers of birds from Ukraine for the first time. Also, the species Syringophilopsis acrocephali, previously known to live in swallow feathers, was found living on a new bird, the sand martin (Riparia riparia). This brings the total of Ukrainian quill mite species to 18. [Persian Journal of Acarology]
  • Pentamerismus oregonensis, a flat mite known as a garden pest, was found feeding on juniper in Kyiv, Ukraine. It causes unattractive yellowing in decorative plants. [Persian Journal of Acarology]
  • The pseudoscorpion Neobisium simile has been found in the UK for the first time, possibly imported by accident from continental Europe. [Arachnology 🔒️]


A Thiania jumping spider found in north-east India • Ahmed, Chakraborti & Hill 2020
  • A Thiania jumping spider, probably T. subopressa, has been found in an urban garden in Tripura, India, only the second of its genus found in India so far. [Peckhamia]
  • A new Glenognatha long-jawed orbweaver from India’s Western Ghats. Also, Pachygnatha silentvalliensis, so called because it was found in Silent Valley, has been reclassified as a pre-existing species, Tylorida marmorea. [Zootaxa] [Sci-Hub]
Tonsilla subyanlingensis, a newly described…*record scratch* agelenid?! • Liu et al. 2020
  • So I’m scrolling through this paper about two new Tonsilla funnel-weavers (family Agelenidae) from Jiangxi, China, looking for the photos, and…hold on, there must be some mistake, these are hacklemesh weavers (Amaurobiidae)! Aren’t they? It turns out that the subfamily they belong to, Coelotinae, has bounced between Agelenidae and Amaurobiidae for years. The most recent phylogeny places them solidly in Agelenidae, based on certain features of their anatomy and chromosomes. Anyway, welcome, T. jinggangensis and T. subyanlingensis. [ZooKeys]
  • The newly described Dolichognatha bannaensis is an unusual long-jawed orbweaver from Yunnan, China—unlike its eight-eyed brethren, it has only six eyes. [Zootaxa] [Sci-Hub]
  • Six new Belisana cellar spiders have been described from southern China; some were found under rocks in dark caves, others in domed webs under leaves. While most are from the coastal provinces of Guangxi, Guangdong, and Fujian, B. maoer is far inland in Sichuan. That suggests there’s more Belisana species in the provinces between them. [Zootaxa] [Sci-Hub]
  • There are also four new Belisana species described from southern Tibet. [Zootaxa] [Sci-Hub]
  • There are many obscure taxa that are officially described, but never revisited or found again. This was almost the case for Ametochilus, a genus of Southeast Asian wishbone spiders. Two species were described in 1887 and 1900; then, three more were found in 2016. Now researchers have described another, Atmetochilus songsangchotei from Thailand. They also collected specimens of A. fossor, the genus’s “flagship” species, so to speak, to replace type material that was lost. This is what it’s like when someone posts about a computer problem on a forum and the thread goes ignored for five years until, miraculously, another person posts a solution and the discussion is revived again. [Zootaxa] [Sci-Hub]
Latrodectus elegans, a widow spider recently found in Nepal • Shrestha & Dörr 2020
  • A species of black widow spider, Latrodectus elegans, has been found in Nepal for the first time—thousands of kilometres away from previous recorded locations. We don’t know if it’s native to Nepal, or if it was inadvertently brought in by humans. [Journal of Threatened Taxa]
  • The same authors have a new guide to scorpions of Nepal behind Arachnology’s impregnable paywall. [Arachnology 🔒️]
  • A new species of laelapid mite, Pogonolaelaps termitophilus, was found living on termites in Baluchestan, Iran. [Zootaxa] [Sci-Hub]
  • Several species of heterostigmatid mites were found on a wide variety of insects collected in Golestan, northern Iran—ants, flies, earwigs, and various beetles. Some of the mites had not been reported from Iran before; others were found on particular insects for the first time. [Persian Journal of Acarology]
  • Oribatid mites found in a peat bog in southwestern Siberia, Russia include two species of Banksinoma. Oribatids are common in bogs, but Banksinoma has previously only been found in dry habitats. Perhaps these were stragglers, or maybe Banksinoma is actually not that picky about habitat. [Acarina]
Some tick hosts: plateau pikas in Tibet (Tim Melling) and tanuki at the Imperial Palace (Imperial Household Agency).
  • A tick, Haemaphysalis flava, has been found on the grounds of Japan’s Imperial Palace for the first time. It probably dropped off a tanuki, or raccoon dog, which are known to live there. [Japanese Journal of Systematic Entomology]
  • In related “ticks on cute animals” findings, it seems that in Tibet, the Himalayan tick Dermacentor everestianus feeds on plateau pikas as larvae, and on yaks and sheep as adults. [Experimental and Applied Acarology] [Sci-Hub]
  • DNA sequencing can help find “hidden” species in populations that are difficult to tell apart otherwise. Researchers in Japan have sequenced the mitochondrial genomes for two species of Hygrobates freshwater mites—a first for Hygrobatidae, one of the major water mite families. [Mitochondrial DNA Part B]
  • A new pseudoscorpion from Xinjiang*, China, Dendrochernes mahnerti, is named after the prominent Austrian arachnologist Volker Mahnert, who passed away a few years ago. [Arthropoda Selecta]
    * In case anyone was wondering, the specimen’s from a remote lake in the Altai Mountains, nowhere near the secret internment camps recently found via satellite imagery. It was also collected some ten years before the current genocide really got going.
  • A female Rhagodes ahwazensis, a rare solifuge (camel spider) native to Iran, has been found for the first time. [Arthropoda Selecta]


  • Synsphyronus pseudoscorpions are found throughout Australasia. A new species, S. platnicki, has been found in New Caledonia. As you might have guessed, it, too, was named after Norman Platnick.[Arachnology 🔒️]
  • Two new species of oribatid mites, Anomaloppia babeldaobensis and Oxyoppia palauensis, found in a forest on Babeldaob Island, Palau. [Systematic and Applied Acarology 🔒️]

As always, thanks for reading, everyone! Thanks to Sebastian Alejandro Echeverri for edits. Corrections, additions, and other feedback are always welcome; just drop us a (silk) line at @arachnofiles. 🕷️


  • acaricide: a pesticide against mites and ticks.
  • bisexual: in the context of taxonomy, having two types of sex cells (eggs and sperm). (Yes, this is a different definition than in common language, and, yes, our editor was temporarily confused/bemused/intrigued by the write-up. It’s 2020, let us have this.)
  • dysderid: belonging to the spider family Dysderidae, commonly called “woodlouse (or your local term for terrestrial isopod) hunters”, although not all species specialize on this type of prey.
  • karyotype: a chart that shows the size and shape of each set of chromosomes an organism has.
  • mesostigmatid: belonging to the mite order Mesostigmata, part of the superorder Parasitiformes. Not all mesostigs are parasitic; the group also includes our predaceous pals the phytoseiid mites.
  • Phase 2 clinical trial: a stage of drug testing. Phase 1 is basically “is it safe? How much is safe?”; Phase 2 is “does it work?”; Phase 3 is “how well does it work?” After Phase 3, the drug may be approved.
  • parthenogenesis: in animals, reproduction with only eggs and no sperm. Typically, each sex cell chips in half the chromosomes, so going it alone requires genes to get parcelled out differently when egg cells are being formed.
  • type specimen or type material: the specimens collected when a species is officially described. They are preserved — for squishier creatures like spiders, that means popped in a vial of ethanol; for beetles, butterflies, etc., pinned on a card — and stored in a museum as the official representative of the species.
  • urticating hairs: fine barbed body hairs that almost all tarantulas from the Americas can kick or brush off in defence. It’s a bit like getting fiberglass in your skin, but the severity of the reaction depends on the species and individual reactions to the hairs. Essentially, urticating hairs are ranged weapons, while fangs are melée weapons. This may be why tarantulas from the Americas can afford to be more docile than tarantulas from Asia, Africa, and Oceania.



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