Arachnids Araneae Araneological research • Córdova-Tabares
et al. (2024) describe a
sac spider specimen from the
Mexican amber preserved with an ant belonging to the genus
Azteca, providing evidence of a fossil spider showing trapping and feeding behavior seen also in its extant relatives.
Ixodida Opiliones Opiliones research • Gainett
et al. (2024) report that extant daddy longlegs have six eyes, including four vestigial ones, and reevaluate the affinities of
fossil members of Opiliones with four eyes, resulting in older estimated ages of harvestman diversification.
Pseudoscorpiones Sarcoptiformes Schizomida Schizomid research • A study on changes of body size and shape diversity of male flagella in
Schizomida throughout their evolutionary history is published by Belojević
et al. (2024).
Scorpiones Scorpion research • Review of the higher classification of fossil scorpions is published by Dunlop & Garwood (2024) . • Lourenço & Velten (2024) report the discovery of
pro-juvenile specimens of
Betaburmesebuthus kobberti trapped together in a piece of Burmese amber, and interpret this finding as possible evidence that Cretaceous palaeoburmesebuthid scorpions produced litters with reduced number of offspring but including large pro-juveniles.
Trombidiformes Trombidiform research • Larvae of mites belonging to the group Erythraeoidea parasitising
gall midges (providing evidence of an association unknown in extant fauna) are reported from the Cretaceous amber from Myanmar by Arce
et al. (2024), who interpret this finding as indicative of shift of the host range of the studied mites after the Cretaceous.
Uropygi Other arachnids Other arachnid research • A study on the mouthparts of members of the genus
Palaeocharinus from the
Rhynie chert (
United Kingdom), providing evidence of the presence of a sophisticated mechanism for liquid feeding comparable to the filtration mechanisms of extant arachnids, is published by Long
et al. (2024). • A study on the structure of
cuticles of
Palaeocharinus, providing evidence of possible adaptations to terrestrial life, is published by Long
et al. (2024).
Eurypterids Eurypterid research • A study on the evolution of eurypterid body size is published by Ruebenstahl
et al. (2024), who find that giant size evolved independently in different eurypterid lineages, without clear relation to habitat or environmental drivers. • Bicknell
et al. (2024) describe new fossil material of Silurian and Devonian eurypterids from the Wallace Shale and Merrimerriwa Formation (
Australia), extending known geographical range of
Jaekelopterus into
Gondwana. • A diverse assemblage of eurypterid remains, including isolated
setae and
cuticular sheets with attached setae, is described from the Devonian Ora Formation (
Iraq) by Makled
et al. (2024). • Braddy (2024) studies the life mode of
carcinosomatoid eurypterids, interpreting them as slow-swimming ambush predators and mud grubbers, and interprets
megalograptids as likely more
basal than
carcinosomatids and
mixopterids. • Bicknell, Gaines & Hopkins (2024) describe a carcinosomatid specimen from the
Ordovician strata from the
Beecher's Trilobite Bed (
New York, United States) preserving the first evidence for
mesosomal musculature in eurypterids, and providing evidence that eurypterid musculature can be preserved in
pyrite. • Poschmann & Tollerton (2024) describe a new specimen of
Eysyslopterus patteni from the Silurian Rootsiküla/Saaremaa
Lagerstätte (
Estonia), providing information on the morphology of the
metastoma of the studied eurypterid. • Description of genital appendages of
Acutiramus macrophthalmus is published by Cheng & Briggs (2024).
Xiphosurans Xiphosuran research • A specimen of
Tachypleus syriacus preserved with intestinal contents transitioning into a
coprolite is described from the
Cenomanian Hjoula
Lagerstätte (
Lebanon) by Bicknell
et al. (2024).
Other chelicerates Other chelicerate research • Lustri
et al. (2024) describe new fossil material of
Bunaia woodwardi from the Silurian (Přídolí)
Williamsville Formation of the Bertie Group (Ontario, Canada), and interpret
B. woodwardi as a member of the family
Offacolidae. • Revision of the taxonomy, morphology and stratigraphical distribution of members of the genus
Limuloides is published by Howard (2024). • Sabroux
et al. (2024) revise the fossil material of Devonian
sea spiders from the
Hunsrück Slate (
Germany), providing new information on their anatomy and affinities, and find no compelling evidence of Pantopoda in the Devonian. == Crustaceans ==