Nature's disguise: Empirical demonstration of dead-leaf masquerade in butterflies.

Animals deploy diverse color-based defenses against predators, including crypsis, mimicry, aposematism, and masquerade. While crypsis, mimicry, aposematism have been extensively studied, the strategy of masquerade-where organisms imitate inedible or inanimate objects such as leaves, twigs, stones, and bird droppings-remains comparatively underexplored, particularly in adult butterflies. The Indian oakleaf butterfly ( ) exemplifies this phenomenon, with its wings resembling dead leaves, providing a classic example of natural selection.

Nephila spider male aggregation: preference for optimal female size and web clustering.

Sexual size dimorphism theory predicts biased operational sex ratios (OSRs) and an uneven distribution of males among certain females. We studied this phenomenon through a field census of the giant wood spider Nephila pilipes (family Nephilidae) in Singapore, a species where females are, on average, 6.9 times larger than males.

Four new species of the spider genus (Araneae, Mesothelae, Liphistiidae, Liphistiinae) from Myanmar.

Four new species of belonging to the species group are described from Myanmar based on both sexes: Zhan & Xu, (♂♀), Zhan & Xu, (♂♀), Zhan & Xu, (♂♀) and Zhan & Xu, (♂♀). Currently, Myanmar stands as the westernmost country where is distributed, with the new species being found in the westernmost region of Myanmar.

Spiders manipulate and exploit bioluminescent signals of fireflies.

Predators often search for prey while moving through the environment, but there are important exceptions, including the way sedentary predators sometimes rely on signals for drawing prey to within striking distance. Some spiders, for instance, leave the remnants of previously-captured prey in their webs where they function as static lures that effectively attract a diverse array of additional prey. However, important questions remain concerning how specific the targeted prey may be and how dynamic, instead of static, signalling might be.

Seven new species of the segmented spider genus (Mesothelae, Liphistiidae) in Thailand and Myanmar.

Seven new species of the primitive segmented spider genus are described and assigned to species groups based on characters of the male palp and vulva plate. The group includes Sivayyapram & Warrit, (♂♀) from southeastern Myanmar, Sivayyapram & Warrit, (♀) from northwestern Thailand, and Sivayyapram & Warrit, (♀) from western Thailand; the group (Complex A) contains Sivayyapram & Warrit, (♂♀), Sivayyapram & Warrit, (♂♀), Sivayyapram & Warrit, (♂♀), and Sivayyapram & Warrit, (♂♀) from central Thailand.

Antipredator defences in motion: animals reduce predation risks by concealing or misleading motion signals.

Motion is a crucial part of the natural world, yet our understanding of how animals avoid predation whilst moving remains rather limited. Although several theories have been proposed for how antipredator defence may be facilitated during motion, there is often a lack of supporting empirical evidence, or conflicting findings. Furthermore, many studies have shown that motion often 'breaks' camouflage, as sudden movement can be detected even before an individual is recognised.

Eyeless cave-dwelling spiders still rely on light.

Subterranean animals living in perpetual darkness may maintain photoresponse. However, the evolutionary processes behind the conflict between eye loss and maintenance of the photoresponse remain largely unknown. We used spiders to investigate the driving forces behind the maintenance of the photoresponse in cave-dwelling spiders.

Background matching can reduce responsiveness of jumping spiders to stimuli in motion.

Motion and camouflage were previously considered to be mutually exclusive, as sudden movements can be easily detected. Background matching, for instance, is a well-known, effective camouflage strategy where the colour and pattern of a stationary animal match its surrounding background. However, background matching may lose its efficacy when the animal moves, as the boundaries of the animal become more defined against its background.

Three new species of the primitively segmented spider genus (Mesothelae, Liphistiidae, Heptathelinae) from Hunan Province, China.

Three new species of the primitively segmented spider genus Ono, 2000 are identified and described from Hunan Province, China, based on morphological characters of males and females: Zhang & Xu, (♂♀), Zhang & Xu, (♂♀), and Zhang & Xu, (♂♀). All the new species belong to the -group according to male palp and female genital morphology.

Three new species of the spider genus (Araneae, Mesothelae, Liphistiidae) from Thailand.

We diagnose and describe three new species of the primitively segmented spider genus from Thailand, based on male palp and female genital morphology: Zhan & Xu, (♂♀), Zhan & Xu, (♂♀), and Zhan & Xu, (♂♀). The classification of the three new species of is discussed: and are assigned to the -group, and is placed in the -group according to male palp and female genital morphology.

Males armed with big weapons win fights at limited cost in ant-mimicking jumping spiders.

A core assumption of sexual selection theory is that sexually selected weapons, specialized morphological structures used directly in male contests, can improve an individual's reproductive success but only if the bearer can overcome associated costs, the negative effects on the bearer's fitness components. However, recent studies have shown that producing and wielding exaggerated weapons may not necessarily be costly. Rather, some traits can be selected for supporting, or compensating for, the expense of producing and wielding such exaggerated weapons.

Male mating strategies to counter sexual conflict in spiders.

When sexual conflict selects for reproductive strategies that only benefit one of the sexes, evolutionary arms races may ensue. Female sexual cannibalism is an extreme manifestation of sexual conflict. Here we test two male mating strategies aiming at countering sexual cannibalism in spiders.

Masquerading predators deceive prey by aggressively mimicking bird droppings in a crab spider.

In aggressive mimicry, a predator accesses prey by mimicking the appearance and/or behavior of a harmless or beneficial model in order to avoid being correctly identified by its prey. The crab spider genus is often cited as a textbook example of masquerading as bird droppings (BDs) in order to avoid predation. However, spiders may also aggressively mimic BDs in order to deceive potential prey.

Phylogenetic placement and species delimitation of the crab spider genus Phrynarachne (Araneae: Thomisidae) from China.

Evolutionary biologists have long been fascinated by the striking resemblance to bird droppings of the sit-and-wait crab spiders of the genus Phrynarachne. In doing so, species of Phrynarachne have evolved not to avoid detection, but rather, to cause predators to misidentify them as inedible and/or inanimate bird droppings. However, the lack of a phylogeny for Phrynarachne impedes our understanding of the evolution of this trait in the genus.

Male spiders avoid sexual cannibalism with a catapult mechanism.

In the animal world, numerous mechanisms have been described that allow for extremely fast actions or reactions via the slow storage of energy, typically in elastic structures, which is then nearly instantly released, similar to the operation of a catapult. Many of these mechanisms are employed for prey capture or for predator avoidance; however, such superfast actions have not yet been reported as a means to dodge sexual cannibalism. Here, we unveil a novel mechanism in a communal orb-weaving spider Philoponella prominens (Uloboridae) (Figure S1), whereby males undertake a split-second catapult action immediately after mating, thereby fleeing their partner (Video S1).

Delimitation of the segmented trapdoor spider genus Luthela gen. nov., with comments on the genus Sinothela from northern China (Araneae, Mesothelae, Liphistiidae).

A new genus of the primitively segmented trapdoor spiders, which is endemic to the north of China, is described, Luthela gen. nov., and the status of Sinothela Haupt, 2003 and Sinothela sinensis (Bishop Crosby, 1932) is discussed and both are treated as nomina dubia.

Four new species of the primitively segmented spider genus Songthela (Mesothelae, Liphistiidae) from Chongqing Municipality, China.

This paper reports four new species of the primitively segmented spider genus Songthela from Chongqing Municipality, China, based on morphological characters of both males and females: S. jinyun sp. nov.

Male opportunistic mating increases with intensity of female sexual cannibalism in 3 web-building spiders.

Sexual conflict is common in animals, and female sexual cannibalism represents an extreme form of sexual conflict. Males in many species have evolved a variety of strategies to circumvent or decrease the risk of female sexual cannibalism. Opportunistic mating, by which a male mates with a female when she is disturbed or when she is feeding or undertaking moulting, is one of such kinds of strategies, and widely occurs in many animals, especially in spiders.

Conspicuous cruciform silk decorations deflect avian predator attacks.

Although camouflage as an effective antipredator defense strategy is widespread across animals, highly conspicuous color patterning is not uncommon either. Many orb-web spiders adorn their webs with extra bright white silk. These conspicuous decorations are hypothesized to deter predators by warning the presence of sticky webs, camouflaging spiders, acting as a decoy, or intimidating predators by their apparent size.

Four new species of the jumping spider genus (Araneae, Salticidae) from China.

We diagnose and describe four new species of Karsch, 1878 and describe for the first time the male of Peng, Li & Chen, 2003 from China based on morphological characters. The females of sp. nov.

Three new species of the primitively segmented spider genus (Araneae, Mesothelae) from Guizhou Province, China.

We diagnose and describe three new species of the primitively segmented spider genus from Guizhou Province, China, based on morphological characters and molecular data: (♂♀), (♂♀), and (♂♀). We provide the genetic distances within and among the three new species based on the DNA barcode gene, cytochrome c oxidase subunit I (COI) to support our descriptions. We also provide the COI GenBank accession codes for the three new species for future identification.

A new species of from Myanmar and description of the actual male of Thorell, 1897 (Araneae, Mesothelae, Liphistiidae).

Five Schiödte, 1849 species of the primitively segmented spider family Liphistiidae are currently known from Myanmar. Here, we described a new species, (♂♀), which was collected from Pyin Oo Lwin, Mandalay Region, Myanmar, diagnosed based on its genital morphology. The specimens (2♂♂, 5♀♀) collected by Walter C.

The complete mitochondrial genome of the intertidal spider (Desis jiaxiangi) provides novel insights into the adaptive evolution of the mitogenome and the evolution of spiders.

Background: Although almost all extant spider species live in terrestrial environments, a few species live fully submerged in freshwater or seawater. The intertidal spiders (genus Desis) built silk nests within coral crevices can survive submerged in high tides. The diving bell spider, Argyroneta aquatica, resides in a similar dynamic environment but exclusively in freshwater.

Three new species of the segmented spider genus (Mesothelae, Liphistiidae) from Hainan Island, China.

We report three new species of the segmented trapdoor spider genus Xu & Kuntner, 2015 collected from Hainan Island, China based on morphological characters: (♂♀), (♂♀), (♂♀). We also provide the GenBank accession codes of the DNA barcode gene, cytochrome c oxidase subunit I (COI), of the type specimens of all three new species to aid future identification.

Phylogenomic Analysis of Ultraconserved Elements Resolves the Evolutionary and Biogeographic History of Segmented Trapdoor Spiders.

The segmented trapdoor spiders (Liphistiidae) are the sole surviving family of the suborder Mesothelae, which forms the sister lineage to all other living spiders. Liphistiids have retained a number of plesiomorphic traits and their present-day distribution is limited to East and Southeast Asia. Studying this group has the potential to shed light on the deep evolutionary history of spiders, but the phylogeny and divergence times of the family have not been resolved with confidence.