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Synotaxus. A, B, S. monoceros male palp. Character numbers and states typeset in bold here and in subsequent captions. A, ventral; note spur on patella (arrow) (20-1). B, ectal. C, D, S. waiwai male palp. C, ventral. D, tarsal organ, with a small opening (198-0). E–G, Synotaxus waiwai, spinnerets. E, ALS. F, PLS and PMS; note large (214-1) but not flattened AGs (215-0, 216-0). G, CY, the fusule bears no distinct base (221-1). Scale bars: A–C, 100 µm; D–G, 10 µm.
Source publication
This paper offers the first cladistic analysis of a wide selection of theridiid genera based on morphological data. The analysis treats 53 theridiid taxa representing 32 genera (Achaearanea, Anelosimus, Ameridion, Argyrodes, Ariamnes, Carniella, Cerocida, Chrysso, Coleosoma, Dipoena, Emertonella, Enoplognatha, Episinus, Euryopis, Faiditus, Kochiura...
Citations
... Despite numerous taxonomic revisions at the subfamily or genus level, the systematics of theridiids remains unresolved. To date, specialized morphological or molecular phylogenies of theridiids (Agnarsson, 2004;Agnarsson Jinxin Liu and Yun Liang should be considered the joint first authors. species transfers based on morphological evidence, particularly concerning Dipoena, Euryopis, or related genera (Fitzgerald & Sirvid, 2003;Levi, 1954;Levi & Levi, 1962;Wunderlich, 1988;Yoshida, 2002). ...
... Despite numerous taxonomic revisions at the subfamily or genus level, the systematics of theridiids remains unresolved. To date, specialized morphological or molecular phylogenies of theridiids (Agnarsson, 2004;Agnarsson Jinxin Liu and Yun Liang should be considered the joint first authors. species transfers based on morphological evidence, particularly concerning Dipoena, Euryopis, or related genera (Fitzgerald & Sirvid, 2003;Levi, 1954;Levi & Levi, 1962;Wunderlich, 1988;Yoshida, 2002). ...
... As an effective method to resolving the affinities between groups that are difficult to identify, phylogeny has been widely applied to a diverse range of organisms. The study of theridiids has also embraced this methodology, leading to several phylogenetic hypotheses of theridiids based on morphological and/or molecular data (Agnarsson, 2004;Arnedo et al., 2004;Liu et al., 2016). However, nearly all studies mainly focused on exploring phylogenetic placement and phylogenetic relationships at the family or subfamily level (Bond et al., 2014;Dimitrov et al., 2017;Garrison et al., 2016;Kallal et al., 2020;Kuntner et al., 2019;Liu et al., 2016;Wheeler et al., 2017). ...
The cobweb spider subfamily Hadrotarsinae is generally regarded as the ant-eating group, consisting of 14 genera distributed
worldwide, with seven genera distributed in East Asia. This group has a long and complex taxonomic history and remains
under revision at the genus level. It is difficult to complete all the revision work in the short term because of the high species
diversity and wide distribution. In addition, the evolutionary history and affinities of Hadrotarsinae are poorly known due to
the lack of a stable phylogenetic hypothesis based on a wide taxon sampling. In recent years, although several morphological
and/or molecular phylogenetic studies have showed the monophyly of hadrotarsines and revealed their positions within
theridiid phylogeny, their internal evolutionary relationships remain unresolved due to limited taxon sampling within the
group. In this study, we present the first molecular phylogenetic analysis focused on East Asian hadrotarsines, using molecular
datasets of previous works as a backbone to explore phylogenetic relationships among these genera. Our results reveal that
two hadrotarsine species, Dipoena pelorosa Zhu, 1998, and Euryopis galeiforma Zhu, 1998, are distantly related to the main
East Asian hadrotarsine lineage, with the former forming a sister relationship to the lost colulus clade (Anelosiminae plus
Theridiinae) plus Phoroncidia, and the latter nested within Theridiinae. Meanwhile, the main lineage of hadrotarsines is
divided into five lineages, and the composition of the most lineages is associated with species from different genera. Based
on morphological characteristics and the principle of maintaining clade monophyly, we propose nine nomenclatural changes,
especially including a genus-level synonym, and all changes are as follows: Phycosoma submustelina (Zhu, 1998) comb.
nov., Phycosoma ripa (Zhu, 1998) comb. nov., Phycosoma turriceps (Schenkel, 1936) comb. nov., Lasaeola wangi (Zhu,
1998) comb. nov., Lasaeola complexa (Gao & Li, 2014) comb. nov., and Yaginumena Yoshida, 2002 syn. nov. (= Lasaeola
Simon, 1881), coincided with the transfer of all known Yaginumena species to Lasaeola. Furthermore, our dating analysis
places the crown age of the hadrotarsines in the early Eocene.
... All measurements are in millimetres (mm). Terminology in the present paper follows Agnarsson et al. (2007) and Liu et al. (2022). The abbreviations used in the text and figures are: At -atrium, AME − anterior median eye, ALE − anterior lateral eye, C -conductor, CD − copulatory duct, E -embolus, FD − fertilisation duct, MA − median apophysis, MS − medium septum, PLE − posterior lateral eye, PME − posterior median eye, S -spermatheca, St -subtegulum, STL − sternum length, STW − sternum width, T -tegulum, TTA − theridiid tegular apophysis. ...
... Both morphological and phylogenetic evidence have suggested that Episinus is a member of the subfamily SpintharinaeSimon, 1894(Arnedo et al. 2004, Agnarsson 2004Durán-Barrón et al. 2013 ...
Background
Currently, the genus Episinus Walckenaer, 1809 includes 64 described species mainly being distributed in Asia, Africa and the Americas, with 16 described species in China. During the recent surveys across various regions of China, we found three previously undescribed species which have been identified as belonging to Episinus.
New information
Three new species of Episinus Walckenaer, 1809 are described: Episinus anfu sp. nov. (♀) from Jiangxi Province, E. implicatus sp. nov. (♀) from Yunnan Province and E. pseudonubilus sp. nov. (♂♀) from Shaanxi Province. Based on morphological characteristics and previous studies, we further propose five species groups to accommodate the Chinese Episinus, including two species groups proposed by Liu et al. (2022). Detailed descriptions, photographs, hand drawings, DNA barcodes and a distribution map of the three new species are provided.
... They write: "the abdominal shape and genitalic structure (in particular that of the male palp) place it closer to Rhomphaea. The arrangement of the primary sclerites (embolus, conductor, median apophysis, theridiid tegular apophysis) of the male palp of Rhomphaea (Agnarsson 2004) is similar to that of the Hawaiian Ariamnes." On the base of unpublished DNA sequences they state (p. ...
The spider genus Ariamnes
... Legs measurements are given as total length (femur, patella, tibia, metatarsus, tarsus). The terminologies used in figure legends follow Agnarsson (2004) and Agnarsson et al. (2007). All measurements were in millimeters (mm). ...
Four Yunohamella species are reported from Hubei Province, China, including two new species: Y. gutenbergi R. Zhong, J. Liu & Hu, sp. nov. (♂) and Y. mohorovicici R. Zhong, J. Liu & Hu, sp. nov. (♂). Yunohamella jiugongensis (Liu & Zhong, 2023), comb. nov. is transferred from the genus Cryptachaea Archer, 1946, and Y. lyrica (Walckenaer, 1841) is newly recorded from Hubei Province and is considered as a senior synonym of Platnickina mneon (Bösenberg & Strand, 1906).
... They write: "the abdominal shape and genitalic structure (in particular that of the male palp) place it closer to Rhomphaea. The arrangement of the primary sclerites (embolus, conductor, median apophysis, theridiid tegular apophysis) of the male palp of Rhomphaea (Agnarsson 2004) is similar to that of the Hawaiian Ariamnes." On the base of unpublished DNA sequences they state (p. ...
... Body length was considered as total length of prosoma + total length of opisthosoma (excluding spinnerets). A description of morphological terminology follows Agnarsson (2004). All measurements are in millimetres. ...
Long-legged Theridiidae of the genus Meotipa Simon, 1895, characterized by distinctive flattened black spines on the abdomen and legs, are commonly found in the foliage of tropical rainforests across the Oriental region, including Sri Lanka and China. In this work, we describe three new species: Meotipa sujii Benjamin & Tharmarajan sp. nov. (♂♀), Meotipa kudawaensis
Benjamin & Tharmarajan sp. nov. (♀), both endemic to Sri Lanka, and Meotipa wuzhishanensis Benjamin sp. nov. (♂♀) found only in China. These species align with the diagnostic characters provided by Deeleman-Reinhold (2009), supporting the distinct status of Meotipa from Chrysso O. Pickard-Cambridge, 1882. Notably, the spiniventris-group, marked by black spines on the abdomen and/or legs, appears morphologically distinct from larger-bodied Meotipa species, with potential differentiation in genital structures.
... However, the subfamily affiliation of some theridiid genera remained uncertain; and we preferred to listing herein, e.g., Phoroncidia Westwood, 1835 in old Simon's (1894) tribe Phoroncidini. Hadrotarsines were formerly described as an independent family and listed in Haplogynae (see discussions in Forster et al. 1990 andAgnarsson 2004), but today they are recognized as a theridiid subfamily. O. Pickard-Cambridge, 1894 (Agnarsson 2004: figs 24C, 31G, 69E, and 74D, respectively), and Knoflachia Eskov 2024: fig. ...
... Agnarsson (2004: 462) united Pholcomma, Carniella, and Robertus in 'clade 35', and agreed with Knoflach's (1996) (Agnarsson 2004: 463). Bothrial morphology clearly confirms the particular position of the well-supported Agnarsson's (2004) 'clade 35' in the family Theridiidae. It should be mentioned that according to some molecular data (Arnedo et al. 2004) Pholcomma and Robertus were considered as the sister group to the remaining theridiids. ...
... It should be mentioned that according to some molecular data (Arnedo et al. 2004) Pholcomma and Robertus were considered as the sister group to the remaining theridiids. Thus, we propose to assign to the Agnarsson's (2004) 'clade 35', comprising the four genera of habitually similar small/minute 'erigonid-like theridiids', i.e., Theonoe, Carniella, Robertus, and Pholcomma, the rank of a separate subfamily of Theridiidae. When choosing the name for this taxon, comprising both Theonoe and Pholcomma, the Theonoeinae Simon, 1894, stat. ...
Bothrial morphology was studied by SEM in 137 araneoid genera representing all 22 currently recognized extant families and all 42 conventional subfamilies of the Araneoidea. The ancestral type in the superfamily Araneoidea is a ‘hooded’ bothrium with a single well-developed transverse ridge, dividing its proximal and distal plates (‘Erigone-type’); the advanced type is a solid dome-like bothrium without vestiges of the ridge (‘Theridion-type’); there are several intermediate types reflecting various pathways and stages of the ridge reduction (united here as ‘Argiope-type’). The parallel trends in bothrial evolution, recognized as continuous series from the ancestral type up to the advanced one through some intermediate stages, are distinguished in each of the seven main phylogenetic lineages of the superfamily: ‘tetragnathoids’, ‘araneoids’, ‘cyatholipoids’, and ‘theridioids’ possess a complete set of the three types, while ‘malkariods’, ‘symphytognathoids’. and ‘linyphioids’ lack the advanced, dome-like type (‘Theridion-type’). Only three taxa have been proposed earlier as the sister group of the superfamily Araneoidea: Nicodamoidea, Deinopoidea, and Leptonetoidea; morphology of bothria, as well as other cuticular microstructures, clearly supports the araneoid-nicodamoid relationship hypothesis, purely ‘molecular’ to date. Bothrial morphology provides the additional arguments for several taxonomic acts, e.g., for the reranking the Agnarsson’s (2004) ‘clade 35’ (Theonoe, Carniella, Robertus, and Pholcomma) up to the Theonoeinae Simon, 1894, stat. nov., and for the revalidation the micropholcommatid Plectochetos Butler, 1932, gen. revalid. and zygiellid Parazygiella Wunderlich, 2004, gen. revalid.
... This genus has been previously known from Baja California Sur, Hidalgo, Jalisco, Nuevo León, and San Luis Potosí in Mexico (Exline & Levi 1962, Jiménez et Diagnosis: The genus Ariamnes is characterized by its elongated, vermiform opisthosoma, and epiandrus gland spigots which are not in sockets. Males usually possess modified prosomas and emboli with a terminal apophyses, while females have elongated spermathecae (Exline & Levi 1962, Agnarsson 2004, Martínez-Sánchez & Chamé-Vázquez 2019. ...
... Species of Synotaxus are characterized by a mostly green body, long, fragile legs and a slender, posteriorly elongated abdomen (Exline & Levi 1965). They are known as arboreal spiders, building a vertical ladder-like tangle web (also referred to as "chicken-wire shaped web") between leaves and branches of bushes (Eberhard 1977(Eberhard , 1995(Eberhard , 2022Agnarsson 2003Agnarsson , 2004 (Ramírez et al. 2022). Among them, Gaucelmus is a troglophilic genus whose members weave scaffold webs on walls and ceilings of caves and other shaded environments (Gertsch 1984;Reeves 1999;Eberhard et al. 2008). ...
The unique foraging ecology of the synotaxid spider Tekellina sadamotoi, including its natural diet and predatory behavior, is described based on field observations and laboratory experiments. Three-year field observations revealed that the natural diet of T. sadamotoi primarily consisted of a psocodea species, Paracaecilius japanus, which accounted for 98% of the prey items. In the field, the spider’s behaviour during prey capture was characterized by the absence of wrapping silks, and the biting site being the mouthparts of the prey. There was no significant positive correlation between prey and predator sizes, as even small juveniles were capable of consuming large prey. Laboratory experiments revealed that the predatory sequences of T. sadamotoi consisted of four behavioral elements: pre-strike, strike, lifting, and consumption. During the initial bite at the strike, the spider targeted various parts of the prey, including the dorsum of the prey’s thorax, forewings, or abdomen, later relocating the biting site to the prey’s mouthparts during consumption phase. The use of silk wrapping was not observed during predatory sequences, as suggested by the field observations. The study further discusses the relationship between the unique foraging ecology of T. sadamotoi and the unusual
spinneret morphology of the genus, proposing implications for psocoptera pecialist, which had not been detected among spiders before.
... Differences are possibly due to a sampling bias from the methods used [29]. Night collections involve active searches for spiders in all vegetative strata and thus were more likely to result in a higher abundance of spiders caught in middle and high vegetative strata than in pitfall traps ( Figure 4) [7,[29][30][31][32]. The most abundant species collected generally belonged to the most abundant families found (Figure 4). ...
Spiders have important ecological roles as generalist predators, are a significant source of food for many other species, and are bioindicators of environmental health. However, spiders are poorly studied. Given their importance, a comparison of spider survey methods used to determine differences in spider diversity and abundance is required to understand their limitations and biases. A new survey method to attract spiders, based on vibration from an idling diesel tractor, was tested and compared to the traditional methods of pitfall trapping and hand collection of spiders at night. Across the three survey methods, there were, in total, 2294 spiders in 34 families, 138 genera, and 226 species identified. Spider species diversity and richness were significantly greater for spiders collected at night than from the other two methods (spiders collected in pitfall traps and attracted to vibration). The collection of spiders using the night collection and vibration-based methods were very similar in terms of labor required and material costs. Of all spider species identified, 80% were captured during hand collection, 30% through pitfall trapping, and 30% from vibration-based collection. Most species of spiders caught in pitfall traps were species known to be primarily ground-dwelling, whereas both arboreal and ground-dwelling spiders were collected at night and as a result of being attracted and collected using the vibration-based method.
