Palpal Bulb Research Articles

Hidden in the plains: Two new extra‐andean species of Euathlus (Mygalomorphae, Theraphosidae) from Argentina with comments on their sexual behaviour

AbstractTwo new species of Euathlus (Verhandlungen der Kaiserlich‐Königlichen Zoologisch‐Botanischen Gesellschaft in Wien, 1875, 25, 125) from Argentina are described. Euathlus ameghinoi sp. n. and Euathlus ventus sp. n. are the first records for the Patagonian Steppe. Here we used mitochondrial DNA (cox1) to perform the first molecular phylogeny of some representatives of the genus. In addition, we present the first description of the sexual behaviour of the genus. Both molecular and cladistic morphological analysis showed the genus Euathlus as monophyletic, and new species were recovered as sister groups. New species show new morphological variations of typical characters for the genus (e.g. tibial apophyses and palpal organs).

A new species of Thrixopelma (Araneae: Theraphosidae: Theraphosinae) from southern Peru

ABSTRACT This work aims to describe a new species of Thrixopelma Schmidt, 1994 from southcentral Peru in the Department of Cusco. Thrixopelma choquequirao sp. nov. can be easily distinguished from congeneric species by the low number of labial cuspules, a very long palpal tibia, morphology of the male palpal bulb and female spermathecae. Currently the genus Thrixopelma comprises seven formally described species which inhabit Perú and Ecuador, distributed in Amazonian rainforest, Coastal Dry Forest, and Andean Dry Forest.

Jambu, a new genus of tarantula from Brazil (Araneae, Theraphosidae, Theraphosinae)

The genus Jambu gen. nov. is proposed based on two new species: Jambu paru gen. et sp. nov. and Jambu manoa gen. et sp. nov. Hapalopus butantan is transferred to Jambu; consequently, Jambu butantan gen. et comb. nov. is proposed. The geographic distribution of J. butantan is extended on the basis of new material collected. The new genus and the new species are here diagnosed, described and illustrated. The shape of the genitalia of Jambu resembles that of Hapalopini but differs from most of them by the presence of type IV urticating setae. The presence of this type of urticating setae allows us to hypothesize that this new genus is phylogenetically related with Grammostolini. Males of Jambu differ from those of other genera of Grammostolini by the presence of a paraembolic apophysis on the palpal bulb. Females also differ from those of other Grammostolini by the spermathecae morphology, with one medial lamp-shaped or heart-shaped receptacle. The homology of some features and the taxonomic placement of the new genus are discussed.

On the Identity of Neostenotarsus guianensis (Caporiacco, 1954), with a Redescription of the Holotype Male and the First Records from Guyana (Araneae: Theraphosidae)

Herein, we redescribe Neostenotarsus guianensis (Caporiacco, 1954) nearly seven decades after its original description. In the original description of Neostenotarsus scissistylus Tesmoingt & Schmidt, 2002, we found characters incongruent with N. guianensis, namely, the purported presence of serration on the prolateral keels of the palpal bulb; a narrower apical third of the embolus; the absence of a patch of bristles on the retrolateral face of the palpal tibia and of a baso-retrolateral protuberance on metatarsus I; and a shorter and more apically situated megaspine on the retrolateral branch of the tibial apophyses. The characters from its original description are discussed. N. scissistylus stat. rev. has been revalidated until such time as the type material, or topotypic material, can be examined by future workers.

On Psalmopoeus Pocock, 1895 (Araneae, Theraphosidae) species and tarantula conservation in Ecuador.

Two novel species of Psalmopoeus Pocock, 1895 are described from the north-western and central-western slopes of the Cordillera Occidental of the Andes mountain range in Ecuador. The new species are easily differentiated from other congeners of Psalmopoeus by spermathecae and male palpal bulb morphology and a comparatively distant distribution to the type localities of the geographically nearest known congeners. The diagnosis of P.ecclesiasticus Pocock, 1093 is revised and updated, considering the novel species and observations on spermatheca of this species. Likewise, an evaluation is provided for the new species in terms of conservation due to the various threats impacting ecosystems and ecosystem services of their type localities. Finally, the importance of theraphosid spiders in Ecuador and South America and their possible conservation requirements are discussed and assessed.

Revision of the Peruvian tarantula Homoeomma peruvianum (Chamberlin, 1916): description of a new genus with eleven new species and insights to the evolution of montane tarantulas (Araneae: Theraphosidae: Theraphosinae)

ABSTRACT The Peruvian tarantula Homoeomma peruvianum (Chamberlin, 1916) is revised. As the type specimens do not fit the diagnostic characters of Homoeomma Ausserer, 1871, especially because of the different palpal bulb morphology in males and the shape of spermathecae in females, H. peruvianum (Chamberlin, 1916) was transferred into the newly established genus Urupelma gen. n., which is herein described, diagnosed and illustrated. Eleven new species of Urupelma gen. n. (U. sanctitheresae sp. n., U. sanctimariae sp. n., U. awanqay sp. n., U. ashaninka sp. n., U. atarraz sp. n., U. megantonianum sp. n., U. machiguenga sp. n., U. pampas sp. n., U. johannae sp. n., U. veronicae sp. n., and U. dianae sp. n.) are herein described, diagnosed and illustrated. The monophyly of Urupelma gen. n. is supported by a molecular phylogenetic analysis focused on the tarantulas with urticating setae of type III and III+IV and based on three genes: the nuclear 18S and 28S, and the mitochondrial COI gene. Apart from the support of the new genus and some existing valid genera, the molecular phylogeny also sheds light on the dynamic evolutionary history behind the adaption to high montane environments in tarantulas.

Increasing knowledge of Cymbiapophysa Gabriel & Sherwood, 2020 (Araneae, Theraphosidae): general distribution, key to species, and three new species from Ecuador.

Three new species of Cymbiapophysa Gabriel & Sherwood, 2020 are described from south, central, and north-western Ecuador, showing the wide range of distribution that this genus has in Ecuador and its biogeographical provinces. These three new species are easily differentiated from other congeners based on keel morphology of the male palpal bulb. Supplementary information about the locality of C.magna Sherwood, Gabriel, Brescovit & Lucas, 2021 is provided, alongside additional data on morphology and some commentaries about the general distribution and biogeography of Cymbiapophysa. Additionally, a taxonomic key for males of Cymbiapophysa species is presented, based on the palpal bulb morphology.

Three new and exceptional Damarchus species from Thailand (Araneae: Bemmeridae)

Damarchus pylorus sp. nov., D. lanna sp. nov. and D. dao sp. nov. are described from males and females collected in western and northern Thailand. Damarchus pylorus sp. nov. and D. lanna sp. nov. are morphologically unique within the genus by males having a para-embolic apophysis and a keel composed of coarse laminae on the lower (posterior) side of the palpal organ, and by females having sperm receptacles, composed of a strongly sclerotized base and an unsclerotized head, situated on the ventral side of a relatively long genital atrium. The distantly related D. dao sp. nov. is distinguished from all other congeners by males having a tibia I coupling spur with three megaspines. Presumed relationships of these three species and of the genus Damarchus are discussed. Information on biology and burrow structures of the new species is provided. Damarchus pylorus sp. nov. stands out by plugging the side shaft of its burrow with a soil pellet; similar plugging devices in unbranched burrows are known from other spider families.

A new species of Linothele Karsch, 1879 (Araneae: Dipluridae) from south-eastern Ecuador

We describe a new species of Linothele Karsch, 1879 from the south-eastern slopes of the Andes in Ecuador. The new species can be distinguished from all congeners by the presence of abundant bright whitish-golden curly setae on the carapace; a patternless grey abdomen in adults, with short whitish-golden setae, short black setae and long and erected black setae, and lacking maculae; the elongate and apically tapered spermatheca with 3–5 elongated vesicles placed medially; the prominent metatarsal tubercle and tibial megaspine in leg I in the male, and the male palpal bulb longer than wide, with flattened apical part of the embolus. We comment on the bulb morphology and ontogenetic colour variation of Linothele and discuss the distribution of some Linothele from the eastern Andes and Amazonian lowlands.

The First Record of Ero aphana (Araneae: Mimetidae) in Egypt

Sawers, M.A.R., S.M.O. El-Bishlawy, M.F. Hassan and G.M.S. Sallam. 2023. The First Record of Ero aphana (Araneae: Mimetidae) in Egypt. Arab Journal of Plant Protection, 41(1): 15-17. https://doi.org/10.22268/AJPP-41.1.015017 This investigation presents a new record, Ero aphana (Walckenaer, 1802) (Araneae: Mimetidae) in the Egyptian fauna. It was found in the Experimental Station of the Faculty of Agriculture, Cairo University, Giza Governorate, Egypt on grapefruit trees (Citrus paradise) on October 1, 2018. Six Specimens; one male and five Juveniles of E. aphana were collected and identified. In addition, notes on the description, environmental conditions and collection data of this species are given. Photos of general habitus and palpal organ of the male and measurements of leg segments are illustrated. Keywords: Araneae, Mimetidae, Ero aphana, new record, Egypt

A new tarantula (Mygalomorphae: Theraphosidae) genus endemic from Peru with a novel genitalic morphology among theraphosinae and its phylogenetic placement

Chinchaysuyu gen. nov. is described as a new monotypic Theraphosidae genus from northern Peru, with distinct genitalic morphology. Males of Chinchaysuyu gen. nov. differ from all known species by having a palpal bulb organ with many conspicuous keels extending towards the subtegulum. Females differ by having two pairs of short and hyper-sclerotized receptacles. This new genus is described and illustrated on the basis of the type species Chinchaysuyu spinosa sp. nov. and their morphological affinities and its phylogenetic position are analyzed and discussed.

Evolutionary morphology of sperm in pholcid spiders (Pholcidae, Synspermiata).

Pholcidae represent one of the largest and most diverse spider families and have been subject to various studies regarding behavior and reproductive biology. In contrast to the solid knowledge on phylogeny and general reproductive morphology, the primary male reproductive system is strongly understudied, as it has been addressed only for few species. Those studies however suggested a high diversity of sperm and seminal secretions across the family. To address this disparity and reconstruct the evolution of sperm traits, we investigate the primary male reproductive system of pholcid spiders by means of light, X-ray, and transmission electron microscopy using a comprehensive taxon sampling with 46 species from 33 genera, representing all five subfamilies. Our data show a high disparity of sperm morphology and seminal secretions within pholcids. We document several sperm characters that are unique for pholcids, such as a helical band (Pholcinae) or a lamellate posterior centriolar adjunct material (Modisiminae). Character mapping revealed several putative synapomorphies for individual taxa. With regard to sperm transfer forms, we found that synspermia occur only in the subfamily Ninetinae, whereas the other subfamilies have cleistospermia. In several species with cleistospermia, we demonstrate that spermatids remain fused until late stages of spermiogenesis before ultimately separating shortly before the coiling process. Additionally, we explored the previously hypothesized correlation between sperm size and minimum diameter of the spermophor in the male palpal organ. We show that synspermia differ strongly in size whereas cleistospermia are rather uniform, but neither transfer form is positively correlated with the diameter of the spermophor. Our data revealed a dynamic evolution of sperm characters, with convergences across all subfamilies and a high level of homoplasy. The present diversity can be related to subfamily level and allows for assignments of specific subtypes of spermatozoa. Our observations support the idea that Ninetinae are an ancestral clade within Pholcidae that have retained synspermia and that synspermia represent the ancestral sperm transfer form of Pholcidae.

Spider Origins: a Palaeontological Perspective

Spiders (Araneae) can be placed within a series of nested clades within Arachnida. Arachnopulmonata encompasses all arachnids with book lungs. Pantetrapulmonata encompasses arachnids with four pairs of lungs in their ground pattern. Tetrapulmonata potentially encompasses pantetrapulmonate arachnids which have reduced the number of lateral eye lenses and endites on the coxae of the first pair of walking legs. Serikodiastida encompasses arachnids with opisthosomal silk glands. Several spider-like fossils, some of which were previously interpreted as spiders, may belong either here or in the wider tetrapulmonate group. Araneida encompasses arachnids with spinnerets and a male palpal organ, and fossils reveal that the common ancestor of spiders would have retained a flagelliform telson. Araneae can thus be defined as spiders which have lost the telson, something which appears to have occurred multiple times among arachnids. The oldest fossil example of each of these clades is documented, and compared to molecular estimates of origination dates where available, to yield a broad temporal and phylogenetic framework for spider origins.

Thrixopelma nadineae, a New Theraphosine from Ecuador (Araneae: Theraphosidae)

Thrixopelma nadineae sp. nov. is described from Loja, Ecuador, based on the male, which possesses distinctive palpal bulb, metatarsal and tibial apophysis morphology. The new species represents the second species of Thrixopelma to be recorded from Ecuador.

First record of Tmesiphantes Simon, 1892 (Araneae, Theraphosidae) in Peru: a new species and its phylogenetic placement.

The tarantula genus Tmesiphantes Simon, 1892 includes 20 valid species distributed in Argentina and Brazil. These spiders are distinguished from other Theraphosinae genera by the presence of an incrassate femur III, more evident in males, urticating hair types III and IV on the abdominal dorsum, few cuspules on the labium (0 to 30), maxillae with a maximum of 200 cuspules and sternum rounded. From recent examination of material from Peru, we discovered specimens that share all the morphological characters of Tmesiphantes, but did not fit with any known species. In the present study T. intiyaykuy sp. nov. is diagnosed, described, and illustrated. This new species resembles T. caymmii in the circular patch with stiff setae on midventral abdomen but can be distinguished by the shape of the palpal bulb and spermathecae. Also, we performed a phylogenetic analysis using morphological characters to infer the taxonomic placement of the new species. The analysis included 26 terminal species and 36 characters. Representatives of Tmesiphantes formed a monophyletic group and T. intiyaykuy sp. nov. is close related with T. caymmii. A dichotomous identification key and a geographic distribution map were constructed for recognized species of Tmesiphantes.

Redescription of the theraphosine Hapalotremus albipes Simon, 1903 and description of four new species of Hapalotremus Simon, 1903 from Peru and Bolivia (Araneae: Theraphosidae)

The holotype of Hapalotremus albipes Simon, 1903 is redescribed. Four new species of the genus Hapalotremus Simon, 1903 are described: Hapalotremus apasanka sp. nov., Hapalotremus hananqheswa sp. nov., and Hapalotremus kaderkai sp. nov. from Peru, and Hapalotremus yuraqchanka sp. nov. from Bolivia. Discussion on palpal bulb morphology, ontogenetic spermathecal morphology, and biogeography is presented. Historical information about collectors and comments on the accession numbers and other label information of historical specimens is also presented.

A new species of Cymbiapophysa Gabriel & Sherwood, 2020 from Colombia and a transfer from Proshapalopus Mello-Leitão, 1923 (Araneae: Theraphosidae)

A new species of CymbiapophysaGabriel & Sherwood, 2020, C. magnasp. nov. is described from Colombia. Proshapalopus marimbaiPerafán & Valencia-Cuéllar, 2018 is transferred to Cymbiapophysa from ProshapalopusMello-Leitão, 1923, based on male palpal bulb and tibial apophysis morphology, female spermathecal morphology, comparative labial cuspule counts in both sexes, and biogeography, creating the new combination Cymbiapophysa marimbaicomb. nov. Aspects of some structures of the male palpal bulb are also discussed.

Stabilizing a chaotic taxonomy: redescription and redefinition of the genera Lasiodorides Schmidt & Bischoff, 1997 and Thrixopelma Schmidt, 1994 (Araneae: Theraphosidae)

The genera LasiodoridesSchmidt & Bischoff, 1997 and Thrixopelma Schmidt, 1994 are preliminarily revised, and their taxonomy stabilized. Both sexes of Lasiodorides polycuspulatusSchmidt & Bischoff, 1997, and the male of Lasiodorides striatus (Schmidt & Antonelli, 1996) are redescribed, and the genus Lasiodorides is rediagnosed. Lasiodorides rolinaeTesmoingt, 1999 is proposed as a junior synonym of L. polycuspulatussyn. nov., based on colouration and spermathecal morphology. Lasiodorides remotus Schmidt, 2007 is proposed as a junior synonym of L. polycuspulatussyn. nov., based on spermathecal morphology. Thrixopelma aymara (Chamberlin, 1916) and Thrixopelma lagunasSchmidt & Rudloff, 2010 are redescribed. Thrixopelma ockerti Schmidt, 1994 is illustrated from the syntype series and redescribed based on a non-type female from Iquitos, Peru, held in the collections of the Museo de Historia Natural, Universidad Nacional Mayor de San Marcos, Lima, Peru. Thrixopelma longicolli (Schmidt, 2003) comb. nov. is newly transferred from Lasiodorides to Thrixopelma based on palpal bulb morphology, and the holotype male is redescribed. The inherent problems of the paratype exuviae of this taxon are also discussed. Thrixopelma peruvianum (Schmidt, 2007) comb. nov. is newly transferred from EuathlusAusserer, 1875 following examination of the holotype female exuvia and a conspecific non-type female exuvia. Thrixopelma cyaneolum Schmidt, Friebolin & Friebolin, 2005 is discussed ad illustrated from the syntype female exuviae. Thrixopelma pruriensSchmidt, 1998 is discussed and illustrated from the holotype female exuvia, and the problematic non-type material discussed. Finally, we argue that future designation of exuviae as type specimens of novel theraphosid spiders should be considered an unacceptable practice in arachnology.

First record of the tarantula genus Bumba (Araneae: Theraphosidae) from Bolivia, with the description of a new species

ABSTRACT A new species of Bumba Perez-Miles, Bonaldo & Miglio, 2014 is described and illustrated. This species comprises the first record of the genus for Bolivia. Bumba paunaka sp. nov. differs from the other species in the genus in the black longitudinal band on abdomen, in the long and slender embolus of the palpal bulb and in the thin and long subapical spine of the retrolateral branch of tibial apophysis. Females additionally differ in the spermathecal morphology. Finally, a distribution map for all known species of Bumba is presented.

A new species of Umbyquyra Gargiulo, Brescovit & Lucas, 2018 from Goiás, Brazil (Araneae: Theraphosidae)

A new species of Umbyquyra Gargiulo, Brescovit & Lucas, 2018, Umbyquyra gurleyisp. nov., is described from Goias, Brazil, based on distinctive palpal bulb morphology.