Cheliceral Dentition Research Articles

Three new species of Amblyseius Berlese (Mesostigmata: Phytoseiidae) from Altai Republic, Russia

Three new species of predatory mites belonging to the genus Amblyseius Berlese (Acari: Phytoseiidae), A. latisetosus sp. nov., A. unodentatus sp. nov., and A. altaiensis sp. nov. are described based on the material collected from Altai Republic, Russia. The new species are assigned to the obtusus species group and andersoni species subgroup by having setae J2 and Z1, short and minute setae z4, sub-pentagonal ventrianal shield, and bell-shaped calyx of spermatheca. All new species were compared with each other and all other Amblyseius species known to date. The main diagnostic characters of these species are measurements of prominent dorsal setae, ventral setae JV5 and macrosetae on leg IV, cheliceral dentition, number of setae on genu II as well as small rounded and distinct pre-anal pores on ventrianal shield.

On the taxonomy of the jumping spider genus Matinta Ruiz & Maddison, 2019, with a taxonomic revision of the vicana species-group (Araneae: Salticidae: Amycini).

The male of Matinta opiparis (Simon, 1900) is redescribed based on fresh material, and the female is described for the first time. Matinta tatianae sp. nov. (male) is described from Acre and Par, Brazil. The vicana species-group of Matinta is revised, as follows: the males of M. silvae (Crane, 1943), M. fonsecai (Soares & Camargo, 1948), and M. vicana (Simon, 1900), and the female of M. silvae are redescribed based on fresh material. Three new species of the group are described: Matinta maddisoni sp. nov. from Morona Santiago, Ecuador (); Matinta pereirae sp. nov. from Amazonas, Brazil (); and Matinta aragog sp. nov. from French Guiana (). Detailed description of cheliceral dentition is given and commented. We conclude that the complex dentition within Amycini should be revised and more carefully studied.

Three new troglobitic species of Pseudochthonius Balzan, 1892 (Pseudoscorpiones, Chthoniidae) from northeastern Brazil.

Three new pseudoscorpion species, Pseudochthonius pali sp. nov., Pseudochthonius diamachi sp. nov., and Pseudochthonius koinopoliteia sp. nov., are herein described from caves of Bahia state, Brazil. They can be distinguished from congeners mainly by the absence of eyes or eyespots, chelal and cheliceral dentition, coxal chaetotaxy and body size. Some ecological remarks on each species, possible threats, recommendations for future research and a key to the Pseudochthonius species from Brazil are provided.

New records and complementary descriptions of three Phytoseiidae (Acari: Mesostigmata) species from Turkey

ABSTRACT Three species of the family Phytoseiidae (Acari: Mesostigmata), Amblydromalus limonicus (Garman and McGregor), Neoseiulus fauveli (Athias-Henriot), and Typhlodromips sessor (De Leon), are reported for the first time from Turkey. The newly recorded species are redescribed and illustrated based on material collected from poplar trees, Populus spp. (Salicaceae), in Samsun Province on the Black Sea coast. Amblydromalus limonicus and T. sessor are mainly known from the Americas and are unexpected findings on poplar trees, as well as in the Turkish fauna. The third species, Neoseiulus fauveli, is known only from its original description from France. However, important morphological features, including dorsal setae lengths, cheliceral dentition, measurements, and the shape of macrosetae on legs, that are currently used to discriminate phytoseiid species, were missing in its original description. The presence of N. fauveli on Populus nigra L. in the present study is not surprising as many other species in the desertus species group of the genus Neoseiulus have been reported from species of Populus.

Brief Inventory of Phytoseiidae (Parasitiformes) Found on Vegetable Crops in the Republic of Congo

According to the last revised catalogue of the mite family Phytoseiidae and the online Phytoseiidae database, only six species of predatory mites have been identified to date in the Republic of Congo (RC). Two species were reported on cassava (Manihot esculenta), two on coffee (Coffea spp.), one on lemon (Citrus spp.), and one on unidentified plants. In this study, we catalogued predatory mites on five plants of economic interest in the RC. Two hundred and forty-seven mite specimens were collected on Manihot esculenta, Solanum lycopersicum, Solanum melongena, Abelmoschus esculentus, and Capsicum spp. Traditional taxonomy was used to identify the collected specimens. The morphological characteristics of the females were analyzed, including the lengths of the dorsal setae, presence or absence of dorsal and ventrianal setae, shape of insemination apparatus, leg chaetotaxy, and cheliceral dentition. Six species belonging to two subfamilies (Phytoseiinae and Amblyseiinae) and five genera (Amblyseius, Euseius, Paraphytoseius, Phytoseius, and Iphiseius) were identified. Among these six species, only one had previously been observed in the RC; the remaining five species are reported.

The genus Eurytromma from Sri Lanka: the homology of penial macrosetae in Podoctidae matches the gonyleptoid AE11 pattern (Opiliones: Laniatores: Epedanoidea)

A description of the pattern of structure and organization of the penial macrosetae was recently put forward for Gonyleptoidea Sundevall, 1833 and demonstrated to occur also in other families of Grassatores Kury, 2002, such as Assamiidae Sørensen, 1884, Epedanidae Sørensen, 1886 and Pyramidopidae Sharma, Prieto & Giribet, 2011. This set of homology hypotheses is herein called AE11 pattern. In this work, the monotypic Sri Lankan genus Eurytromma Roewer, 1949 of the family Podoctidae Roewer, 1912 (which is currently assigned to the Epedanoidea in the Grassatores) is studied. Male genitalia of Eurytromma are described for the first time and the first attempt is made to reconcile the chaetotaxy of ventral plate of podoctid species with the AE11 pattern. The podoctid genera Hoplodino Roewer, 1915, Strandibalonius Roewer, 1912 and Santobius Roewer, 1949 are also exemplified here; their set of macrosetae is described and the AE11 pattern is demonstrated to occur in all of them. Therefore, AE11 is more phylogenetically widespread in the Grassatores than previously thought. Eurytromma pictulum (Pocock, 1903) from Sri Lanka is redescribed. It is characterized by the presence of a meso-frontal stridulatory saw of denticles on the cheliceral hand and extreme reduction of mesotergal sutures. A further refinement is made on the current terminology system of cheliceral dentition of Podoctidae.

Thunberga gen. nov., a new genus of huntsman spiders from Madagascar <br />(Araneae: Sparassidae: Heteropodinae)

A new genus of the family Sparassidae is described from Madagascar: Thunberga gen. nov. It can be distinguished from other genera of the Heteropodinae by its different cheliceral dentition and eye arrangement as well as by its uniquely dotted prosoma. Four species are transferred to the new genus: T. hildebrandti (Järvi, 1912) comb. nov. (from Rhitymna Simon, 1897a), T. malagassa (Strand, 1907) comb. nov. (from Olios Walckenaer, 1837), T. nossibeensis (Strand, 1907) comb. nov. (from Olios), T. septifer (Strand. 1908) comb. nov. (from Olios, elevated to species rank). T. hildebrandti comb. nov. is recognised as junior synonym of T. nossibeensis comb. nov. One species is described for the first time: Thunberga greta spec. nov. (female, Madagascar). The systematic placement within the family and the character "anterior epigynal pocket" are discussed.

Gnathopalystesaureolus (He & Hu, 2000): new combination for Pseudopodaaureola (Araneae, Sparassidae), with the first description of the female from Hainan Island, China.

The taxonomic status of Pseudopodaaureola (He & Hu, 2000) is revised based on the re-examination of the type specimen and fresh material collected from the type locality. The cheliceral dentition, with a large denticle field between two anterior and three posterior teeth, the male palps with simple RTA arising distally, narrow, not filiform embolus and sheet-like membranous conductor, and the female epigyne with a visible median septum indicate that the species does not belong to Pseudopoda or to the originally assigned genus, Heteropoda. Based on these characters, the species is here transferred to Gnathopalystes. The male is redescribed and the female is described and illustrated for the first time.

Allogynaspis flechtmanni, a new genus and species of the subfamilyMacrochelinae (Acari: Mesostigmata: Macrochelidae) from southeastern Brazil, with comments on cheliceral dentition, reproductive strategies, and postepigynal platelets.

Allogynaspis flechtmanni n. gen., n. sp. is described from litter bordering a stream in a forested area of Itatiaia National Park in southeastern Brazil. Although it shares a number of traits with the free-living macrochelid genera Nothrholaspis and Macrholaspis, the new species presents a unique combination of characters that argues against its inclusion in either genus, or in any other recognised macrochelid genus. A dichotomous key that distinguishes Allogynaspis from related macrocheline genera is included in the text.

On two new synonyms of the orb-weaving spider Orsinome vethi (Hasselt, 1882) (Araneae, Tetragnathidae).

The genus Orsinome was established by Thorell in 1890 with O. vethi (Hasselt, 1882) as the type species. It presently comprises 17 described species (World Spider Catalog 2018), of which two are known from India: O. armata Pocock, 1901 and O. listeri Gravely, 1921 (World Spider Catalog 2018). While studying spiders from the Indian Himalayas and north-East India, we examined the type specimens of Labulla nepula Tikader, 1970 and found it to be misidentified and placed erroneously in the family Linyphiidae Blackwall, 1859. Moreover, Orsinome listeri Gravely, 1921 described from the Eastern Himalayas was also found to be indistinguishable from O. vethi (Hasselt, 1882). In this paper, we provide detailed illustrations of the types of L. nepula Tikader and O. listeri Gravely and synonymize it with O. vethi (Hasselt, 1882) based on the cheliceral dentition and genital morphological characters.

Two new species of the genus Paramitraceras Pickard-Cambridge, 1905 (Opiliones: Laniatores: Stygnopsidae) from Chiapas, Mexico.

Parainitraceras pickardcanibridgei sp. nov. and Paramitraceras tzotzil sp. nov. from Chiapas, Mexico are described based on specimens previously determined as Paramitraceras granulatum Pickard-Cambridge, 1905 by Goodnight and Goodnight. The male genitalia of the new species and P. granulatum are illustrated with scanning electronic micrographs (SEMs) or drawings derived from them. The importance of the ocular tubercle, cheliceral dentition and sexual dimorphism, pedipalpal armature and male genitalia as taxonomic characters within the genus is discussed as well as differences and similarities between Paramitraceras Pickard-Cambridge, 1905 and its most similar genus, Sbordonia Šilhavý, 1977.

Neodrassex, a new genus of the Leptodrassex group (Araneae, Gnaphosidae) from South America

The new genus Neodrassex is proposed to include two new species of Gnaphosidae from Brazil. Neodrassex aureus sp. nov. is described from Amazonas, Paraná and Rio Grande do Sul states, and N. iguatemi sp. nov. is described from Paraná state. Neodrassex gen. nov. is characterized by small size, pale coloration, large anterior median eyes surrounded by black pigmentation, absence of a dorsal abdominal scutum in males and by the cheliceral dentition with 2-3 teeth on the promargin and 2-4 on the retromargin. The new genus is tentatively placed at the Leptodrassex group.

Computed tomography recovers data from historical amber: an example from huntsman spiders

Computed tomography (CT) methods were applied to a problematic fossil spider (Arachnida: Araneae) from the historical Berendt collection of Eocene (ca. 44-49 Ma) Baltic amber. The original specimens of Ocypete crassipes Koch and Berendt 1854 are in dark, oxidised amber and the published descriptions lack detail. Despite this, they were subsequently assigned to the living Pantropical genus Heteropoda Latreille, 1804 and are ostensibly the oldest records of huntsman spiders (Sparassidae) in general. Given their normally large size, and presumptive ability to free themselves more easily from resin, it would be surprising to find a sparassid in amber and traditional (optical) methods of study would likely have left O. crassipes as an equivocal record--probably a nomen dubium. However, phase contrast enhanced X-ray CT revealed exquisite morphological detail and thus 'saved' this historical name by revealing characters which confirm that it's a bona fide member both of Sparassidae and the subfamily Eusparassinae. We demonstrate here that CT studies facilitate taxonomic equivalence even between recent spiders and unpromising fossils described in older monographs. In our case, fine structural details such as eye arrangement, cheliceral dentition, and leg characters like a trilobate membrane, spination and claws, allow a precise referral of this fossil to an extant genus as Eusparassus crassipes (Koch and Berendt 1854) comb. nov.

First description of the female of Sarotesius melanognathus Pocock 1898 (Araneae: Sparassidae: Palystinae)

The female of Sarotesius melanognathus Pocock 1898 is described for the first time. According to characters of the copulatory organs of both male and female as well as to cheliceral dentition the monotypic genus is placed in the Palystinae Simon 1897.

Natural history of coastal Peruvian solifuges with a redescription of Chinchippus peruvianus and an additional new species (Arachnida, Solifugae, Ammotrechidae)

Two species of Chinchippus (Ammotrechidae) were studied in central Peru. Both species are endemic to the hyper-arid coastal desert and appear to derive most of their energy and nutrients from maritime prey, such as intertidal amphipods feeding on beach-cast algae or as arthropod scavengers feeding upon seabird and pinniped carcasses. Data on the spatial distribution of the two species were obtained from analyzing stomach contents of one common predator, the gecko Phyllodactylus angustidigitus, and suggest that both species are more abundant in insular than in mainland habitats. We redescribe Chinchippus peruvianus Chamberlin 1920, known only from a female specimen and describe the male for the first time while C. viejaensis is recognized as new. The new species is distinguished from C. peruvianus by its darker coloration, smaller size, and differences in cheliceral dentition. In the process of investigating the ecology of terrestrial organisms in the coastal desert and guano islands of central Peru, we have come across a series of Chinchippus peruvianus Chamberlin 1920 and a closely related species. These solifuges, along with other terrestrial predators, thrive in places that could be defined as a barren land of gravel, sand, and granitic outcrops - a moonscape where arachnids and lizards somehow manage to survive, reproduce, and colonize new habitats. The western coast of South America is among the driest places on Earth (Dietrich & Perron 2006), where arid conditions have persisted for the last 14 million years (Alpers & Brimhall 1988). Facing this hyper-arid ecosystem is one of the world's most productive marine ecosystems, the Peru-Chile cold current (Tarazona & Arntz 2001). The stark contrast in productivity promotes the exchange of energy and nutrients between these two adjacent ecosystems, and marine-derived resources subsidize terrestrial predators along the Peruvian coast (Catenazzi & Donnelly 2007a) and in other coastal deserts (Polis & Hurd 1996). In this study we describe the taxonomy and natural history of the two Chinchippus species and explore their distribution in relation to the availability of marine-derived resources. The genus Chinchippus was established by Chamberlin (1920) based on a single female from the Peruvian island of Chincha. He considered it to belong to the African family Daesiidae. Roewer (1934) included Chinchippus in the ammotrechid subfamily Saronominae based on the segmenta- tion of legs I, II, and IV and the palpal spination. Muma (1976) tentatively included it with the saronomines although its placement was still based on Chamberlin's sole female. Based on Chamberlin's single female, the genus Chinchippus can be recognized by: all the legs having a single tarsal segment, no claws on leg I, stridulating ridges on the mesal surface of the chelicera, lateral plates of the ''rostrum'' shorter than the median plates, and a recurved cephalothorax.

Description and ecology of a new species of sun spider (Arachnida: Solifugae) from the Brazilian Cerrado

A new species of solifuge from São Paulo State, south-eastern Brazil, is described, together with its phenology, habitat use, activity pattern and the effect of fire on the population. Mummucia coaraciandu n. sp. differs from other Mummuciidae in cheliceral dentition and pleurite coloration. Over a one-year period, 649 individuals of M. coaraciandu were captured in 72 pitfall traps distributed in three Cerrado physiognomies: borders of gallery forest (N=53), campo sujo (N=561) and campo cerrado (N=35). The species is diurnal and showed two peaks of surface activity during the year: the highest peak occurred in the cold–dry season (June to July) and the smaller peak in the middle of the warm–wet season (December to February). The number of individuals per trap was negatively correlated with the mean monthly temperature, but showed no correlation with the monthly precipitation. The sex ratio was male-biased (7:1) and the number of males trapped was positively correlated with the number of reproductive females. More individuals were trapped in burned areas when compared with unburned areas 1 month after the fire. This difference between the two areas was not observed 1 month before and 3–4 months after the passage of the fire (when the vegetation had recovered). Mummucia coaraciandu is the second solifuge described from the Brazilian Cerrado and its ecology is very similar to that of Mummucia mauryi from Caatinga vegetation.

SUB-FOSSIL SPIDERS FROM HOLOCENE PEAT CORES

An attempt was made to recover identifiable spider sub-fossils from peat cores taken from a post-glacial basin mire in Cheshire, north-west England. Although the features normally required to identify specimens to species level in taxonomic keys were rarely preserved, carapace morphology and cheliceral dentition allowed unequivocal identification to species level in many cases. Current lack of knowledge of the autecology of wetland spiders prevents any conclusion regarding the paleoecological conditions, but the technique could reveal insights into the post-glacial development of the spider faunal assemblage of mires.

Salticidae (Arachnida: Araneae) from the Oriental, Australian and Pacific regions, XV. New species of Astieae from Australia

Eight new species of Astieae spiders are described: Arasia mullion, Helpis abnormis, H. kenilworthi, H. risdonica, H. tasmanica, Sondra bickeli, S. brindlei and S. samambrayi. Arasia aurea (Koch) is transferred to the genus Sondra. Remarks on relationships of Astieae are provided and distributional maps of studied species are given. ZABKA, MAREK, 2002. Salticidae (Arachnida: Araneae) from the Oriental, Australian and Pacific regions, XV. New species of Astieae from Australia. Records of the Australian Museum 54(3): 257–268. Records of the Australian Museum (2002) Vol. 54: 257–268. ISSN 0067-1975 www.amonline.net.au/pdf/publications/1365_complete.pdf The group Astieae was proposed by Simon (1901) for nine Old and New World genera. The most comprehensive study of the group was provided by Wanless (1988). He described as new the genera Jacksonoides, Sondra and Tauala and excluded Charippus Thorell, Lagnus Koch, Aruana Strand, Agelista Simon, Anaurus Simon, Lapsias Koch and Titanattus Peckham & Peckham from Simon’s list. Wanless also suggested that Adoxotoma, described by Simon (1909) in Astieae, should be excluded. My studies indicate that the genus should be retained within the group (Żabka, 2001). More recently, two additional papers dealt with the Astieae (Żabka, 1995; Gardzinska, 1996), the former describing Megaloastia from Western Australia, and the latter dealing with new species of Arasia, Helpis and Tauala. Currently Astieae comprises the following genera: Astia, Arasia, Helpis, Adoxotoma, Jacksonoides, Megaloastia, Sondra and Tauala. The first three of which are found in Australia, on adjacent islands (Patoleta & Żabka, 1999), and in New Guinea; Helpis is found also in New Zealand (Żabka, in prep.). The other genera are recorded from Australia only. Whether the group, as it is now formed, is monophyletic or not is a matter for future study. At least Astia, Arasia, Helpis, Adoxotoma and Megaloastia seem closely related, sharing similar body form, cheliceral dentition and genitalic structure. Tauala and Sondra differ in cephalothorax proportions (EFL:CL, CL:CW) and carapace form (boxrather than pear-shaped) whereas Jacksonoides has some genitalic similarities to Aruana (see Wanless, 1988). Except for Adoxotoma, the cheliceral dentition is of the pluridentati pattern and is generally quite consistent within the Astieae. In Adoxotoma an intermediate pluri-fissidentati stage is present (Żabka, 2001). Material and methods The material is deposited in the Australian Museum, Sydney (AMS); specimens were collected during biological surveys conducted by the Museum. Specimens have been examined using methods described previosuly (Żabka, 1991a). Abbreviations used are: AEW, anterior eyes width; AL, abdomen length; AMS, Australian Museum, Sydney; BB, B. Baehr; CL, cephalothorax length; CW, cephalothorax width; EFL, eye field length; GC, G. Cassis; GM, G. Milledge; j, (or, when more than one, jj) unsexed juvenile specimens; MG, M. Gray; MŻ, M. Żabka; NSW, New South Wales; PEW, posterior eyes width. 258 Records of the Australian Museum (2002) Vol. 54 Genus Arasia Simon, 1901 Type species Astia mollicoma L. Koch, 1880, p. 1158. Arasia mullion n.sp.

The systematic position of the scorpion genusCharmus

Summary In 1917, Birula proposed a new classification of the order Scorpiones and included the genus Charmus under the family Vejovidae, creating a new subfamily Charminae to accommodate it. His argument for the reclassification is that the scorpions of this genus possess a pentagonal sternum. The form of the sternum is not the sole criterion for deciding whether a scorpion belongs to one family or another. Other characters, both morphological and anatomical, like the cheliceral dentition, trichobothrial distribution and the chitinous reinforcement of the lung lamellae indicate unmistakably its affinity to the family Buthidae.

Coexistence and Anatomical Similarity in Two Genera of Mites, Veigaia and Asca

Ecologic characteristics of species of two genera of soil mites, Veigaia and Asca, were investigated. Among ten species of Veigaia, all collected from deciduous forests in central Maryland, there were considerable differences in vertical distribution; some species were restricted to leaf litter, some occurred mainly down in the A, layer, and others were intermediate. There were also marked dissimilarities in overall size and in length and form of the chelicerae. These differences probably were related to differences in kinds of prey captured. Species of Asca were separated partly by habitat and partly by differences in cheliceral dentition. The relationship between anatomical similarity and frequency of coexistence was investigated. Moderately similar species were found together more often than markedly dissimilar forms. Very similar species were found together rarely or not at all.