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A survey on sensory organs of both sexes of the harvestman Dicranopalpus ramosus classifies structure and frequency of campaniform sensilla, falciform setae, sensilla basiconica, slit sensilla, solenidia, spines, sensilla chaetica, trichomes (simple hairs) and plumose setae. Sensilla are equally distributed on the pedipalp tarsi of both males and females, but females show higher counts of campaniform and falciform setae than males. Females furthermore have about 1000 glandular plumose setae on each pedipalp, that at the same positions in males are replaced by sensilla chaetica. The walking legs of both sexes show a similar distribution of sensory organs, with females showing more sensilla basiconica at the legs I and II and more solenidia on the first pair of legs. Males have a large number of bipterate setae (about 2200 per specimen) at the metatarsi and tarsi of the third and fourth pair of legs. In females these are replaced by simple hairs. Although females show a similar (or slightly higher) number of leg sensilla than males, their density is higher due to their shorter legs. In both sexes the second pair of legs has the largest number of falciform setae, sensilla basiconica, chaetica and solenidia, followed by the legs I, III and IV. The first pair of legs has the highest density of falciform setae, sensilla basiconica and solenidia, followed by the legs II, III and IV. The genital operculum, sternites and tergites show a multitude of slit sensilla. The slit sensilla of the genital operculum and sternites are associated with insertion plaques of muscles operating the penis/ovipositor and regulating opisthosomal volume and hemolymph-pressure.
Adesmus martinsi (Coleoptera, Cerambycidae, Lamiinae, Hemilophini), a new species from Bolivia, is described, illustrated, and included in a previous key. The new species displays gender dimorphism in the pubescent pattern and in anatomical structure. Thus, Adesmus becomes the second genus recorded in the Hemilophini to have visual chromatic dimorphism.
The genus Spaeleoleptes was proposed by H. Soares in 1966 to accommodate the first Brazilian troglobitic species of harvestmen, Spaeleoleptes spaeleus H. Soares, 1966. In this work, we redescribe this species, including digital images of the type material and drawings of the male genitalia. Since its description, Spaeleoleptes has remained monotypic, and after 56 years, herein is described the second species of the genus, the troglobitic Spaeleoleptes gimli sp. nov. Both species share sexually dimorphic legs I and II with modified regions and swelling on the tibiae and patellae I and II; a penis with robust conductors covering all or part of the capsula interna and a capsula interna with two lateral projections. They are clearly separated by the shape of the modified region of the tibia; by the presence of an apical projection on the apical lamina of the pars distalis in S. spaeleus; and the lateral projections of the capsula interna, which is flattened in S. gimli. Spaeleoleptes gimli greatly increases the distributional range of the genus, as it is now recorded from caves located in two Brazilian phytophysiognomies from the Cerrado of Minas Gerais to the Caatinga of Bahia.
Two species new to science Willowsia sikkimensis sp. nov. and W. arunachalensis sp. nov., and one new record of the genus Willowsia Shoebotham, 1917 are described and illustrated here. The new species are mainly distinguished from the others on the basis of pigment pattern, scale type and chaetotaxy. The species were collected from the states of Arunachal Pradesh and Sikkim (India). Willowsia shiae Pan, Zhang & Chen, 2006 is recorded for the first time from India (Arunachal Pradesh) and redescribed with detailed chaetotaxic nomenclature. A key to the Indian species of Willowsia and a comparison table of related species are also provided.
We revise the Southeast Asian Pholcus bicornutus group in which males are characterized by a unique pair of horns on their ocular area, each of which carries at its tip a brush of hairs. In two species, the two hair brushes are ‘glued’ or ‘waxed’ together by an unidentified substance into a very consistently curved and pointed single median tip. In the other five species known, the hairs are unglued. We present a first revision of ocular modifications in Pholcidae and identify twenty supposedly independent origins. Most cases are in Pholcinae, and all but one case are limited to the male, suggesting sexual selection as the main driving force in the evolution of ocular modifications in Pholcidae. Previously, the Pholcus bicornutus group consisted of four species limited to the Philippines. We describe four new species, including three species from the Philippines (P. olangapo Huber, sp. nov.; P. kawit Huber, sp. nov.; P. baguio Huber, sp. nov.) and the first representative from outside the Philippines (P. mulu Huber, sp. nov. from Sarawak, NE Borneo) and provide new records and SEM data for three previously described species.
The southern South American genus Guaranita includes tiny spiders (body length ~1 mm) that lead reclusive lives under ground-objects and run rapidly when disturbed. As a result, they have been poorly collected and studied. Here we report on a recent collection of Guaranita spiders from Argentina, describing one new species (G. auadae Huber sp. nov.) and the previously unknown female of G. dobby Torres et al., 2016. In addition, we provide CO1 barcodes for all (now five) known species, first SEM data, and first chromosome data for the genus. The diploid number of Guaranita goloboffi Huber, 2000 (2n♂ = 11) is among the lowest in araneomorph spiders with monocentric chromosome structure.
Revisions of Holocnemus and Crossopriza: the spotted-leg clade of Smeringopinae (Araneae, Pholcidae)
(2022)
The genera Holocnemus Simon, 1873 and Crossopriza Simon, 1893 are revised. Together with Stygopholcus Kratochvíl, 1932 (revised recently) and the newly described genus Maghreba gen. nov., they constitute the spotted-leg clade within the northern clade of Smeringopinae. Males and females in this group are characterized by dark marks on the leg femora and tibiae. The native area of the spotted-leg clade ranges from northern Africa and the Mediterranean to Central Asia and NW India. A morphological cladistic analysis suggests that Holocnemus is paraphyletic while Crossopriza is monophyletic, but morphology seems only partly adequate to resolve phylogenetic relationships convincingly. The genus Holocnemus includes four species, all of which are redescribed: H. pluchei (Scopoli, 1763); H. reini (C. Koch, 1873) comb. nov. (transferred from Pholcus); H. caudatus (Dufour, 1820); and H. hispanicus Wiehle, 1933. The genus Maghreba gen. nov. includes eight species from NW Africa: M. aurouxi (Barrientos, 2019) gen. et comb. nov. (transferred from Holocnemus; redescribed, female newly described) and seven newly described species. The genus Crossopriza includes six previously described species (of which five are redescribed), and 18 newly described species. The Madagascan C. nigrescens Millot, 1946 is synonymized with C. lyoni (Blackwall, 1867). All new species are described on the basis of both sexes.
A new species of leaf insect, Phyllium (Phyllium) letiranti Cumming and Teemsma, new species (Phasmida: Phylliidae), is described from a series of males, females, and eggs from Peleng Island, Indonesia. This new species is the first record of the family Phylliidae on the island and is here differentiated from congeners. Keys to males, females, and eggs of the Phyllium species of Sulawesi and Peleng islands are included within.
The Oriental genus of Eurybrachidae (Hemiptera, Fulgoromorpha) Purusha Distant, 1906 is reviewed and a key to the genera of Eurybrachini is given. Two new species, P. bellissima sp. nov. and P. vietnamica sp. nov. are described from Myanmar and North Vietnam, respectively. Purusha rubromaculata Distant, 1906 is proposed as a junior synonym of P. reversa (Hope, 1843). All species are illustrated, including all type specimens and the male genitalia for the first time. Distribution maps, identification key to species and biological data are provided. The sexual dimorphism in the genus is discussed. Five species are currently placed in Purusha.
In this second part of the study, using a ‘clean’ dataset without very low precision landmarks and outliers, I describe how to compare mandibular size and shape using Procrustes methods in adult North American marmots. After demonstrating that sex differences are negligible, females and males are pooled together with specimens of unknown sex and species are compared using a battery of tests, that estimate both statistical significance and effect size. The importance of allometric variation and its potential effect on shape differences is also explored. Finally, to provide potential clues on founder effects, I compare the magnitude of variance in mandibular size and shape between the Vancouver Island marmot (VAN) and the hoary marmot, its sister species on the mainland. In almost all main analyses, I explore the sensitivity of results to heterogeneous sample size and small samples using subsamples and randomized selection experiments. For both size and shape, I find a degree of overlap among species variation but, with very few exceptions, mean interspecific differences are well supported in all analyses. Shape, in particular, is an accurate predictor of taxonomic affiliation. Allometry in adults, however, explains a modest amount of within-species shape change. Yet, there is a degree of divergence in allometric trajectories that seems consistent with subgeneric separation. VAN is the most distinctive species for mandibular shape and mandibular morphology suggests a long history of reduced variation in this insular population. Geometric morphometrics (GMM) is a powerful tool to aid taxonomic research. Regardless of the effectiveness of this family of methods and the apparent robustness of results obtained with GMM, however, large samples and careful measurements remain essential for accuracy. Even with excellent data, morphometrics is important, but its findings must be corroborated with an integrative approach that combines multiple lines of evidence to taxonomic assessment. The analytical protocol I suggest is described in detail, with a summary checklist, in the Appendix, not to miss important steps. All the analyses can be replicated using the entire dataset, which is freely available online. Beginners may follow all the steps, whereas more experienced researchers can focus on one specific aspect and read only the relevant chapter. There are limitations, but the protocol is flexible and easy to improve or implement using a programming language such as R.