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The Transition Radiation Detector (TRD) was designed and built to enhance the capabilities of the ALICE detector at the Large Hadron Collider (LHC). While aimed at providing electron identification and triggering, the TRD also contributes significantly to the track reconstruction and calibration in the central barrel of ALICE. In this paper the design, construction, operation, and performance of this detector are discussed. A pion rejection factor of up to 410 is achieved at a momentum of 1 GeV/c in p-Pb collisions and the resolution at high transverse momentum improves by about 40% when including the TRD information in track reconstruction. The triggering capability is demonstrated both for jet, light nuclei, and electron selection.
The Transition Radiation Detector (TRD) was designed and built to enhance the capabilities of the ALICE detector at the Large Hadron Collider (LHC). While aimed at providing electron identification and triggering, the TRD also contributes significantly to the track reconstruction and calibration in the central barrel of ALICE. In this paper the design, construction, operation, and performance of this detector are discussed. A pion rejection factor of up to 410 is achieved at a momentum of 1 GeV/c in p-Pb collisions and the resolution at high transverse momentum improves by about 40% when including the TRD information in track reconstruction. The triggering capability is demonstrated both for jet, light nuclei, and electron selection.
The Transition Radiation Detector (TRD) was designed and built to enhance the capabilities of the ALICE detector at the Large Hadron Collider (LHC). While aimed at providing electron identification and triggering, the TRD also contributes significantly to the track reconstruction and calibration in the central barrel of ALICE. In this paper the design, construction, operation, and performance of this detector are discussed. A pion rejection factor of up to 410 is achieved at a momentum of 1 GeV/c in p–Pb collisions and the resolution at high transverse momentum improves by about 40% when including the TRD information in track reconstruction. The triggering capability is demonstrated both for jet, light nuclei, and electron selection.
This paper summarizes current knowledge about Central African pholcids. Central Africa is here defined as the area between 10°N and 7°S and between 6°E and 18°E, including mainly the Lower Guinean subregion of the Guineo-Congolian center of endemism. This includes all of Gabon, Equatorial Guinea, São Tomé and Príncipe, most of Cameroon and Congo Republic, and parts of the neighboring countries. An annotated list of the 14 genera and 79 species recorded from this area is given, together with distribution maps and an identification key to genera. Seven species are newly described: Anansus kamwai sp. nov., Leptopholcus gabonicus sp. nov., Ninetis faro sp. nov., Pholcus punu sp. nov., P. rawiriae sp. nov., Spermophora abibae sp. nov., and S. awalai sp. nov. Additional new records are given for 16 previously described species, including 17 new country records. Distribution and diversity patterns are compared with data on West and East Africa. While West Africa contains a similar set of genera it is significantly less diverse than Central Africa. East Africa is taxonomically more distinct. It has similar levels of diversity as Central Africa, but appears to be less undersampled.
Daddy-long-leg giants: revision of the spider genus Artema Walckenaer, 1837 (Araneae, Pholcidae)
(2017)
This is the first revision of Artema Walckenaer, 1837, a genus consisting of large and phylogenetically interesting species. Even though Artema is not species-rich (now eight nominal species), it has suffered from poor descriptions and synonymies. Our main goal was to gather all available material and to clarify species limits. Four species are easily distinguished from other congeners: Artema atlanta Walckenaer, 1837, the type species; A. kochi Kulczyński, 1901 (revalidated); A. bunkpurugu Huber & Kwapong, 2013; and A. nephilit sp. nov. All other species are problematic for varying reasons: species limits are unclear between A. doriae Thorell, 1881 and A. transcaspica Spassky, 1934; A. magna Roewer, 1960 and A. ziaretana (Roewer, 1960) are problematic because they are based on female and juvenile types respectively and little new material is available. The material available to us suggests the existence of a few further species; however, they are not formally described, either because of small sample sizes (Artema sp. a and A. sp. b are represented by only one specimen each) or because of unclear species limits (between Artema sp. c, A. transcaspica and A. doriae).This study is the first serious step towards understanding the genus. Intensive collecting effort is needed in order to fully clarify species limits.
Künstlicher Traubenwicklerbefall : eine neue Möglichkeit zur Prüfung von Insektiziden im Weinbau
(2006)
Bei der Prüfung von Insektiziden gegen die Traubenwickler Lobesia botrana DEN. & SCHIFF. und Eupoecilia ambiguella HBN. (Lepidoptera: Tortricidae) im Freiland ist ein ausreichender Befall mit den Schadinsekten notwendig, um statistisch auswertbare Ergebnisse zu erzielen. Dem steht jedoch ein jährlich stark wechselnder Befallsdruck und ein oft stark geklusterter Befall, selbst innerhalb einer eng umgrenzten Rebanlage, entgegen. Hinzu kommen erhebliche Probleme mit dem richtigen Timing der Behandlung, bedingt durch eine sehr lange Flugzeit der Traubenwicklerarten, was häufig zu einer geringen Effizienz und schlechten Vergleichbarkeit der Mittel führt. Für die Entwicklung von Insektiziden bedingen diese Voraussetzungen eine große Anzahl von Versuchen, die mit hohen Kosten verbunden sind Abhilfe kann für viele Fragestellungen ein künstlich erzeugter Befall geben. Die Methode soll hier kurz vorgestellt und die Anwendung exemplarisch an Versuchen mit beiden Traubenwicklerarten dargestellt werden.
The North American-Caribbean genera Pholcophora Banks, 1896 and Tolteca Huber, 2000 are representatives of Ninetinae, a group of small, cryptic, and thus poorly known pholcid spiders. We present the first comprehensive revisions of the two genera, including extensive SEM data and descriptions of seven new species from Mexico (Pholcophora mazatlan Huber sp. nov., P. papanoa Huber sp. nov., P. tehuacan Huber sp. nov., Tolteca huahua Huber sp. nov., T. manzanillo Huber sp. nov., T. oaxaca Huber sp. nov., and T. sinnombre Huber sp. nov.). We add new CO1 sequences of nine species to previously published molecular data and use these for a preliminary analysis of relationships. We recover a North American-Caribbean clade including ‘true’ (mainland) Pholcophora, Tolteca (Mexico), and a Caribbean clade consisting of the genus Papiamenta Huber, 2000 (Curaçao) and Caribbean ‘Pholcophora’. First karyotype data for Tolteca (2n♂ = 13, X1X2Y and 15, X1X2Y, respectively) reveal a strong reduction of the number of chromosome pairs within the North American-Caribbean clade, and considerable karyotype differentiation among congeners. This agrees with considerable CO1 divergence among species of Tolteca but contrasts with very inconspicuous morphological divergence. Environmental niche analyses show that the widespread P. americana Banks, 1896 (western USA, SW Canada) occupies a very different niche than its Mexican congeners and other close relatives. Caribbean taxa also have a low niche overlap with ‘true’ Pholcophora and Tolteca, supporting the idea that Caribbean ‘Pholcophora’ are taxonomically misplaced.
The Andean genus Priscula Simon, 1893 includes the largest Neotropical pholcid spiders, but due to their mostly cryptic lifestyle they remain poorly collected and poorly studied. Many species available in collections remain undescribed and nothing has been published about the phylogeny and the biology of the genus. Here, we deal with a recent collection of Priscula spiders from Ecuador, the country of origin of the type species, P. gularis Simon, 1893. We describe eight new species, collected at 17 localities at altitudes from 640–3160 m, all based on males and females: P. azuay sp. nov., P. llaviucu sp. nov., P. espejoi sp. nov., P. esmeraldas sp. nov., P. chapintza sp. nov., P. pastaza sp. nov., P. bonita sp. nov., and P. lumbaqui sp. nov. We use a sample of approximately 26 species-level taxa, mostly from Ecuador and Venezuela, to propose a first hypothesis about relationships within the genus. Our data (mainly CO1) suggest the existence of five species groups, three of which are represented in Ecuador. The cave-dwelling P. pastaza sp. nov. is only slightly troglomorphic (paler than usual; anterior median eyes strongly reduced or lost) but differs dramatically from forest-dwelling congeners in its biology: it hangs fully exposed in its web during the day; it produces egg sacs with only 6–7 eggs (average in 15 other species: 42 eggs); and it produces the largest eggs relative to body size of all studied species.
We present a comprehensive revision of the pholcid spider collection of M.A. González-Sponga, who between 1998 and 2011 described 22 new genera and 51 new species of Pholcidae from Venezuela. In addition, we treat the pholcid material collected during three expeditions to Venezuela conducted between 2002 and 2020. Of González-Sponga’s pholcid taxa we recognize three genera and 24 species as valid. We describe 43 new species (all from males and females) in one new and 13 previously described genera; four genera are newly recorded for Venezuela. We describe the previously unknown females of 15 species, present new records for 46 previously described species, synonymize one genus and one species, and correct numerous minor errors in previous publications on Venezuelan pholcids. At the generic level, the Venezuelan pholcid fauna now appears fairly well known, but available data on distribution and endemism suggest that many species remain undiscovered and undescribed. Despite the obvious gaps, our data are congruent with previous studies on other taxa that have the highest levels of endemism in the Venezuelan Andes, the Coastal Ranges, and the Guyana Highlands. The Falcón Region in particular shows a complex mosaic of biogeographic relationships with other regions. We provide new biological data on numerous species. We document the first cases of evolutionary microhabitat shifts in the genera Mecolaesthus Simon, 1893 and Priscula Simon, 1893. We document several cases of close congeners sharing localities, usually in slightly to conspicuously different microhabitats, sometimes apparently in identical microhabitats. We document several cases of color polymorphism, mostly intersexual, in Metagonia conica (Simon, 1893) both intersexual and among males. We document further cases of two rare phenomena in Pholcidae: use of specific non-silken structures for retreats (in Pisaboa Huber, 2000) and egg parasitism (in Priscula).
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.
The first measurement of two-pion Bose–Einstein correlations in central Pb–Pb collisions at √sNN=2.76 TeV at the Large Hadron Collider is presented. We observe a growing trend with energy now not only for the longitudinal and the outward but also for the sideward pion source radius. The pion homogeneity volume and the decoupling time are significantly larger than those measured at RHIC.
Inclusive transverse momentum spectra of primary charged particles in Pb–Pb collisions at √sNN=2.76 TeV have been measured by the ALICE Collaboration at the LHC. The data are presented for central and peripheral collisions, corresponding to 0–5% and 70–80% of the hadronic Pb–Pb cross section. The measured charged particle spectra in |η|<0.8 and 0.3<pT<20 GeV/c are compared to the expectation in pp collisions at the same sNN, scaled by the number of underlying nucleon–nucleon collisions. The comparison is expressed in terms of the nuclear modification factor RAA. The result indicates only weak medium effects (RAA≈0.7) in peripheral collisions. In central collisions, RAA reaches a minimum of about 0.14 at pT=6–7 GeV/c and increases significantly at larger pT. The measured suppression of high-pT particles is stronger than that observed at lower collision energies, indicating that a very dense medium is formed in central Pb–Pb collisions at the LHC.
The inclusive charged particle transverse momentum distribution is measured in proton–proton collisions at s=900 GeV at the LHC using the ALICE detector. The measurement is performed in the central pseudorapidity region (|η|<0.8) over the transverse momentum range 0.15<pT<10 GeV/c. The correlation between transverse momentum and particle multiplicity is also studied. Results are presented for inelastic (INEL) and non-single-diffractive (NSD) events. The average transverse momentum for |η|<0.8 is 〈pT〉INEL=0.483±0.001 (stat.)±0.007 (syst.) GeV/c and 〈pT〉NSD=0.489±0.001 (stat.)±0.007 (syst.) GeV/c, respectively. The data exhibit a slightly larger 〈pT〉 than measurements in wider pseudorapidity intervals. The results are compared to simulations with the Monte Carlo event generators PYTHIA and PHOJET.
Rapidity and transverse momentum dependence of inclusive J/ψ production in pp collisions at √s=7 TeV
(2011)
The ALICE experiment at the LHC has studied inclusive J/ψ production at central and forward rapidities in pp collisions at √s=7 TeV. In this Letter, we report on the first results obtained detecting the J/ψ through the dilepton decay into e+e− and μ+μ− pairs in the rapidity ranges |y|<0.9 and 2.5<y<4, respectively, and with acceptance down to zero pT. In the dielectron channel the analysis was carried out on a data sample corresponding to an integrated luminosity Lint=5.6 nb−1 and the number of signal events is NJ/ψ=352±32(stat.)±28(syst.); the corresponding figures in the dimuon channel are Lint=15.6 nb−1 and NJ/ψ=1924±77(stat.)±144(syst.). The measured production cross sections are σJ/ψ(|y|<0.9)=10.7±1.0(stat.)±1.6(syst.)−2.3+1.6(syst.pol.)μb and σJ/ψ(2.5<y<4)=6.31±0.25(stat.)±0.76(syst.)−1.96+0.95(syst.pol.)μb. The differential cross sections, in transverse momentum and rapidity, of the J/ψ were also measured.
The previously poorly known Southeast Asian spider genus Aetana Huber, 2005 is revised. Fifteen species are newly described, and the first SEM data and a first phylogenetic analysis of the genus are presented. Four species groups are well supported, one restricted to Borneo, two restricted to the Philippines, and one ranging from the Philippines to Fiji. The cladistic analysis and field observations suggest that the ancestor of Aetana built its web close to the ground, in confined spaces among and under rocks and logs. In at least two cases, evolutionary shifts of microhabitat resulted in species being adapted to life in higher forest strata, with correlated morphological and behavioral changes (lighter coloration; longer abdomen; additional sheet in web or more strongly domed web). The following species are newly described: A. abadae Huber, sp. nov., A. baganihan Huber, sp. nov., A. banahaw Huber, sp. nov., A. kiukoki Huber, sp. nov., A. libjo Huber, sp. nov., A. loboc Huber, sp. nov., A. lozadae Huber, sp. nov., A. manansalai Huber, sp. nov., A. ocampoi Huber, sp. nov., A. paragua Huber, sp. nov. and A. pasambai Huber, sp. nov. from the Philippines; A. gaya Huber, sp. nov., A. indah Huber, sp. nov., A. lambir Huber, sp. nov. and A. poring Huber, sp. nov. from northern Borneo. The female of A. kinabalu Huber, 2005 is newly described. A potential case of female genital dimorphism is documented in A. ocampoi Huber, sp. nov.
We describe several new species of the previously monotypic Panjange lanthana species group from the Philippines and document their extraordinary morphology. Some species show strong male genital asymmetry, a phenomenon that seems to be exceedingly rare in spiders. Males of most species have eye stalks, and in two species these eye stalks are among the longest ever recorded in spiders. Some species show a tendency for male genital (pedipalp) elongation, and one species has the longest and thinnest palps ever recorded in Pholcidae. A cladistic analysis is performed including all described and several undescribed species of Panjange (except for one “problem species”), supporting the lanthana group and its close relationship with members of the possibly paraphyletic cavicola group. The following eight new species are described: Panjange malagos Huber sp. nov.; Pa. casaroro Huber sp. nov.; Pa. camiguin Huber sp. nov.; Pa. hamiguitan Huber sp. nov.; Pa. isarog Huber sp. nov.; Pa. dinagat Huber sp. nov.; Pa. marilog Huber sp. nov.; Pa. bukidnon Huber sp. nov.
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.
We revise the Panjange nigrifrons group in Borneo and document an unexpected diversity in western Sarawak forests. Five species occur within 80 km from Kuching, each species being known from its type locality only. Further species occur east until Niah, but the genus seems to be absent from Sabah. We contrast this with another pholcid genus (Aetana Huber, 2005), which is diverse in Sabah and westward until Niah, but does not seem to occur in central and western Sarawak. Five species are newly described: Panjange kapit Huber, sp. nov., Panjange kubah Huber, sp. nov., Panjange niah Huber, sp. nov., Panjange pueh Huber, sp. nov., Panjange seowi Huber, sp. nov.; Panjange tahai (Huber, 2011) comb. nov. is transferred from Pholcus.
Two small, ground and litter-dwelling pholcid species from northern Borneo are described as representatives of a new genus, Hantu gen. nov.: H. kapit gen. et sp. nov. and H. niah gen. et sp. nov. Previous cladistic analyses suggested a closer relationship with the genera Savarna Huber, 2005 and Khorata Huber, 2005 (mainland Southeast Asia) than with the geographically closer genus Aetana Huber, 2005 (Borneo and Philippines to Fiji). Since the two species do not share any of the synapomorphies of Khorata and Savarna while having several synapomorphies on their own (ventral apophysis on male palpal coxa; male palpal trochanter apophysis with small teeth or scales; spines on male femora 1; high density of vertical hairs on male femora; presence of scape on epigynum), they are here proposed as representing a new genus.
The Southeast Asian Pholcus halabala species group is revised and re-delimited, based mainly on field observations (life color pattern, web design, position of egg-sac when carried by female, microhabitat) and ultrastructure (silk spigots, modifications of male cheliceral apophyses). The core group includes six leafdwelling species that have distinctive color patterns in life specimens (black and white or yellowish abdominal marks, dark pattern on posterior half of carapace) and build round to oval silk platforms on the undersides of leaves. Seven further species are tentatively assigned to the group pending further study. Several species originally assigned to the Pholcus halabala group are transferred to three newly proposed species groups, the Ph. krabi, Ph. buatong, and Ph. andulau groups. Nine species are newly described, four in the Ph. halabala group (Ph. khaolek Huber, sp. nov.; Ph. kuhapimuk Huber, sp. nov.; Ph. lintang Huber, sp. nov.; Ph. ubin Huber, sp. nov.); three in the Ph. krabi group (Ph. kipungit Huber, sp. nov.; Ph. krabi Huber, sp. nov.; Ph. narathiwat Huber, sp. nov.); one in the Ph. buatong group (Ph. buatong Huber, sp. nov.); and one in the Ph. andulau group (Ph. lambir Huber, sp. nov.). The females of Ph. satun Huber, 2011 and Ph. schwendingeri Huber, 2011 (both members of the buatong group) are newly described.