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Femtosecond time division interferometry technique for measuring the tensor component of c(3)
No full textRineloricaria quilombola Chamon & Fichberg 2022, new species
No full textRineloricaria quilombola, new species (Figure 1, Table 1) Holotype. MZUSP 126901, 116.3 mm SL, Palmas, Taquaruçu, ribeirão Taquaruçuzinho na ponte para o povoado de Taquaruçu Grande, rio Tocantins drainage, -10.31555, -48.21638 16 April 2018, C. Chamon, J. Silva, I. Fichberg and E. Oliveira. Paratypes. All from Tocantins River basin. UNT 942, 3, 87.7 – 132.6 mm SL, córrego Imbé, Fazenda Traçadal, Paranã, -12.48333 -48.21666, 21 Mar 1999, Marques, E. et al. UNT 943, 3, 71.1 – 134.3 mm SL, córrego Cipó, Fazenda Traçadal, Paranã, -12.72805, -48.22944, 26 Jan 1999, Marques, E. et al. UNT 1094, 8, 54.3 –92.0 mm SL, ribeirão Manduca, Porto Nacional, -10.79416, -48.36666, 3 Oct 2001, Marques, E. et al. UNT 1713, 3, 44.0–110.3 mm SL, same locality as UNT 943, 4 Aug 2004, Marques, E. et al. UNT 1723, 6, 48.4 –75.0 mm SL, same locality and collect data of UNT 1713. UNT 15542, 2, 49.4 –114.0 mm SL, same locality of the holotype, 26 Jun 2016, Chamon, C., Oliveira, E., Silva, J. and Bezerra, C. UNT 15711, 6, 73.3 –97.0 mm SL, same locality as holotype, 18 Nov 2016, Chamon, C., Oliveira, E., Pereira, T., Silva, J. and Bezerra, C. UNT 15794, 2, 45.6 –50.0 mm SL, ribeirão Taquaruçu Grande, na chácara Irecê, Taquaruçu, Palmas, -10.31555, -48.21638, 15 Dec 2016, E. Oliveira and J. Silva. UNT 19246, 1, 61.2 mm SL, collected with the holotype. UNT 19262, 3, 59.6 – 111.5 mm SL, same locality of the holotype, 26 Apr 2016, Chamon, C., Oliveira, E. and Silva, J. UNT (uncatalogued), 4, 50.1–62.3 mm SL, ribeirão São João, Porto Nacional, -10.73660, -48.29243, 23 May 2022, Pelicice, F. Rocha, T., Fontoura, F., Parente, A.L. and Chamon, C. Non-types. UNT 945, 1, 98.6 mm SL, same locality of UNT 942, 26 Sep 2001, Marques, E. et al. UNT 956, 1, 107.6 mm SL, same locality as UNT 942, 25 Aug 1998, Marques, E. et al. UNT 1029, 20, 53.9 – 89.4 mm SL, córrego Taboca, Paranã, -12.5927778000, -48.1036111000, 7 Aug 2000, Marques, E. et al. UNT 1038, 1, 72.9 mm SL, same locality as UNT 945, 3 Oct 2001, Marques, E. et al. UNT 7190, same locality as UNT 942, 15 Aug 2005, Marques, E. et al. UNT 7911, 10, 40.0–77.6 mm SL, same locality of UNT 943, 24 Aug 2007, Marques, E. et al. Diagnosis. Rineloricaria quilombola is diagnosed among its congeners by a greater number of premaxillary teeth (up to 15 vs. up to 10 in all congeners, except R. aequalicuspis and R. castroi with 15; R. osvaldoi with 13 and R. uracantha with 12); and dentary teeth (up to 15 vs. up to 10 in all congeners, except R. aequalicuspis with 20, R. osvaldoi with 13; R. castroi and R. uracantha with 12). From R. aequalicuspis, it can be differentiated by having teeth with a principal inner cusp and an accessory smaller one (vs. teeth with inner and outer cusps of approximately the same size). From R. castroi, it is distinguished by color pattern without dark stripes on the pectoral, pelvic and anal fins (vs. pectoral, pelvic and anal fins with conspicuous dark stripes). From R. hasemani it is distinguished, by having the edge of snout straight in lateral view, absence of filaments on lower lip and by color pattern lacking a dark stripe on dorsal fin (vs. edge of snout upturned in lateral view, absence of filaments on lower lip and dark stripe on dorsal fin present). From R. lanceolata, by a wider body at cleithral width 16.5–20.1% of SL (vs. 13.8–16% of SL); presence of five lateral plates series in longitudinal rows below dorsal fin (vs. four lateral plates series); base of pectoral and pelvic-fins completely ochre or light brown without a hyaline area (vs. base of pectoral and pelvicfins with a hyaline circular area); and by the absence of a dark stripe in all fins, running parallel to the first rays (vs. dark stripe present). From R. osvaldoi, the new species is further diagnosed by a lower head depth (30.8–40.5 % vs. 42.2–61.3 % of HL), by having shorter snout length (45.5–51.4 vs. 50.3–68.8% of HL); triangular head in dorsal view (vs. rounded head in dorsal view); lower lip with elongated and organised rounded-shape fringes (vs. lower lip with short and unorganised triangular fringes); lower lip short not covering the gular area (vs. lower lip elongated, covering about 50% of the gular area); upper lip margin with long, rugged and regular papillae (vs. upper lip margin with short and inconspicuous papillae) (Fig. 2); head with regular rows of odontodes (vs. odontodes not forming regular rows); dimorphic male lateral head with short and spaced apart odontodes (vs large and very close hypertrophied odontodes). Description. Morphometric data in Table 1. Head and body strongly depressed. Dorsal profile of head triangular with tip of snout and distal margin of opercle rounded. Snout tip straight, not raised in lateral view. Snout with very small and elliptical naked area short and not reaching the first pore of infraorbital ramus of sensorial canal. Dorsal profile concave from tip of snout to dorsal-fin origin, and straight from this point to caudal-fin origin. Ventral profile straight from tip of snout tip to caudal-fin origin. Greatest body depth at the posterior border of supraocciptal; lowest body depth at caudal peduncle. Head short and very depressed. Odontodes of head small to moderate size, forming conspicuous ridges between nostrils on posterior nasal plates to posterior margin of parieto-supraoccipital and compound pterotic.Six infraorbital, infraorbital 1 with sensorial pore exposed ventrally, infraorbitals 2, 3 and 4 raised convexly from anterior region of snout to eye. Predorsal plates and first three lateral plates of dorsal series slightly keeled, covered with small odontodes. Eyes elliptical with a large and deep postorbital notch, slightly larger than half of the horizontal diameter of the orbit. Mouth opening large. Upper lip short and separated from the naked area of snout by an extremely thin row of plates covered by tiny odontodes; margin of upper lip adorned with long, rugged and regular papillae. Two rows of papillae between anteroventral border of upper lips and anterior border of premaxillary-ramus; lower lips covered by irregular sized papillae unorganised and regularly distributed around oral cavity; edge of lower lips with elongated and organised triangle-shape fringes. Maxillary barbel moderate in size, reaching the lower lip distal margin. Barbel adorned with very small papillae. Teeth acute and strongly bicuspidate; dentary teeth slightly larger than premaxillary; premaxilla with 8(8), 9(5), 10(3), 11(4)*, 12(1), 13(3) or 15(1) teeth and dentary with 8(6), 9(1), 10*(4), 11(7), 12(4), 13(1), 14(1) or 15(1) teeth; cuspids orange coloured, accessory cuspid almost the same size of principal one. Body covered by 27(7) or 28*(18) plates on median series, coalescence on 15(6), 16(9)* or 17 (10) and, 8(9), 9(9)* or 10(7) lateral abdominal plates. Mid-dorsal series with 2(15)*, 3(5) or 4(5) plates. Lateral line complete. Five longitudinal rows of plates at dorsal-fin origin. Lateral plates weakly keeled with odontodes along the lateral line pores slightly more developed than those at the rest of the body. Ventral region totally covered by plates from cleithrum to caudal peduncle. Ventral plates well organised in three sections. Anterior section with small, quadrangular plates on the pectoral girdle area. Second section includes large and trapezoidal plates between pectoral and pelvic girdles. Third section represented by the preanal shield formed by three large plates surrounding polygonal preanal plate. Dorsal fin (ii,7), dorsal-fin spinelet present, locking mechanism not functional. Dorsal-fin base with four to five plates. Pectoral fin (i,6), adpressed unbranched ray slightly surpassing pelvic-fin origin. Pelvic fin (i,5), depressed unbranched ray reaching anal-fin origin. Anal fin (i,5), with two plates on base. Caudal fin (i,10,i) emarginated, with short and thin filament on the upper caudal-fin ray. Lower caudal-fin ray filament absent. Coloration in alcohol (Fig. 3). Body background with light brown to beige coloration. Dorsal surface with five to six transverse dark brown bands: first one located at second or third dorsal-fin ray, extending toward pectoral-fin origin; second one at the distal edge of dorsal fin when adducted, extending toward to pelvic-fin origin; third one located at the distal edge of the pelvic fin when adducted; fourth, fifth and sixth ones located at caudal peduncle. First and second longitudinal bands occasionally faint, posterior ones darker and more conspicuous (Figs. 1 and 3). Second band occasionally wider in some specimens (Fig. 3A). Presence of sixth band on the caudal peduncle observed only in few specimens under 63 mm of SL (Fig. 3C). Dorsal surface of snout and head covered with irregular dark brown dots; more concentrated at nasal, frontal and posterior margin of the parieto-supraoccipital and compound pterotic. Posterior margin of compound pterotic with dark-brown to black tiny spots around the first pores of lateral-line canal. Specimens with less than 70 mm of SL present conspicuous dark brown lines between nostrils (along the nasal bones) and dark brown lines behind the postorbital notch and extending to supraoccipital (Fig. 3C). Lines less conspicuous or completely absent in larger specimens. Pores of sensorial canal of head and lateral line highlighted by dark brown or black chromatophores. Ventral surface background with beige coloration without dots, spots or bands (Fig. 1C). Dorsal surface of upper lip with two longitudinal light brown stripes, lower lip beige without dots or blotches. All fins with light brown or beige coloration covered with dark brown dots that usually run in parallel to fin-rays, dark spots could be faint on pelvic and anal fins; caudal fin with a conspicuous dark brown blotch on base and faint darker band on distal edge (Figs. 1 and 3). Coloration in life. Live coloration is very similar to color in alcohol, with a dorsal background ranging from ochre to grey and faint dorsal dark brown transversal bands. Dots and lines on snout and head are more conspicuous, as well as the dark brown dots on fins surface (Fig. 4). Sexual dimorphism. Head margin of mature males triangular, with short and spaced apart hypertrophied odontodes extending from postrostral plates to opercle, along margin of head; unbranched pectoral-fin ray and first four branched rays weakly covered dorsally by well-developed odontodes (Fig. 5). Distribution. The new species is known from upper and middle stretches of Tocantins River basin, in the municipalities of São Salvador, Paranã, Palmas (at Taquaruçu district) and Porto Nacional, Tocantins State, Brazil (Fig. 6). Ecological and conservation notes. Specimens from Taquaruçu were collected in streams (Taquaruçuzinho and Taquaruçu Grande, middle Tocantins River) with moderate to strong currents with clear water and background with rocks, stones, gravel and sand (Fig. 7A). Although the Palmas region is an area of influence of the Lajeado reservoir, at Taquaruçu district, the area is relatively preserved since it is sheltered within the environment protected area (APA) of Serra do Lajeado. Thus, these streams have preserved riparian forest in most of their courses. Still, there is concern due to water withdrawal of the headwaters for agricultural irrigation and recreation activities. Other localities where the species is distributed, include Cipó, Taboca and Imbé streams, that are located at the influence area of São Salvador and Peixe Angical reservoirs (upper Tocantins River), near the confluence of Paranã and Tocantins rivers; and Manduca and São João streams (Fig. 7B), located upstream Lajeado reservoir, at Porto Nacional municipality. Most of nearby areas of these streams were strongly altered by the implementation of reservoirs (e.g. São Salvador, Peixe Angical and Lajeado), and agricultural expansion. Even so, the streams are preserved with moderate riparian forest on its courses According to GeoCAT analysis, the new species Extent of Occurrence (EOO) is 4,822 km 2 and Area of Occupancy (AOO) is 28.000 km 2, based solely on these criteria, IUCN criteria suggest that the species is Endangered (EN). However, there was no capture effort since 2007, in addition, other biological aspects of the new species, such as population size and generational time are not known. Thus, we suggest that Rineloricaria quilombola should be categorised as deficient data (DD) according to the International Union for Conservation of Nature categories and criteria (IUCN, 2021). Etymology. The specific epithet (a noun in apposition) is in honour of all the remaining Quilombola population of the state of Tocantins, which hosts more than 40 communities called Quilombos. Quilombos were specifically communities created by fugitive enslaved African-Brazilian people in Brazil. These places became centers of resistance for enslaved people and their descendents. These communities are legally protected by the Brazilian government yet they are under constant threat related to the expansion of agribusiness and land speculation. Part of the distribution area of the new species is inserted or close to some of these communities.Published as part of Chamon, Carine C. & Fichberg, Ilana, 2022, Rineloricaria quilombola: a new species of whiptail catfish (Siluriformes, Loricariidae, Loricariinae) from upper and middle Tocantins River basin, Brazil, pp. 58-70 in Zootaxa 5194 (1) on pages 59-66, DOI: 10.11646/zootaxa.5194.1.3, http://zenodo.org/record/714189
Measurement of the ratio of prompt χ c to J / ψ production in pp collisions at √s = 7 TeV
Full text linkThe prompt production of charmonium χ c and J / ψ states is studied in proton-proton collisions at a centre-of-mass energy of √s = 7 TeV at the Large Hadron Collider. The χ c and J / ψ mesons are identified through their decays χ c → J / ψ γ and J / ψ → μ + μ - using 36 pb - 1 of data collected by the LHCb detector in 2010. The ratio of the prompt production cross-sections for χ c and J / ψ, σ (χ c → J / ψ γ) / σ (J / ψ), is determined as a function of the J / ψ transverse momentum in the range 2 < p T J / ψ < 15 GeV / c. The results are in excellent agreement with next-to-leading order non-relativistic expectations and show a significant discrepancy compared with the colour singlet model prediction at leading order, especially in the low p T J / ψ region
Pseudacanthicus pitanga Chamon, 2015, sp. nov.
No full textPseudacanthicus pitanga sp. nov. (Figs. 1–2; Tab. 1) Holotype. MZUSP 34296, 220.7 mm SL, Serra dos Carajás, bedrock at rio Itacaiunas, Serra dos Carajás, Pará, Brazil, 05032'00"W 0552'00"S, Nov 1983, M. Goulding. Paratypes. Brazil. Pará State. INPA 4502, 1, 164.1 mm SL, rio Tocantins, Tucuruí, 345 ' 39.16 "S, 4939 ' 50.85 "W, 0 1 May 1986, F. Martinho. INPA 4558, 4, 91.4–147.5, rio Tocantins, downstream to Tucuruí Dam, 346 ' 2.84 "S, 4939 ' 36.68 "W, 0 9 Oct 1984, G. M. dos Santos. INPA 4559, 1, 148.1 mm SL, poço do Paulo, rio Tocantins, Tucurui, 345 ' 31.63 "S, 4939 ' 50.75 "W, 26 Jul 1980, Equipe Ictiologia INPA (Lucia Rapp Py Daniel et al). INPA 6308, 1, 94.1 mm SL, Tucurui, downstream to Tucuruí Dam, 345 ' 58.19 "S, 4939 ' 43.57 "W. INPA 6311, 7, 30.2–230.3 mm SL, rio Tocantins, 345 ' 59.43 "S, 4939 ' 40.41 "W. INPA 6348, 1, 270.0 mm SL, rio Tocantins, Jatobal, 428 ' 26.61 "S, 4927 ' 18.23 "W, 0 5 Jul 1982, M. Jegu. INPA 6349, 1, 252.0 mm SL, Igarapé Jatobal, Tucuruí, 31 Oct 1980, Equipe Ictiologia INPA. INPA 6350, 1, 300.0 mm SL, rio Tocantins, Breu Branco, 44 ' 4.52 "S, 4938 ' 12.87 "W, 31 Oct 1980, Equipe Ictiologia INPA. INPA 10919, 1, 210.4 mm SL, rio Tocantins, downstream to Tucuruí Dam, 0345' 58 ”S, 04940' 21 ”W, 0 1 Nov 1980, Equipe Ictiologia INPA. MZUSP 24135, 1, 110.7 mm SL, rio Tocantins, lagoon in front of Jatobal, Jatobal, 04939'00"W 0434'00"S, 16 Sep 1970, Expediçao; à Permanente a Amazônia (Heraldo A. Britski et al.). MZUSP 34295, 6, 170.3 – 256.9 mm SL, 1 esq., 236,3 mm SL, rio Itacaiunas, Caldeirão, 05032'00"W 0552'00"S, 0 4 May 1983, M. Goulding. MZUSP 115275, 1, 181.1 mm SL, collected with the holotype. Tocantins State. UNT 857, 1, 170.1 mm SL, rio Tocantins, Brejinho de Nazaré, 115 ' 24 "W 4834 ' 19 "S, 17 Nov 1997, Equipe Neamb (Anderson B. Soares et al). UNT 960, 1, 200.7 mm SL, rio Tocantins, Brejinho de Nazaré, 115 ' 24 "W 4834 ' 19 "S, 18 Set 2003, Equipe Neamb. UNT 967, 1, 87.3 mm SL, rio Tocantins, Fazenda Traçadal, Paranã, 1228 '099"W 4814 ' 47 "S, 27 Jul 1999, Equipe Neamb. UNT 8505, 1, 259.0 mm SL, rio Tocantins, near the confluence with rio Santo Antônio, Peixe, 1131 ' 17 "W 4837 ' 59 "S, 17 Oct 2001, Equipe Neamb. UNT 9061, 1, 224.2 mm SL, rio Maranhão at the place of UEH São Salvador, São Salvador, 1248 ' 55 "W 4814 ' 45 "S, 18 Jun 2006, A. Santana. UNT 1109, 1, 146.8 mm SL, rio Sono, Pedro Afonso, 859 ' 54 "W 4814 ' 17 "S, 10 Ago 2001, Equipe Neamb. UNT 10297, 1, 228.5 mm SL, rio Tocantins, border of Miracema and Tocantínia, 942 ' 59 "W 4821 ' 39 "S, May 2009, Equipe CMT Ambiental. Non-type material. Brazil, Pará state, rio Tocantins. ZMA 119.395, 3, 88.5–89.2 mm SL, Tucuruí, about 2 km below dam, 346 ' 29.47 "S 4939 ' 9.64 "W, 9 Oct 1984, G. Mendes dos Santos. ZMA 119.829, 1, 82.8 mm SL, Cametá, 0214'S, 04930'W, Jul 1985, A. Werner. No data. AMNH 97659, 1, 82.8 mm SL. Diagnosis. Pseudacanthicus pitanga, sp. nov., is distinguished from its congeners (except P. leopardus) by its color pattern with intense orange to red fins (vs. dark background color with white spots in P. serratus and P. fordii or gray background color with black blotches in P. histrix and P. s pi n os u s). It can be distinguished from P. leopardus by the presence of dark blotches anostomosing to form continuous zigzag bands alongside longitudinal keels; absence of blotches on ventral surface of body; faint blotches on head and all fins with orange to red color on unbranched ray and sometimes on subsequent branched rays (dark blotches conspicuous, never anostomosed; large dark blotches on ventral surface; conspicuous dark blotches on head; and red color restricted to dorsal and caudalfin rays). Pseudacanthicus pitanga can be further diagnosed from congeners by the following combination of osteological characters: contact of sphenotic with sixth infraorbital absent (Fig. 3; vs. present in remaining species), lateral surface of metapterigoid channel triangular (vs. rounded in remaining species), posterior area of contact between cleithrum and coracoid ventrally expanded (vs. straight in remaining species). Description. Morphometric and meristic data summarized in Table 1. Dorsal profile of body slightly convex from tip of snout to vertical through dorsal-fin origin; concave, nearly straight from that point to caudal-fin origin. Ventral profile of body straight from snout tip to caudal-fin origin. Ventral surface from tip of snout to urogenital papillae lacking plates, except for few small plates at pectoral- and pelvic-fin origins. Greatest body width at pectoral girdle. Trunk strongly keeled; five rows of keels; each one along each body plate series. Greatest body depth at dorsal-fin origin, body most slender at caudal peduncle. Head tall, pointed anteriorly, somewhat triangular in dorsal view; snout and cheek completely covered by numerous small plates, except for small naked area on tip of snout. Snout very pointed in dorsal view. Nasal bone rectangular, thin and elongate (Fig. 3). Frontal bone short, slightly contacting nares anteriorly and orbit posteriorly (Fig. 3). Anterior margin of frontal short, reaching posterior margin or half nare length (Fig. 3). Parietosupraoccipital enlogate, its posterior edge narrow, with V-shaped crest (Fig. 3). Sphenotic short, not contacting IO 6, with conspicuous odontodes (Fig. 3). Orbit small to moderate in size (9,6–16,4% HL), positioned dorsolaterally. Iris with small, dorsal flap over pupil. Pterotic-supracleithum short, with few fenestrae, its anterior process contacting a small region of posterior margin of orbit. Posterior area of pterotic-supracleitrhum with one or two small sized plates. Infraorbital series with 8 pores. Infraorbital 4 widely contacting posterior margin of orbit. Infraorbital 6 associated with only the posteroventral margin of orbit. Lateral line pores restricted to hypural plate. Mouth moderate in size, nearly as long as wide. Lips large, covered with papillae; size of papillae decreasing towards posterior margin of lower lip; central buccal papilla absent or little developed. Upper lip folded over itself. Maxillary barbel short; base of barbel united to lips, with free tip. Lower lip not reaching anterior margin of coracoid. Medial end of premaxillary teeth curved inwards. Premaxillae and dentary narrow and elongate. Dentary strongly curved inwards. Teeth slightly thick, well-developed, with long crown and large lateral cusp; its distal edge slightly curved inwards. Four to five pairs of predorsal plates. Cheek plates eversible, with hypertrophied odontodes. Dorsal-fin rays i, 8, pterygiophores located posterior to neural spines of vertebral centra 6–17. Dorsal-fin base very long, its length equals to 12 dorsal plates, reaching pre-adipose plate; connected to adipose fin by thick membrane. Dorsal-fin spinelet V-shaped with locking mechanism. Eight furcate neural spines supporting dorsal fin. Pectoral and pelvic fins well developed, medial portion conspicuously expanded relative to base; distal margin rounded. Pectoral-fin rays I, 6; unbranched ray covered with well-developed odontodes. Tip of adpressed pectoral fin almost reaching vertical through medial, unbranched, pelvic-fin ray. Pelvic-fin rays i, 5; pelvic-fin spine reaching vertical through anal-fin base when adpressed. Anal-fin rays i, 4, located posterior to haemal spines of vertebral centra 14–17. Caudal fin i, 14, i, truncate; caudal fin-ray filaments present in juveniles; supracaudal plates 7. Three to five (usually four) procurrent caudal-fin rays. Total vertebrae 29, precaudal 12. Sixth rib strongly thickened, remaining ribs slender. Color in life. Dorsal surface of trunk pale brown with median dark blotches that might be faint in juveniles and some adults; dark blotches anostomosing to form continuous zigzag bands alongside longitudinal keels in most specimens. Head without well-defined spots or blotches. Ventral surface pale, sometimes with some few faint spots in the abdominal region; spots in general absent in most specimens. All fins with orange or almost red color, at least in the unbranched fin-rays; more evident in the dorsal and caudal unbranched fin-rays. Juvenile specimens (in most cases) with dorsal and caudal fin almost completely faint orange without dark blotches. Color in alcohol. Specimens in alcohol usually exhibit the same color pattern when live, but in most cases the orange coloration of fins and blotches on body are inconspicuous and faint. Distribution. Pseudacanthicus pitanga probably occurs throughout the median and lower rio Tocantins. The species was recorded in the lower Tocantins river basin, at Serra dos Carajás, Tucuruí and Cametá, Pará state, and median Tocantins river basin, between São Salvador and Lajeado, Tocantins state (Fig. 4). Fisheries and economic importance. Because of its flashy and beautiful color pattern, the species of Pseudacanthicus, although not formally described, are very well known by local fishermen and the aquarist community, being an economic resource in some cases. Specimens of Pseudacanthicus pitanga, like other ornamental species, are exported to several countries worldwide, especially in Europe and the U.S.A., which has enabled many aquarists to breed them (E. Bertelsen, pers. comm.). Pseudacanthicus pitanga is economically important in the aquarium trade as an ornamental fish. The ornamental fish exploration has been a common practice in lower Tocantins in the Marabá region, and P. pitanga is recognized in the L number aquarist system as L024 (Schraml & Schaefer, 2004). Ornamental fishes are usually captured by diving with the aid of an air compressor, a collecting technique that is very common in ornamental fish exploration centers, such as in Marabá (Tocantins), Altamira (Xingu), and Santarém and Itaituba (Tapajós) (more about capture techniques in Sousa & Birindelli, 2009). Etymology. The specific epithet pitanga derives from Tupi-Guarani, meaning red, in allusion to the color of fins. An adjective.Published as part of Chamon, Carine C., 2015, Pseudacanthicus pitanga: a new species of Ancistrini (Siluriformes: Loricariidae: Hypostominae) from rio Tocantins Basin, North Brazil, pp. 309-320 in Zootaxa 3973 (2) on pages 310-314, DOI: 10.11646/zootaxa.3973.2.6, http://zenodo.org/record/23242
FIGURE 5 in A new species of driftwood catfish Centromochlus Kner, 1858 (Siluriformes Auchenipteridae, Centromochlinae) from Tocantins-Araguaia River drainage
No full textFIGURE 5. Centromochlus akwe in dorsal (A), lateral (B) and ventral (C) views; UNT 12676, 56.24 mm SL, Crixás River, tributary of the Tocantins River, Brejinho de Nazaré, Tocantins State, Brazil.Published as part of Coelho, Fernanda L., Chamon, Carine C. & Sarmento-Soares, Luisa M., 2021, A new species of driftwood catfish Centromochlus Kner, 1858 (Siluriformes Auchenipteridae, Centromochlinae) from Tocantins-Araguaia River drainage, pp. 149-165 in Zootaxa 4950 (1) on page 156, DOI: 10.11646/zootaxa.4950.1.8, http://zenodo.org/record/464356
Centromochlus akwe Coelho & Chamon & Sarmento-Soares 2021, new species
No full text<i>Centromochlus akwe</i>, new species <p>(Figure 1, Table 1)</p> <p> <b>Holotype</b>. MNRJ 51961, 61.0 mm SL, Javaés River, Ilha do Bananal, Pedral da Sambaíba, Pium, Tocantins, Brasil. 10°00’01”S, 50°01’29”W, 16 Sep 2017, Chamon, C. C. <i>et al</i>.</p> <p> <b>Paratypes</b>. All from Brazil. Tocantins State, Tocantins-Araguaia River basin basin. UNT 10879, 2, 39.1– 47.5 mm SL, rio Araguaia, Ananás, 6°7’12” S, 48°18’3” W, 8 Dec 2009, Marques, E. E. <i>et al</i>. UNT 5846, 1, 44.8 mm SL, rio Areias, Porto Nacional, 10° 50’ 30” S, 48° 23’ 35’’ W, 12 Dec 2000, Marques, E. E. <i>et al</i>.</p> <p> UNT 12676, 50, 42.2–68.3 mm SL, rio Crixás, Brejinho de Nazaré, 11°31’11”S, 48°34’21” W, 4 Nov 2010, Marques, E. E. <i>et al</i>. UNT 14211, 1, 71.3 mm SL, rio Tocantins, Porto Nacional, 10°43’15.”S, 48°25’14”W, 3 Feb 2011, Marques, E. E. <i>et al</i>. UNT 14255, 20, 17.5–47.5 mm SL, rio Santo Antônio, Sucupira, 11°57’48”S, 49 o 00’13”W, 10 May 2010, Marques, E. E. <i>et al</i>. UNT 15983, 1, 52.1 mm SL, rio Palma, Arraias, 12°21’44”S, 47°5’59”W, 24 Jan 2009, Aloisio, G (Consultoria CTE Engenharia). UNT 17391, 77, 3. 79–61.0 mm SL, collected with the holotype. UNT 17716, 1, 66.9 mm SL, rio Tocantins, Porto Nacional, 10°43’15”S, 48°25’14” W, 17 Aug 2007, Marques, E. E. <i>et al</i>.</p> <p> <b>Diagnosis</b>. The new species is diagnosed among Centromochlinae by having a vermiculated color pattern on the dorsum (<i>vs</i>. dorsum uniform in all Centromochlinae, except <i>Tatia brunnea</i>, <i>T. dunni</i>, and <i>T. meridionalis</i>). The new species is distinguished from these three aforementioned species by having eye ventrolaterally displaced on head in a way that almost the entire eye is visible in ventral view (<i>vs</i>. eye displaced dorsolaterally and not visible in ventral view). The new species is included in <i>Centromochlus</i> by sharing all the derived features for the genus, such as the ventrolateral position of eye socket; a sphenotic notched for the exit of infraorbital canal; and posterior serrations along pectoral-fin spine numerous (mentioned by Sarmento-Soares & Martins-Pinheiro, 2020: 127 to diagnose <i>Centromochlus</i>). The new species is diagnosed from congeners by having the pectoral-fin spine with dark bars, alternating with light bars (<i>vs</i>. pectoral-fin spine with light and uniform color in <i>all Centromochlus</i>). It is further distinguished from its congeners (except <i>C. carolae</i>) by the ventral surface of head moderate to largely pigmented (<i>vs</i>. ventral surface of head unpigmented in <i>C. heckelii</i>, <i>C. existimatus</i>, <i>C. orca</i>, <i>C. musaicus</i>, <i>C. schultzi</i> or with few scattered dark chromatophores in <i>C. macracanthus</i> and <i>C. melanoleucus</i>). It is distinguished from <i>C. carolae</i> by the presence of vermiculated color pattern or scattered chromatophores on lateral surface of the body that extends to the caudal peduncle (<i>vs</i>. lateral surface of the body with distinct demarcation between dark and light areas continuous posteriorly onto the caudal peduncle whereas the dark pigmentation extends nearly to the ventral midline in <i>C. carolae</i>), by lacking dark large and rounded blotches over a pale background on head and trunk (<i>vs</i>. present in <i>C. schultzi</i>); and by the smaller length of the dorsal-fin spine (18.1–27.1% of SL <i>vs</i>. more than 27% of SL in <i>C. macracanthus, C. heckelii, C. existimatus</i>), and pectoral-fin spine (24.2–32.2% of SL <i>vs.</i> more than 33% of SL in <i>C. macracanthus, C. heckelii, C. existimatus</i>).</p> <p> <b>Description.</b> Morphometric data presented in Table 1. Small-sized species, largest known specimen 61.0 mm SL (MNRJ 51961). Compact body. Anteriorly depressed head. Dorsal profile of head longer than broader. In lateral view, ventral profile of head and body approximately straight, profile slightly convex to slightly concave between anal fin and caudal fin. Greatest body width at pectoral-fin origin. Greatest body depth at dorsal-fin origin. Head covered with thick skin (making obscuring outline of cranial roof bones); eye ventrolateral; small terminal mouth, with rictus well-developed; snout margin rounded in dorsal and lateral views; anterior nostril tubular, located at anterior border of snout; posterior nostril limited anteriorly by skin flap; transverse distance between anterior nostrils less than that between posterior ones. Maxillary barbel elongate, reaching approximately vertical through dorsal-fin origin; Very short inner and outer mental barbels, not reaching the ventral edge of eye; bases of outer and inner barbels side by side, equidistant between inner and outer. Posterior process of cleithrum moderately long exceeding vertical through origin of dorsal fin.</p> <p>Dorsal fin I,5 dorsal-fin spine shorter than first branched ray; serrations on anterior and posterior faces of dorsalfin spine well-developed, anterior face with 19–25 serrations, posterior face with 18–20 serrations; first branched ray elongated, subsequent branched rays gradually decreasing in size; dorsal fin with truncated convex margin (n = 19). Adipose fin small 3.7–7.0% SL (n = 19), with free posterior margin. Pectoral fin I,4; pectoral-fin spine large, tip reaching pelvic-fin origin, when adpressed, anterior margin with 31–23 antrorse serrations, posterior margin with 18–26 retrorse serrations; serrations of anterior and posterior margins larger towards distal tip; pectoral-fin spine longer than subsequent rays; pectoral fin margin truncated (n = 19). Pelvic fin i,6; origin in the posterior half of the body; first branched ray longest, subsequent rays progressively smaller; distal margin of pelvic-fin approximately round. Anal fin iii,7 (n = 19); Anal-fin origin posterior to posterior margin of pelvic fin, its origin beyond posterior third of the body; last unbranched-ray and first branched-ray elongate; distal margin rounded. Caudal fin i,7–8,i; forked, with rounded lobes; dorsal and ventral lobes of equal size; 16 upper and 14 lower procurrent rays (n = 19).</p> <p>Anterior margin of cranium (Fig. 2) with mesethmoid wide and short; premaxillae with synchondral articulation to each other; anterior cranial fontanel narrow and ovoid, with two openings delimitated by mesethmoid and frontals; posterior cranial fontanel completely closed. Nasal ossified, short and tubular situated between mesethmoid cornua and lateral ethmoid. Lateral ethmoid not forming the dorsal surface of cephalic shield. Autopalatine rod-like, oriented almost parallel to longitudinal axis of body; maxilla slightly elongated; vomer arrow-shaped with short anterolateral processes. Jaws of equal size; premaxilla and dentary slender, each with two or three rows of conical teeth. Anterior nuchal plate absent; middle nuchal plate wide and with deeply concave lateral margins; posterior nuchal plate short, projected laterally, with rounded tips. Epiotic process small, not visible in dorsal view. Hyomandibula slightly more elongated than broad and forward projected, connected to quadrate by an interdigitated suture and cartilaginous tissue. Quadrate trapezoidal in shape and anteriorly connected to hyomandibula and posteriorly connected to metapterygoid by suture and cartilage. Metapterygoid trapezoidal in shape, connected to quadrate by suture; preopercle ventrally elongated and situated dorsally to quadrate and hyomandibular; preopercular canal exiting on anterior portion of pterotic. Opercle laminate and triangular (Figure 3). Hyoid arch with urohyal moderate in size, dorsal and ventral hypohyal associated to urohyal and relatively with the same size; anterior ceratohyal well developed, posterior ceratohyal smaller than anterior one; branchiostegal rays associated to hyoid arch, six branchiostegal rays, four slender rays associated with anterior ceratohyal, two flattened rays with posterior ceratohyal (Figure 4A). Branchial (gill) arches with basibranchial 2 elongated anteriorly, slightly separated from basibranchial 3; basibranchial 3 shorter, forming osseous rod; basibranchial 4 large, flattened and cartilaginous; basibranchial 2 bordered laterally by cartilaginous head of hypobranchial 1; basibranchial 3 between cartilaginous head of hypobranchial 2 and hypobranchial 3; basibranchial 4 bordered laterally by cartilaginous head of ceratobranchial 4 and caudally by cartilaginous head of ceratobranchial 5. Hypobranchial 1 hourglass-like, with anterior edge slender and posterior edge triangular; hypobranchial 2 mainly ossified, trapezoidal; hypobranchial 4 absent. Five ceratobranchials, all supporting single row of rakers; fifth ceratobranchial expanded posteromedially to support lower pharyngeal toothplate bearing short conical teeth. Four epibranchials, all supporting single row of few rakers, close to articulation with ceratobranchials. Epibranchials 1 and 2 rod-like; epibranchial 3 with posterior uncinate process; epibranchial 4 with laminar extension. Pharyngobranchials 1 and 2 absent; pharyngobranchial accessory cartilage somewhat ellipsoid placed between anteromedial cartilaginous tips of epibranchials 1 and 2; pharyngobranchial 3 elongate, ossified, with expanded posterior border; pharyngobranchial 4 ossified, shaped as a half-circle. Upper pharyngeal tooth plate bearing conical teeth, supported by pharyngobranchial 3 and 4, and also epibranchials 3 and 4 (Figure 4B).</p> <p>Eleven ribs ribs adhered to vertebrae 6 added to vertebrae 6–17, becoming progressively smaller and progressively smaller later. Total number of vertebrae 33 (n= 5), observed in cleared and stained specimens (c & s) and from radiographs.</p> <p> <b>Color in alcohol.</b> Head and trunk countershaded. Dorsal surface of head with dark dumbbell-shaped blotch from anterior naris to midlength of middle nuchal plate, with clear area above hyomandibula. Posterior portion of middle nuchal plate and posterior nuchal plate clear (tan). Posttemporal-supracleithrum and posterior process of cleithrum also clear, tan. Opercular series with dark pigment (colored as lateral face of trunk).</p> <p>Specimens from Javaés River with dorsal surface of trunk with vermiculated dark blotches. This pattern is continuous on the lateral surface above the lateral line, and on the lateral face of the caudal peduncle. Lateral face of trunk below lateral line and in front of caudal peduncle with irregularly-shaped and erratically-distributed dark blotches in some specimens. Specimens from Tocantins River (Figure 5) with vermiculation restricted to dorsum and around nuchal shield, and lateral face of trunk, including caudal peduncle with uniformly distributed melanophores, which become sparser towards ventrum.</p> <p>Ventral portion of head anterior to pectoral girdle and ventral portion of trunk posterior to pelvic fins marbled with dark blotches in most specimens (paler with uniformly distributed melanophores in others). Ventral surface of head and trunk from anterior margin of pectoral girdle to pelvic-fin bases completely pale. Dorsal, pectoral and caudal fins with dark transverse bands, sometimes inconspicuous in specimens preserved longer. Pelvic, anal and adipose fins hyaline. Caudal fin with background covered with large dark and rounded blotches that reduce in size from the base to distal edge.</p> <p> <b>Color in life</b>. Color in life almost dark gray with vermiculated pattern described in alcoholic specimens (Figure 6).</p> <p> <b>Sexual Dimorphism</b>. In nuptial males, anal-fin rays joined together forming single structure with rigid triangular shape with elongated distal tip retrorse spines structure (distal edge of anal fin thinner than the proximal edge) and pointed to posterior region of the body. Female and immature specimens have anal-fin rays separate, obliquely oriented, with distal tip rounded and with the almost the same width as the proximal border (Figure 7).</p> <p> <b>Distribution</b>. <i>Centromochlus akwe</i> is known from Tocantins-Araguaia River basin. It was reported from the upper and middle stretches of the Tocantins River; and in median and lower portions of the Araguaia River basin, at Javaés River (Ilha do Bananal) and at Araguaia River near the confluence to the Tocantins River (Figure 8).</p> <p> <b>Ecological notes</b>. Some specimens of <i>Centromochlus</i> from the Javaés River (Araguaia system) were collected in recent expeditions. The new species was found hidden in crevices within laterititic bedrock substrate covered by alluvial sediment, typical of the median portion of the Araguaia River basin (Figure 9). The specimens were manually collected and sometimes it was necessary to break the rocks to remove specimens that were hidden. The laterite is a geomorphological formation that originates from the weathering of lateritic crusts that cover the geological units, and it is common at the middle and lower rio Araguaia stretches (Latrubesse & Stevaux, 2002). In this type of environment were collected several species of Siluriformes that occur collected syntopically with the new species: such as <i>Centromochlus schultzi</i>, <i>Tatia intermedia</i>, <i>Auchenipterichthys longimanus</i> (Auchenipteridae) <i>Rhinodoras boehlkei</i>, <i>Platydoras armatulus</i> (Doradidae), <i>Rhamdia quelen</i> (Pimelodidae), <i>Leporacanthicus galaxias</i>, <i>Peckoltia vittata</i>, <i>P. sabaji</i>, <i>Parancistrus aurantiacus</i>, <i>Pseudacanthicus</i> sp., and <i>Spectracanthicus javae</i> (Loricariidae) (Chamon <i>et. al</i>., 2018). The sampling effort to collect the specimens were made in the twilight and daytime, with most specimens collected during the morning. At periods of capture, the collected specimens were in lethargic condition.</p> <p> <b>Etymology.</b> The specific name is in honor to the Akwê (Xerente self-denomination) indigenous people. The Akwê people were previously distributed throughout the middle and upper Tocantins River basin. Since the colonization of the indigenous territories in the so-called “Capitania de Goiás ” (in the 18th century), the Akwê-Xerente and other ethnic groups have been losing their territory and being decimated. Since the 19th century, the Akwê- Xerente have resisted conflicts with squatters and farmers, leading to a drastic reduction of their vast territory, now restricted to the city of Tocantínia, north of Palmas City (Instituto Socioambiental, ISA).</p> <p> <b>Conservation status</b>. <i>Centromochlus akwe</i> is known from the Javaés River, Araguaia system, and for the upper and middle stretches of the Tocantins drainage. In the Araguaia system, there is no major threats to the species. Although <i>C. akwe</i> was abundant at the sampling points, in both middle and upper stretches of the Tocantins River, there are at least two dams (UHEs Lajeado and Peixe Angical) that may have affected the new species. According to GeoCAT analysis its Extent of Occurrence (EOO) is 19,111; 132 km 2, what suggests that the species could be Vulnerable (VU), however, there was no more capture effort since 2010, thus we suggest that <i>C. akwe</i> should be categorized as deficient data (DD) according to the International Union for Conservation of Nature categories and criteria (IUCN, 2020).</p> <p> <b>Remarks</b>. Almost all the specimens from the middle Tocantins River in UNT collections were previously misidentified as <i>Centromochlus</i> cf. <i>punctatus</i> (<i>Tatia punctata</i>). A comparison with <i>Tatia punctata</i> (Mees 1974), a species described from Guiana shield rivers, revealed a similar color pattern. The new species is promptly distinguished from <i>T. punctata</i> by having two openings in the cranial fontanel (vs. single opening in <i>T. punctata</i>) and by the last branched ray of the modified anal fin of nuptial males, slightly shorter than penultimate ray in the new species (vs. last ray rudimentary in <i>T. punctata</i>).</p>Published as part of <i>Coelho, Fernanda L., Chamon, Carine C. & Sarmento-Soares, Luisa M., 2021, A new species of driftwood catfish Centromochlus Kner, 1858 (Siluriformes Auchenipteridae, Centromochlinae) from Tocantins-Araguaia River drainage, pp. 149-165 in Zootaxa 4950 (1)</i> on pages 150-159, DOI: 10.11646/zootaxa.4950.1.8, <a href="http://zenodo.org/record/4643560">http://zenodo.org/record/4643560</a>
Characterizing affine C-semigroups
Full text linkLet C subset of N-p be a finitely generated integer cone and S subset of C be an affine semigroup such that the real cones generated by C and by S are equal. The semigroup S is called C-semigroup if C \ S is a finite set. In this paper, we characterize the C-semigroups from their minimal generating sets, and we give an algorithm to check if S is a C-semigroup and to compute its set of gaps. We also study the embedding dimension of C-semigroups obtaining a lower bound for it, and introduce some families of C-semigroups whose embedding dimension reaches our bound. In the last section, we present a method to obtain a decomposition of a C-semigroup into irreducible C-semigroups.The authors thank the referees for their helpful observations. The authors were partially supported by Junta de Andalucia research group FQM-366. The first author was supported by the Programa Operativo de Empleo Juvenil 2014-2020, financed by the European Social Fund within the Youth Guarantee initiative. The second, third and fourth authors were partially supported by the project MTM2017-84890-P (MINECO/FEDER, UE), and the fourth author was partially supported by the project MTM2015-65764-C3-1-P (MINECO/FEDER, UE)
Possible hyperdeformed band in (36)Ar observed in (12)C+(24)Mg elastic scattering
No full textFifteen strongly oscillating angular distributions of the elastic scattering of (12)C + (24)Mg at energies around the Coulomb barrier (E(c.m). = 10.67-16.00 MeV) are reproduced by adding five Breit-Wigner resonance terms to the l = 2, 4, 6, 7, and 8 elastic S matrix. The nonresonant, background elastic scattering S matrix S(l)(0) is calculated using the Sao Paulo potential. The J = 2, 4, 6, 7, and 8 (h) over bar molecular resonances fit well into a rotational molecular band, together with other higher lying resonances observed in the (16)O + (20)Ne elastic scattering. We propose that the presently observed, largely deformed molecular band corresponds to the hyperdeformed band, which has been found previously in alpha-cluster calculations, as well as in a new Nilsson model calculation. Systematic study of its possible clusterizations predicts the preference of the (12)C + (24)Mg and (16)O + (20)Ne molecular structure, in accordance with our present results.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)OTKA[K72357], Hungar
Illuminaçao Apologetica do retrato de Morteçor en que aparecem com mais vivas côres os erros do author do novo Methodo, e seu Apologista ...
No full textFecha sacada de la pág.2 y 159Sign.: A-V\p4\sError tipográfico de signatura : a B\b2\s llama B\b3\
K-theory for group C*-algebras
No full textThese notes are based on a lecture course given by the first author in the Sedano Winter School on K-theory held in Sedano, Spain, on January 22-27th of 2007. They aim at introducing K-theory of C*-algebras, equivariant K-homology and KK-theory in the context of the Baum-Connes conjectur
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