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FIGURE 2 in Nemesia arenifera (Scrophulariaceae), a new species from the Sandveld, Northern Cape Province, South Africa, and the lectotypification of N. viscosa
No full textFIGURE 2.—Known distribution of Nemesia arenifera, based on specimens at PRE and NBG. Specimens collected through the National Herbarium Plant Collecting Programme (2005–2011), •; other collections, Θ.Published as part of Bester, Stoffel P. & Steyn, Hester M., 2013, Nemesia arenifera (Scrophulariaceae), a new species from the Sandveld, Northern Cape Province, South Africa, and the lectotypification of N. viscosa, pp. 49-54 in Phytotaxa 126 (1) on page 53, DOI: 10.11646/phytotaxa.126.1.6, http://zenodo.org/record/508528
Acanthopsis HARV.
No full textKEY TO THE DIFFERENT TRICHOME TYPES ON LEAVES AND FLORAL BRACTS OF ACANTHOPSIS HARV.: 1a. Trichomes non-glandular....................................................................................................................... 2 1b. Trichomes glandular.............................................................................................................................. 5 2a[1]. Trichomes relatively thin-walled with a broad lumen (> ⅓ of cell diameter); uni- or multicellular; surface ornamented........................................................................................................................................... 3 2b. Trichomes thick-walled with a narrow lumen ( 250 µm); stalk 3-celled................................................................. Type G 6a[5]. Trichomes sessile or subsessile; stalk, if present, 1-celled................................................................. Type E 6b. Trichomes short; stalk 2 (or 3)-celled............................................................................................... Type FPublished as part of Steyn, Hester M. & Van Wyk, Abraham E., 2021, Taxonomic significance of trichomes in the genus Acanthopsis Harv. (Acanthaceae, tribe Acantheae), pp. 163-176 in Adansonia (3) (3) 43 (14) on page 166, DOI: 10.5252/adansonia2021v43a14, http://zenodo.org/record/509202
Nemesia viscosa E. Meyer ex Bentham 1836
No full text<i> <i>Nemesia viscosa</i> E.Meyer ex Bentham</i> (1836: 21) <p> <b>Type (designated here):</b> — SOUTH AFRICA. Northern Cape: Verleptpraam et ad fl. Gariep. [Annotation in different handwriting: On hills by the Orange River near Verleptpram, Little Namaqualand], (2817AA), September 1830, <i>Drège 3142a</i> (lectotype K000411170, scan!).</p> <p> <i>Note</i>:—The K specimens were the only ones that could be traced. Two syntypes (<i>Drège 3142a</i> & <i>b</i>) are mounted together on the same sheet, each having its own label. One specimen (<i>Drège 3142a</i>) has mostly dehisced capsules but no flowers and the other has buds, but no mature flowers or capsules, therefore the syntype <i>Drège 3142a</i> is considered the better specimen representing the description in the protologue and is chosen here as the lectotype.</p>Published as part of <i>Bester, Stoffel P. & Steyn, Hester M., 2013, Nemesia arenifera (Scrophulariaceae), a new species from the Sandveld, Northern Cape Province, South Africa, and the lectotypification of N. viscosa, pp. 49-54 in Phytotaxa 126 (1)</i> on page 50, DOI: 10.11646/phytotaxa.126.1.6, <a href="http://zenodo.org/record/5085286">http://zenodo.org/record/5085286</a>
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Nemesia arenifera Bester & H. M. Steyn 2013, spec. nov.
No full textNemesia arenifera Bester & H.M.Steyn, spec. nov. (Fig. 1) Diagnosis:— Nemesia areniferae sp. nov. N. rupicolae Hilliard in Hilliard and Burtt (1986: 396) quoad labium inferum corollae in linea cum calcari portatum plusminusque ad pedicellum parallelum similis, sed floribus multo minoribus, luteis (non plerumque albis vel dilute roseis, dilute caeruleis vel malvinis), foliis anguste lanceolatis ad ellipticis vel oblongis, minute dentatis (non late ovatis, non manifeste dentatis). Ceterum, hae species bene distinctae distributione geographica: species nova littora incolens ad oras occidentales provinciae Northern Cape sed N. rupicola species montana rupes incolens in regione orientali Africae australis. Type: — SOUTH AFRICA. Northern Cape: Namaqualand District. Namaqua National Park, ca. 24.6 km NE of Koingnaas, 203 m, 30°01'13.2"S 17°25'35.1"E (3017 AB), 11 August 2011, M. Koekemoer 4202 (holotype PRE!; isotypes BOL!, K!, KMG!, NBG!) Description: —(All measurements are based on herbarium specimens). Annual, erect herb 40–300 mm high; stems simple or branching from base, lateral stems up to 100 mm long, square in cross-section, ridged because of decurrent leaf bases, often dark reddish, leafy. All parts of plant glandular pilose, except most of corolla, with spaced, transparent to whitish hairs, mostly ± patent, terete with exudate a little broader than hair itself. Leaves simple, opposite to subopposite or sometimes alternate near stem apex, sessile to shortly petiolate, decurrent on stem; leaves on short, lateral shoots tufted and appear congested and clumped together; lamina narrowly lanceolate, elliptical or oblong, often longer than internodes, 11–40 × 2–7 mm; base attenuate; apex mostly obtuse sometimes sub-obtuse, rarely acute; margins entire to sparingly dentate with 2–7 pairs of very small, narrowly deltoid teeth, usually in upper half. Bracts alternate, sessile, leaf-like, becoming smaller upwards. Pedicels up to 9 mm long, elongating and recurved or variously contorted when fruit matures. Calyx 5-lobed, spreading, 1.5–6.3 × 0.4–1.8 mm, weakly bilabiate with two lobes somewhat broader than the other three, oblanceolate to narrowly obovate or oblong; apex mostly obtuse some sub-obtuse, glandular pilose. Flowers axillary or in lax racemes up to 80 mm long. Corolla bilabiate, 3.8–8.3 × 1.9–6.5 mm, pale to bright yellow; upper lip 4-lobed, 3.9–5.1 × 2.4–3.8 mm, base a stronger yellow with faint magenta to maroon venation forming vertical streaks, continuing down into the tube, base ± perpendicular to margins, apex rounded to emarginate; two inner lobes slightly smaller than other two, semi-erect, oblong to ovate; two outer lobes oblong to elliptic, slightly spreading; lower lip with one lobe, widely obovate and emarginate or obcordate, 2.3–2.6 × 1.0– 3.3 mm, basal portion inflated into convex projecting palate; palate bright yellow, longitudinally grooved, glabrous; boss glabrous or slightly papillate, a stronger yellow than main part of corolla; tube> 0.5 mm long, pale yellow; hypocotyle (floor of corolla tube) 3.0– 3.3 mm long, sides invaginated to form a narrow channel, base of tube drawn out into a conical, backward-projecting spur, 1.8–4.4 × 0.2–1.4 mm, glabrous, bright yellow, held ± parallel to the pedicel. Stamens 4, lying in a shallow depression in upper inside surface of corolla tube; filaments of anticous pair 1.1–1.8 mm long, sigmoid, ± straight in middle; posticous filaments 0.6–0.7 mm long, ± straight except at base; anthers 0.5–0.6 mm long, each pair strongly coherent. Ovary ovoid, 2.0–2.5 × 1.0– 1.5 mm, glabrous, laterally compressed; style stout, straight, 0.4–0.5 × 0.3–0.4 mm, compressed contrary to the ovary, apex wider than base, lying between anther pairs; stigma simple, oval or slightly triangular in cross-section, stigmatic surface finely papillate, darker than style. Capsules ± oblong-ovoid in outline, 4.5–11.0 × 4.0–5.0 mm, laterally compressed contrary to septum, apex emarginate to bilobed, lobes rounded to acute with very steep angle between them, apical incision 1.0– 2.3 mm deep. Seeds widely ovate, 1.2 × 0.3–1.7 mm, light brown, verruculate, winged; wing membranous and fluted. Flowering & fruiting: August–September. Distinguishing characters: — Nemesia arenifera does not resemble any known Nemesia species from southern Africa. Diagnostic characters include the erect habit, small yellow flowers with the spur carried parallel to the pedicel and the viscid indumentum. It differs from N. viscosa in habit, leaf and floral characters (Table 1). In N. arenifera and N. rupicola the lower lip of the flower is in line with the spur and parallel to the pedicel, however, these species differ significantly from each other in habit, distribution, leaf and various floral characters (Table 1). Etymology: —The specific epithet, arenifera, refers to the preference of this species for deep, loose, sandy soils. The glands that cover the whole plant surface exude a sticky substance and sand adheres to this so the plant is literally “covered in sand”. Distribution and habitat: — Nemesia arenifera seems to be restricted to the arid coastal dune systems from Alexander Bay in the north to Groen River Mouth in the south (Fig. 2) at an elevation of less than 300 m. Current distribution records suggest it to be a Northern Cape, coastal endemic. It occurs in deep, loose aeolian sand, ranging from white through yellow to red. This species is known only from the Namaqualand Sandveld Bioregion (vegetation types SKs1, SKs7, SKs8) and Sand Fynbos Bioregion (vegetation type FFd1) within the Succulent Karoo and Fynbos Biomes respectively (Mucina & Rutherford 2006). Winter rains are predominant, falling mainly between May and August with an average of 50–114 mm per annum. Dense fog, especially in winter, contributes to the precipitation and frost is very rare. Conservation status: — Nemesia arenifera currently has a threat status of LC (Least Concern) (L. von Staden pers. comm.). Although this species has a restricted range (extent of occurrence of 2 767 km ²), it is fairly common (known from more than 10 locations), and subpopulations can be large during years of above average rainfall. Some subpopulations near the coast may be declining due to habitat loss because of mining. However, only about 3% of this species’ range is currently transformed, and mining is unlikely to be a severe threat. Additional specimens examined (paratypes): — SOUTH AFRICA. Northern Cape: Namaqualand, Alexander Bay, Visagiesfonteinkop at base of granite outcrop (2816DC), 26 August 1978, A. Le Roux & M. Ramsey 212 (PRE!); In arenosis prope Port Nolloth. In Namaland Minore, 50 ft, (2916BD), August 1883, H. Bolus in Herb. Normale Austro-Africanum 650 (PRE!); Namaqualand District, between Koingnaas and Kleinzee, on turn-off towards the coast where the new Nuclear Powerstation is planned, 56 m, 29°49'14"S 17°06'10"E (2917CC), 11 August 2007, S.P. Bester 7928 (PRE!); Namaqualand, Sandveld, Farm: Zonnekwa 326, plateau W of Sonnekwa homestead on a plateau dune (2917CC), 21 August 1993, A. le Roux 4524 (NBG, scan!); Namaqua National Park, Farm: Taaiboschvlakte 337, ± 13.4 km NNW of Riethuis homestead, 189 m, 29°59'56.4"S 17°23'22.9"E (2917CD), 15 August 2009, S.P. Bester 9488 (PRE!); Namaqua National Park. Farm: Taaibosch Vlakte 337, 22.6 km NW of Soebatsfontein and 25.5 km NNE of Koingnaas, 211 m, 29°59'29"S 17°24'31"E (2917CD), 13 August 2007, S.P. Bester 7968 (PRE!, KMG!, KSAN!, MO!); Namaqualand District, between Koingnaas and Kleinzee, 43 m, 30°06'54" S 17°12'56" E (3017AA), 10 August 2007, S.P. Bester 7879 (PRE!); Namaqualand National Park, Farm: Roodelaagte 476, ± 18.4 km NE of Hondeklip Bay, 131 m, 30°11'48.6"S 17°24'22.8"E (3017AB), 18 August 2009, S.P. Bester 9534 (PRE!); Namaqua National Park, Farm: 477, Jantjieskop portion, ± 15.6 km directly NE of Hondeklipbaai, 185 m, 30°14'25.0"S 17°24'38.0"E (3017AB), 19 August 2009, S.P. Bester 9544 (PRE!); 100 m from Koiingnaas-Hondeklip Bay main road at Swartlintjies River (3017AB), 27 August 1986, A. le Roux & J.W. Lloyd 359 (NBG, scan!); Namaqualand National Park, Farm 477, ± 400 m W of Taaiboschduin homestead and ± 15.8 km NE of Hondeklip Bay, 177 m, 30°15'32.7"S 17°25'40.2"E (3017AD), 17 August 2009, S.P. Bester 9508 (KSAN!, PRE!); Namaqua National Park, Farm: Avontuur 488, ± 10.2 km directly SE of Hondeklipbaai, 129 m, 30°21'19.9"S 17°22'24.5"E (3017AD), 19 August 2009, S.P. Bester 9571 (PRE!); Namaqua National Park, Farm: Kanoep 491, ± 23.8 km SE of Hondeklip Bay, 30°28'54.0"S 17°26'14.5"E, 47 m, (3017AD), 21 August 2009, S.P. Bester 9631 (NBG!, PRE!); Namaqua National Park. Farm: Diknek 486, 56m, 30°22'59"S 17°27'31"E (3017AD), 7 September 2010, S.P. Bester 10061 (PRE!); Namaqua National Park, Farm: Avontuur 488, S of Wallekraal-Hondeklipbaai road, 130 m, 30°21'16"S 17°22'20"E (3017AD), 11 August 2006, H.M. Steyn 967 (PRE!); Namaqua National Park, West Coast section, ca. 15 km North of Groenrivier, Kawass Annex area, 27 m, 30°44'12"S 17°31'35"E (3017DA), 19 August 2005, S.P. Bester 5950c (PRE!); Groen Rivier Mouth near lighthouse (3017DC), 25 August 2002, P. Goldblatt & L.J. Porter 12115 (NBG, scan!).Published as part of Bester, Stoffel P. & Steyn, Hester M., 2013, Nemesia arenifera (Scrophulariaceae), a new species from the Sandveld, Northern Cape Province, South Africa, and the lectotypification of N. viscosa, pp. 49-54 in Phytotaxa 126 (1) on pages 50-53, DOI: 10.11646/phytotaxa.126.1.6, http://zenodo.org/record/508528
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