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FIGURES 13–14. Atopopus tarsalis egg. Fig. 12 in The nymph of Atopopus tarsalis Eaton, 1881 (Ephemeroptera, Heptageniidae): first description, ecology and behaviour
No full textFIGURES 13–14. Atopopus tarsalis egg. Fig. 12: general shape; Fig. 13: detail of the micropyle area.Published as part of Sartori, Michel & Derleth, Pascale, 2007, The nymph of Atopopus tarsalis Eaton, 1881 (Ephemeroptera, Heptageniidae): first description, ecology and behaviour, pp. 25-32 in Zootaxa 1586 on page 29, DOI: 10.5281/zenodo.17845
Kilariodes marifae Sartori & Derleth 2010, sp. nov.
No full textKilariodes marifae sp. nov. Material examined. Holotype: 1 female larva, Indonesia - East Kalimantan, Malinau Basin, Langap Sud (1997-petak 6), Belakau stream, tributary of the Rian River, 116°30'26''E / 3°04'04''N; 100 m. a.s.l., 20.04.2001, (B0113), P. Derleth & M. Sartori [MZL] Paratype: 1 female larva, same data as holotype (partially mounted on microscopic slide) [MZL] Nymph. Body length at least 4.6 mm for female sub mature nymphs. Cerci slightly shorter than body length. General colouration of head, thorax and abdomen medium brown, without specific patterns, sternites yellowish brown; legs uniformly yellowish. Antennae ca 1.5 longer than head width. Labrum (Fig. 7) ca 2.75 wider than long (measurement in the sagittal plan), anteromedian emargination with irregular denticles (Fig. 8); dorsal side with a sub distal row of long setae, scattered long setae on the ventral side. Left and right mandibles (Figs 9–10) with a hump in the middle of the outer margin, bearing a dozen of very long and thin simple setae; a row of long setae on the dorsal face, some feathered in the distal half; outer and inner incisors elongated, each constituted of three teeth; prostheca more developed on the left mandible (Fig. 9); a row of 6–7 long and thin setae below the mola of the right mandible (Fig. 10). Maxillae with crown of setae covering almost the apex of the galea (Fig. 11). Maxillary palp with segment 1 the longest, two times longer than wide, segments 2 and 3 subequal in length, each ca 0.75 times the length of segment 1; outer margin of segment 3 with long and thin setae, especially at apex (Fig. 12). Superlinguae of hypopharynx with setae on dorsal margin not reaching the apex (Fig. 14). Labial palp (Fig. 15) with segment 1 stout, 1.3 longer than wide, inner margin strongly convex, outer margin with a row of long and pointed setae; segment 2 slighly longer than segment 1, with ca 6 long and pointed setae on proximal part of outer margin; segment 3 ca 0.6 times the length of segment 2, rounded at apex. Femora (Fig. 16) with a row of stout and pointed setae on outer margin, ending on the dorsal face in distal part; inner margin with scattered short and pointed setae; dorsal face without any setae except 4–6 scattered long and pointed setae on proximal part. Inner margin of tibiae with stout, pointed and feathered setae, outer margin with few thin setae. Tarsal claw (Fig. 17) moderately hooked, with a single row of 11–13 denticles, the distal 5–7 larger than the proximal ones. Gill I the smallest, ca 0.6 times the length of gill IV. Subanal plate regularly rounded. Cerci with first 10–12 segments with a posterior whorl of denticles, more distal ones without such a whorl. Male and female adults unknown. Etymology. This species is dedicated to Mrs Marie-France “Marif” Decker Leonnard (Pully, Switzerland), great friend of us. Distribution and ecology. K. marifae is one of the rarest mayfly species found in our study site; it has been sampled a single time on a single stream which flows in an area which was recently logged. Water temperature during sampling was 26.1 °C, speed flow around 0.2 m /s, water depth of 0.26 m, and substrate composed mainly by gravels (70%) and cobbles (15%). Other mayfly species collected at the same time included Polyplocia campylociella Ulmer, 1939, Potamanthus (Stygifloris) sabahensis (Bae, McCafferty & Edmunds, 1990), Atopopus tarsalis Eaton, 1881, Hyrtanella pascalae Jacobus & Sartori, 2004, Dudgeodes hutanis Sartori, 2008, Derlethina eloisae Sartori, 2008 and Isca lea sp. nov.Published as part of Sartori, Michel & Derleth, Pascale, 2010, The dipterous Leptophlebiidae of Borneo (Insecta, Ephemeroptera), pp. 33-39 in Zootaxa 2490 on pages 36-3
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Benthic macroinvertebrates and logging activities : a case study in a lowland tropical forest in East Kalimantan (Borneo, Indonesia)
No full textAt the beginning of the 21 century, the conservation of biodiversity and the sustainable use of natural resources remains a matter of concern. Within this framework, the aim of this research was to study the effects of logging activities on ecological water quality indicators in a tropical forest. The study was undertaken at both local (species/habitat) and landscape (watershed) scales. The study took place on Borneo Island, in East Kalimantan province (Indonesia), in a state-owned timber concession, on an area of 85 km2. In order to study the impact of logging activities at landscape scale, five satellites images (1991, 1997, 1999, 2000 and 2001) were examined. The ecological water quality was evaluate by a biological and a habitat assessment, which were performed at each stream reach. The biological assessment constituted in collected benthic macroinvertebrates. This protocol was conducted at 23 sampling sites on headwater streams in order to compare the impacts of logging in logged area versus unlogged area. Logged area were grouped by the time interval after logging. We examined several groups: recently logged (during logging and until 6 months after logging), 1 to 3 years after logging and, 4 to 5 years after logging and relogged for a second time. Two field seasons occurred in June-August 2000 and April-May 2001. During this eight months time interval, most of the timber concession was relogged for a second time, as a result of the decentralisation process at government level. The research took four years and the following main results have been obtained. Logging activities at landscape scale were quantified by the total length of logging roads. This underlined the intensification of the logging activities from one satellite image to the other over the time (from 1991 to 2001). Vegetation classification and vegetation index (NDVI) could not be used to assessing the impact of logging activities on forest quality because of the homogeneous forest cover in the study site (no visible patches). Benthic macroinvertebrates and environmental variables were considered an ideal tool to assess the ecological water quality in the study site. Macroinvertebrates richness was high with 115 taxa mainly identified at family and sub-family level (genera for Ephemeroptera), but abundance was low (mean density of 770 individuals per square meter, ranging from 86 to 2130). Multivariate analysis highlighted that the size of the streams and the impact of logging activities played an important role in ordinating the samples. A co-inertia analysis demonstrated that benthic macroinvertebrates and environmental variables were found to be strongly related to each others. The main results indicated that macroinvertebrate density, richness, diversity, composition and functional feeding organisation responded to logging activities. During and six months after logging, macroinvertebrate density was higher and diversity indices were lower compared to the reference samples (unlogged situation). One to three years after logging were found to be the most disturbed situation, indicated, among other things, by an even lower diversity indices. Environmental variables responded to logging activities by: an increase in canopy opening, water temperature, amount in fine sediment and flow velocity and by a decrease in Fine Particulate Organic Matter (FPOM). The stream ecosystems seemed to recover 4 to 5 years after logging in absence of ongoing activities, density and diversity seemed similar but benthic macroinvertebrate composition is different compared to reference unlogged situation. Among the 115 taxa identified during the study, several were indicator taxa, meaning that they characterised the impact of logging activities at a given time. Indicator taxa were grouped in five categories: "open canopy" taxa (Platybaetis, Lepidoptera, Hydropsychinae); "sensitive" taxa (e.g. Caenodes, Limonidae, Potamanthus, Perlidae, Philopotamidae); "pulse" taxa (e.g. Psephenidae, Jubabaetis, Platybaetis, Megaloptera, Glossossomatidae) ; "recovery" taxa (e.g. Labiobaetis, Helicopsychidae, Platystictidae) and "adaptive" taxa (Diplectroninae, Simuliidae, Isca). A Tropical Stream Concept was proposed to take into account the paucity of shredders collected in the headwater catchment streams. The higher decomposition rate and terrestrial shredders provides the Fine Particulate Organic Matter as direct input from the washing out of the catchment during rainy events. In summary, macroinvertebrates can be considered excellent indicators, which were successfully used in this tropical environment for both objectives: they assessed biodiversity as an element of forest sustainability and they assessed disturbances due to logging activities, with the advantage to be indicative of recent and past events. Further research is proposed to test the identified indicator taxa to other regions in Borneo, to valid them and to prepare a simplified key to be used by local institutions as a tool for monitoring ecological water quality.GECO
Atopopus tarsalis Eaton 1881
No full text<i>Atopopus tarsalis</i> Eaton, 1881 <p> <b>Nymph.</b> Size: male, body length up to 12.3 mm, cerci length up to 14.8 mm; female, body length up to 14.9 mm, cerci length up to 15.5 mm.</p> <p>Head: Broader than the pronotum, antennae short, at most reaching the margin of the cephalic capsule. Hind margin smoothly concave, lateral emargination behind the eyes strongly developed (Fig. 1). Fore margin above</p> <p>Labrum expanded laterally, about 5 times broader than long, slightly bent backwards (Fig. 2). Anterior margin with a V-shaped incision densely covered with long and thin setae. Ventral surface with submarginal row of stout setae arranged in V-shape.</p> <p>Mandibles slender and elongated, outer margin densely and regularly covered with long setae. Left mandible with well developed inner incisor; outer incisor serrated on its entire inner face; tuft of 5–7 somewhat plumose setae below the inner incisor; 3–5 hair-like setae below the mola (Fig. 3). Right mandible with shorter inner incisor, ending with two setae-like teeth; outer incisor serrate on its inner face, except the apical fourth; tuft of 7–9 plumose setae below the inner incisor; tuft of numerous, short setae above the mola, and a row of 7–9 hair-like setae below it; mola ending posteriorly with a hook (Fig. 4).</p> <p>Ventral surface of the galea-lacinia covered with scattered simple setae; proximal dentiseta forked near apex; distal dentiseta composed of a bunch of forked and simple setae (fig. 5); crown of the galea-lacinia covered with 15–19 comb-shape setae, the median ones composed of ca 10–12 teeth; first segment of the maxillary palp with numerous long setae on its outer margin, and with scattered and thinner setae on its inner one.</p> <p>Lingua of hypopharynx thick and with a tuft of setae apically; superlingua well developed, outer margin folded one or two times, apex pointed and strongly bent backwards (Fig. 6).</p> <p>Labium with glossae widely separated by a large and angular emargination; inner face of glossae covered with long setae; paraglossae extended laterally, with rounded apex and slightly turned backwards.</p> <p>Thorax: Lateral margin of the pronotum rounded, without postero-lateral expansions; posterior margin slightly concave.</p> <p>Coxae increasing in size from the fore to the hind coxae, acuminated posteriorly.</p> <p>Legs unusually short and stout; ratio length/width of the fore, middle and hind femora ca 2.0, and ratio femur/tibia lengths ca 1.3 (Fig. 7). Dorsal margin of femora covered with long and stout setae, ventral margin with scattered small spine-like setae, increasing in number from the fore- to the hind femora; upper face covered with numerous small spine-like setae, rounded at the apex, slightly longer than wide. Dorsal margin of tibiae covered with long and thin setae, ventral margin with few spine-like setae. Tarsi with dorsal margin covered with long and thin setae, except the fore tarsi which bear only minute thin setae. Presence of a well developed spine-like seta on the ventro-distal part of the hind tarsi. Tarsal claws without apical denticle.</p> <p>Abdomen: Colour pattern very characteristic and as in Fig. 11. Abdominal sternite I with lateral sclerites quadratic to pentagonal, and reaching almost the posterior margin. Postero-lateral extensions increasing in size from sternite II to VIII (Fig. 8).</p> <p>Gills present on segments I–VII. Gill I attached dorsally and composed of a well developed tuft of fibrillae and a minute, almost invisible lamella (Fig. 9). Gills II–VI alike, attached laterally and composed of a lamella with well marked tracheation, and a tuft of purple fibrillae (Fig. 10). Gill VII with a well developed lamella but without fibrillae. All lamellae with some kind of strengthening subparallel to the outer margin.</p> <p>Posterior margin of the sternite IX of female nymphs slightly concave.</p> <p>Cerci and well developed terminal filament with whorls of spine-like setae, without hair-like setae.</p> <p> <b>Egg.</b> Shape ovoid, ca 110 μm x 75 μm (Fig. 13). Chorionic surface covered with small granulations (ca 1 μm in diameter), as well as with medium size knob-terminated coiled threads (KCT’s) approximately 2–3 μm in diameter. Two polar caps with numerous KCT’s of the same size as those on the other part of the chorion. Four micropyles situated in the equatorial area; margin of the micropyle with irregularly placed granulations (Fig. 14).</p> <p> <b>Material examined.</b> All the material listed below comes from the Island of Borneo and is deposited in the Museum of Zoology, Lausanne, Switzerland and in the Museum of Zoology, Bogor (LIPI), Indonesia.</p> <p> INDONESIA, <b>East Kalimantan</b>: Malinau Basin</p> <p> <i>Rian River tributaries</i></p> <p>Belakau, Langap Sud (1997-petak 6), 116°30'26''E, 3°,04'04''N, 13.06.2000 (B0110), Derleth, P., 10 nymphs; same locale but 0 5.07.2000 (B0111), Derleth, P., 7 nymphs; same locale but 20.04.2001, (B0113), Derleth, P. & Sartori, M., 10 nymphs; same locale but 0 7.07.2000, (0121), Derleth, P., 10 nymphs; same locale but 18.04.2001 (B0123), Derleth, P. & Sartori, M., 10 nymphs</p> <p>Ngayo, Langap Sud (1995), 116°31'11''E, 3°04'41''N, 14.06.2000 (B0410). Derleth, P., 5 nymphs; same locale but 0 8.07.2000, (B0411), Derleth, P., 12 nymphs;</p> <p>Ngayo, Langap Sud (1995), 116°31'15''E, 3°04'41''N, 12.07.2000. (B0421), Derleth, P., 12 nymphs</p> <p>Unnamed tributary, Langap Sud (1999-petak 24), 116°31'05''E, 3°01'40''N, 11.07.2000, (B1211), Derleth, P., 19 nymphs.</p> <p> <i>Seturan River tributaries</i></p> <p>Temalat (Sungai Guang), Seturan (1999-petak 39-40), 116°32'24''E, 3°00'10''N, 0 1.07.2000, (B0211), Derleth, P., 1 nymph; same locale but 27.03.2001, (B0213), Derleth, P., 2 nymphs;</p> <p>Seturan River main stream, Bulungan camp, 116°30'36''E, 3°00'20''N, 13.07.2000, (B0431), Derleth, P., 12 nymphs</p> <p>Tamalang, Seturan (2001-petak 57), 116°30'29''E, 2°59'22''N, 10.04.2001, (B0513), Derleth, P., 1 nymph;</p> <p>Bengahau, Seturan (2001-petak 57), 116°30'46''E, 2°59'22''N, 0 8.08.2000, (B0531), Derleth, P., 2 nymphs; same locale but 11.04.2001, (B0533), Derleth, P. & Feldmeyer, B., 7 nymphs</p> <p>Wok (Sungai Guang), Seturan (2000-petak 45), 116°33'29''E, 2°59'09''N, 16.06.2000, (B0611), Derleth, P. & Gattolliat, J.-L., 1 nymph;</p> <p>Wok (Sungai Guang), Seturan (2000-petak 45), 116°33'30''E, 2°59'11''N, 29.06.2000, (B0631), Derleth, P., 11 nymphs</p> <p>Wok (Sungai Guang), Seturan (2000-petak 44-45), 116°33'11''E, 2°59'12''N, 17.06.2000, (B0711), Derleth, P. & Gattolliat, J.-L., 8 nymphs; same locale but 0 5.04.2001, (B0713), Derleth, P. & Feldmeyer, B., 29 nymphs;</p> <p>Temalat (Sungai Guang), Seturan (2000-petak 43), 116°33'29''E, 2°59'29''N, 18.06.2000, (B0811), Derleth, P. & Gattolliat, J.-L., 10 nymphs; same locale but 16.08.2000, (B0812), Derleth, P., 11 nymphs; same locale but 16.04.2001, (B0813), Derleth, P., 29 nymphs; same locale but 21.06.2000, (B0821), Derleth, P. & Gattolliat, J.-L., 6 nymphs; same locale but 0 4.04.2001, (B0823), Derleth, P., 3 nymphs; same locale but 16.04.2001, (B0833), Derleth, P. & Sartori, M., 6 nymphs.</p> <p>Unnamed tributary, Seturan (unexploited), 116°33'29''E, 2°58'54''N, 24.04.2001, (B1413), Derleth, P., Sartori, M. & Feldmeyer, B., 1 male imago, 8 nymphs;</p> <p>Unnamed tributary, Seturan (unexploited), 116°33'30''E, 2°58'58''N, 26.04.2001, (B1423), Derleth, P. & Sartori, M., 2 nymphs.</p> <p> MALAYSIA — <b>Sabah:</b> Penampang River, Crocker Range National Park, 15.08.2003, (B2001), M. Whiting's lab., 5 nymphs.</p> <p> <b>Affinities.</b> The nymphs of <i>A. tarsalis</i> are more similar to those of <i>A. edmundsi</i> than to those of <i>A. tibialis</i> or <i>A. meyi</i> based on the similarities in the number of comb-like setae on the galea-lacinia, the shape of the coxae and the shape of the 9th sternite of mature females. Based on the figures present by Wang and McCafferty (1995), there are distinct differences between <i>A. edmundsi</i> and <i>A. tarsalis</i> in the shape of the hypopharynx, the shape of the pronotum, the setation of the mandibles, and the relative size of the femora. In order to confirm these differences, we examined the type series of <i>A. edmundsi</i> and found that all of the differences indicated by the Wang and McCafferty (1995) figures are the result of inaccurate illustrations or poor specimens. Their figure of the hypopharynx does accurately represent the specimen from which it was drawn, but the specimen was killed in the process of moulting and the hypopharynx is distorted; we have also observed this distortion in mature larvae within large series of specimens that all have the typical posteriorly directed, sharply pointed lobes of the superlingua, so is it not likely a specific, but rather an artifact of moulting. In all examined characters, the paratype nymphs of <i>A. edmundsi</i> appear to be identical to those of <i>A. tarsalis</i>. Neither the association of the nymphs and adults of either <i>A. edmundsi</i> nor <i>A. tarsalis</i> was confirmed through rearing. We believe, however, that the nymph of <i>A. tarsalis</i> described herein is correctly associated with the adult as it was collected at essentially the same location as an adult male, whereas the nymphs and holotype male of <i>A. edmundsi</i> were collected from different locations. It is likely that the association made by Wang and McCafferty (1995) is incorrect and they inadvertently described the nymph of <i>A. tarsalis</i>.</p> <p> The adult male of <i>A. edmundsi</i> appears to be a good species, and differs from males of <i>A. tarsalis</i> in having the first segment of the hind tarsus shorter than the hind tibia. Additionally, the fore wing is approximately 3.5 times longer than wide, whereas in <i>A. tarsalis</i> the fore wing is less than 3 times longer than wide (Fig. 12). The narrow hind wing described and illustrated by Wang and McCafferty (1995) is inaccurately drawn; the wing from which the drawing was made is folded, making it appear narrower than it actually is. The other hind wing of the holotype is not folded and has the same shape as those of <i>A. tarsalis</i>. The female subimago described by Wang and McCafferty (1995) as <i>A. edmundsi</i> has fore wings that are 2.8 times longer than wide, so is unlikely to actually be <i>A. edmundsi</i>. It is probable that this specimen is <i>A. tarsalis</i>, but because the female of <i>A. tarsalis</i> is unknown, we cannot confirm this. Until <i>A. edmundsi</i> becomes better known, the species concept should be restricted to that of the holotype.</p> <p> <b>Distribution and ecology.</b> <i>Atopopus tarsalis</i> is endemic to Borneo and is herein reported for the first time from Indonesia (East Kalimantan) although its presence was expected, based on its occurrence in Malaysia (Sabah).</p> <p> Nymphs of this species have been found in small to medium size streams as well as in rivers in lowland dipterocarp forests. The watercourses ranged from 0.5–15 m wide, 2–80 cm deep, had current speeds between 0.2–1.4 m /s and water temperatures between 23.8–26.5°C. Despite this wide range of habitats, <i>A. tarsalis</i> has been shown to be a sensitive species, mainly present in pristine habitats (reference sites “group green” according to Derleth 2003).</p> <p> A striking characteristic of this species is that 94% of all specimens were collected during qualitative prospecting whereas only 6% were collected with a Surber net. Detailed field observations show that <i>A. tarsalis</i> microhabitats are not located in small to medium size substrata where quantitative samples have been performed, but rather on and around large rocks and boulders (see below).</p> <p> No adults of <i>A. tarsalis</i> were collected in light traps at either dusk or at dawn. The single male imago was caught resting under a leaf in the forest around noon. Nuptial flight probably occurs during the afternoon.</p> <p> <b>Behaviour.</b> Nymphs of <i>A. tarsalis</i> have been mainly found scraping periphyton on large boulders. They generally are located a few centimetres below the water surface and, when disturbed, they move like crabs around the stone and are difficult to catch. What seems unique, to our knowledge, is that <i>A. tarsalis</i> nymphs, when not disturbed, are frequently found on rocks above the water surface. They can be found up to 20 centimetres above the water surface and in some occasions they were found at the top of the rock. As soon as they are approached too closely, they return to the water.</p> <p> As far as we know, this behaviour has never been reported for any mayfly nymph. A South American mayfly, <i>Cloeodes hydation</i> McCafferty & Lugo-Ortiz, 1995, a rock pool colonizer, has been reported to resist up to 9 hours out of the water (Nolte <i>et al.</i> 1996). It seems to be an extreme adaptation to frequent drought in this peculiar habitat, and seems to be a passive behaviour. <i>A. tarsalis</i> behaviour is quite different since this species actively leaves the water and returns to it periodically, obviously to avoid dehydration. Our preliminary field observations, based on modest research facilities, indicate that <i>A. tarsalis</i> nymphs can spend up to 20 minutes out of the water, even in open streams and rivers with direct sunlight.</p> <p> We have then to conclude that nymphs of <i>A. tarsalis</i> are able to retain a film of water around them to avoid complete dehydration. In that sense, the special shape of the head, with a thickened cephalic capsule, as well as the reinforcement of the gills may play a role in maintaining this water film and/or avoiding a total dehydration.</p> <p> Reasons for this peculiar behaviour are not clear. Two hypotheses can be put forward. The first is that this behaviour allows <i>A. tarsalis</i> nymphs to avoid fish predation. The general behaviour of macroinvertebrates in the presence of carnivorous fishes is drifting (see e.g. Huhta <i>et al.</i> 1999; Huhta <i>et al.</i> 2000; McIntosh <i>et al.</i> 2002). This should be especially the case in rivers where fish composition is more diversified than in small streams (but see Melo & Froehlich 2004 for contrasting results). Climbing out of the water may be a less risky behaviour than drifting for avoiding predation for <i>A. tarsalis</i>.</p> <p> Another hypothesis is that this behaviour may prevent <i>A. tarsalis</i> nymphs from being dislodged by the frequent and sudden spates that occur in the study area (pers. obs). When it is raining, the water level in streams and rivers increases rapidly, as do discharge and turbidity, inducing drift among macroinvertebrates and mayflies in peculiar (see e.g. Brittain & Eikeland 1988; Lancaster 1992).</p> <p>But it is also possible that both hypotheses may be involved in this behaviour, as suggested by Dudgeon (1993). This will require complementary field studies in the future.</p> <p> Finally it is worth mentioning that <i>A. tarsalis</i> is not the only mayfly that exhibits this behaviour. The baetid nymph <i>Platybaetis probus</i> Müller-Liebenau has been found generally together with <i>A. tarsalis</i> and is also frequently found above the water level. The morphological adaptation of this species will be discussed elsewhere.</p>Published as part of <i>Sartori, Michel & Derleth, Pascale, 2007, The nymph of Atopopus tarsalis Eaton, 1881 (Ephemeroptera, Heptageniidae): first description, ecology and behaviour, pp. 25-32 in Zootaxa 1586</i> on pages 25-31, DOI: <a href="http://zenodo.org/record/178454">10.5281/zenodo.178454</a>
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
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