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Detailed morphological descriptions of the immature stages of the ant parasite Microdon mutabilis (Diptera: Syrphidae: Microdontinae) and a discussion of its functional morphology, behaviour and host specificity. Corresponding author
No full textThe myrmecophilous immature stages of hover fl ies of the genus Microdon Meigen, 1803 (Diptera, Syrphidae) are still
poorly known and only about 15 species were previously incompletely described and/or illustrated using light microscopy based on occasional fi ndings mainly of pupae and third instar larvae. The exceptional fi nding of a large number of second and third instar larvae and pupae (159 specimens) of Microdon mutabilis (Linnaeus, 1758) inside the nest of a new host species, Formica cunicularia Latreille,1798, enabled us to rear them and obtain a great number of eggs and fi rst instar larvae. We fi lmed and described the feeding behaviour and locomotion of these highly derived slug-like larvae. Combining light, fl uorescence and scanning electron (SEM) microscopy, we describe in detail and illustrate the external features of all the immature stages of M. mutabilis (eggs, larvae and pupae). Covering the entire chorion of the egg is a peculiar microsculpture composed of volcano-like processes. The three larval instars strongly differ from each other, especially at the level of the shape of the body, the posterior spiracular tubercle and the cephaloskeleton. SEM microscopy was used to describe in detail the microsculpture, sensorial structures, spiracles and cephalic appendages of larvae and pupae. Fluorescence microscopy was used to reveal the exceptional presence of resilin in the external layer of the posterior spiracular tubercle in fi rst instar larvae. The possible functional signifi cance of these structures is discussed
FIGURE 3 in Comparative morphology of myrmecophilous immature stages of European Microdon species (Diptera: Syrphidae): updated identification key and new diagnostic characters
No full textFIGURE 3. Details of first instar larvae of M. myrmicae (A, C, E, G) and M. analis (B, D, F, H): A, B—dorsal microsculpture; C, D—ventral microsculpture; E, F—dorsal flower–like sensilla; G, H—ventral flower like sensilla. A, B, C, D = 100 µm; E, F, G = 10 µm; H = 30 µm. FS, flower-like sensilla.Published as part of Scarparo, Giulia, Wolton, Robert, Molfini, Marco, Pinna, Luigi Cao & Ulio, Andrea Di Gi-, 2020, Comparative morphology of myrmecophilous immature stages of European Microdon species (Diptera: Syrphidae): updated identification key and new diagnostic characters, pp. 348-370 in Zootaxa 4789 (2) on page 355, DOI: 10.11646/zootaxa.4789.2.2, http://zenodo.org/record/399083
Foe to frenemy: predacious ant nest beetles use multiple strategies to fully integrate into ant nests
No full textAnt nest beetles (Carabidae, Paussinae, Paussini; Paussus) are renowned myrmecophiles, mostly known for their bizarre and diverse antennal shape. While little is known about their development, behavior and host range, we do know they spend most of their lives inside ant nests, feeding upon the hemolymph of ant brood and teneral workers. Recent findings suggest these beetles use a surprisingly complex strategy for interacting and deceiving ants. They have managed to break into multiple communication channels that ants use to recognize and communicate with one another in order to deceive the ants and profit from the rich resources of the nest. Mounting evidence from structural, chemical, acoustic, and behavioral studies support the hypothesis that Paussus is among the most highly integrated parasite of social insects known to date
FIGURE 2 in Comparative morphology of myrmecophilous immature stages of European Microdon species (Diptera: Syrphidae): updated identification key and new diagnostic characters
No full textFIGURE 2. First instar larvae of M. myrmicae (A, C, E) and M. analis (B, D, F): A, B—dorsal view; C, D—lateral view; E, F—ventral view. A–F = 500 µm. AO, anal opening; LLb, lateral lobe; MrB, marginal band; MG, medial groove; MrS, marginal stripe; PC, pseudocephalon; PSprTu, posterior spiracular tubercle; VLb, venteral lobe; WMrB, waves of marginal band.Published as part of Scarparo, Giulia, Wolton, Robert, Molfini, Marco, Pinna, Luigi Cao & Ulio, Andrea Di Gi-, 2020, Comparative morphology of myrmecophilous immature stages of European Microdon species (Diptera: Syrphidae): updated identification key and new diagnostic characters, pp. 348-370 in Zootaxa 4789 (2) on page 353, DOI: 10.11646/zootaxa.4789.2.2, http://zenodo.org/record/399083
Strange loves: a remarkable case of aberrant copulation in beetles (Coleoptera: Meloidae, Chrysomelidae)
No full textA case of copulation between two mimic and repellent beetle species (a male of Timarcha fracassii, and a female of Meloe autumnalis), belonging to distinct families (Chrysomelidae, Meloidae), is recorded
Microdon devius
No full textImmature stages of Microdon devius Third instar larva Figs 7–9 Body width = 7.2 ± 0.6 mm; body length = 9.4 ± 0.9 mm (n = 10). Dorsal reticulation. Dorsal reticulation extended over the whole dorsal body surface. Each process resembling a sea anemone, being divided into a smooth, columnar trunk topped by a brush composed by 20–30 long, flexible filaments (Fig. 7F). Posterior spiracular tubercle. Longer than wide, subquadrate in dorsal view, concave medially, bulged sub–basally; distance between spiracular holes 1.8 times as long as their diameter (Figs 8E, F). The base of posterior spiracular tubercle encircled by a smooth cuticular crown (Figs 8E, F). Spiracular plates flattened to slightly concave, of variable shape, separated by a broad and deep midsagittal cleft. Marginal band. Processes on the marginal band apparently without basal articulated joints (Figs 9E, F). Processes on the marginal band of three types: type one long and single, apically fringed; type two short and bifurcate, apically 2–lobed; type three composed by two type one flanking a cluster of three spiniform setae (Figs 9E, F). Puparium Figs 10, 11 Body width = 7.3 ± 0.4 mm; body length = 9.7 ± 0.5 mm (n = 10). Anterior spiracular tubercles. Length of each tubercle 2.25 times as long as wide and strongly curved (Fig. 11F), subcylindrical, slender, somewhat pointed at the apex, entirely furrowed by about 180 respiratory fissures (Figs 10E, F). Each fissure laying on a small papilla (Fig. 10F).Published as part of Scarparo, Giulia, Wolton, Robert, Molfini, Marco, Pinna, Luigi Cao & Ulio, Andrea Di Gi-, 2020, Comparative morphology of myrmecophilous immature stages of European Microdon species (Diptera: Syrphidae): updated identification key and new diagnostic characters, pp. 348-370 in Zootaxa 4789 (2) on pages 360-362, DOI: 10.11646/zootaxa.4789.2.2, http://zenodo.org/record/399083
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
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