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Limia mandibularis, a new livebearing fish (Cyprinodontiformes: Poeciliidae) from Lake Miragoane, Haiti
Get PDFRodriguez-Silva, Rodet, Torres-Pineda, Patricia, Josaphat, James (2020): Limia mandibularis, a new livebearing fish (Cyprinodontiformes: Poeciliidae) from Lake Miragoane, Haiti. Zootaxa 4768 (3): 395-404, DOI: 10.11646/zootaxa.4768.3.
FIGURE 3 in Limia mandibularis, a new livebearing fish (Cyprinodontiformes: Poeciliidae) from Lake Miragoane, Haiti
No full textFIGURE 3. Mouth of a cleared specimen of Limia mandibularis sp. nov. (OMNH 86831, female, 41.5 mm SL) showing the peculiar arrangement of bones of the upper and lower jaws. Premax: premaxillar, max: maxilla, dent: dentary, ang: anguloarticular, qu: quadratePublished as part of Rodriguez-Silva, Rodet, Torres-Pineda, Patricia & Josaphat, James, 2020, Limia mandibularis, a new livebearing fish (Cyprinodontiformes: Poeciliidae) from Lake Miragoane, Haiti, pp. 395-404 in Zootaxa 4768 (3) on page 398, DOI: 10.11646/zootaxa.4768.3.6, http://zenodo.org/record/378408
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
Limia mandibularis Rodriguez-Silva & Torres-Pineda & Josaphat 2020, sp. nov.
No full textLimia mandibularis, sp. nov. (Figs. 2-6, Tables 1 and 2) Holotype. OMNH 86828, adult male 35.5 mm SL (Fig. 2), Lake Miragoane, Haiti; coordinates 18°25’33.2” N, 73°02’56.9”W; R. Rodriguez-Silva, P. Torres-Pineda, J. Josaphat, and P. Michard Beaujour, June 5, 2019 Paratypes. Same origin, date and collectors as holotype. OMNH 86829, 1 female, 41.0 mm SL (Fig. 2); OMNH 86831, 1 male, 38.5 mm SL and 1 female, 41.5 mm SL (cleared and stained specimens); OMNH 86832, lot of 5 females, 36.0- 41.5 mm SL; MNHNSD.22.10426, 1 female, 39.5 mm SL; MNHNSD.22.10427, 1 female, 33.0 mm SL: MNHNSD.22.10428, 1 female, 33.0 mm SL. Diagnosis. Limia mandibularis sp. nov. is uniquely diagnosed by the presence of a well-developed lower jaw due to the presence of an elongate anguloarticular bone (Fig. 3). The new species can also be identified by the lack of preorbital and preopercular pores and by the presence of single preorbital and preopercular canals forming open grooves (Fig. 4). Limia mandibularis sp. nov. can be further distinguished by the combination of the following characters: dorsal fin with 8 rays and its origin is slightly behind of the origin of the anal fin in females; 13 predorsal scales; caudal fin symmetrical and truncate or slightly convex; no crossbars, spots or blotches on body in both sexes. See additional comments in the Discussion below. Description. Elongate body with deep caudal peduncle. Post-anal region moderately compressed towards caudal peduncle. Dorsal profile slightly concave from snout tip to posterior edge of eye; convex from middle of eye to origin of dorsal fin; slightly concave or straight from dorsal fin origin to caudal fin. Ventral profile convex with distinctive protuberance in the lower jaw area that is formed by the joint of anguloarticular and quadrate bones (quadrato-mandibular joint). Post-anal profile slightly concave or straight (Fig. 2). Gonopodial segments of ray 4p serrae 11 (Fig. 5). Predorsal scales 12 to 13 (usually 13) and lateral scales 26 to 28 (usually 26). Dorsal fin with 8 rays (Table 1). Caudal fin with 15 to 17 rays (usually 16), truncate or slightly convex, and symmetrical in both sexes. Mouth wide and superiorly oriented. Teeth of outer row conical in upper and lower jaws. Vertebral column with 30 vertebrae. Color of preserved specimens. Dorsal and middle portion of body dark, with noticeable reticulated pattern due to black pigmentation on edges of scales. Ventral region of body and scales of the hypural area with tannish coloration, much darker below pectoral fins. All fins hyaline (Fig. 2). Color in live specimens. Yellowish background towards dorsal region of body, darker in snout and above opercula. Ventral region with silver coloration. No distinctive features like spots, bars or blotches on body or fins in both sexes (Fig. 6). Distribution and ecological notes. Limia mandibularis sp. nov. is only known from the north bight of Lake Miragoane in Haiti. The lake seems very isolated in terms of connectivity with other water bodies as we did not see any tributary river or stream, but only mountain springs that lead to the lake. Our observations agree with the classification of Curtis & Hodell (1993) of the lake as an endorheic drainage. The species herein described was collected in a clear water path with slow current exiting the lake. Water temperature was 29.9 °C and water conductivity was 321 microS/cm on the collecting date (June 5 th, 2019). The area is characterized by the presence of muddy bottoms and some semi-submerged and submerged vegetation growing near the banks (Fig. 7). Limia mandibularis was sympatric with Gambusia beebei, five other Limia species (L. miragoanensis, L. immaculata, L. nigrofasciata , L. garnieri and L. islai), Nandopsis haitiensis and two species of African cichlids introduced in the lake (Oreochromis aureus and Tilapia sp.). Etymology. The specific epithet mandibularis, from the Latin mandibula (jaw), is in reference to the well-developed lower jaw, a character that distinguishes the species. The vernacular name “Jawed Limia ” is proposed for this species, due to the distinct protuberance that can be seen in the lower jaw.Published as part of Rodriguez-Silva, Rodet, Torres-Pineda, Patricia & Josaphat, James, 2020, Limia mandibularis, a new livebearing fish (Cyprinodontiformes: Poeciliidae) from Lake Miragoane, Haiti, pp. 395-404 in Zootaxa 4768 (3) on pages 397-401, DOI: 10.11646/zootaxa.4768.3.6, http://zenodo.org/record/378408
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
Ecological drivers of species radiations in the genus Limia (Teleostei, Poeciliidae) in the West Indies
Get PDFThe archipelagoes of the West Indies in the Caribbean represent geographically composite regions that provide ideal settings to study the evolution of a very distinctive biota. The combination of complex geological events and tropical climatic conditions has driven radiation processes that are not homogeneous for all groups in the Caribbean. In the course of my dissertation work, I examined the case of livebearing fishes of the genus Limia (Teleostei: Poeciliidae) that show some deviations from the positive species‐area relationship predicted by the theory of island biogeography. I particularly analyzed the potential role of some ecological drivers in explaining the lopsided distribution of Limia fishes in the Greater Antilles. Chapter one is an extensive review about the West Indian biogeography that highlights divergent diversification patterns observed in terrestrial versus aquatic groups. This review also sheds light on the unbalanced number of studies covering the biogeography of these groups of organisms in the West Indies. Chapter two is an assessment of the variation of tolerance to extreme temperatures (measured as critical thermal minimum (CTmin) and maximum (CTmax)) and also the thermal breadth for multiple species of Limia occurring in the West Indies and that occupy different altitudinal distributions. This study analyzes the role of temperature gradients across elevations in determining species distribution in the genus. Chapter three evaluates the diet and feeding specializations of Limia through a comparative analysis based on data of the gut content of eight species. This chapter explores the potential role of the feeding ecology in the radiation of the genus Limia in the Caribbean. Finally, chapter four uses laboratory experiments and also fieldwork data to test whether sexual selection or natural selection may explain the presence of color polymorphism in Limia vittata, an endemic species to Cuba.
Overall, my results show that species richness in the genus Limia is positively correlated with island size but also with the presence of elevations showing that not only island area but also mountainous relief may be an important factor determining the number of freshwater species in the Greater Antilles. In addition, we found no association between thermal tolerance and the altitudinal distribution in Limia species, suggesting that biotic factors such as species interactions, diet specializations, and others should be taken into account when interpreting current distribution patterns. Even though our study showed that the majority of Limia species tend to be feeding generalists, some degree of diet specialization occurs in certain species from Hispaniola where the diversity of the genus Limia is remarkably higher compared to the rest of the Greater Antilles. Lastly, we revealed that natural selection determined by habitat variation in terms of salinity levels, is the most important factor in maintaining color polymorphism in L. vittata. Salinity levels could be indirectly responsible for maintaining different color morphs in this species, likely due to the regulatory effect of saline gradients on predation regimes
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
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