SciCombinator

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Concept: Genus

328

Stretching elastic tissues and using their recoil to power movement allows organisms to release energy more rapidly than by muscle contraction directly, thus amplifying power output. Chameleons employ such a mechanism to ballistically project their tongue up to two body lengths, achieving power outputs nearly three times greater than those possible via muscle contraction. Additionally, small organisms tend to be capable of greater performance than larger species performing similar movements. To test the hypothesis that small chameleon species outperform larger species during ballistic tongue projection, performance was examined during feeding among 20 chameleon species in nine genera. This revealed that small species project their tongues proportionately further than large species, achieving projection distances of 2.5 body lengths. Furthermore, feedings with peak accelerations of 2,590 m s(-2), or 264 g, and peak power output values of 14,040 W kg(-1) are reported. These values represent the highest accelerations and power outputs reported for any amniote movement, highlighting the previously underestimated performance capability of the family. These findings show that examining movements in smaller animals may expose movements harbouring cryptic power amplification mechanisms and illustrate how varying metabolic demands may help drive morphological evolution.

Concepts: Evolution, Metabolism, Biology, Organism, Species, Genus, Tongue, Chameleon

198

Taxonomists have been tasked with cataloguing and quantifying the Earth’s biodiversity. Their progress is measured in code-compliant species descriptions that include text, images, type material and molecular sequences. It is from this material that other researchers are to identify individuals of the same species in future observations. It has been estimated that 13% to 22% (depending on taxonomic group) of described species have only ever been observed once. Species that have only been observed at the time and place of their original description are referred to as oncers. Oncers are important to our current understanding of biodiversity. They may be validly described species that are members of a rare biosphere, or they may indicate endemism, or that these species are limited to very constrained niches. Alternatively, they may reflect that taxonomic practices are too poor to allow the organism to be re-identified or that the descriptions are unknown to other researchers. If the latter are true, our current tally of species will not be an accurate indication of what we know. In order to investigate this phenomenon and its potential causes, we examined the microbial eukaryote genus Gymnodinium. This genus contains 268 extant species, 103 (38%) of which have not been observed since their original description. We report traits of the original descriptions and interpret them in respect to the status of the species. We conclude that the majority of oncers were poorly described and their identity is ambiguous. As a result, we argue that the genus Gymnodinium contains only 234 identifiable species. Species that have been observed multiple times tend to have longer descriptions, written in English. The styles of individual authors have a major effect, with a few authors describing a disproportionate number of oncers. The information about the taxonomy of Gymnodinium that is available via the internet is incomplete, and reliance on it will not give access to all necessary knowledge. Six new names are presented - Gymnodinium campbelli for the homonymous name Gymnodinium translucens Campbell 1973, Gymnodinium antarcticum for the homonymous name Gymnodinium frigidum Balech 1965, Gymnodinium manchuriensis for the homonymous name Gymnodinium autumnale Skvortzov 1968, Gymnodinium christenum for the homonymous name Gymnodinium irregulare Christen 1959, Gymnodinium conkufferi for the homonymous name Gymnodinium irregulare Conrad & Kufferath 1954 and Gymnodinium chinensis for the homonymous name Gymnodinium frigidum Skvortzov 1968.

Concepts: Biodiversity, Organism, Species, Taxonomy, Genus, Microorganism, International Code of Zoological Nomenclature, Nomenclature

168

We have recently discovered a variety of unrelated phototrophic microorganisms (two microalgae and one cyanobacteria) in specialized terrestrial habitats at The Coastal Range of the Atacama Desert. Interestingly, morphological and molecular evidence suggest that these three species are all recent colonists that came from aquatic habitats. The first case is Cyanidiales inhabiting coastal caves. Cyanidiales are microalgae that are commonly found in warm acid springs, but have also been recently discovered as cave flora in Italy. The case is Dunaliella biofilms colonizing spider webs in coastal caves; Dunaliella are microalgae typically found in hypersaline habitats. The third case is Chroococcidiopsis, a genus of Cyanobacteria commonly found in deserts around the world that has also been described in warm springs. Thus, we show that the traits found in the closest ancestors of the aforementioned species (which inhabited other unrelated extreme environments) seem to be now useful for the described species in their current subaerial habitats and may likely correspond to cases of exaptations. Altogether, the Coastal Range of the Atacama Desert may be considered as a place where key steps on the colonization of land by phototrophic organisms seem to be being repeated by convergent evolution of extant microalgae and Cyanobacteria.

Concepts: Algae, Archaea, Bacteria, Evolution, Organism, Genus, Atacama Desert, Desert

51

The family Opisthoproctidae (barreleyes) constitutes one of the most peculiar looking and unknown deep-sea fish groups in terms of taxonomy and specialized adaptations. All the species in the family are united by the possession of tubular eyes, with one distinct lineage exhibiting also drastic shortening of the body. Two new species of the mesopelagic opisthoproctid mirrorbelly genus Monacoa are described based on pigmentation patterns of the “sole”-a unique vertebrate structure used in the reflection and control of bioluminescence in most short-bodied forms. Different pigmentation patterns of the soles, previously noted as intraspecific variations based on preserved specimens, are here shown species-specific and likely used for communication in addition to counter-illumination of down-welling sunlight. The genus Monacoa is resurrected from Opisthoproctus based on extensive morphological synaphomorphies pertaining to the anal fin and snout. Doubling the species diversity within sole-bearing opisthoproctids, including recognition of two genera, is unambiguously supported by mitogenomic DNA sequence data. Regular fixation with formalin and alcohol preservation is shown problematic concerning the retention of species-specific pigmentation patterns. Examination or photos of fresh material before formalin fixation is shown paramount for correct species recognition of sole-bearing opisthoproctids-a relatively unknown issue concerning species diversity in the deep-sea pelagic realm.

Concepts: Biology, Species, Fish, Genus, Ocean, Barreleye, Mirrorbelly, Opisthoproctidae

46

India’s unique and highly diverse biota combined with its unique geodynamical history has generated significant interest in the patterns and processes that have shaped the current distribution of India’s flora and fauna and their biogeographical relationships. Fifty four million year old Cambay amber from northwestern India provides the opportunity to address questions relating to endemism and biogeographic history by studying fossil insects. Within the present study seven extant and three fossil genera of biting midges are recorded from Cambay amber and five new species are described: Eohelea indica Stebner & Szadziewski n. sp., Gedanohelea gerdesorum Stebner & Szadziewski n. sp., Meunierohelea cambayana Stebner & Szadziewski n. sp., Meunierohelea borkenti Stebner & Szadziewski n. sp., and Meunierohelea orientalis Stebner & Szadziewski n. sp. Fossils of species in the genera Leptoconops Skuse, 1889, Forcipomyia Meigen, 1818, Brachypogon Kieffer, 1899, Stilobezzia Kieffer, 1911, Serromyia Meigen, 1818, and Mantohelea Szadziewski, 1988 are recorded without formal description. Furthermore, one fossil belonging to the genus Camptopterohelea Wirth & Hubert, 1960 is included in the present study. Our study reveals faunal links among Ceratopogonidae from Cambay amber and contemporaneous amber from Fushun, China, Eocene Baltic amber from Europe, as well as the modern Australasian and the Oriental regions. These findings imply that faunal exchange between Europe, Asia and India took place before the formation of Cambay amber in the early Eocene.

Concepts: Present, Nematocera, Biology, Species, Indian subcontinent, Genus, Fossil

28

Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) is a relatively new addition to the clinical microbiology laboratory. The performance of the MALDI Biotyper system (Bruker Daltonics) was compared to those of phenotypic and genotypic identification methods for 690 routine and referred clinical isolates representing 102 genera and 225 unique species. We systematically compared direct-smear and extraction methods on a taxonomically diverse collection of isolates. The optimal score thresholds for bacterial identification were determined, and an approach to address multiple divergent results above these thresholds was evaluated. Analysis of identification scores revealed optimal species- and genus-level identification thresholds of 1.9 and 1.7, with 91.9% and 97.0% of isolates correctly identified to species and genus levels, respectively. Not surprisingly, routinely encountered isolates showed higher concordance than did uncommon isolates. The extraction method yielded higher scores than the direct-smear method for 78.3% of isolates. Incorrect species were reported in the top 10 results for 19.4% of isolates, and although there was no obvious cutoff to eliminate all of these ambiguities, a 10% score differential between the top match and additional species may be useful to limit the need for additional testing to reach single-species-level identifications.

Concepts: Gene, Evolution, Mass spectrometry, Biology, Genus, Matrix-assisted laser desorption/ionization, Bruker

27

The gill lamellae ectoparasites of the spotted sea trout, Cynoscion nebulosus (Sciaenidae), in the western coast of the Yucatán Peninsula, Mexico, revealed three species of Monogenoidea: Cynoscionicola heteracantha (Manter 1938) Price, 1962 (Microcotylidae); Choricotyle cynoscioni (MacCallum, 1917) Llewellyn, 1941 (Diclidophoridae); and Diplectanum bilobatus Hargis, 1955 (Diplectanidae). Brief comments about the current taxonomic status as well as supplemental observations of all these monogenoids originally described and/or reported from the same host fish species found in the USA are provided. New illustrations, prevalence and mean intensity of infection, as well morphological and biometric data based on new specimens are shown. C. heteracantha and C. cynoscioni collected in this study represent the second and first records of the species of these genera for the Atlantic coast of Mexico. The specimens of D. bilobatus are provisionally retained within Diplectanum until an emendation of the genus and a formal revision of all named species of this monogenoidean genus are undertaken.

Concepts: Biology, Species, Atlantic Ocean, Genus, Gulf of Mexico, Sciaenidae, Cynoscion nebulosus, Cynoscion

27

In this letter, we advocate recognizing the genus Fusarium as the sole name for a group that includes virtually all Fusarium species of importance in plant pathology, mycotoxicology, medicine and basic research. This phylogenetically-guided circumscription will free scientists from any obligation to use other genus names, including teleomorphs, for species nested within this clade, and preserve the application of the name Fusarium in the way it has been used for close to a century. Due to recent changes in the International Code of Nomenclature for algae, fungi and plants (16), this is an urgent matter that requires community attention. The alternative is to break the longstanding concept of Fusarium into nine or more genera, and remove important taxa such as those in the F. solani species complex from the genus, a move we find unnecessary. Here we argue that our proposal will preserve established research connections and facilitate communication within and between research communities, and at the same time support strong scientific principles and good taxonomic practice.

Concepts: Biology, Species, Plant, Fungus, Binomial nomenclature, Genus, Kingdom, International Code of Zoological Nomenclature

25

Yuzhu (Polygonati Odorati Rhizoma), Kangdingyuzhu (Polygonati Prattii Rhizoma), and zhugenqiyuzhu (Disporopsis Fuscopictae Rhizoma) are of the same family, but of different genera. They have all often used in Chinese Materia Medica (CMM) as Polygonati Odorati Rhizoma in China market. Three species of CMM are confused. For better application, we need to identify these plants accurately. This study use pharmacognosy technique and GC-MS analysis, three species of CMM were authenticated. In macroscopic characteristics, the fruit of Polygonati Odorati Rhizoma is blue-black, while the other two are maroon and dark purple orderly. Nodes of Polygonati Odorati Rhizoma are upward and light uplift, about 1 cm spacing, while the other are not. As for microscopic characteristics, the cortex of Polygonati Odorati Rhizoma only occupies about 1/5 of the radius of the transverse section with inconspicuous endodermis, which is much smaller than others. The type of vascular bundles of Polygonati Odorati Rhizoma is closed collateral, but the other is amphivasal. Raphides of calcium oxalate are scattered, but Raphides of the other two are like brooms and neat rows. GC-MS analysis of essential oil could provide different characteristics to distinguish three species. Twenty-three compounds were identified from essential oil of Polygonati Odorati Rhizoma and the main components were n-hexadecanoic acid (49.45%), while n-hexadecanoic acid of the other two are 23.92% and 9.45%. The content of n-hexadecanoic is strongly different. This research was aimed to establish a method by pharmacognosy and GC-MS analysis to identify three CMM and for providing scientifical data to ensure accuracy of origin of three species. Microsc. Res. Tech., 2014. © 2014 Wiley Periodicals, Inc.

Concepts: Species, Plant, Purple, Genus, Calcium oxalate, Chinese herbology, Authentication, Genera

24

Plants of Cassia genus is a large tropical genus with about 600 species which were widely used as folk medicines in China and India. This genus has been known to possess various biological activity, such as antimicrobial activity, anti-inflammatory activity, antioxidant activity, antimalarial activity, antimutagenic activity, etc. The presented review summarizes the isolated and characterized flavonoids from various Cassia species and their reported biological activity. It will provide reference basis for their further research and development of the Cassia genus.

Concepts: DNA, Biology, Organism, Species, Antioxidant, Genus, Kingdom, Research and development