Freezing susceptibility and freezing tolerance in Palaearctic Cetoniidae (Coleoptera)

2001 ◽  
Vol 79 (1) ◽  
pp. 67-74 ◽  
Author(s):  
P Vernon ◽  
G Vannier
Keyword(s):  
Freezing Tolerance ◽  
Cold Hardiness ◽  
Taxonomic Revision ◽  
Taxonomic Position ◽  
Freezing Resistance ◽  
Seasonal Freezing ◽  
Hollow Trees ◽  
Adaptive Mechanisms ◽  
The Family ◽  
Cetonia Aurata

Insects have evolved various adaptations that allow them to survive adverse seasons. In terms of cold-hardiness, they may classically be divided into freezing-susceptible versus freezing-tolerant species. But this concept of two alternative cold-hardiness strategies is now amendable, and to better understand these adaptive mechanisms, it is of interest to study freezing resistance in taxonomically related insect species, i.e., belonging to the same family or to a group of closely related organisms sharing similar resources. Freezing susceptibility and freezing tolerance have previously been recorded in the larvae of species in the same guild of the family Cetoniidae, which mainly colonise wood mould in hollow trees. We compared freezing hardiness in five species of Cetoniidae, three species in the subfamily Trichiinae, Gnorimus nobilis (Linné), Trichius fasciatus (Linné), and Osmoderma eremita (Scopoli), and two species in the subfamily Cetoniinae, Cetonia aurata (Linné) and Cetonischema aeruginosa (Drury). Our results mainly show that two contrasting mechanisms are used during winter by third-instar larvae: those of the Trichiinae (apart from O. eremita) are probably characterized by year-round freezing susceptibility, and those of O. eremita and the Cetoniinae are probably distinguished by seasonal freezing susceptibility (summer) and seasonal freezing tolerance (winter). We question the current taxonomic position of the genus Osmoderma. Morphological, ecological, and behavioural arguments may be put forward to support the transfer of O. eremita from the Trichiinae to the Cetoniinae, and we stress that ecophysiological arguments, often neglected in this kind of taxonomic revision, must also be taken into account.

A taxonomic revision of the genus Habrobathynella Schminke, 1973, with the description of four new species from southeastern India (Crustacea, Malacostraca, Bathynellacea)

Zootaxa ◽  
2010 ◽  
Vol 2532 (1) ◽  
pp. 1 ◽  
Author(s):  
YENUMULA RANGA REDDY ◽  
VENKATESWARA RAO TOTAKURA
Keyword(s):  
New Species ◽  
Andhra Pradesh ◽  
Taxonomic Revision ◽  
Taxonomic Position ◽  
Indian Species ◽  
Generic Diagnosis ◽  
Special Importance ◽  
Line Drawings ◽  
The Family ◽  
High Diversity

The genus Habrobathynella Schminke, 1973, presently contains six species. Four new species of the genus Habrobathynella, viz. H. krishna n. sp., H. vaitarini n. sp., H. savitri n. sp. and H. vidua n. sp. are described and illustrated herein and their taxonomic position in the genus Habrobathynella discussed. Inhabiting certain rivers and borewells in the State of Andhra Pradesh, southeastern India, these new species introduce several morphologic features that are unique to either the genus or the family Parabathynellidae. The spine row on the uropodal sympod now displays five character states, and high diversity is also seen in the male thoracopod VIII. The salient morphologic characters and their various states in all the habrobathynellid species are reviewed and the original generic diagnosis revised. The palpless mandible with somewhat pyriform pars molaris, bearing 5–6 teeth, is recognised as a signal synapomorphy of Habrobathynella. Two more synapomorphies based on the male thoracopod VIII and caudal furca are added. Considering its special importance in taxonomy, the male thoracopod VIII of the four already known Indian species, viz. H. nagarjunai Ranga Reddy, 2002; H. schminkei Ranga Reddy, 2004; H. indicaRanga Reddy & Schminke, 2005 and H. plenituda Ranga Reddy & Schminke, 2009, has been reexamined based on topotypes and freshly illustrated with line drawings and digital images, and errors in the original accounts are corrected. Also, the ecology, biogeography and conservation of Habrobathynella species are briefly discussed.

Comments on “Is Copytus Skogsberg, 1939 (Crustacea: Ostracoda) a neocytherideid? With description of a new family and two new species” by Coimbra, Bergue & Ramos (2020)

Zootaxa ◽  
2021 ◽  
Vol 4950 (2) ◽  
pp. 398-400
Author(s):  
OKAN KÜLKÖYLÜOĞLU
Keyword(s):  
New Species ◽  
Integrated Approach ◽  
Taxonomic Position ◽  
New Family ◽  
As Species ◽  
Diagnostic Characteristics ◽  
The Family ◽  
Two New Species

Most recently, Coimbra et al. (2020) published an article in this journal (Zootaxa, 4729 (2): 177–194) questioning the taxonomic position of the genus Copytus Skogsberg, 1939 (Crustacea, Ostracoda) along with proposing it as the type genus of their new family (Copytidae Coimbra et al., 2020), and erecting two new species that were listed by previous authors as Copytus sp. 1 and Copytus sp. 2. The main diagnostic characteristics of their new proposed family (and the genus Copytus) are the hinge type and muscle scars on the carapace and/or valves (see lines 6–8 from the bottom, p. 179 in Coimbra et al. 2020). They also underlined that (p. 179) “...this study is based exclusively on the morphology of the animals’ hard parts”. While the authors considered another genus (Neocopytus) proposed by Külköylüoğlu, Colin & Kılıç (2007) of the family Neocytherididae as invalid, they interestingly transferred some species of Neocopytus to Copytus as species of their new family (Coimbra et al. 2020). Herein, my point with the comments listed below is to clarify that, when possible, both soft and hard parts should be considered in taxonomy, and such an integrated approach clearly indicates that Neocopytus is a valid and taxonomically useful genus. 

scholarly journals Phylogenetic relationships among the clownfish-hosting sea anemones

2019 ◽  
Author(s):  
Benjamin M. Titus ◽  
Charlotte Benedict ◽  
Robert Laroche ◽  
Luciana C. Gusmão ◽  
Vanessa Van Deusen ◽  
...  
Keyword(s):  
Phylogenetic Reconstruction ◽  
Taxonomic Revision ◽  
Sea Anemone ◽  
Coral Triangle ◽  
Sea Anemones ◽  
Ecological Processes ◽  
Holistic Understanding ◽  
The Family ◽  
Genus 2 ◽  
Insight Into

AbstractThe clownfish-sea anemone symbiosis has been a model system for understanding fundamental evolutionary and ecological processes. However, our evolutionary understanding of this symbiosis comes entirely from studies of clownfishes. A holistic understanding of a model mutualism requires systematic, biogeographic, and phylogenetic insight into both partners. Here, we conduct the largest phylogenetic analysis of sea anemones (Order Actiniaria) to date, with a focus on expanding the biogeographic and taxonomic sampling of the 10 nominal clownfish-hosting species. Using a combination of mtDNA and nuDNA loci we test 1) the monophyly of each clownfish-hosting family and genus, 2) the current anemone taxonomy that suggests symbioses with clownfishes evolved multiple times within Actiniaria, and 3) whether, like the clownfishes, there is evidence that host anemones have a Coral Triangle biogeographic origin. Our phylogenetic reconstruction demonstrates widespread poly-and para-phyly at the family and genus level, particularly within the family Stichodactylidae and genus Sticodactyla, and suggests that symbioses with clownfishes evolved minimally three times within sea anemones. We further recover evidence for a Tethyan biogeographic origin for some clades. Our data provide the first evidence that clownfish and some sea anemone hosts have different biogeographic origins, and that there may be cryptic species of host anemones. Finally, our findings reflect the need for a major taxonomic revision of the clownfish-hosting sea anemones.

scholarly journals A taxonomic revision of the family Harrimaniidae (Hemichordata: Enteropneusta) with descriptions of seven species from the Eastern Pacific

Zootaxa ◽  
2010 ◽  
Vol 2408 (1) ◽  
pp. 1 ◽  
Author(s):  
C. DELAND ◽  
C. B. CAMERON ◽  
K. P. RAO ◽  
W. E. RITTER ◽  
T. H. BULLOCK
Keyword(s):  
New Species ◽  
Taxonomic Revision ◽  
Morphological Characters ◽  
Eastern Pacific ◽  
Nomen Nudum ◽  
Phylogenetic Hypothesis ◽  
Number Of Species ◽  
Dichotomous Key ◽  
The Family ◽  
The Status

The family Harrimaniidae (Hemichordata: Enteropneusta) is revised on the basis of morphological characters. The number of harrimaniid genera is increased to nine by the addition of Horstia n. gen., Mesoglossus n. gen., Ritteria n. gen. and Saxipendium, a genus previously assigned to the monospecific family Saxipendiidae. The number of species is increased to 34, resulting from the description of five new species from the eastern Pacific — Horstia kincaidi, Mesoglossus intermedius, M. macginitiei, Protoglossus mackiei and Ritteria ambigua. A description is supplied for a sixth harrimaniid species, Stereobalanus willeyi Ritter & Davis, 1904, which previously had the status of a nomen nudum. Four harrimaniids previously assigned to the genus Saccoglossus are transfered to the genus Mesoglossus — M. bournei, M. caraibicus, M. gurneyi and M. pygmaeus, while Saccoglossus borealis is reassigned to the genus Harrimania. Notes on habitat and zoogeography are included for the seven foregoing species and a table of diagnostic characters for existing and new species and a dichotomous key to the enteropneust families and harrimaniid genera are provided. Finally, a phylogenetic hypothesis concerning the Harrimaniidae is postulated, with discussion on the evolution of the group.

Fructan in winter wheat, triticale, and fall rye cultivars of varying cold hardiness

1988 ◽  
Vol 66 (9) ◽  
pp. 1723-1728 ◽  
Author(s):  
Michio Suzuki ◽  
H. G. Nass
Keyword(s):  
Winter Wheat ◽  
Cold Hardiness ◽  
Wheat Cultivar ◽  
Degree Of Polymerization ◽  
Lethal Temperature ◽  
Winter Wheat Cultivar ◽  
Freezing Resistance ◽  
Winter Cereals ◽  
Opposite Trend ◽  
High Concentrations

Eight winter wheat, one triticale, and three fall rye cultivars with mean lethal temperature (LT50) values from −5.5 to −20.0 °C were harvested in late November and analyzed for fructans. Fructose, sucrose, and oligofructans with a degree of polymerization (DP) of 6 or lower were found in all cultivars. The concentration of DP 4 fructan was higher than that of DP 5 in winter wheat and triticale, while the opposite trend was found in fall rye. Fructans with a DP of 7 or higher (high DP fructans) were found at high concentrations in hardy winter wheat and fall rye. The high DP fructan was very low or negligible in the least hardy winter wheat cultivar 'Super X'. Fructans in winter cereals consisted mainly of inulin type with a β-2-1 linkage. The activity of phlein sucrase, which catalyzes synthesis of phlein, was much lower in winter cereals compared with phlein-rich grasses. It was concluded that high DP fructans of inulin type in basal top tissues of winter cereals were more closely associated with freezing resistance than low DP fructans.

A NEW ANOETID (ACARI) OF THE GENUS CREUTZERIA FROM THE SEYCHELLES

1979 ◽  
Vol 111 (11) ◽  
pp. 1201-1205 ◽  
Author(s):  
H.H.J. Nesbitt
Keyword(s):  
New Species ◽  
Taxonomic Position ◽  
Pitcher Plant ◽  
The Family ◽  
A New Species

AbstractThe taxonomic position of the genus Creutzeria in the family Anoetidae is examined, and a description of a new species, C. seychellensis, from the pitcher plant, Nepenthes pervillei, from the Seychelles is given. A couplet is proposed for the Hughes-Jackson key that would separate the genera Creutzeria and Zwickia.

The genus Wellstedia (Boraginaceae: Wellstedioideae) in southern Africa

Bothalia ◽  
2008 ◽  
Vol 38 (1) ◽  
pp. 57-63 ◽  
Author(s):  
E. Retief ◽  
A. E. Van Wyk
Keyword(s):  
Southern Africa ◽  
Arid Regions ◽  
Taxonomic Revision ◽  
Dwarf Shrub ◽  
Disjunct Distribution ◽  
Distribution Map ◽  
Strong Similarity ◽  
The Family ◽  
Northern Cape ◽  
The Arid Regions

This regional taxonomic revision of the genus  Wellstedia  Balf.f., a member of the family Boraginaceae  s.I. (including Hydrophyllaceae s.str.), is part of a series of publications on the Boraginaceae in southern Africa.  Wellstedia comprises six species, five in Socotra, Somalia and Ethiopia with the remaining one.  W. dinteri Pilg.. occurring in southern Africa.  W dinteri Pilg. subsp. dinteri occurs in Namibia and the Northern Cape, whereas the newly instated subspecies W. dinteri subsp. gracilior (D.R.Hunt) Retief A.E.van Wyk, based on W. dinteri Pilg. var. gracilior D.R.Hunt, is confined to Namibia only. The disjunct distribution of Wellstedia and numerous other plant and animal taxa between the arid regions of northeastern Africa and southern Africa is usually explained by the postulated periodic existence of an arid corridor between the two regions during the arid phases of the Pleistocene and even earlier.  Wellstedia is treated here in Wellstedioideae, a subfamily of Boraginaceae s.I. but is sometimes placed in a family of its own, Wellstediaceae Pilger. Morphologically Wellstedia displays strong similarity to genera of the Ehretioideae and also to certain members of the Hydrophyllaceae. The genus is characterized by a perennial, dwarf shrub habit, densely hairy leaves. 4-merous flowers, a terminal, bifid style and a 1- or 2-seeded capsule. A key to the two subspecies, diagnostic characters, a distribution map and illustrations of various macro- and micromorphological features are provided.

Taxonomic revision of the genus Gephyrellula Strand, 1932 (Arachnida, Araneae, Philodromidae)

Zootaxa ◽  
2018 ◽  
Vol 4527 (3) ◽  
pp. 381 ◽  
Author(s):  
FABRICIO H. SANTOS ◽  
CRISTINA A. RHEIMS
Keyword(s):  
Geographical Distribution ◽  
Type Species ◽  
Taxonomic Revision ◽  
Junior Synonym ◽  
Distribution Map ◽  
Free Living ◽  
The Family ◽  
Family Level

Spiders of the family Philodromidae are free-living active predators, with laterigrade legs, eyes without tubercles, two tarsal claws and claw tufts. Although very common in zoological collections, their systematics is poorly known, especially in the Neotropics, and their specimens are usually identified only at family level. In this paper, the genus Gephyrellula Strand, 1932 is revised and the type species, G. violacea (Mello-Leitão, 1918) is redescribed and illustrated. Gephyrellula paulistana (Soares, 1943) is considered a junior synonym of G. violacea and thus, the genus becomes monotypic. In addition, the geographical distribution is extended and an updated distribution map is provided. 

Mechanism of freezing resistance in eco-dormant birch buds under winter subzero temperatures

2019 ◽  
Author(s):  
Keita Endoh ◽  
Seizo Fujikawa
Keyword(s):  
Cold Hardiness ◽  
Common Property ◽  
Leaf Primordia ◽  
Intercellular Spaces ◽  
Freezing Resistance ◽  
Cooling Rates ◽  
Dormant State ◽  
Sem Observation ◽  
Subzero Temperatures ◽  
The Common

Abstract Maximum freezing resistance is a component of winter survival and is associated with the eco-dormant state. Differential thermal analysis (DTA) has shown that changes of the freezing response of the dormant buds depend not only on species and bud type, but also on cooling rates. In order to clarify the freezing adaptation at the cellular level of eco-dormant buds in Japanese white birch, birch buds cooled at a rate of 0.2 °C min−1 and 5 °C day−1 were precisely examined by cryo-scanning electron microscopy (cryo-SEM). Freezing responses of floral dormant buds having female inflorescent primordia and leaf primordia with high-cold hardiness were assessed for extracellular freezing patterns by DTA. Cryo-SEM observation showed freezing of viscous solution filling intercellular spaces within buds and formation of extracellular ice in a random distribution within certain tissues, including green scales, leaf primordia and peduncles. The tissues producing extracellular ice had the common property that distinct intercellular spaces were present among cells having comparatively thick primary walls. In contrast, extracellular ice was not formed within flower primordium and parts of leaf primordium. These tissues had also the common property that no detectable intercellular spaces existed around the cells having thin primary walls. Cryo-SEM observation confirmed that all cells in tissues, regardless of whether extracellular ice was formed within tissues, and also regardless of differences in cooling rates, showed distinct cellular shrinkage by freezing. Recrystallization experiments by cryo-SEM confirmed that all freezable water in cells was eliminated by cooling at 0.2 °C min−1 at least to −30 °C. These results confirmed that all cells in birch buds responded to subzero temperatures through rapid equilibrium dehydration. In contrast to deep supercooling associated with extraorgan freezing of other freezing resistant buds of trees in an eco-dormant state, the mechanism of freezing resistance in eco-dormant birch buds is freezing adaptations by extracellular freezing.

scholarly journals Phylogeny and morphology of genus Nephrocytium (Sphaeropleales, Chlorophyceae, Chlorophyta) from China

Phytotaxa ◽  
2017 ◽  
Vol 319 (1) ◽  
pp. 84 ◽  
Author(s):  
XUDONG LIU ◽  
HUAN ZHU ◽  
BENWEN LIU ◽  
GUOXIANG LIU ◽  
ZHENGYU HU
Keyword(s):  
Phylogenetic Analyses ◽  
Light And Electron Microscopy ◽  
Taxonomic Position ◽  
Phylogenetic Position ◽  
Phytoplankton Communities ◽  
Close Phylogenetic Relationship ◽  
The Family ◽  
Close Relationship ◽  
Molecular Phylogenetic

The genus Nephrocytium Nägeli is a common member of phytoplankton communities that has a distinctive morphology. Its taxonomic position is traditionally considered to be within the family Oocystaceae (Trebouxiophyceae). However, research on its ultrastructure is rare, and the phylogenetic position has not yet been determined. In this study, two strains of Nephrocytium, N. agardhianum Nägeli and N. limneticum (G.M.Smith) G.M.Smith, were identified and successfully cultured in the laboratory. Morphological inspection by light and electron microscopy and molecular phylogenetic analyses were performed to explore the taxonomic position. Ultrastructure implied a likely irregular network of dense and fine ribs on the surface of the daughter cell wall that resembled that of the genus Chromochloris Kol & Chodat (Chromochloridaceae). Phylogenetic analyses revealed that Nephrocytium formed an independent lineage in the order Sphaeropleales (Chlorophyceae) with high support values and a close phylogenetic relationship with Chromochloris. Based on combined morphological, ultrastructural and phylogenetic data, we propose a re-classification of Nephrocytium into Sphaeropleales, sharing a close relationship with Chromochloris.

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