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Zootaxa ◽  
2021 ◽  
Vol 5052 (2) ◽  
pp. 111-129
Author(s):  
PETR G. GARIBIAN ◽  
LA-ORSRI SANOAMUANG ◽  
ALEXEY A. KOTOV

It is widely accepted among the Cladocera (Crustacea) taxonomists that almost all “cosmopolitan” taxa are represented by some un-revised complexes of cryptic species. But many macro taxa of the cladocerans are still unrevised. The aim of this work is to analyze the taxonomic status of Oriental populations of the genus Bosminopsis Richard, 1895 (Anomopoda: Bosminidae) based on morphological characters. We have studied populations from India, Myanmar, Cambodia, Thailand, Laos, Vietnam, Philippines, Malaysia and Papua New Guinea and concluded that Oriental populations belong to a single species, Bosminopsis africanus (Daday, 1908), initially described from Africa. Analysis of literature data confirms that is widely distributed through whole Oriental zone. A single large mucro, or the mucro accompanied by an additional small spine in both sexes, is the main trait which differentiates B. africanus from B. zernowi Linko, 1901 distributed in more northern regions of Eurasia.  


ZooKeys ◽  
2020 ◽  
Vol 927 ◽  
pp. 37-51
Author(s):  
Katarína Krajčovičová ◽  
Aleksandr Vladimirovich Matyukhin ◽  
Jana Christophoryová

The genera Tyrannochthonius Chamberlin, 1929 and Nesocheiridium Beier, 1957 are recorded from the Tonga Islands, Polynesia, for the first time. Tyrannochthonius euasp. nov. is described from the island of Eua. Nesocheiridium onevaisp. nov. is described from the island of Onevai. This is the first discovery of a representative of the genus Nesocheiridium in more than 60 years. The holotype of the type species, Nesocheiridium stellatum Beier, 1957, is redescribed, allowing a better understanding of this poorly known genus. The genus Nesocheiridium is diagnosed by the following combination of characters: integument coarsely granulate, dorsally granulo-reticulate; vestitural setae either relatively long, with a leaf-like outline, or arcuate with a small spine; cucullus short; only 10 abdominal tergites visible in dorsal view; cheliceral rallum of four blades; venom apparatus present in both chelal fingers; fixed chelal finger with granulate swelling mesally and seven trichobothria; trichobothria ib and ist located distad of granulate swelling; eb and esb situated close together at the base of the finger; moveable chelal finger with two trichobothria.


Zootaxa ◽  
2019 ◽  
Vol 4554 (2) ◽  
pp. 386
Author(s):  
NATALIA VON ELLENRIEDER ◽  
GILLIAN W. WATSON

The adult female and male of Scaptococcus occultans sp. n. (Hemiptera: Coccomorpha: Pseudococcidae), a new mealybug species from the southwestern United States, are described and illustrated, as well as the male of S. milleri McKenzie. Females of the new species can be recognized by their unmodified prothoracic legs, anal ring with two rows of cellular pores, and presence of a circulus; the adult female is further characterized by the presence of bands across the thoracic and abdominal segments containing numerous dorsal modified oral collar tubular ducts (with the inner half of the outer duct sclerotized), quinquelocular pores and multilocular pores. The adult male of the new species differs from that of S. milleri by having unmodified prothoracic femora, small spine-like prothoracic claw denticles, fewer dorsal and ventral setae on abdominal segments II–V, and no sclerotized abdominal tergites laterally on the abdomen. The generic description of Scaptococcus is revised to include the new species, and an updated key to the adult females, diagnostic notes for the female nymphal instars, and updated distribution and host data for all the three species are provided. 


2018 ◽  
Author(s):  
Takehiro S. Tottori ◽  
Masashi Fujii ◽  
Shinya Kuroda

AbstractA dendritic spine is a small structure on the dendrites of a neuron that processes input timing information from other neurons. Tens of thousands of spines are present on a neuron. Why are spines so small and many? Because of the small number of molecules in the spine volume, biochemical reactions become stochastic. Therefore, we used the stochastic simulation model of N-methyl-D-aspartate receptor (NMDAR)-mediated Ca2+ increase to address this issue. NMDAR-mediated Ca2+ increase codes the input timing information between prespiking and postspiking. We examined how much the input timing information is encoded by Ca2+ increase against prespiking fluctuation. We found that the input timing information encoded in the spine volume (10-1 μm3) is more robust against prespiking fluctuation than that in the cell volume (103 μm3). We further examined the mechanism of the robust information transfer in the spine volume. We demonstrated that the necessary and sufficient condition for robustness is that the stochastic NMDAR-mediated Ca2+ increase (intrinsic noise) becomes much larger than the prespiking fluctuation (extrinsic noise). The condition is satisfied in the spine volume, but not in the cell volume. Moreover, we compared the information transfer in many small “spine-volume” spines with that in a single large “cell-volume” spine. We found that many small “spine-volume” spines is much more efficient for information transfer than a single large “cell-volume” spine when prespiking fluctuation is large. Thus, robustness and efficiency are two functional reasons why dendritic spines are so small and many.SignificanceA dendritic spine is a small platform for information processing in a neuron, and tens of thousands of spines are present on a neuron. Why are spines so small and many? Here we addressed this issue using stochastic simulation of NMDAR-mediated Ca2+ increase in a spine. We demonstrated that smallness of a spine enables the robust information transfer against input fluctuation, and that many small spines are much efficient for information transfer than a single large cell. This is the first demonstration that shows the advantage of the “small and many” of spines in information processing. The “small and many” strategy may be used not only in spines of a neuron, but also in other small and many intracellular organelles.


2017 ◽  
Vol 49 (4) ◽  
pp. 301-319 ◽  
Author(s):  
Arsen GASPARYAN ◽  
Harrie J. M. SIPMAN ◽  
Robert LÜCKING

AbstractRamalina europaeaGasparyan, Sipman & Lücking andR. labiosorediataGasparyan, Sipman & Lücking, two species of theR. pollinariagroup, are described here as new to science.Ramalina europaea, widely distributed in Europe, can be distinguished by small, punctiform, often terminal soralia starting out on small, spine-like branchlets, whereasR. labiosorediatafrom North America differs fromR. pollinarias. str. andR. europaeain the almost exclusively terminal soralia formed on the tips of normal lobes, originating from the underside and becoming irregularly labriform. Morphological characters, chemistry, ecology and geographical distribution are discussed and a key to the species of theRamalina pollinariagroup is provided. The topology of a maximum likelihood tree based on ITS shows the presence of three well-supported clades, corresponding to the morphological differences of the three species. The status of several historical names variously placed in synonymy with or described as infraspecific entities ofR. pollinariais reassessed and a new neotype and an epitype are designated forLichen pollinarius, a neotype forL. squarrosus, making it a synonym ofR. farinacea, and lectotypes forR. pollinariavar.elatior, making it a synonym ofR. pollinarias. str., and for var.humilis, a taxon of yet unknown affinity.


Zootaxa ◽  
2017 ◽  
Vol 4276 (1) ◽  
pp. 46 ◽  
Author(s):  
PAULA C. RODRIGUEZ-FLORES ◽  
ANNIE MACHORDOM ◽  
ENRIQUE MACPHERSON

The genus Fennerogalathea Baba, 1988 was known to contain two species: F. chacei Baba, 1988, the type species, from the Philippines, Taiwan and Indonesia and F. chirostyloides Tirmizi & Javed, 1993 from the Bay of Bengal. In the present study, three new species of the genus are described and illustrated: F. chani n. sp. from Papua New Guinea, F. cultrata n. sp. from New Caledonia and Vanuatu and F. ensifera n. sp. from Fiji. The new species are morphologically distinguishable on the basis of the shape and spination of the rostrum and the presence/absence of a small spine on the frontal margin of the carapace. The species also show clear genetic differences (COI and 16S rDNA) among them. 


2015 ◽  
Vol 8 ◽  
Author(s):  
Frano Kršinić

A new species of stephid calanoids copepodStephos grieveaesp. nov. was collected from an anchialine cave on Mljet Island (Croatia). The new species can be distinguished from otherStephosspp. by a combination of the following features: last pedigerous somite slightly asymmetrical, female genital double-somite symmetrical in ventral view, about as long as wide, single operculum; antennules of both sexes are symmetrical, 24-segmented and very long, reaching almost to end of anal somite; antennal exopod 7-segmented; maxillule displays 13 armature elements on praecoxal arthrite; female fifth legs symmetrical, uniramous and 3-segmented, terminal segment very long armed with spinules distally along inner and outer margins, single small spine on anterior surface and spiniform process laterally; male fifth legs are uniramous and asymmetrically, right leg 4-segmented and left 5-segmented, segment 4 not swollen and segment 5 simple, crescent shaped and is connected to segment 4 at approximately one quarter of its length. The shorter part of segment 5 tapers into a heavy process, while the longer part forms a club-shaped, curved extension.


Crustaceana ◽  
2014 ◽  
Vol 87 (4) ◽  
pp. 430-447
Author(s):  
Dara Ambedkar ◽  
Bandari Elia

A new species, Tropodiaptomus defayeae n. sp. from Nepal, is herein proposed for inclusion in the genus Tropodiaptomus. This is the first record of the genus from Nepal. The new species is described and illustrated based on two males and two females collected from a permanent freshwater pond in the village Ankidha near Khatmandu, Nepal. A critical comparison of the new species with its known congeners has revealed close similarity with Tropodiaptomus ruttneri (Brehm, 1923). However, it is distinguishable by characters of the male P5 such as: (1) a thick basipod in the right P5, which is as long as wide, and has an unusually large thumb-like hyaline lobe close to the inner margin on its posterior face; (2) a small spine and a narrow hyaline lamella on the inner margin; and (3) the basipod of the left P5 has a large hyaline lamella on the inner distal margin. Besides the description of T. defayeae, brief notes on the ecology and zoogeography of the genus are also given. A key for the identification of the Indian species of Tropodiaptomus, including also the new species, is provided at the end of this paper.


Zootaxa ◽  
2012 ◽  
Vol 3493 (1) ◽  
pp. 27 ◽  
Author(s):  
HYUCK JOON KWUN ◽  
JIN KOO KIM

A new species, Eulophias koreanus, belonging to the family Stichaeidae, suborder Zoarcoidei, is described on the basisof five specimens (70.7–160.7 mm in standard length) collected from the southern sea of Korea. The new species differsfrom the only two known congeneric species, Eulophias tanneri and Eulophias owashii, which are endemic to Japan. Eu-lophias koreanus is readily distinguished from E. tanneri by the numbers of anal-fin rays (102–103 vs. 75 in E. tanneri)and caudal-fin rays (9–10 vs. 7). Eulophias koreanus is more similar to E. owashii than to E. tanneri, but differs from theformer in the number of vertebrae (141–143 vs. 133 in E. owashii) and pectoral-fin length (36.1–39.5% of HL vs. 27.8%).Regarding the caudal skeletons in E. koreanus, the last dorsal pterygiophore is inserted between the last 1st and 2nd or the2nd and 3rd neural spines, and a small spine is absent on the ventral portion of the parhypural, whereas in E. owashii, thelast dorsal pterygiophore is inserted between the last 3rd and 4th neural spines, and a small spine is present on the ventralportion of the parhypural. Analyses of 500-bp sequences of mitochondrial DNA cytochrome oxidase subunit I providestrong evidence that the five new specimens belong to the same species, even though they show some variation in head shape.


HortScience ◽  
1992 ◽  
Vol 27 (6) ◽  
pp. 644f-644
Author(s):  
Thanda Wai ◽  
Jack Staub ◽  
Rebecca Grumet

TMG-1 is resistant to ZYMV and WMV-2, two closely related potyviruses. Resistance to ZYMV is due to a single recessive gene (Provvidenti, 1987); however, two recessive genes appear to confer resistance to WMV-2. We sought to further characterize the resistances by studying possible linkage relationships with physiological, morphological, electromorphic, and phytopathological markers. TMG-1, WI-2757 (an inbred line susceptible to both viruses), and their F2 progeny were screened for various single gene characters that differ between the two parents. Linkages reported in the literature were also observed in this study: (1) between bitterfree (bi) and female (F), and (2) between numerous spine (ns), small spine (ss), and tuberculate (Tu). New linkages detected were between: (1) resistance to WMV-2 and F, (2) resistance to WMV-2 and ZYMV, and (3) possibly resistance to ZYMV with fusarium and ns.


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