scholarly journals Aulacoseira giraffensis (Bacillariophyceae), a new diatom species forming massive populations in an Eocene lake

2019 ◽  
Vol 152 (2) ◽  
pp. 358-367 ◽  
Author(s):  
Peter A. Siver ◽  
Alexander P. Wolfe ◽  
Mark B. Edlund ◽  
Joel Sibley ◽  
Josh Hausman ◽  
...  

Background and aims – Diatoms began to inhabit freshwater by at least the Late Cretaceous, becoming well established by the early to middle Eocene. Aulacoseira, an important diatom in numerous ponds, lakes and rivers today, was one of the earliest known genera to colonize freshwater ecosystems. Members of this genus with characteristics familiar to those found on modern species became increasingly more abundant by the Eocene, and continued to thrive throughout the Miocene to the present. We describe a new species of Aulacoseira from an early to middle Eocene site near the Arctic Circle in northern Canada. Methods – Twelve samples taken from the Giraffe Pipe core were analysed in this study. Light and scanning electron microscopy were used to document morphological characters. Morphometric measurements were made from 200 specimens per sample (n = 1200), and used to investigate changes in valve size over time. Key results – The new species, Aulacoseira giraffensis, has valves with a length:width ratio close to 1, a hyaline valve face, straight mantle striae, a shallow ringleiste, branched linking spines, concave-convex complementarity on adjacent valve faces, and rimoportulae with simple papillae-like structure. The suite of characters, especially the highly branched spines, concave-convex valves and simple rimoportulae, is unique for this species. Large numbers of A. giraffensis specimens were found over a ten-metre section of the core, representing thousands of years. These high concentrations are indicative of abundant, bloom-like, growth. Conclusions – The locality represents one of the earliest known records of Aulacoseira dominating a freshwater community. Findings confirm that the morphological body plan for the genus was well established by the Eocene. Although findings indicate evolutionary stasis in morphological structure for A. giraffensis over a time scale of thousands of years, oscillations in valve morphometrics could potentially be used to trace changes in the environment of this ancient Arctic waterbody.

2020 ◽  
Vol 29 (1) ◽  
pp. 138-154
Author(s):  
R.V. Smirnov ◽  
O.V. Zaitseva ◽  
A.A. Vedenin

A new species of Pogonophora obtained from one station at a depth of 25 m from near the Dikson Island in the Kara Sea is described. Galathealinum karaense sp. nov. is one of the largest pogonophorans, the first known representative of the rare genus Galathealinum Kirkegaard, 1956 in the Eurasian part of the Arctic Ocean and a highly unusual finding for the desalted shallow of the Yenisey Gulf. Several characters occurring in the new species are rare or unique among the congeners: under-developed, hardly discernible frills on the tube segments, extremely thin felted fibres in the external layer of the tube, and very faintly separated papillae in the anterior part of the trunk. Morphological characters useful in distinguishing species within the genus Galathealinum are defined and summarised in a table. Diagnosis of the genus Galathealinum is emended and supplemented by new characters. Additionally, three taxonomic keys are provided to the species of Galathealinum and to the known species of the Arctic pogonophorans using either animals or their empty tubes only, with the brief zoogeographical information on each Arctic species.


2021 ◽  
Vol 24 (3) ◽  
pp. 236-244
Author(s):  
Claudia Herrera ◽  
Graciela Esteban ◽  
Daniel Alfredo Garcia-Lopez ◽  
Virginia Deraco ◽  
Judith Babot ◽  
...  

We describe isolated remains of a Paleogene cingulate from El Simbolar locality, Upper Lumbrera Formation (Bartonian), southern Salta Province, northwestern Argentina. The material consists of numerous fixed, movable, and caudal sheath osteoderms. The specimen has large-sized osteoderms, with a lageniform main figure, as in Utaetus buccatus, U. laxus, U. argos, ?U. deustus, Punatherium catamarcensis, and the basal euphractin Archaeutatus. The combination of morphological characters, in addition to its large size, allows us to recognize a new species of “Utaetini” for the Paleogene of northwestern Argentina. This new species of ?Utaetus represents the oldest record of Euphractinae in this region, and strengthens the endemic condition of its Paleogene faunas. Keywords: Cingulata, osteoderms, El Simbolar, Paleogene, Salta, Argentina.


2003 ◽  
Vol 16 (4) ◽  
pp. 487 ◽  
Author(s):  
Brendan J. Smith ◽  
K. Sivasithamparam

Ganoderma, a genus of approximately 214 described species has been deemed to be in taxonomic chaos. The difficulties stem from the large numbers of synonymies, widespread misuse of names, typification problems and a paucity of reliable morphological characters. In Australia, all of these problems are represented and the genus is in need of revision. In this study six species of Ganoderma were identified among several collections. A new species, G. steyaertanum sp. nov., is described from Australian and Indonesian material. This species has been commonly mistaken for G. lucidum, a species which is probably restricted to Europe and from which G.�steyaertanum is genetically distinct. The remaining species were determined to be G. boninense, G. cupreum, G.�incrassatum (a name which has not recently featured in literature), G. australe and G. weberianum. All were verified against type material except G. australe, which is in need of neotypification as the type is lost. G. tornatum, a widely accepted synonym, may take precedence; however, we have been unable to examine the type for verification. Based on morphology, G. polymorphum was identified as a synonym of G. cupreum. On the basis of morphology and previously published rDNA sequence studies, G. microsporum was considered a synonym of G.�weberianum. A seventh species, G. colossum, has also been reported from Australia; however the specimen was not available for verification in this study.


2020 ◽  
Vol 45 (2) ◽  
pp. 328-333
Author(s):  
Camila Alcantara ◽  
Gleison Soares ◽  
Francisco de Assis Ribeiro dos Santos ◽  
Marccus Alves

Abstract—Justicia rubrobracteata, a new species from northeastern Brazil, is described and illustrated. The new species is morphologically similar to J. aequilabris due to its shrubby habit, and terminal and axillary spicate inflorescences with red flowers. However, J. rubrobracteata is differentiated mainly by the shape and color of its bracts and bracteoles as well as an orangish macula in the corolla, and a torulose capsule. In addition, J. rubrobracteata is only known from northeastern Brazil, from the states of Paraíba and Rio Grande do Norte, while J. aequilabris is widely distributed in Bolivia, Brazil, and Paraguay. A table with the main morphological characters of both species is included, as well as photographs, a key to species of Justicia for the states of Paraíba and Rio Grande do Norte in northeastern Brazil, a distribution map of both species, and conservation data for the new species.


2011 ◽  
Vol 20 (1) ◽  
pp. 85-95 ◽  
Author(s):  
S.A. Belokobylskij ◽  
T.S. Kostromina

Two braconid genera from the subfamily Alysiinae, Lodbrokia Hedqvist, 1962 and Asyntactus Marshall, 1898, are recorded in the fauna of Russia and in the Asian continent for the first time. A new species Lodbrokia uralica sp. nov. is described from the Urals, and a key to species of this genus is provided. Redescriptions of the female and male of Asyntactus rhogaleus Marshall, 1898 with information about the level of variability of its morphological characters are given. Asyntactus sigalphoides Marshall, 1898 is synonymised with A. rhogaleus Marshall, 1898 (syn. nov.).


2019 ◽  
Vol 27 (4) ◽  
pp. 238-247
Author(s):  
Massoud Ranjbar ◽  
Narges Rahchamani

Scrophularia dianatnejadii Ranjbar & Rahchamani, a new species from Tehran Province in northern Iran, is described and illustrated. It is closely related to S. amplexicaulis Benth. and shares with it some diagnostic morphological characters such as habit, plant indument, phyllotaxy, and corolla shape and color. Both species are placed in Scrophularia L. sect. Mimulopsis Boiss. Macro- and micromorphological characters of the two are examined and compared. Pollen morphology of these species is investigated using SEM. Detailed descriptions, illustrations, distribution maps, and conservation status of both species are provided.


Zootaxa ◽  
2021 ◽  
Vol 4927 (2) ◽  
pp. 197-208
Author(s):  
FRANCESCO BALLARIN ◽  
TAKESHI YAMASAKI ◽  
YONG-CHAO SU

Representatives of some poorly known spider species collected in the rainforest litter of the Orchid Island (Taiwan) are illustrated and discussed here. A new species, Brignoliella tao sp. nov. (Fam. Tetrablemmidae), endemic to Orchid Island, is described based on both sexes. The previously unknown female of Theridiosoma triumphale Zhao & Li, 2012 (Fam. Theridiosomatidae), is described for the first time. Zoma taiwanica (Zhang, Zhu & Tso 2006) comb. nov., from the same family, is illustrated and its transfer from the genus Theridiosoma O. Pickard-Cambridge, 1879 to Zoma Saaristo, 1996 is proposed on the basis of morphological characters. Habitus and genitalia of the endemic species Gongylidioides angustus Tu & Li, 2006 (Fam. Linyphiidae) are also illustrated. 


Zootaxa ◽  
2015 ◽  
Vol 3919 (1) ◽  
pp. 192
Author(s):  
M. VALOIS ◽  
F. SILVA

Golinca trevisani Valois & Silva, new species (Coleoptera: Scarabaeidae: Cetoniinae: Trichiini: Incina) from Ouro Preto do Oeste, Rondônia, and Amazonas, Brazil is described, representing the first record of the genus Golinca for Brazil. Diagnosis, illustrations of key morphological characters, the first male genitalia description in the genus, and a key for identification of four species of Golinca are provided. 


Nematology ◽  
2018 ◽  
Vol 20 (7) ◽  
pp. 653-669 ◽  
Author(s):  
Oleg Gorgadze ◽  
Elena Fanelli ◽  
Manana Lortkhipanidze ◽  
Alberto Troccoli ◽  
Medea Burjanadze ◽  
...  

Summary A new species of entomopathogenic nematode, Steinernema borjomiense n. sp., was isolated from the body of the host insect, Oryctes nasicornis (Coleoptera: Scarabaeidae), in Georgia, in the territory of Borjomi-Kharagauli. Morphological characters indicate that the new species is closely related to species of the feltiae-group. The infective juveniles are characterised by the following morphological characters: body length of 879 (777-989) μm, distance between the head and excretory pore = 72 (62-80) μm, pharynx length = 132 (122-142) μm, tail length = 70 (60-80) μm, ratio a = 26.3 (23.0-29.3), H% = 45 (40-51), D% = 54 (47-59), E% = 102 (95-115), and lateral fields consisting of seven ridges (eight incisures) at mid-body. Steinernema borjomiense n. sp. was molecularly characterised by sequencing three ribosomal regions (the ITS, the D2-D3 expansion domains and the 18S rRNA gene) and the mitochondrial COI gene. Phylogenetic analyses revealed that S. borjomiense n. sp. differs from all other known species of Steinernema and is a member of the monticolum-group.


2021 ◽  
Vol 50 (2) ◽  
pp. 319-326
Author(s):  
Süleyman Doğu ◽  
Yavuz Bağci

Stachys ahmet-savranii Doğu & Bağcı sp. nov. (Lamiaceae) from the Niğde (C5 Niğde, Turkey) is described and illustrated. It exhibits general features of the section Infrarosularis. It is closely related to Stachys citrina Boiss. & Heldr. but differs by its slender and unbranched stem; leaves structure; floral leaves equalling or longer than verticillasters; verticillester with 8 - 12 flowered and corolla 10 - 18 mm; Bracteoles reaching nearly middle of calyx tube. Diagnostic morphological characters are discussed. The geographical distribution of the new species is mapped. Notes are also presented on its ecology, biogeography and conservation status. Bangladesh J. Bot. 50(2): 319-326, 2021 (June)


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