scholarly journals A new, “dwarfed” species of the phenacodontid “condylarth” Ectocion from the late Paleocene of Alberta, Canada, and its implications

2021 ◽  
pp. 1155-1169
Author(s):  
Marisol Montellano-Ballesteros ◽  
Richard C. Fox ◽  
Craig S. Scott

A large collection of dentigerous jaws quarried from the Gao Mine locality, late Paleocene, Paskapoo Formation, central Alberta, Canada, documents a new species of the early Paleogene phenacodontid “condylarth” Ectocion Cope, 1882. The new species, Ectocion stockeyae, the smallest of the genus, occurs well before the abrupt global warming at the Paleocene–Eocene Thermal Maximum, an event purportedly causing the rapid evolution of “dwarfed” mammals, including a species of Ectocion; however, there is no evidence of increased temperatures at Gao Mine to account for the small size of Ectocion stockeyae, raising questions of the relationship between temperature and body size in Ectocion. Ectocion stockeyae also exhibits sexual dimorphism of the canines, a pattern in mammals often associated with a population structure in which the males are relatively few and polygynous, resulting in intense male rivalry for mating success. The sample of Ectocion stockeyae from Gao Mine includes a substantial majority of “juvenile” individuals retaining deciduous posterior premolars, many even after eruption of the molars had been completed, suggesting short life spans, accelerated growth, and rapid dental development in this species as expressed in Schultz’s Rule.

2010 ◽  
Vol 47 (12) ◽  
pp. 1451-1462 ◽  
Author(s):  
Craig S. Scott

Mixodectidae (Mammalia, Archonta) are an unusual, poorly known family of dermopteran-like mammals that have been discovered at several North American localities of primarily early Paleocene age. Among the three or four recognized mixodectid genera, Eudaemonema Simpson is perhaps one of the least understood, being known from only a few localities of late Torrejonian and earliest Tiffanian age. This paper reports on a new species of Eudaemonema from the late Paleocene of Alberta, Canada, that significantly extends the geographic and stratigraphic ranges of the genus. Eudaemonema webbi sp. nov. is known from middle and late Tiffanian localities in central and south central Alberta, and it represents the youngest and northernmost species of Eudaemonema so far discovered. E. webbi differs from the genotypic species E. cuspidata in being larger and in having a suite of dental characters (e.g., molariform posterior premolars, enlarged molar protocone and hypocone, development of a second grinding platform on the lower molars) that suggests an increased emphasis on grinding during mastication. E. webbi possesses several dental features (e.g., broad, shelf-like molar paraconid–paracristid, lingually shifted molar hypoconulid) that resemble those of cynocephalids (Mammalia, Dermoptera), with these resemblances interpreted herein as convergent. The occurrence of E. webbi at Gao Mine extends the stratigraphic range of Eudaemonema into the late Tiffanian (Ti5) and represents the youngest known record of Mixodectidae.


Phytotaxa ◽  
2018 ◽  
Vol 349 (1) ◽  
pp. 61
Author(s):  
LUÍS ADRIANO FUNEZ ◽  
EMERSON RICARDO PANSARIN

Cleistes pallida, a new species of Orchidaceae, is described and illustrated. The relationship of this new species to other taxa of the genus are discussed.


1995 ◽  
Vol 8 (6) ◽  
pp. 1035 ◽  
Author(s):  
LJ Scriven ◽  
RS Hill

The oldest known Casuarinaceae macrofossils, from late Paleocene sediments at Lake Bungarby in New South Wales, are assigned to a new species of Casuarinaceae, Gymnostoma antiquum. The nearest living relatives of this species are the Papua New Guinean Gymnostoma species and in particular one as yet unnamed species. Previous problems relating to the preparation, identification and description of Casuarinaceae macrofossils are examined and clarified. The ecology of both living Gymnostoma and G. antiquum are discussed. The decrease in catastrophic disturbance and climate seasonality during the Cenozoic were probably major contributing factors leading to the current distribution of Gymnostoma.


2017 ◽  
Vol 22 (9) ◽  
pp. 1431
Author(s):  
Elizeu B. Castro ◽  
Ronald Ochoa ◽  
Reinaldo J.F. Feres

A new species, Terminalichus simplex sp. nov., is described based on adult females, deutonymphs and protonymphs, collected on Terminalia catappa L. (Combretaceae) from Thailand. The relationship of Terminalichus with other brevipalpine genera is discussed and a key to species of Terminalichus, Tenuilichus, Amblypalpus, Colopalpus and Priscapalpus is provided.  


Zootaxa ◽  
2017 ◽  
Vol 4303 (3) ◽  
pp. 417 ◽  
Author(s):  
LUIS PÉREZ ◽  
MARYZENDER RODRÍGUEZ ◽  
ANGÉLICO ASENJO

A new species of the genus Piestus Gravenhorst is described from Peru, P. chullachaqui sp. nov. (Cuzco). Photographs and drawings of the major diagnostic characters are provided. A key to Piestus species is modified to include the new species. New records are provided for Piestus angularis Fauvel, Piestus bicornis (Olivier), Piestus fronticornis (Dalman), Piestus lacordairei Laporte, Piestus longipennis (Fauvel), Piestus mexicanus Laporte, Piestus minutus Erichson, Piestus pennicornis Fauvel, Piestus spinosus (Fabricius), Piestus sulcatus Gravenhorst, Piestus surrufus Caron et al. and Piestus validus Sharp. Cladistic analysis is made to know the relationship of the P. chullachaqui sp. nov. within Piestus.  


2021 ◽  
Author(s):  
Tatiana S. Leite ◽  
Erica A.G. Vidal ◽  
Françoise Dantas Lima ◽  
Sergio M.Q. Lima ◽  
Ricardo M Dias ◽  
...  

Abstract The new species, Paroctopus cthulu sp. nov. Leite, Haimovici, Lima and Lima, was recorded from very shallow coastal waters on sandy/muddy and shelter-poor bottoms with natural and human-origin debris. It is a small octopus, adults are less than 35 mm mantle length (ML) and weigh around 15 g. It has short to medium sized arms, enlarged suckers on the arms of both males and females, large posterior salivary glands (25 %ML), a relatively large beak (9 % ML) and medium to large mature eggs (3.5 to > 9 mm). The characteristics of hatchlings of two brooding females, some of their anatomical features, and in-situ observations of their behaviour are a clue to the life history of it and closely related pygmy octopuses. The Bayesian phylogenetic analysis showed that Paroctopus cthulu sp.nov. specimens grouped in a well-supported clade of Paroctopus species, separate from P.joubini and P. cf mercatoris from the Northwestern Atlantic . The description of this new species, living in a novel habitat of human debris in shallow water off Brazil, offered an opportunity not only to evaluate the relationship among the small octopuses of the western Atlantic, Caribbean and eastern Pacific, but also their adaptation to the Anthropocene period.


Phytotaxa ◽  
2019 ◽  
Vol 407 (1) ◽  
pp. 59-70 ◽  
Author(s):  
YI TONG ◽  
DAI-KE TIAN ◽  
JIANG-PING SHU ◽  
YAN XIAO ◽  
BING-MOU WANG ◽  
...  

Begonia yizhouensis, a new species in Begonia sect. Coelocentrum (Begoniaceae) from Guangxi of China, is described and illustrated. Morphologically, it is similar to the adjacently distributed B. luochengensis, but clearly separated by its waxy leaves with glabrous or sometimes sparsely puberulous surfaces, larger variation in leaf color and maculation along the main veins, white to pinkish-white flowers and late flowering. Furthermore, molecular phylogenetic analysis indicated B. yizhouensis was a monophyletic lineage and was sister with B. luochengensis. The relationship of the new species and other similar species is also discussed. This new species is endemic to limestone hills in Guangxi and is assessed as “Endangered” (EN) according to the IUCN Red List Categories and Criteria. Additionally, morphological and molecular evidence for B. yishanensis not being synonymous with B. porteri is presented.


Phytotaxa ◽  
2017 ◽  
Vol 311 (2) ◽  
pp. 195 ◽  
Author(s):  
RUN-ZHENG CHEN ◽  
WEN-HONG CHEN ◽  
YI-GANG WEI ◽  
FANG WEN ◽  
XUN-LIN YU ◽  
...  

Oreocharis crispata, a new species of Oreocharis (Gesneriaceae) from northeastern Guangxi, China, is described and illustrated. The new species is compared with its most morphologically similar species O. nemoralis and O. magnidens. Besides, the relationship between the new species and Oreocharis × heterandra is discussed here.


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