scholarly journals A new fossil mantis shrimp and the convergent evolution of a lobster-like morphotype

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11124
Author(s):  
Carolin Haug ◽  
Joachim T. Haug
Keyword(s):  
New Species ◽  
Evolutionary Theory ◽  
Convergent Evolution ◽  
Morphological Diversity ◽  
Mantis Shrimp ◽  
Stem Species ◽  
Set Up ◽  
Stepwise Evolution ◽  
Modern Evolutionary Theory ◽  
A New Species

Eumalacostracan crustaceans all have a more or less stereotypic body organisation in the sense of tagmosis. Originally, this included a head with six segments (ocular segment plus five appendage-bearing segments), a thorax region with eight segments, and a pleon with six segments. Interestingly, despite these restrictions in variability in terms of tagmosis, the morphological diversity within Eumalacostraca is rather high. A group providing representative examples that are commonly known is Decapoda. Decapodan crustaceans include shrimp-like forms, lobster-like forms and crab-like forms. The stem species of Eucarida, the group including Decapoda and Euphausiacea, presumably possessed a rather shrimp-like morphology, quite similar to the stem species of Eumalacostraca. Also two other lineages within Eumalacostraca, namely Hoplocarida (with the mantis shrimps as modern representatives) and Neocarida (with the sister groups Thermosbaenacea and Peracarida) evolved from the shrimp-like body organisation to include a lobster-like one. In this study, we demonstrate that the stepwise evolution towards a lobster morphotype occurred to a certain extent in similar order in these three lineages, Hoplocarida, Eucarida and Peracarida, leading to similar types of derived body organisation. This evolutionary reconstruction is based not only on observations of modern fauna, but especially on exceptionally preserved Mesozoic fossils, including the description of a new species of mantis shrimps bridging the morphological gap between the more ancestral-appearing Carboniferous forms and the more modern-appearing Jurassic forms. With this, Mesozoic eumalacostracans represent an important (if not unique) ‘experimental set-up’ for research on factors leading to convergent evolution, the understanding of which is still one of the puzzling challenges of modern evolutionary theory.

scholarly journals Adocus Kohaku, A New Species of Aquatic Turtle (Testudines: Cryptodira: Adocidae) from the Late Cretaceous of Kuji, Iwate Prefecture, Northeast Japan, with Special References to the Geological Age of the Tamagawa Formation (Kuji Group) LSID urn:lsid:zoobank.org:act:61376EEE-A386-416E-98AE-FF64FE2597A2

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Ren Hirayama
Keyword(s):  
New Species ◽  
Late Cretaceous ◽  
Morphological Diversity ◽  
Eastern Asia ◽  
Geological Age ◽  
Iwate Prefecture ◽  
A New Species

A nearly complete shell of the genus Adocus (Adocidae; Pan-Trionychia; Cryptodira; Testudines) was collected from the late Cretaceous (Turonian) Tamagawa Formation of Kuji Group at Kuji City, Iwate Prefecture, northeast Japan. This turtle shows unique features such as the loss of cervical scute, extreme expansion of marginal scutes overlying costal plates, and exclusion of the humeral- pectoral sulcus from entoplastron. Thus, A. kohaku is erected as a new species. As A. kohaku shows most derived position of A. kohaku within this genus, morphological diversity of the genus Adocus seems to have occurred rather early in its evolution in Eastern Asia.

A new species of Largocephalosaurus (Diapsida: Saurosphargidae), with implications for the morphological diversity and phylogeny of the group

2013 ◽  
Vol 151 (1) ◽  
pp. 100-120 ◽  
Author(s):  
CHUN LI ◽  
DA-YONG JIANG ◽  
LONG CHENG ◽  
XIAO-CHUN WU ◽  
OLIVIER RIEPPEL
Keyword(s):  
New Species ◽  
Type Species ◽  
Morphological Diversity ◽  
Transverse Process ◽  
Sister Group ◽  
The Body ◽  
Current Evidence ◽  
Diagnostic Features ◽  
Additional Information ◽  
A New Species

AbstractLargocephalosaurus polycarpon Cheng et al. 2012a was erected after the study of the skull and some parts of a skeleton and considered to be an eosauropterygian. Here we describe a new species of the genus, Largocephalosaurus qianensis, based on three specimens. The new species provides many anatomical details which were described only briefly or not at all in the type species, and clearly indicates that Largocephalosaurus is a saurosphargid. It differs from the type species mainly in having three premaxillary teeth, a very short retroarticular process, a large pineal foramen, two sacral vertebrae, and elongated small granular osteoderms mixed with some large ones along the lateral most side of the body. With additional information from the new species, we revise the diagnosis and the phylogenetic relationships of Largocephalosaurus and clarify a set of diagnostic features for the Saurosphargidae Li et al. 2011. Largocephalosaurus is characterized primarily by an oval supratemporal fenestra, an elongate dorsal ‘rib-basket’, a narrow and elongate transverse process of the dorsal vertebrae, and the lack of a complete dorsal carapace of osteoderms. The Saurosphargidae is distinct mainly in having a retracted external naris, a jugal–squamosal contact, a large supratemporal extensively contacting the quadrate shaft, a leaf-like tooth crown with convex labial surface and concave lingual surface, a closed dorsal ‘rib-basket’, many dorsal osteoderms, a large boomerang-like or atypical T-shaped interclavicle. Current evidence suggests that the Saurosphargidae is the sister-group of the Sauropterygia and that Largocephalosaurus is the sister-group of the Saurosphargis–Sinosaurosphargis clade within the family.

Revisiting the diversity of Ludioctenus Fairmaire (Elateridae: Agrypninae), with description of a new species from Afghanistan, and discussion on the systematic position of Tetrigusina

Zootaxa ◽  
2018 ◽  
Vol 4455 (2) ◽  
pp. 377 ◽  
Author(s):  
ROBIN KUNDRATA ◽  
ELISKA SORMOVA ◽  
ALEXANDER S. PROSVIROV
Keyword(s):  
New Species ◽  
Eastern Mediterranean ◽  
Morphological Diversity ◽  
Systematic Position ◽  
Identification Key ◽  
Diagnostic Characters ◽  
First Time ◽  
A New Species

The genus Ludioctenus Fairmaire, 1893 hitherto included only L. cyprius (Baudi di Selve, 1871) from the eastern Mediterranean and L. pakistanicus Schimmel & Tarnawski, 2012 from Pakistan. Here, we describe L. afghanicus sp. nov. from the Nuristan Province in eastern Afghanistan. The distribution and morphological diversity of Ludioctenus is discussed, main diagnostic characters for all species are figured, and an identification key to the species of this genus is provided. Female pregenital segments and genitalia are figured for the first time for Ludioctenus, and the systematic position of this genus and its relatives is discussed.

New data on gastropod genus Hirsuticyclus (Caenogastropoda, Cyclophoridae) from mid-Cretaceous Kachin amber

2021 ◽  
pp. SP521-2021-127
Author(s):  
Tingting Yu
Keyword(s):  
New Species ◽  
Type Species ◽  
Morphological Characteristics ◽  
Morphological Diversity ◽  
First Record ◽  
Land Snail ◽  
Generic Diagnosis ◽  
Burmese Amber ◽  
New Material ◽  
A New Species

AbstractThe genus Hirsuticyclus Neubauer, Xing & Jochum, 2019 was the first record of an exceptionally preserved land snail with dense periostracal hairs from mid-Cretaceous Kachin (Burmese) amber. Here we document four newly-discovered shells from Kachin amber, one belonging to the type species Hirsuticyclus electrum Neubauer, Xing & Jochum, 2019 and the remaining three shells belonging to a new species, Hirsuticyclus canaliculatus sp. nov. Well-preserved morphological characteristics of these two species could be clearly demonstrated under light microscopy combined with modern micro-CT scans with computer 3D reconstructions. Our new material of the type species amends the generic diagnosis based on a better-preserved shell including the peristome and operculum. The new species shows distinctive shell characteristics such as numerous spiral keels and a flaring, folded peristome interrupted by two canals. These excellently preserved fossils contribute to our understanding of the morphological diversity and evolution of these ancient members of cyclophoroids.

scholarly journals The debated question of asymmetrical rhynchonellids (Brachiopoda, Rhynchonellida): examples from the Late Cretaceous of Western Europe

2020 ◽  
Vol 191 ◽  
pp. 1
Author(s):  
Danièle Gaspard ◽  
Sylvain Charbonnier
Keyword(s):  
New Species ◽  
Late Cretaceous ◽  
Western Europe ◽  
Anterior Margin ◽  
Morphological Diversity ◽  
New Genera ◽  
New Material ◽  
A New Species ◽  
Se France ◽  
Sw France

Many Cretaceous asymmetrical rhynchonellid brachiopods (Brachiopoda, Rhynchonellida) have long been considered as Rhynchonella difformis (Valenciennes in Lamarck, 1819). After a revision, Owen (1962) included the Cenomanian specimens from Europe in Cyclothyris M’Coy, 1844. Later, Manceñido et al. (2002) confirmed this decision and critically mentioned the name of another asymmetrical rhynchonellid genus from Spain, Owenirhynchia Calzada in Calzada and Pocovi, 1980. Specimens with an asymmetrical anterior margin (non particularly ecophenotypical), from the Late Coniacian and the Santonian of Les Corbières (Aude, France) and Basse-Provence (SE France) are here compared to specimens of the original Cenomanian species C. difformis. They are also compared to new material from the Northern Castilian Platform (Coniacian-Santonian, N Spain) and to Rhynchonella globata Arnaud, 1877 (Campanian, Les Charentes, Dordogne, SW France) and Rh. vesicularis Coquand, 1860 (Campanian, Charente, SW France). These observations document the great morphological diversity among all these species and lead us to erect a new species: Cyclothyris grimargina nov. sp. from the type material of Arnaud, and two new genera: Contortithyris nov. gen. including Contortithyris thermae nov. sp., Beaussetithyris nov. gen. including Beaussetithyris asymmetrica nov. sp. All of these brachiopods fundamentally present an asymmetrical state which origin is discussed.

scholarly journals Morphological diversity of habrobathynellids (Parabathynellidae, Bathynellacea) in India, with the description of a new species

2005 ◽  
Vol 39 (24) ◽  
pp. 2217-2224 ◽  
Author(s):  
Ranga Y. Reddy ◽  
Horst Kurt Schminke
Keyword(s):  
New Species ◽  
Morphological Diversity ◽  
A New Species

A new species of Pygopus (Pygopodidae; Gekkota; Squamata) from north-eastern Queensland

Zootaxa ◽  
2010 ◽  
Vol 2578 (1) ◽  
pp. 47 ◽  
Author(s):  
PAUL M. OLIVER ◽  
PATRICK COUPER ◽  
ANDREW AMEY
Keyword(s):  
New Species ◽  
Morphological Diversity ◽  
Genetic Data ◽  
Lower Number ◽  
Evolutionary Divergence ◽  
Isolated Populations ◽  
South Eastern ◽  
North Eastern ◽  
A New Species ◽  
Geographically Isolated

Based on a combination of morphological and genetic data, geographically isolated populations of Pygopus from northeastern Queensland, formerly referred to Pygopus lepidopodus (Lacépède), are herein described as a new species. Pygopus robertsi sp. nov. can be diagnosed from its congeners by a suite of scalation characters, including fewer keeled dorsal scales, presence of a single continuous row of supracilaries and a lower number of midbody scale rows. It is also deeply divergent genetically from samples of Pygopus lepidopodus from southern Australia. The known distribution of Pygopus robertsi sp. nov. is similar to that of a number of taxa centred upon relatively dry ecotonal habitats at the western edge of the rainforest blocks of north-eastern Queensland. Additional samples and systematic work will be required to examine the evolutionary divergence of apparently isolated populations of the new species, and the significance of considerable genetic and morphological diversity within remaining populations of Pygopus lepidopodus from south-eastern and southern Australia.

scholarly journals Homatula guanheensis sp. nov. (Teleostei: Nemacheilidae), a new species of loach from Henan Province, China

2021 ◽  
Vol 9 ◽  
Author(s):  
Chuanjiang Zhou ◽  
Wenwen Ma ◽  
Xi Wang ◽  
Yongtao Tang ◽  
Xiaoling Meng ◽  
...  
Keyword(s):  
New Species ◽  
Yangtze River ◽  
Yellow River ◽  
Henan Province ◽  
The Body ◽  
Valid Species ◽  
The Yangtze River ◽  
River Drainage ◽  
Set Up ◽  
A New Species

The genus Homatula belongs to the order Cypriniformes and family Nemacheilidae. Nichols (1925) set up the genus as a subgenus of Barbatula by the type species of Nemacheilus potanini. Currently, it is recognised as a valid genus. Nineteen valid species have been already reported in the drainage of the Yellow, Yangtze, Pearl, Lancang, Red and Nujiang Rivers. H. variegata, H. longidorsalis, H. berezowskii and H. potanini are distributed in the Yangtze River drainage in China. H. laxiclathra is mainly distributed in the Weihe River, a tributary of the Yellow River. The remaining species are mainly distributed in the rivers of Yunnan Province. Homatula guanheensis sp. nov., a new species, is described from the Guanhe River of the HanJiang River drainage (a tributary of the Yangtze River), Xixia County, Henan Province, China. It can be distinguished from its congeners by a combination of the following characters: the vertical brown bars on the body are wider than their interspaces, numbering 19–22; predorsal body partially scaled; the lateral line complete; adipose crest on caudal peduncle not reaching forward; the position of the anal-fin origin and the intestinal form. The new species displays distinct molecular divergence in the Cytochrome oxidase I (COI) and Cytochrome b (Cyt b) genes.

scholarly journals Integrative taxonomy reveals a new species of pacu (Characiformes: Serrasalmidae: Myloplus) from the Brazilian Amazon

2020 ◽  
Vol 18 (1) ◽  
Author(s):  
Rafaela Priscila Ota ◽  
Valéria Nogueira Machado ◽  
Marcelo C. Andrade ◽  
Rupert A. Collins ◽  
Izeni Pires Farias ◽  
...  
Keyword(s):  
New Species ◽  
Lateral Line ◽  
Amazon Basin ◽  
Morphological Diversity ◽  
Common Species ◽  
Color Pattern ◽  
Integrative Taxonomy ◽  
Striking Similarity ◽  
Species Discovery ◽  
A New Species

ABSTRACT Pacus of the genus Myloplus represent a formidable taxonomic challenge, and particularly so for the case of M. asterias and M. rubripinnis, two widespread and common species that harbor considerable morphological diversity. Here we apply DNA barcoding and multiple species discovery methods to find candidate species in this complex group. We report on one well-supported lineage that is also morphologically and ecologically distinct. This lineage represents a new species that can be distinguished from congeners by the presence of dark chromatophores on lateral-line scales, which gives the appearance of a black lateral line. It can be further diagnosed by having 25-29 branched dorsal-fin rays (vs. 18-24), 89-114 perforated scales from the supracleithrum to the end of hypural plate (vs. 56-89), and 98-120 total lateral line scales (vs. 59-97). The new species is widely distributed in the Amazon basin, but seems to have a preference for black- and clearwater habitats. This ecological preference and black lateral line color pattern bears a striking similarity to the recently described silver dollar Metynnis melanogrammus.

A new species of Andinia (Orchidaceae, Pleurothallidinae) from Huánuco, Peru, and the first Peruvian locality for Andinia schizopogon

Phytotaxa ◽  
2018 ◽  
Vol 361 (2) ◽  
pp. 222
Author(s):  
ALEX GUSTAVO DIAZ HERNÁNDEZ ◽  
LUIS ANTONIO OCUPA HORNA ◽  
LUIS ENRIQUE YUPANQUI GODO ◽  
MARK WILSON
Keyword(s):  
New Species ◽  
Convergent Evolution ◽  
National Park ◽  
Floral Morphology ◽  
Similar Species ◽  
Species Pair ◽  
Pollination Syndromes ◽  
A New Species

A new species of Andinia in subgenus Andinia from Tingo María National Park is described, illustrated and compared to the most similar species pair.  Andinia tingomariana is distinguished by unguiculate, reniform, ciliate petals, a longer column without the terminal dilation and a trilobed, ciliate lip in which the narrow, semi-auriculate lateral lobes project upward around the column, adnate in the middle, creating a furrowed surface. The floral morphology of the new species is compared to that of the phylogenetically unrelated Salpistele group of Stelis and possible convergent evolution of pollination syndromes is discussed. Finally, the first confirmed locality of A. schizopogon is reported and a preliminary list of Andinia species in Peru is provided.

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