New well-preserved scleritomes of Chancelloriida from early Cambrian Guanshan Biota, eastern Yunnan, China

2018 ◽  
Vol 92 (6) ◽  
pp. 955-971 ◽  
Author(s):  
Jun Zhao ◽  
Guo-Biao Li ◽  
Paul A. Selden

AbstractA large number of well-preserved chancelloriid scleritomes from the Guanshan biota, early Cambrian of Yunnan, China, are described as a new species,Allonnia tenuisn. sp., and provide solid evidence for the original appearance of these enigmatic animals, based on specimens compacted laterally and top-down. With the assistance of a flexible integument, chancelloriids, especiallyAllonniafrom early and middle Cambrian, may have had the ability to partially or completely expand and contract the body, which might have played an important role in feeding. A new metazoan with single-element spines,Nidelric gaoloufangensisn. sp., is also described. Preservation and affinity are discussed. Detailed comparison of the morphology of the body and spines of this metazoan indicate that it shares many similarities with chancelloriids, of which it may be an unusual form.UUID:http://zoobank.org/2708d95a-1fae-46fc-afea-9707ae97a4d7

1992 ◽  
Vol 129 (4) ◽  
pp. 491-495 ◽  
Author(s):  
Rachel A. Wood ◽  
Kevin R. Evans ◽  
Andrey Yu. Zhuravlev

AbstractA new species of archaeocyath sponge, Dictyocyathus neptunensis, is described from the lower third of the Nelson Limestone of the Neptune Range, Antarctica. Based on the presence of the trilobites Nelsonia schesis and Amphoton oatesi, these strata are interpreted to be mid- to late middle Cambrian in age. D. neptunensis shows a branching, low integration modular form and a very simple skeletal type. Such an organization is predicted from known morphological trends within the early Cambrian Archaeocyatha. Specimens are not in life position, and probably form part of a storm deposit. The absence of Dictyocyathus from latest early Cambrian (Toyonian) strata worldwide suggests a convergent nature for this highly simplified skeletal type in archaeocyaths.


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.


Phytotaxa ◽  
2021 ◽  
Vol 509 (3) ◽  
Author(s):  
SHAHID NAWAZ LANDGE ◽  
RAJENDRA D. SHINDE

Ischaemum mistryi, a new species from the Sub-Tropical evergreen forest of Tilari Ghat, Maharashtra, India, is described and illustrated. This grass is unique with its leaves drooping, mostly congregated near the base, basal sheath villous, culms compressed at the base, lower glume of the sessile spikelet linear-lanceolate to oblongish tapering and slightly curled upwards, without a sub-apical ridge, nodules absent (if present 2–4 obscure) on its keels, and upper lemma of sessile spikelet bi-partite. Morphologically it is somewhat similar to I. mangaluricum, I. travancorense and I. barbatum. We provided a table of its detailed comparison with close species as mentioned above. According to IUCN Red List Categories and Criteria, we have assessed this new species as Critically Endangered (CR). The photo plates and illustration of the grass are given to facilitate its proper identification. A short discussion is also provided at the end.


Zootaxa ◽  
2021 ◽  
Vol 4941 (2) ◽  
pp. 239-258
Author(s):  
YUN-HE WU ◽  
XIAO-LONG LIU ◽  
WEI GAO ◽  
YU-FAN WANG ◽  
YING-CHUN LI ◽  
...  

Approximately half of the species in speciose genus Raorchestes were described during the past 10 years, yet only 11 species are known from Southeast Asia and southern China (SEA-SC), adjacent Himalayas, and northeastern India. Field work in northwestern Yunnan province, China resulted in the discovery of one new species in the genus based on morphological and molecular analyses. The new species is diagnosed by small size with 15.0–19.0 mm SVL in adult males (n=3); tongue pyriform, notched posteriorly; rudimentary webbing between toes; fingers and toes with narrow lateral dermal fringes; tibiotarsal articulation reaching anterior of the eye when hindlimb is stretched along the side of the body; relative finger lengths: I < II < IV < III, relative toe lengths: I < II < V < III < IV; inner metatarsal tubercle oval, outer metatarsal tubercle absent; finger discs and toe discs greyish or orange; flank near the crotch with a distinct black region between two creamy white patches, and the thigh having a similar black patch near the groin, proximal to another creamy white patch; a distinct “) (”-shaped dark marking on the back; male with external single subgular vocal sac; nuptial pad absent. A phylogenetic tree was reconstructed based on the mitochondrial genes for 16S rRNA and ND1. The results indicated that these individuals form a monophyletic group, and show high genetic divergence to their closest relatives within the genus (uncorrected p-distances > 3.2%) by distance of 16S comparable to the divergence between recognized Raorchestes species. This study further enriches the diversity of rhacophorids, especially in northwestern Yunnan. 


2014 ◽  
Vol 12 (2) ◽  
pp. 333-342 ◽  
Author(s):  
Angela M. Zanata ◽  
Priscila Camelier

Characidium samurai, a species of the family Crenuchidae apparently endemic to rio das Almas and rio Vermelho basins, Bahia, Brazil, is described. The new species is readily distinguishable from its congeners, except C. lanei, by having a dark lateral band along the head and body that is particularly broad from the rear of the head to the end of the caudal peduncle (1.5 or 2 scales wide) and by the absence of dark bars or blotches on the ventral half of the body. Characidium samurai differs from C. laneiby having the lateral band with straight borders overall (vs.lateral band with somewhat irregular borders due to blotches extending dorsally or ventrally), anal fin ii,7-8 (vs. ii,6), and 4 horizontal scale rows above the lateral line and 4 below (vs. 5/3). It further differs from congeners by a series of features, including isthmus completely covered by scales, lateral line complete with 34-37 perforated scales, 9 scales on the transversal line, 14 scale rows around the caudal peduncle, anal fin ii,7-8, and the absence of dark bars or spots on the fins, except by a faded dorsal-fin bar. The presence of pseudotympanum in four species of Characidium is discussed.


Zootaxa ◽  
2018 ◽  
Vol 4461 (3) ◽  
pp. 438
Author(s):  
CARLOS AUGUSTO FIGUEIREDO ◽  
CRISTIANO R. MOREIRA

A new species, Poecilia (Pamphorichthys) akroa, is described from the Rio Tocantins drainage, Brazil. The new species differs from the remaining species of the genus by the possession of 10 or 11 pectoral-fin rays, entire preopercular ramus and posterior portion of the supraorbital ramus of the cephalic sensory system enclosed in canals, a faint longitudinal band along the body, a single gonapophysis, a homogeneous reticulate color pattern on sides of body, urogenital region of females heavily pigmented, distalmost segments of the anterior branch (4a) of the fourth gonopodial ray fused into an elongated segment turned anteriorly, subdistal segments of anterior branch (5a) of fifth gonopodial ray simple, without anterior (ventral) projections, dorsal fin with pigmentation at its distal portion and with a basal black blotch, and chromatophores more concentrated on the posterior margin of the mid-ventral scale series of the caudal peduncle and ventrolateral margin of the adjacent scales forming a series of rhombi posterior to anal fin. 


1900 ◽  
Vol 7 (12) ◽  
pp. 560-561
Author(s):  
G. C. Crick

The name Nautilus clitellarius was given by J. de C. Sowerby to a Nautiloid from the Coal-measures, Coalbrookdale, Shropshire, and the description was accompanied by three figures, each representing a different specimen. In 1884 the species was included by Professor Hyatt in his new genus Ephippioceras. In 1891 Dr. A. H. Foord found a new species, Ephippioceras costatum, which was said to be “distinguished from E. clitellarium (to which it is, however, very closely related) by the character of the septa and by the surface ornaments. The septa in E. costatum do not form such an acute lobe upon the periphery as do those of E. clitellarium, and they are also a little wider apart in the former species than they are in the latter. Moreover, E. costatum is provided with prominent transverse costæ, which are strongest upon the sides of the shell where they swell out into heavy folds. These costæ are directed obliquely backwards, and cross the septa at an acute angle, passing across the periphery and forming a shallow sinus in the middle. None of the specimens in the British Museum have the test preserved, so that the ribbing has only been observed upon casts. The costæ are equally well developed upon the body-chamber and upon the septate part of the shell in the adult, but they were either very feeble or altogether absent in the young.” A re-examination of the specimens in the Museum collection shows that the separation of the two forms is quite justifiable.


Zootaxa ◽  
2004 ◽  
Vol 628 (1) ◽  
pp. 1 ◽  
Author(s):  
JONATHAN W. ARMBRUSTER

Pseudancistrus sidereus is described from two collections of specimens from Amazonas, Venezuela. Pseudancistrus sidereus differs from all other members of Pseudancistrus based on the presence of a unique keel on the caudal peduncle formed from the concave dorsal sections of the plates in the ventral series, light spots on the body (these may be yellow in life) centered on the body plates and the absence of the characteristics of the more derived members of Pseudancistrus such as hypertrophied odontodes along the snout in males and females and the loss of evertibility of the cheek plates. Pseudancistrus includes Lithoxancistrus and Guyanancistrus and is diagnosed by the following synapomorphies: no suture between pterotic-supracleithrum and hyomandibula, no contact of the hyomandibula with the prootic, straight, spoon-shaped anterior process of metapterygoid, nasal bone not much wider than laterosensory canal running through it, sphenotic not contacting posteriormost infraorbital externally, and a short ventral ridge on the pelvic basipterygium (lost in some species). Two species formerly assigned to Guyanancistrus are placed in different genera. Hypostomus guacharote is placed in Lasiancistrus and Chaetostomus trinitatis is placed in Ancistrus.Se describe Pseudancistrus sidereus, con base en dos colectas de espec menes del Amazonas venezolano. Pseudancistrus sidereus difiere de los otros miembros del g nero Pseudancistrus por la presencia de una quilla nica en el ped nculo caudal formada a partir de las secciones c ncavas dorsales de las placas de la serie ventral, puntos blancos en el cuerpo (probablemente amarillos en vida) centrados en las placas corporales y la ausencia de ciertas caracter sticas presentes en los miembros m s derivados de Pseudancistrus, como odontodos hiperatrofiados a lo largo del rostro en machos y hembras y la perdida de evertibilidad de las placas de la mejilla. Pseudancistrus incluye a Lithoxancistrus y Guyanancistrus y se diagnostica por las siguientes sinapomorf as: sutura entre el pter tico-supracleitro y la hiomand bula ausente, hiomand bula y pro tico sin contacto, proceso anterior del metapterigoides recto y en forma de cuchara, hueso nasal apenas m s amplio que el canal laterosensorial que corre a trav s del mismo, esfen tico sin contacto externo


2017 ◽  
Vol 15 (3) ◽  
Author(s):  
Juliano Ferrer ◽  
Laura M. Donin

ABSTRACT A new species of Ituglanis associated to the grasslands of the Pampa biome is described from the rio Uruguai basin, southern Brazil. The new species is distinguished from its congeners by the low number of ribs and by a unique color pattern composed of an outer layer with scattered round black blotches equivalent in size to the eye circumference over a reddish brown background on the lateral surface of the body. We provide the genetic sequences of the mitochondrial gene Cytochrome c Oxydase subunit I (COI) for three of the paratypes and discuss aspects about the recent discovery of the new species.


2018 ◽  
Vol 93 (1) ◽  
pp. 115-125
Author(s):  
John S. Peel

AbstractPhosphatic sclerites of the problematicTarimspiraYue and Gao, 1992 (Cambrian Series 2) recovered by weak acid maceration of limestones display a unique range of mainly strongly coiled morphologies. They were likely organized into multielement scleritomes, but the nature of these is poorly known; some sclerites may have had a grasping function.Tarimspirasclerites grew by basal accretion in an analogous fashion to younger paraconodonts (Cambrian Series 3–4) but lack a basal cavity. Based on proposed homologies,Tarimspiramay provide an extension of the early vertebrate paraconodont–euconodont clade back into the early Cambrian.Tarimspirais described for the first time from Laurentia (North Greenland), extending its known range from China and Siberia in Cambrian Series 2. In addition to the type species,Tarimspira planaYue and Gao, 1992, the Greenland record ofTarimspiraincludes two morphotypes of a new species,Tarimspira artemi.UUID:http://zoobank.org/c7c536c8-cdaf-49a9-ae1d-77c392f553fc.


Sign in / Sign up

Export Citation Format

Share Document