Unique Combination Of Characters Research Articles

Filling the gap in the evolution of the genus Echinochara Peck (Clavatoraceae, Charophyta)

Echinochara is a poorly known charophyte genus of the extinct family Clavatoraceae that thrived in the Middle Jurassic–Early Cretaceous of North America, Europe, and North Africa. It represents the most ancient and plesiomorphic genus of this family. However, the fossil record of Echinochara is discontinuous, showing several gaps, one of them especially significant in evolutionary terms between the Kimmeridgian and the early Barremian. The new species Echinochara pontis sp. nov., described here from the late Berriasian of the Maestrat Basin (NE Spain), bridges, in part, this gap, shedding light on the evolution of the genus during the earliest Cretaceous. The fructification (utricle) has bilateral symmetry, formed by two superimposed series of bract cells that abaxially cover the gyrogonite. The inner series has three long cells that are born by a short basal cell and reach the oospore apex. The outer series shows a central fan of bract cells, composed of a small basal cell, triangular in shape, that bears three long cells growing upwards, which are in turn flanked by two long bract cells on each side. The central basal cell and these two lateral cells are directly attached to the base of the utricle. The thallus is corticated with cells twisting at an angle of 30°. The utricle of Echinochara pontis displays a combination of features present in Echinochara peckii (Bathonian?–Kimmeridgian) and Echinochara lazarii (Barremian–early Aptian). For instance, the bilateral symmetry of the utricle and the morphology of the inner bract-cell series allow comparison with E. lazarii, whilst the morphology of the outer bract-cell series is closer to E. peckii. Moreover, the thallus of the new species shows cortical cells with a twisting angle intermediate between that of Echinochara peckii (40°–45°) and Echinochara lazarii (not twisted). The unique combination of morphological characters in the utricle of Echinochara pontis fits well with its intermediate chronostratigraphic position between the two former species. Echinochara pontis formed monospecific meadows in brackish settings. A preference for brackish settings is also observed for Echinochara peckii and in the older populations of Echinochara lazarii, suggesting that this habitat is probably a basal character in the evolution of the genus Echinochara.

The First Cretaceous Epyrine Wasp (Hymenoptera: Bethylidae): A New Genus and Species from Early Cenomanian Kachin Amber.

The Epyrinae are the second largest subfamily of Bethylidae and the most diverse in the fossil record. However, although six of the nine bethylid subfamilies are known during the Cretaceous (either as compression or amber fossils), the Epyrinae were hitherto unknown before the lower Eocene. In this contribution, we report the discovery of the oldest member of this group, based on a female specimen from the early Cenomanian amber of Kachin, Myanmar. We describe and illustrate a new genus and species, Hukawngepyris setosus gen. et sp. nov. The new genus is compared with the other epyrine genera and characterized by a unique combination of characters not known in the subfamily. Hukawngepyris setosus gen. et sp. nov. is especially unique in the configuration of the forewing venation, with a complete 2r-rs&Rs vein, curved towards the anterior wing margin, and the presence of three proximal and three distal hamuli. The key to the genera of Epyrinae is accommodated to include the newly erected genus.

New Cretaceous Fossil Achilidae Taxa (Insecta, Hemiptera, Fulgoromorpha) from Burmese Ambers with Description of Niryasaburniini Trib. Nov.

A new species Niryasaburnia nigrutomia sp. nov. of the planthopper family Achilidae from Burmese amber collected from Hukawng Valley (Tanai) of northern Myanmar, is described, notably based on forewing pattern coloration and metatibiotarsal teeth conformation. A new fossil genus with its type species Sinuovenaxius kachinensis gen. et sp. nov. is also described. The tribe Niryasaburniini trib. nov. is established to include Niryasaburnia Szwedo, 2004, and Sinuovenaxius gen. nov., based on a unique combination of characters, of which the following states are particularly notable: head with compound eyes around half the length of pronotum, late forking of ScP+R and CuA after the fusion of Pcu+A1 on the forewing, apical teeth of metatarsomeres I and II both with subapical platellar sensilla, and a unique hindwing pattern with simple RP and biforked MP, CuA with two terminals only, and with A2 simple, reaching the posterior wing margin. The hindwing venation of this new tribe with RP with only one terminal and both MP and CuA with two terminals is unique in Achilidae.

Morphometric and taxonomic approach to describe Heterospio variabilis (Annelida, Longosomatidae), a new species with three size-dependent morphotypes, from the Gulf of California, Eastern Pacific.

The Longosomatidae, a poorly known polychaete family, includes only 23 recognized species; in this study, based on morphometric and taxonomic analyses, we describe a new species with three morphotypes: Heterospio variabilis from the Gulf of California, Mexico. The specimens examined exhibit large morphological variations but were clearly separated from close species due to a unique combination of morphological characters: chaetiger 9 as the first elongated chaetiger, four to eight branchial pairs; chaetae from chaetiger 10 forming rings in two rows, posterior row with thin and robust capillaries, anterior row with subuluncini, aristate spines, acicular spines and thick acicular spines. With the discriminant analysis, carried out on 11 morphometric characters, the presence of three morphological groups were recognized (Wilks' lambda= 0.093, p = 0.0001). However, the variables selected to discriminate the specimens (partial Wilks' lambda >0.57) were correlated to their size: number of branchiae, body width, prostomium width, rate length CH9/CH1-CH8, length CH1-CH8 and length CH9 (r>0.5). So, we concluded that they belong to a single species with three morphotypes: morpho A with eight branchial pairs, morpho B with 5-6-7 pairs and morpho C with 4 pairs. No correlations between the distribution of the distinct morphotypes along the eastern gulf shelf and the environmental conditions where they settle were detected.

Phylogenetic relationships of a new titanosaur (Dinosauria, Sauropoda) from the Upper Cretaceous of Uruguay

The up to 200 m thick Upper Cretaceous deposits of Uruguay includes from base to top the Guichón, Mercedes, and Asencio formations, plus the lateral correlate of the latter, the Queguay Formation. In 2006, the most complete sauropod from the country was excavated from the Guichón Formation near Araújo, Paysandú Department. Augmented by new specimens reported here, the material includes sixty caudal vertebrae (all strongly procoelous, except for the biconvex first one), a partial coracoid, long bone fragments (proximal and distal portions of tibia, proximal portion of fibula), two astragali, and six metatarsals, as well as associated eggshell fragments. The Uruguayan titanosaur shows a unique combination of characters (biconvex first caudal centrum, pneumatic foramina in the anteriormost caudal centra, dorsal tuberosities on the transverse processes of the anterior caudal vertebrae, well developed fibular knob, pyramidal astragalus), as well as a potential autapomorphy – middle caudal centra condyles with hexagonal contour – allowing the proposition of new genus and species, Udelartitan celeste. Phylogenetic analyses were for the first time performed to assess the relations of that taxon, which was recovered either as a saltasaurine saltasaurid or a non-saltasaurid saltasauroid. Further, one of the analyses show Udelartitan celeste nested within a clade including Late Cretaceous titanosaurs with a biconvex first caudal vertebra, such as Alamosaurus sanjuanensis, Baurutitan britoi, and Pellegrinisaurus powelli. This contribution demonstrates that at least two titanosaur lineages were present in the Late Cretaceous of Uruguay: Saltasauroidea and Aeolosaurini, the latter recently recognized in the stratigraphically younger Asencio Formation.

A new ornithopod from the Upper Cretaceous (Huincul Formation) of northwestern Patagonia, Argentina: Implications on elasmarian postcranial anatomy

The aim of the present contribution is to describe the first ornithischian species from the Huincul Formation (Cenomanian-Turonian, Upper Cretaceous) at the Pueblo Blanco Natural Reserve, Río Negro province, Argentina. The new species, named Chakisaurus nekul gen. et sp. nov., can be comfortably included among elasmarian ornithopods. The new species shows humeral anatomy that is congruent with smaller members of the clade (e.g. Anabisetia, Notohypsilophodon), and differs from larger taxa (e.g. Talenkauen, Mahuidacursor) which show humeral features probably related with graviportal habits, such as lack of shaft torsion and a distally located deltopectoral crest. This indicates that graviportal habits were probably acquired independently in elasmarians from other large-sized taxa, such as hadrosauroids. Caudal vertebrae of the new species also show a unique combination of characters shared with other elasmarians, which are absent in previously known ornithopods. These features indicate that some elasmarians had a protonic tail posture, which is unknown in other ornithischians and was previously considered unique to derived titanosaurian sauropods. The shape of transverse processes and neural spines of caudal vertebrae indicate that at least some elasmarians had improved cursorial habilities, that were convergently acquired by selected theropod clades.

New species of Bolbapium Boucomont, 1910 (Coleoptera: Geotrupidae) from Brazil

Bolbapium Boucomont, 1910 is a Neotropical genus of Geotrupidae with 22 known species. In this paper, we describe Bolbapium vazdemelloi sp. nov. in Southwestern Bahia, Brazil. This new species is distinguished from congeneric species by its unique combination of morphological characters: cephalic tubercle adjacent to each eye; pronotum with little expanded bidentate tubercle; parameres symmetric, with acute and divergent apex. The new species was incorporated into a previously published identification key for Bolbapium.

A new dwarf gecko of the genus Pseudogonatodes (Squamata: Sphaerodactylidae) from the eastern slope of the Andean Cordillera de Mrida in northern South America.

Pseudogonatodes is a poorly known genus of small bodied, diurnal, ground-dwelling geckos widely distributed in northern South America. No additional species have been described in over two decades. Herein we describe a new species from the eastern slope of the Cordillera de Mrida in the Venezuelan Andes. The new species is readily diagnosable morphologically from the other seven recognized species of Pseudogonatodes by having a single postnasal scalea putative autapomorphy. Furthermore, it is characterized by a unique combination of phenotypic characters that includes granular dorsal scales, three large postrostrals, five to six loreals, mental U-shaped, four to six postmentals, 2629 ventrals between anterior levels of fore- and hind limbs, third lamella under fourth toe not distinctly enlarged, and subcaudal pattern 11. In addition to characterizing the external morphology, we present a description of the skull, based on 3D digital models reconstructed from high resolution computed microtomography scans. The discovery of this new species highlights the still underestimated diversity of this group of Neotropical dwarf geckos and underscores the need for further studies on its systematics and taxonomy.

Increasing the theropod record of Europe: a new basal spinosaurid from the Enciso Group of the Cameros Basin (La Rioja, Spain). Evolutionary implications and palaeobiodiversity

Abstract A new member of Spinosauridae from the Enciso Group (uppermost Barremian–lower Aptian) from Igea (La Rioja, Spain) is here erected on the basis of axial, pelvic girdle, and hindlimb elements that exhibit a unique combination of characters. Riojavenatrix lacustris gen. et sp. nov. is one of the latest Iberian and European spinosaurid taxa. It retains a triangular pubic boot, like the megalosaurids, and a medial condyle of the femur that shows a transitional stage between the anteroposteriorly oriented long axis of non-spinosaurid theropods and the posteromedially oriented long axis of Spinosauridae. The spinosaurid record of Iberia ranges from the late Hauterivian–early Barremian to the latest Barremian–early Aptian so far, and both the oldest and the most recent evidence comes from the Cameros Basin, where spinosaurid remains are especially abundant in the Barremian deposits. A review of the spinosaurid record has allowed us to dismiss the presence of the genus Baryonyx from Iberia; hence, only Camarillasaurus, Iberospinus, Protathlitis, Riojavenatrix gen. nov., and Vallibonavenatrix are considered to be present in the Early Cretaceous of Iberia. According to this study, Riojavenatrix is one of the youngest baryonychines in the fossil record.

A new clupeoid genus from the Oligocene of Central Paratethys (Menilite Formation, Poland)

The Suborder Clupeoidei Bleeker, 1859 comprises mostly marine fishes, which form large schools feeding on plankton. The fossil record of the suborder in the Late Paleogene reveals that clupeoids were abundant in the Western, Central, as well as Eastern Paratethys. Clupeoid descriptions from the Polish Outer Carpathians (SE Poland, Central Paratethys) remain incomplete due to usage of ‘collective species’, taxonomical inaccuracies, and lack of clear links between extinct and extant representatives. In this paper we present a new clupeoid, † Beksinskiella gen. nov., from the Oligocene of the Outer Carpathians, Poland. The new genus encompasses the nominal species † Maicopiella longimana (Heckel, 1850). † Beksinskiella gen. nov. has a unique combination of characters (skull roof with frontoparietal striae; smooth opercle; 6–7 branchiostegal rays; 42–48 vertebrae; dorsal and anal fins with 21–23 rays; the last two rays of the anal fin being elongated, and the presence of a complete series of abdominal scutes with the postpelvic ones poorly developed), supporting recognition of a new genus of the Suborder Clupeoidei. Similarities and differences between fossil and extant genera of Cluepoidei are discussed to shed light on their relationship.

A new clupeoid genus from the Oligocene of Central Paratethys (Menilite Formation, Poland)

The Suborder Clupeoidei Bleeker, 1859 comprises mostly marine fishes, which form large schools feeding on plankton. The fossil record of the suborder in the Late Paleogene reveals that clupeoids were abundant in the Western, Central, as well as Eastern Paratethys. Clupeoid descriptions from the Polish Outer Carpathians (SE Poland, Central Paratethys) remain incomplete due to usage of ‘collective species’, taxonomical inaccuracies, and lack of clear links between extinct and extant representatives. In this paper we present a new clupeoid, † Beksinskiella gen. nov., from the Oligocene of the Outer Carpathians, Poland. The new genus encompasses the nominal species † Maicopiella longimana (Heckel, 1850). † Beksinskiella gen. nov. has a unique combination of characters (skull roof with frontoparietal striae; smooth opercle; 6–7 branchiostegal rays; 42–48 vertebrae; dorsal and anal fins with 21–23 rays; the last two rays of the anal fin being elongated, and the presence of a complete series of abdominal scutes with the postpelvic ones poorly developed), supporting recognition of a new genus of the Suborder Clupeoidei. Similarities and differences between fossil and extant genera of Cluepoidei are discussed to shed light on their relationship.

Mongolitria: A new Early Cretaceous three-valved seed from Northeast Asia.

Fossil seeds recovered from the Early Cretaceous of Mongolia and Inner Mongolia, China, are described and assigned to Mongolitria gen. nov., a new genus of gymnosperm seed. Abundant lignitized seeds along with compression specimens isolated from the matrix were studied using a combination of scanning electron microscopy, anatomical sectioning, light microscopy, synchrotron radiation X-ray microtomography, and cuticle preparations. A single permineralized seed was examined by light microscopy of cellulose acetate peels and X-ray microtomography. Two species are recognized, Mongolitria friisae sp. nov. and Mongolitria exesum sp. nov. Both seeds are orthotropous with a short apical micropyle and a small, basal, circular attachment scar. The thick sclerenchymatous integument has a consistently three-parted organization and about 20 conspicuous longitudinal ribs on the surface. Mongolitria exesum differs from M. friisae primarily in its much larger size and thicker seed coat, which also preserves clear evidence of insect damage. Mongolitria is similar to other fossil seeds that have been assigned to Cycadales, but displays a unique combination of characters not found in any living or extinct cycadaceous plant, leaving its higher-level systematic affinities uncertain. Germination apparently involved splitting of the integument into three valves. Mongolitria was prominent among the plant parts accumulating in peat swamps in eastern Asia during the Early Cretaceous.

Revision of the Chironius bicarinatus complex (Serpentes: Colubridae): Redefined species boundaries and description of a new species

Abstract Currently, the proposed diagnoses for the Chironius bicarinatus complex reflect a wide variation in color pattern and pholidosis. Herein, we review the Chironius bicarinatus complex based on morphological and molecular data from a sample of 485 specimens covering the species distribution. Our results corroborate the recognition of C. bicarinatus and C. gouveai, and diagnose a distinct lineage without an available name. Thus, here we describe this new species restricted to the Baturité Massif, a relictual rainforest isolated in the Caatinga xerophytic domain, in the state of Ceará, northeastern Brazil. The new species can be distinguished from its congeners by its unique combination of qualitative and quantitative morphological characters (scale counts, morphometric, color pattern), and is also supported by molecular and ecological evidence. Additionally, we rectify data on the distribution and morphological variability of C. gouveai to accurately infer the boundaries between this taxon and C. bicarinatus, which was not properly addressed. Finally, we discuss our results in the light of previous studies that suggest diversification hypotheses in the Atlantic Forest already detected for other taxa, highlighting the importance of conserving the areas of “Brejos de Altitude”, in northeastern Brazil, and the southern limit of Serra do Mar up to Serra do Tabuleiro, in southern Brazil.

Placopsis craterifera (Trapeliaceae, Lecanoromycetes), a new lichen species from alpine habitats on Mount Meru, Tanzania

AbstractDuring a field trip to the highlands of Mount Meru in Tanzania, two Placopsis specimens were collected. Morphological analyses showed a unique combination of characters not observed in any other published taxa within the genus. The specimens are characterized by their circular soralia, not confluent, crater-shaped, with a prominent white margin and coarse granular pinkish central soredia. Considering the morphological, geographical and genetic data, we propose the designation of a new species, Placopsis craterifera Boluda sp. nov.

Isoetes candelariensis, a new species of Isoetaceae (Lycopodiidae) from Argentina.

Isoetes candelariensis is a new species of Isoetaceae from Misiones, Argentina. This species is ephemeral, and grows on basaltic bedrock outcrop pools, in Urutau Reserve from Candelaria Department. This taxon differs from other aquatic Isoetes in this region by the unique combination of characters of its leaves, ligule, labium and megaspore ornamentation.

The last of them? A new relic karaurid stem salamander from the Lower Cretaceous of Western Siberia, Russia

A new karaurid stem salamander, Kuzbassia sola gen. et sp. nov., from the Lower Cretaceous (Aptian) Ilek Formation of Shestakovo 1 locality in Western Siberia, Russia, is described on the basis of isolated vertebrae, including incomplete atlantal and trunk vertebral centra. The new taxon is diagnosed by the following unique combination of vertebral characters: the presence of a shallow dorsolateral depression and low ridges (longitudinal, vertical and oblique ridges) flanking this depression on the lateral surface of the atlantal centrum; the absence of deep lateral grooves or depressions on the lateral surfaces and ventral depression on the ventral surface of the atlantal centrum; the absence of ventro-lateral ridges, transverse processes and alar processes associated with the transverse processes on the atlantal centrum; anterior cotyles with elliptical anterior outline, located at an angle of approximately 150–160 degrees to each other; and the presence of a pair of rugose surfaces with low tubercles (= ?anterior basapophyses) on the ventral surface of the anterior portion of the trunk vertebral centrum. Kuzbassia sola gen. et sp. nov. is the last karaurid salamander in the fossil record to date.

A new annual killifish, Moema beltramonorum (Cyprinodontiformes: Rivulidae) from the Amazon basin, Bolivia.

A new annual killifish species, Moema beltramonorum, is described from a seasonal swamp next to arroyo Crespo, belonging to Ro San Martin, a tributary of Ro Itnez, Amazon River basin, Bolivia. The new taxon presents an unique combination of male colour pattern characters not present in any congener, and an unique caudal fin coloration.

The first articulated skeletons of enigmatic Late Cretaceous billfish-like actinopterygians.

Only few candidates of Mesozoic fishes with a similar body plan and ecological niche to the modern billfishes are suggested as their analogues. Several specimens were recovered from Cenomanian deposits in Germany and Lebanon and display a billfish-like fusiform body with elongated premaxillae. They are found close to the plethodids and show a unique combination of characters (rostrum pointed and extremely elongated, double articular head of the quadrate, anteroposteriorly elongated abdominal centra indicating a slender body and different types of scales on the body) allowing their inclusion in a new genus. Two 'Protosphyraena' species are also assigned to this new genus. This fish can be considered as an ecological analogue to the extant xiphioids sharing their feeding habits. This fish was abundant and roamed, as an apex predator, the Central Tethys and the Boreal realms during the Cenomanian.

A New Miniature Species of Arthroleptis (Anura: Arthroleptidae) from Nyungwe National Park, Rwanda

A new, very small-sized species of Arthroleptis is described from western Rwanda. The new species occurs locally endemic in Nyungwe Forest and Cyamudongo Forest, where it inhabits the leaf litter of montane forests between 1800 and 2200 m a.s.l. It differs from all other members of the genus by a unique combination of morphological characters, including size (SVL of adult males 16.0–16.5 mm), skin texture, length of hindlimbs, and ventral colour pattern; by characteristics of its advertisement call that consists of a single note lasting 17.4 ± 6.4 [11–32] ms and has a dominant frequency of 5861 ± 188 [5531–6029] Hz; and also in the sequence of the 16S rRNA gene that differs from available homologous sequences of other species of the genus by an uncorrected p-distance of at least 4.6%. Details of the natural history as well as two additional call types are described.

Stenotanais (Crustacea, Tanaidacea) from the Santos Basin: the first described species of the family Akanthophoreidae off the Brazilian coast

Benthic samples collected from depths ranging between 686 and 2410 m along the Brazilian continental upper slope from Rio de Janeiro State to Santa Catarina State (23°S to 27°S) yielded a wealth of tanaidacean material, including two new species of Stenotanais. This is the first described species of the family Akanthophoreidae from Brazilian waters. Stenotanais leonardoisp. nov. has a combination of unique characters including the uropod basal article longer than the pleotelson and the exopod somewhat wider than the endopod, longer than the endopod article-1 (0.7 times endopod length) and supporting two flat and wide terminal setae. Stenotanais uropedonsp. nov. is recognisable by its oar-shaped uropod endopod, with article-2 large, broad and flattened and the short exopod, only 0.3 times the endopod length. An identification key to the species of Stenotanais is given. These two species bring the total number of described akanthophoreids to 56 species and that of all tanaidaceans in Brazilian waters to 66 species.