Slender Teeth Research Articles

Molecular phylogeny and new insight into the stomatal complexity of Fictor platypapillata sp. n. (Diplogastridae: Nematoda) associated with Oniticellus cinctus (Coleoptera: Scarabaeidae).

The new species Fictor platypapillata was isolated from dung beetle Oniticellus cinctus (Scarabaeidae), collected from the district Balrampur, Uttar Pradesh, India. Fictor platypapillata sp. n. is described based on morphology, morphometric and molecular characterization, supplemented with scanning electron microscopy observations. The new species is characterized by two female morphs based on stomatal dimorphism: α morph with left subventral wall having 14 denticles, six low conical and eight elongated finger-like, slender denticles separated by a deep groove; inner wall of gymnostom with linearly arranged warts; β morph with inner wall of gymnostom lacking warts; dorsal and right subventral stegostomal walls having large, slender teeth with hook-shaped apical end. Genital sensilla eight pairs with v5 pair flattened, button-shaped, located ventrally. The phylogenetic analyses revealed significant congruence, especially in the position of the subordinate taxa of genus Fictor that shows polyphyly by both Bayesian inference and minimum evolution methods. The taxonomy of the genus is updated with a valid species list along with their geographical mapping.

Signaling Modulation by miRNA-221-3p During Tooth Morphogenesis in Mice.

miRNAs are conserved short non-coding RNAs that play a role in the modulation of various biological pathways during tissue and organ morphogenesis. In this study, the function of miRNA-221-3p in tooth development, through its loss or gain in function was evaluated. A variety of techniques were utilized to evaluate detailed functional roles of miRNA-221-3p during odontogenesis, including in vitro tooth cultivation, renal capsule transplantation, in situ hybridization, real-time PCR, and immunohistochemistry. Two-day in vitro tooth cultivation at E13 identified altered cellular events, including cellular proliferation, apoptosis, adhesion, and cytoskeletal arrangement, with the loss and gain of miRNA-221-3p. qPCR analysis revealed alterations in gene expression of tooth-related signaling molecules, including β-catenin, Bmp2, Bmp4, Fgf4, Ptch1, and Shh, when inhibited with miRNA-221-3p and mimic. Also, the inhibition of miRNA-221-3p demonstrated increased mesenchymal localizations of pSMAD1/5/8, alongside decreased expression patterns of Shh and Fgf4 within inner enamel epithelium (IEE) in E13 + 2 days in vitro cultivated teeth. Moreover, 1-week renal transplantation of in vitro cultivated teeth had smaller tooth size with reduced enamel and dentin matrices, along with increased cellular proliferation and Shh expression along the Hertwig epithelial root sheath (HERS), within the inhibitor group. Similarly, in 3-week renal calcified teeth, the overexpression of miRNA-221-3p did not affect tooth phenotype, while the loss of function resulted in long and slender teeth with short mesiodistal length. This study provides evidence that a suitable level of miRNA-221-3p is required for the modulation of major signaling pathways, including Wnt, Bmp, and Shh, during tooth morphogenesis.

A Hooghly head‐scratcher

A Hooghly head‐scratcher

When destruction comes first: Two new species of Hypostomus Lacépède, 1803 (Siluriformes: Loricariidae) from a deeply‐impacted river in the Rio São Francisco basin in Brazil

Environmental disasters affecting Brazilian rivers have been frequent recently, especially involving mining activities. Two recent dam-rupture events suddenly released millions of cubic meters of iron tailings downstream into two major Brazilian watersheds. These events generated major losses to the environment and human life. Additionally, the biodiversity in both watersheds was still incompletely known. Two new species of the armoured catfish genus Hypostomus were discovered in the Rio Paraopeba and surrounding rivers of the Rio São Francisco Basin. The species share some main characteristics including a depressed body, large dark spots on a clearer background and the absence of keels on flanks. However, while one species (Hypostomus freirei sp. n.) has a large mandibular ramus and numerous slender teeth, the other (Hypostomus guajupia sp. n.) has a shorter mandibular ramus and few robust teeth. The discovery of these two new mid-sized fish species emphasizes the presumption that the effects of major environmental disasters cannot be fully estimated as local biodiversity is not completely known. This discovery in a recently devastated area also shows that tough environmental laws for the protection, supervision and mitigation of major impacts are urgently needed in developing countries.

A new longirostrine sperm whale (Cetacea, Physeteroidea) from the lower Miocene of the Pisco Basin (southern coast of Peru)

The modern sperm whales Kogia and Physeter (superfamily Physeteroidea) represent highly disparate, relict members of a group of odontocetes that peaked in diversity during the middle to late Miocene. Based on a highly informative specimen (including the cranium with ear bones, mandibles, teeth and some postcranial elements) from the lower Miocene (early Burdigalian, 19–18 Ma) of the Chilcatay Formation (Pisco Basin, Peru), we describe here a new genus and species of physeteroid, Rhaphicetus valenciae gen. et sp. nov. The latter is one of the geologically oldest physeteroids. This medium-sized species (estimated body length between 4.7 and 5.7 m) differs from all other physeteroids by the following, probably autapomorphic, features: a narrow, cylindrical rostrum comprising nearly 75% of the condylobasal length; the two main dorsal infraorbital foramina located posterior to the antorbital notch; an upper tooth count of at least 36 teeth per quadrant; and anterior-most upper alveoli filled by thick bony pads. Our phylogenetic analysis recovers R. valenciae as one of the earliest branching stem physeteroids. The highly unusual filling of the anterior upper alveoli by bony pads is interpreted as part of a mechanism leading to the loss of apical and subapical upper teeth. By comparison with other odontocetes displaying some degree of anterior reduction of the dentition, this condition may have corresponded to the rostrum being anteriorly longer than the mandible. The elongated rostrum with a circular cross-section, the long temporal fossa, and the high number of slender, pointed upper and lower teeth all suggest that R. valenciae used its dentition to grasp relatively small prey, possibly via rapid movements of the head. On the one hand, this new Peruvian record increases our knowledge of the morphological disparity of sperm whales during the Miocene. On the other hand, it may provide clues to the ancestral morphotype for all physeteroids. http://zoobank.org/urn:lsid:zoobank.org:pub:3E1CEFC8-0F23-416E-9C02-03750D7199BA

Rediscovery and redescription of the endangered Hypostomus subcarinatus Castelnau, 1855 (Siluriformes: Loricariidae) from the Rio São Francisco basin in Brazil.

Hypostomus subcarinatus Castelnau, 1855 is rediscovered in the Lagoa da Pampulha, an urban lake in the Rio das Velhas basin (Rio São Francisco system) in the state of Minas Gerais, southeastern Brazil. Herein, H. subcarinatus is redescribed and diagnosed from its congeners based on characters such as blue-tan dorsal fin in live specimens, slender bicuspid teeth, dentaries angled more than 90 degrees, moderate keels along lateral series of plates, small roundish dark spots, one plate bordering supraoccipital, by having nuptial odontodes mainly on pectoral, dorsal and caudal-fin rays, and long anal-fin unbranched ray. The rediscovery of H. subcarinatus more than 160 years after its original description was an unexpected event, because the Lagoa da Pampulha is an artificial, silted and polluted urban lake. The lake is located in downtown Belo Horizonte, the third largest urban agglomeration in Brazil with a population exceeding 5.9 million inhabitants.

Ranunculus kobendzae, a New Species of the R. auricomus Complex (Ranunculaceae) from Poland

Ranunculus kobendzae Halamski sp. nova (Ranunculaceae) is a representative of the partly apomictic R. auricomus complex and is characterised by undivided, reniform radical leaves with a very wide basal angle, segments of stem leaves with partly slender teeth, mostly imperfect flowers, and pilose, ovate to cylindrical tori (receptacles) with a marked intervallum. Similar microspecies of the R. auricomus complex are R. uplandicus, R. allemannii, R. ganeschinii, R. neumannii, R. zmudae and R. mendosus, but the combination of characters of radical and stem leaves of R. kobendzae is unique. At the type locality in Lipka (Debina) near Warszawa (Warsaw, capital of Poland), R. kobendzae grows in an oak–hornbeam forest, and in three other locations in central Poland (Puszcza Slupecka, Branszczyk and Blogie) in hornbeam or alder forests. The DNA ploidy level was determined by propidium iodide flow cytometry from a dried herbarium specimen and was found to be tetraploid (2n = 4x).

Four new deepwater Ophichthus (Anguilliformes: Ophichthidae) from Japan with a redescription of Ophichthus pallens (Richardson 1848)

In this paper, new and uncertain Japanese snake eels of the genus Ophichthus are treated. Ophichthus kusanagi, O. lupus, O. oligosteus and O. yamakawai are herein described as new species. Ophichthus kusanagi, collected from Suruga Bay of Shizuoka Prefecture, off Owase, Mie Prefecture, and Tosa Bay, Kochi Prefecture, is distinguishable from four similar congeners by having one + four supraorbital and two preopercular pores, 13 pectoral-fin rays, fewer total vertebrae (158–163), a longer tail [58–60% of total length (TL)], a small eye [7.5–9.0% of head length (HL)], an acute snout, a low knob on upper lip between nostrils, relatively slender teeth, and a pointed pectoral fin. Ophichthus lupus, collected from the East China Sea, is characterized by its numerous total vertebrae (180–182), shorter pectoral fins (20–25% HL), and the position of the dorsal-fin origin (slightly behind the pectoral-fin tip); it can be distinguished from similar species in its supraorbital and mandibular pores (one + four and six or seven), arrangements of teeth on its mandible and vomer (almost uniserial), its robust body (depth 2.6–3.1% TL), slightly larger head (7.8–8.1% TL), longer and acute snout (24% HL), longer upper jaw (45–48% HL), absence of protrusion along upper lip, and the narrow dark margin of its dorsal fin. Ophichthus oligosteus, collected from Tosa Bay of Kochi Prefecture, is characterized by its fewer preanal and total vertebrae (46 and 121). Ophichthus yamakawai, collected from Kochi Prefecture, is characterized by its large blotches along the lateral line and numerous preanal and total vertebrae (67 and 172). We refer an uncertain species, Ophichthus stenopterus Cope 1871, to the synonymy of Ophichthus pallens (Richardson 1848), a forgotten species described from China. Pisoodonophis zophistius Jordan and Snyder 1901 is recognized as valid in Ophichthus and a senior synonym of Ophichthys intermedius Regan 1905. Ophichthus habereri Franz 1910, originally described from Yokohama, central Japan, is a junior synonym of Ophichthus asakusae Jordan and Snyder 1901. Pisodonophis sangjuensis Ji and Kim 2011 is referred to Ophichthus. We currently recognize 20 species of Ophichthus from Japan. A key to the Japanese species of Ophichthus and its closely associated group Pisodonophis is provided.

Determining the gingival biotype based on dentopapillary compound

Introduction: Knowledge of the gingival biotype or phenotype is of fundamental importance to an oral clinician. There is a direct correlation between gingival biotype and susceptibility to gingival recession following surgical and restorative procedures. The thick and slightly scalloped marginal gingiva with short and wide teeth on the one hand and the thin and highly scalloped marginal gingiva with slender teeth on the other may be the reason for different periodontal entities or so-called “gingival biotypes.” Aim: The present study is to analyze gingival biotype based on dentopapillary complex, taking transparency of the periodontal probe through the gingival margin as a method to differentiate thin from thick gingiva in different age groups. Materials and Methods: Sixty periodontally healthy individuals with all anterior teeth in both the jaws were participated in this study. Results: Thick biotype had area of anterior crowns as 490.17 mm2. Thin biotype had area of anterior crowns as 420.14 mm2 with P = 0.00 having high clinical significance. Conclusion: Teeth with large dentopapillary area had thick gingival biotype. Taking into consideration that the shape, size, form of the tooth and the surrounding gingiva is of paramount importance for the causation and progression of disease.

Hypostomus velhochico, a new keeled Hypostomus Lacépède, 1803 (Siluriformes: Loricariidae) from the rio São Francisco basin in Brazil.

Hypostomus velhochico sp. n., is described from the rio São Francisco basin, in the states of Minas Gerais and Bahia, Brazil. The new species is mainly distinguished from its congeners by a combination of characters such as slender bicuspid teeth, dentaries angled more than 90 degrees, conspicuous keels along lateral series of plates, small roundish dark spots, one plate bordering supraoccipital, spots aligned along lateral series of plates, and by attaining small to medium size. Hypostomus velhochico is widespread in the rio São Francisco basin and has a more similar general pattern of external morphology to species from the Northeastern Brazilian Coastal drainages than to species of the rio São Francisco basin. Aspects about its ecology and its putative relationship are discussed.

A new species of Pontonema (Oncholaimidae, Nematoda) and a redescription of Pontonema incisum Wieser, 1953 from Santa Cruz and Chubut Provinces, Argentina.

Pontonema golfonuevensis sp. nov. from Chubut Province, Argentina is described and a description of the male of Pontonema incisum Wieser, 1953 from Chubut and Santa Cruz Provinces is provided. Pontonema golfonuevensis sp. nov. is characterized by having the slender sub-ventral teeth 25 µm long located at 24 % of stoma length, a short, broad dorsal tooth at 60 % of stoma length, excretory pore opening at level of base of the buccal cavity, and by having a ventral precloacal sensory field with four papillae and a glandular sub-ventral area with seven papilliform sensillae. The male of P. incisum has long slender sub-ventral teeth at 36 % of stoma length, a short broad dorsal tooth at 72 % of stoma length, excretory pore about two buccal cavity lengths from the anterior end, and a ventral precloacal sensory field without papillae and a glandular sub-ventral area with twelve to fourteen papilliform sensillae. A key for identification of males of Pontonema is presented.

Tracing functional adaptation in African cichlid fishes through morphometric analysis of fossil teeth: exploring the methods

The sedimentary archive of Crater Lake Challa in East Africa contains abundant fossil teeth of cichlid fishes throughout at least the last 25,000 years. Here, we use morphometric analyses of oral teeth from the two extant Oreochromis species inhabiting Lake Challa to explore the feasibility of tracing adaptive modification of the cichlid trophic apparatus in the lake’s fossil record. We compared the performance of semi-landmark analysis (SLM) and elliptic Fourier analysis in capturing morphological variation in oral tooth crowns, and found that SLM, supplemented with tooth shaft measurements, ensured consistency with whole-body landmark analyses. Whole-body and tooth morphology data both allowed to discern between the indigenous Oreochromis hunteri and the recently introduced Oreochromis korogwe. Both species have an oral jaw arrangement of outer-row bicuspid and inner-rows tricuspid teeth, but O. hunteri has generally more slender teeth with a proportionally taller major cusp than O. korogwe, suggesting fine-scaled resource partitioning. Exploratory analysis of three fossil samples showed that the major tooth types of modern-day Oreochromis are also represented in the fossil record. Their total morphological variation is largely restricted to the morphospace occupied by contemporary teeth, suggesting a close functional relationship between ancient populations and their likely descendant, O. hunteri.

Evaluation of the thickness of facial anterior gingiva and posterior palatal mucosa by transgingival probing

The gingival morphology of the maxillary anterior region plays an important role in determining the final aesthetic outcome as it is associated with the outcomes of periodontal therapy, root coverage procedures and implant esthetics.1 Biotype defined as part of body having the same genotype. The identification of the gingival biotype may be important in clinical practice since difference in gingival and osseous architecture have been shown to exhibit a significant impact on the outcome of restorative therapy.2 The stability of the osseous crest and soft tissue is directly proportional to the thickness of the bone and gingival tissue. The term gingival or periodontal phenotype has recently been coined by Seibert and Lindhe3 to address a common clinical observation of great variation in thickness and width of facial keratinized tissue and they categorized the gingiva into thick and thin. The thick gingiva is characterized as bulky, slightly scalloped gingival margins with short wide teeth and the thin gingiva is characterized by highly scalloped gingival margins with slender teeth.2,3 Claffey and Shanley4 defined that the gingival tissue biotype is thin if gingival thickness is <1.5 mm and thick if its thickness is = 2 mm. It is a widely accepted clinical impression that a thin, highly-scalloped gingiva tends to recede from source of irritation (artificial crown margin or microbial irritants) and gingival recession often occurs following traumatic or surgical injury.

Taxonomic revision of SpectracanthicusNijssen &amp; Isbrücker (Loricariidae: Hypostominae: Ancistrini), with description of three new species

A taxonomic review of Spectracanthicus Nijssen &amp; Isbrücker, including Oligancistrus Rapp Py-Daniel, following a phylogenetic study, is presented. Additionally to S. punctatissimus(Steindachner) and S. murinus Nijssen &amp; Isbrücker, three new species are recognized based on the examination of 159 specimens: S. immaculatus n. sp. from rio Tapajós basin, differs from its congeners by its color pattern consisting of a dark gray body, with no dots or spots, and by having very slender teeth; Spectracanthicus tocantinensisn. sp., from the rio Tocantins drainage is distinguished by the color pattern consisting of dark brown or black body with small, yellowish dots (except in S. punctatissimus), presence of thick teeth, infraorbital 4 forming most of the posterior edge of the orbit and the large basipterigium fenestrae; and Spectracanthicus zuanonin. sp., from the rio Xingu basin is diagnosed by its color pattern consisting of large, white spots and by the larger orbital diameter. Other characters based on osteological features are also usefull to distinguish the species. A key to the species of the genus and a brief discussion of their threats and conservation are also provided.

Seladonia (Pachyceble) henanensis sp. n. (Hymenoptera, Halictidae) from China

Seladonia (Pachyceble) henanensis sp. n., is described from Henan Province, the eastern-central part of China. This species is separated from its allied species by a combination of the following morphological characters: head broad in female, inner hind tibial spur of female with 7–8 slender teeth, T1 basolaterally with appressed hair tuft in both sexes, and genitalia with long and large lower gonostylus in male. Important taxonomic characters are illustrated with photographs, scanning electron micrographs, and line drawings.

Acanthodian Jaw Bones from Lower Devonian Marine Deposits of Podolia, Ukraine

Ischnacanthiform acanthodian dentigerous jaw bones from the Lower Devonian (Late Lochkovian) of Podolia are described for the first time. One new genus and one new species are established. Podoliacanthus gen. nov. is diagnosed as having small-sized jaw bones, the presence of specific accessory cusps/denticles on the medial side of teeth of the lateral tooth row, and groups of denticles forming the lingual tooth row. Podoliacanthus zychi sp. nov. is distinguished in having elongated slender jaw bones and lateral teeth with one medial side denticle. Besides, three species are described in open nomenclature: Podoliacanthus sp. 1, while similar to Podoliacanthus zychi sp. nov., differs in having stronger posterior inclination of the teeth tips and presence of well developed flanges of the teeth, P. sp. 2 has quite robust jaw bones and teeth with two medial side denticles, and Podoliacanthus sp. 3 has small narrow jaw bones and teeth with three medial side denticles. Morphology of the lingual tooth row is cons...

A ctenochasmatid pterosaur from the Stonesfield Slate (Bathonian, Middle Jurassic) of Oxfordshire, England

Abstract The anterior end of a lower jaw bearing long slender teeth, from the Bathonian Stonesfield Slate of Oxfordshire, was hitherto referred to the crocodilian Teleosaurus. It is reinterpreted as belonging to a ctenochasmatid pterosaur reminiscent of Gnathosaurus. It is the earliest known representative of the Ctenochasmatidae, and one of the earliest known pterodactyloids. The diversity of pterosaurs from the Stonesfield Slate is higher than previously recognized, comprising at least three taxa.

A re-examination of Hauffiosaurus zanoni, a pliosauroid from the Toarcian (Early Jurassic) of Germany

ABSTRACT The holotype and only known specimen of the pliosauroid plesiosaur Hauffiosaurus zanoni O’Keefe is a substantially complete and almost entirely articulated skeleton from the Toarcian Posidonien-Schiefer (Upper Lias, Lower Jurassic) of Holzmaden (Baden-Württemberg), Germany. The original description of this specimen was preliminary, and this paper presents a detailed re-description and revised diagnosis of the specimen, thus adding significant, new anatomical information. Characters such as the presence of a lateral palatal fenestra and the absence of a contact between the internal nares and the palatines are examples of phylogenetically relevant characters. The specimen presents a novel and unique combination of characters and body proportions, including a long ilium, short ischia, and propodials longer than any of their associated girdle bones, that separate it from all other pliosauroid taxa. Its elongate snout and long, slender teeth imply that this species most likely had a prey preference of fish.

A new species of worm salamander (Caudata: Plethodontidae: Oedipina) in the subgenus Oeditriton from the highlands of northern Nicaragua

We describe a new species of Oedipina (subgenus Oeditriton) from the highlands of north-central Nicaragua. The new species is most closely related to Oedipina kasios, a premontane species from north-central Honduras, and O. quadra, a lowland species from northern and eastern Honduras. It differs from O. kasios and O. quadra in molecular characters and by having a more slender habitus and fewer vomerine teeth. We also discuss the status of the additional populations of Oedipina from Nicaragua.

Dental Morphologies in Gartersnakes (Thamnophis) and Their Connection to Dietary Preferences

We examined morphological variation in tooth structure in four populations of garter snakes (genus Thamnophis) with diverse feeding habits and tested the hypothesis that morphological homoplasy evolved in the malacophagous predators Thamnophis ordinoides and Thamnophis elegans terrestris. Although long, slender teeth are typical in Neotropical colubrid snake species that prey on slugs and snails, this morphological feature did not occur in T. ordinoides and T. e. terrestris relative to closely related garter snakes (the diet generalist Thamnophis elegans elegans and piscivore Thamnophis couchii). However, we did find pronounced posterior ridges located on the posterior maxillary teeth in the two slug predators but not in the generalist feeders. The evolutionary origin and functional advantage of these ridges has yet to be identified. The fish specialist T. couchii has many morphological features characteristic of adaptations for piscivory, such as long, sharper teeth and elongated mandible bones.