Small Hooks Research Articles

Extraction of trapped double J in ureteroscope: a novel technique.

Urological endoscopes and percutaneous devices are expensive and their maintenance and cleaning need special attention. Sometimes urologists can help repairing their devices. During taking out a Double J, Double J was trapped in the working channel of ureteroscope unintentionally. It was not possible to take it out by pushing methods. Finally, Double J was pulled out by a changed nephrostomy needle to a small curve hook. Using the hand-made hook to pull out a trapped Double J from ureteroscope does not destroy the device.

First parasitological, histopathological and molecular characterization of Echinococcus vogeli Rausch and Bernstein, 1972 from Cuniculus paca Linnaeus, 1766 in the Cerrado biome (Mato Grosso do Sul, Brazil)

Polycystic echinococcosis (PE) is caused by Echinococcus vogeli metacestodes (larval stage) in Neotropical countries. E. vogeli is trophically-transmitted between predators bush dogs (Speothos venaticus) and prey pacas (Cuniculus paca). In Brazil, reported PE cases are restricted to the Amazon biome. In this study, metacestodes from a paca hunted in Mato Grosso do Sul state (Cerrado biome) were identified morphological and histopathological techniques and further confirmed by molecular testing (sequencing of cytochrome C oxidase subunit I (cox1) gene) for the first time. Images of the whole liver showed superficial bubble-like hepatic masses. The parasitological analysis revealed large hooks (41.3 ± 1.2 μm length/12.8 ± 0.8 μm width) and small hooks (33.0 ± 1.5 μm length/11.1 ± 1.2 μm width), consistent with E. vogeli. Microscopically, the liver showed protoscoleces, a thick laminated layer, fibrosis, and inflammatory infiltrate in the adventitial layer. The DNA sequencing confirmed E. vogeli with 99% homology with sequences deposited in the GenBank. In addition, this finding greatly extends the geographic range of animal polycystic echinococcosis into the Cerrado. It is likely to occur in new biomes, where bush dogs and pacas share a given area in a trophic relationship.

Microhook ab interno trabeculotomy, a novel minimally invasive glaucoma surgery.

Trabeculotomy (LOT) is performed to reduce the intraocular pressure in patients with glaucoma, both in children and adults. It relieves the resistance to aqueous flow by cleaving the trabecular meshwork and the inner walls of Schlemm’s canal. Microhook ab interno LOT (µLOT), a novel minimally invasive glaucoma surgery, incises trabecular meshwork using small hooks that are inserted through corneal side ports. An initial case series reported that both µLOT alone and combination of µLOT and cataract surgery normalize the intraocular pressure during the early postoperative period in Japanese patients with glaucoma. Microhook can incise the inner wall of Schlemm’s canal without damaging its outer wall easier than the regular straight knife that is used during goniotomy. Advantages of µLOT include: a wider extent of LOT (two-thirds of the circumference), a simpler surgical technique, being less invasiveness to the ocular surface, a shorter surgical time than traditional ab externo LOT, and no requirement for expensive devices. In this paper, the surgical technique of µLOT and tips of the technique are introduced.

Friction stir weld-bonding defect inspection using phased array ultrasonic testing

Weight reduction is an important driver of the aerospace industry, which encourages the development of lightweight joining techniques to substitute rivet joints. Friction stir welding (FSW) is a solid-state process that enables the production of lighter joints with a small performance reduction compared to the base material properties. Increasing the FSW lap joint performance is an important concern. Friction stir weld bonding is a hybrid joining technology that combines FSW and adhesive bonding in order to increase the mechanical properties of FSW lap joints. FSW and hybrid lap joints were produced, using 2-mm-thick AA6082-T6 plates and a 0.2-mm-thick adhesive layer. Defect detection using the non-destructive test, phased array ultrasonic testing (PAUT), has been made. Microscopic observations were performed in order to validate the phased array ultrasonic testing results. Lap shear strength tests were carried out to quantify the joint’s quality. PAUT inspection successfully detected non-welded specimens but was not able to distinguish specimens with major hook defects from specimens correctly weld bonded with small hook defects.

Grasping the shape of belemnoid arm hooks—a quantitative approach

AbstractChitinous arm hooks (onychites) of belemnoid coleoid cephalopods are widely distributed in Mesozoic sediments. Due to their relative abundance and variable morphology compared with the single, bullet-shaped, belemnite rostrum, arm hooks came into the focus of micropaleontologists as a promising index fossil group for the Jurassic–Cretaceous rock record and have been the target of functional, ecological, and phylogenetic interpretations in the past. Based on three well-preserved arm crowns of the Toarcian diplobelidChondroteuthis wunnenbergi, we analyzed the shape of a total of 87 micro-hooks. The arm crown ofChondroteuthisis unique in having uniserial rather than biserial hooks. The first application of elliptic Fourier shape analysis to the arm weapons of belemnoid coleoids allows for the distinction of four micro-hook morphotypes and the quantification of shape variation within these morphotypes. Based on the best-preserved arm crown, we reconstructed the distribution of morphotypes within the arm crown and along a single arm. Our quantitative data support former observations that smaller hooks were found close to the mouth and at the most distal arm parts, while the largest hooks were found in the central part of the arm crown. Furthermore, we found a distinct arm differentiation, as not every arm was equipped with the same hook morphotype. Here, we report the functional specialization of the belemnoid arm crown for the first time and speculate about the potential function of the four morphotypes based on comparisons with modern cephalopods. Our analyses suggest a highly adapted functional morphology and intra-individual distribution of belemnoid hooks serving distinct purposes mainly during prey capture.

Reducing the Hook Defect of Friction Stir Lap Welded Ti-6Al-4V Alloy by Slightly Penetrating into the Lower Sheet

For the purpose of reducing the hook defect in friction stir lap welding joint, Ti-6Al-4V alloy was lap welded by slightly penetrating into the lower sheet. Hook feature, microstructure and mechanical properties of the lap joints were mainly discussed. Results show that using slight penetration, plastic material mainly concentrates above the lap interface, which is beneficial to suppress the primary hook and broaden the stir zone (SZ) width. Simultaneously, a very small secondary hook is formed. The void-like defect, which is formed due to high peak temperature and big temperature gradient along thickness, can be eliminated by decreasing the rotating speed. Microstructures along thickness show much difference due to big temperature gradient. SZ hardness of both the upper and lower sheets is higher than the base material due to finer grains. Bigger lap shear failure load can be obtained using 150 rpm, which is 17.1 KN. Lap joints fracture along the secondary hook and present ductile fracture mode.

Morphology and taxonomy of three new marine sand-dwelling Amphidiniopsis species (Peridiniales, Dinophyceae) from the Sea of Japan, Russia

:Three new thecate, heterotrophic sand-dwelling marine dinoflagellates of the genus Amphidiniopsis were collected in sublittoral sand of Peter the Great Bay of the Sea of Japan. The cell morphology was examined by light and scanning electron microscopy. All three species were dorsoventrally flattened and had three anterior intercalary plates. Amphidiniopsis ovalis sp. nov. was oval, 27.0–43.5 μm long and 24.0–38.1 μm wide. The length to width ratio was 1.1–1.2. The plate formula was apical pore complex (APC) 4′ 3a 7″ 3c 4(5)s 5′″ 2″″. The first apical plate was not in contact with the APC. The cingulum was slightly ascending less than half a cingular width. The sulcus was characteristically curved and slightly shifted to the left side of the cell. The theca was smooth or slightly reticulated. Amphidiniopsis elongata sp. nov. was almost rectangular, with a small apical hook and rounded posterior end, 42.0–64.0 μm long and 28.0–42.0 μm wide. The length to width ratio was 1.3–1.7. The cingulum was ascending about four cingular widths. The sulcus was characteristically curved and markedly shifted to the left cell side. The plate formula was APC 4′ 3a 6″ 5c 4(6)s 5′″ 2″″. The theca was smooth with large and small pores. Amphidiniopsis hoppenrathae sp. nov. was rounded with a small apical hook, 39.2–48.9 μm long and 35.4–42.8 μm wide. The length to width ratio was 1.1. The plate formula was APC 4′ 3a 6″ 3c 4s 5′″ 2″. The first apical plate was not in contact with the sulcus, and three anterior intercalary plates were located on the ventral side. The cingulum ascended about two cingular widths. The sulcus was located in the middle of the ventral side of the cell. The theca was ornamented with short spines.

Clavicle Hook Depth and Impingement Syndrome—A Cause-Effect Relationship

Background: Clavicular hook plates are effective fixation devices for lateral end clavicle fractures and acromioclavicular joint dislocations and have been extensively used in the last decade. Although this plate achieves a high percentage of union, there are concerns about sub-acromial osteolysis and impingement of supraspinatus tendon. Objective: To show that impingement of supraspinatus tendon can be prevented by measuring the depth between acromion and supraspinatus tendon posteriorly and using hook plates of appropriate depth. Materials and Methods: We performed a prospective study on 25 patients with lateral end clavicle fractures and acromio clavicular joint disruptions by measuring the depth between posterior border of acromion and the superior border of supraspinatus at the point of application of hook plate. Fixation is then done by appropriate sized hook plate. Results: None of the patients had impingement of supraspinatus tendon. Five patients developed subacromial osteolysis which did not have any impact on shoulder function. Conclusion: There is a variation in anatomy of the acromion in different ethnic groups. Hence uniform sized hook plate will be inappropriate. A smaller hook depth is needed in south Asian population to prevent impingement.

A New Species of Centrohelid Heliozoan Acanthocystis amura n. sp. Isolated From Two Remote Locations in Russia.

A new species of centrohelid heliozoan Acanthocystisamura from the Amur River, the Far East of Russia was studied with light- and electron microscopy. Acanthocystis amura has simple oval plate scales (1.2-2.6×1.0-1.8μm) with an axial thickening and a thin border as well as two types of spine scales. The spine scales of type1 were 1.3-4.8μm long and had four small hooks on their tips. The spine scales of type2were shorter, 1.0-3.6μm long and had four teeth at the distal end. The morphology of A.amura resembles that of Acanthocystisquadrifurca. They both have similar spine scales but their plate scales are completely different. Acanthocystisvaldiviense differs from the new species in absence of hook-bearing scales. Molecular phylogeny based on 18SrDNA consistently placed A.amura into Acanthocystis nichollsi/Acanthocystis costata clade, but relationships between those three species were not resolved. Morphology of another centrohelid strain from another location (the South Urals) has been compared with that of the original strain and few minor differences in size characteristics of the scales have been revealed.

Cerebral and non-cerebral coenurosis: on the genotypic and phenotypic diversity of Taenia multiceps.

We characterised the causative agents of cerebral and non-cerebral coenurosis in livestock by determining the mitochondrial genotypes and morphological phenotypes of 52 Taenia multiceps isolates from a wide geographical range in Europe, Africa, and western Asia. Three studies were conducted: (1) a morphological comparison of the rostellar hooks of cerebral and non-cerebral cysts of sheep and goats, (2) a morphological comparison of adult worms experimentally produced in dogs, and (3) a molecular analysis of three partial mitochondrial genes (nad1, cox1, and 12S rRNA) of the same isolates. No significant morphological or genetic differences were associated with the species of the intermediate host. Adult parasites originating from cerebral and non-cerebral cysts differed morphologically, e.g. the shape of the small hooks and the distribution of the testes in the mature proglottids. The phylogenetic analysis of the mitochondrial haplotypes produced three distinct clusters: one cluster including both cerebral isolates from Greece and non-cerebral isolates from tropical and subtropical countries, and two clusters including cerebral isolates from Greece. The majority of the non-cerebral specimens clustered together but did not form a monophyletic group. No monophyletic groups were observed based on geography, although specimens from the same region tended to cluster. The clustering indicates high intraspecific diversity. The phylogenetic analysis suggests that all variants of T. multiceps can cause cerebral coenurosis in sheep (which may be the ancestral phenotype), and some variants, predominantly from one genetic cluster, acquired the additional capacity to produce non-cerebral forms in goats and more rarely in sheep.

Distal Radius Fractures—Lunate facet

Introduction: Fractures of the radius distal to the watershed line show a significant risk factor for secondary dislocation especially when the lunate fossa is involved. These fracture patterns act as avulsion of the attachments of the strong radiocarpal ligaments and destabilize the carpus. If no proper fixation is done, the carpus pushes the fragments volarly leading to dislocation and carpal subluxation. Materials and Methods: Conventional plates usually cannot provide stable fixation. Depending on the size of the fragments, which is best analyzed by computed tomographic (CT) scan, decision making for fixation technique is done. In case of larger fragments, polyaxial plates preferably with the watershed design might be sufficient. New plates sparing the area of the flexor pollicis longus (FPL) tendon offer the advantage to mount the plate far distal without the risk for tendon irritation. However, when the fragments are very small, additionally fragment-specific devices are necessary. One option is small hook plates fixed with tiny self-drilling and self-cutting screws, which produce higher stability as K-wires. Nevertheless, after fixation, radiocarpal stability should be checked under x-ray control. If there are signs of instability, additionally temporary K-wire fixation dorsally through the radius into the lunate prevents carpal subluxation. Results: Analysis of 10 clinical cases demonstrates that when these guidelines are followed, risk for secondary dislocation can be significantly reduced, and vice versa if not frequently secondary dislocation occurs. Conclusion: The problem of the troublesome lunate facet should be recognized and needs adequate treatment. Secondary dislocation frequently causes fixed radiocarpal subluxation and arthritic changes with the need for salvage procedures like radio-scapho-lunate (RSL) fusion.

Synergistic and interactive effects of angler behaviour, gear type, and fish behaviour on hooking depth in passively angled fish

Despite a growing body of literature on the impacts of recreational fisheries on wild populations, surprisingly little is known regarding how individual differences in fish behaviour and their interaction with a baited hook influences hooking injury. We used an underwater video camera, fixed to the fishing line, to record the behaviour of wild sunfishes (Lepomis spp.) as they approached and attacked one of four treatments of baited hook used under a passive angling scenario. Angler reaction time was measured as the difference between the fish strike and hook set. Length-corrected hooking depth was evaluated as a function of multiple putative explanatory variables. Angler performance (hooksets/min) varied over the two day study, where hooksets/min decreased with small hooks and increased with large hooks. Model selection and model averaging revealed the top models included the terms: angler reaction time, approach to bait (cautious, deliberate, aggressive), hook size (small or large), and the interaction between approach to bait and hook size. The model-averaged fitted values indicated that length-corrected hooking depth increased most dramatically with angler reaction time when fish aggressively attacked a baited hook. A cautious approach to a large baited hook led to a deeper length-corrected hooking depth than a similar approach to a small baited hook. These results illustrate synergistic and interactive relationships among factors known to influence impairment, injury, and mortality in caught and released fish. Of particular novelty was our ability to assess the variation in how fish behaviour influences injury in a catch-and-release fishery using underwater cameras, which suggests that this approach holds promise in fisheries science.

Morphology and genetic variability within Taenia multiceps in ruminants from Italy

The aim of this study was to investigate the genetic variability and population structure of Taenia multiceps, and to correlate morphological features of individual coenuri with haplotypes. A total of 92 animals (86 sheep; 4 goats; 1 cattle; 1 mouflon, Ovis musimon) aged between 6–36 months showing clinical symptoms of cerebral coenurosis were included in this study. T. multiceps coenuri (n=118) sampled from live animals during routine surgery procedures or at post-mortem inspections were examined morphologically and molecularly identified. Morphological features of the 52 coenuri selected for this study (number and size of large and small hooks) were within the range reported in the literature. Fifty-two of the molecularly confirmed T. multiceps coenuri harboured by 47 animals (sheep=41; cattle=1; goats=4; mouflon=1) were used to determine gene genealogies and population genetic indices and were compared to the 3 T. multiceps genetic variants, Tm1–Tm3 previously described from Sardinia, Italy. For the 379 bp cox1 dataset we identified 11 polymorphic sites of which 8 were parsimony informative. A high haplotype diversity (0.664±0.067) was recorded for the cox1 sequences defining 10 haplotypes (TM01–TM10). The comparison of haplotypes generated in this study with published T. multiceps Tm1 variant pointed to the possible existence of a common lineage for T. multiceps. No correlation was detected between the size of the small and large hooks and the cox 1 haplotypes. Polycystic infestation (2–9 coenuri) was recorded in 27.7% of animals (13/47). No statistical correlation between polycystic T. multiceps infection and haplotypes was detected.

Morphological and molecular descriptions of Moniliformis saudi sp. n. (Acanthocephala: Moniliformidae) from the desert hedgehog, Paraechinus aethiopicus (Ehrenberg) in Saudi Arabia, with a key to species and notes on histopathology

A new acanthocepohalan species, Moniliformis saudi sp. n. is described from the desert hedgehog, Paraechinus aethiopicus (Ehrenberg), in central Saudi Arabia. Fourteen other valid species of Moniliformis Travassos, 1915 are recognised. The new species of Moniliformis is distinguished by having a small proboscis (315-520 µm long and 130-208 µm wide) with two apical pores, 14 rows of 8 hooks each and small hooks, thre largest being 25-31 µm long anteriorly. Distinguishing features are incorporated in a dichotomous key to the species of Moniliformis. The description is augmented by scanning electron microscopical (SEM) observation and DNA analysis of nuclear (18S rRNA) and mitochondrial (cytochrome oxidase subunit 1; cox1) gene sequences. Attached worms cause extensive damage to the immediate area of attachment in the host intestine. This includes tissue necrosis and blood loss due to damage to capillary beds. Worms also obstruct essential absorbing surfaces.

Ultrastructural observations of the attachment organs of the monogenean Rajonchocotyle emarginata (Olsson, 1876) (Polyopisthocotylea: Hexabothriidae), a gill parasite of rays.

The present study uses scanning and transmission electron microscopical observations to examine the haptoral features of the hexabothriid polyopisthocotylean monogenean Rajonchocotyle emarginata from the gills of the elasmobranch Amblyraja radiata. The haptor possesses six equal, pedunculate suckers, each armed with a large, curved, hooked sclerite, and an appendix bearing two small, terminal suckers and a pair of minute hamuli. The outer side of the distal region of the hooked sclerite forms a large bulge along the antero-lateral side of each sucker and the proximal region forms a small bulge on the opposite postero-lateral side; part of the large bulge, which covers the small sclerite hook, surmounts the sucker rim. The sucker sclerite is situated outside the main sucker muscle complex of the sucker wall and is surrounded by its own muscular envelope; close to the sclerite itself, long, tightly packed lamella-like processes of sarcoplasm are present. A muscular sphincter surrounds the distal region of the sclerite shaft. The sclerite consists of three heterogeneous layers, but its hook region is distinguished from the shaft by the presence of an additional homogeneous layer. Hamuli within the appendix consist of three distinct layers loosely surrounded by sarcoplasmic lamellae. The luminal surface of the appendicular suckers is covered with unusual, long, thin, interconnected surface protrusions. In all other regions of the haptor, the tegumental surface is smooth, with numerous shallow pores penetrating the "terminal web" of the syncytial cytoplasm. Unicellular gland cells are localized close to the base of the appendix, with their ducts, containing non-homogenous secretory bodies, opening onto the anterior haptoral surface. Two types of sense receptors are visible on the haptoral surface. The ultrastructural features of the haptor are discussed in relation to our understanding of their function and the evolutionary relationships of the basal polyopisthocotylean monogenean groups Hexabothriidae and Chimaericolidae.

Genotype and Phenotype of Echinococcus granulosus Derived from Wild Sheep (Ovis orientalis) in Iran.

The aim of the present study is to determine the characteristics of genotype and phenotype of Echinococcus granulosus derived from wild sheep and to compare them with the strains of E. granulosus sensu stricto (sheep-dog) and E. granulosus camel strain (camel-dog) in Iran. In Khojir National Park, near Tehran, Iran, a fertile hydatid cyst was recently found in the liver of a dead wild sheep (Ovis orientalis). The number of protoscolices (n=6,000) proved enough for an experimental infection in a dog. The characteristics of large and small hooks of metacestode were statistically determined as the sensu stricto strain but not the camel strain (P=0.5). To determine E. granulosus genotype, 20 adult worms of this type were collected from the infected dog. The second internal transcribed spacer (ITS2) of the nuclear ribosomal DNA (rDNA) and cytochrome c oxidase 1 subunit (COX1) of the mitochondrial DNA were amplified from individual adult worm by PCR. Subsequently, the PCR product was sequenced by Sanger method. The lengths of ITS2 and COX1 sequences were 378 and 857 bp, respectively, for all the sequenced samples. The amplified DNA sequences from both ribosomal and mitochondrial genes were highly similar (99% and 98%, respectively) to that of the ovine strain in the GenBank database. The results of the present study indicate that the morpho-molecular features and characteristics of E. granulosus in the Iranian wild sheep are the same as those of the sheep-dog E. granulosus sensu stricto strain.

PARÁMETROS BIOLÓGICO-PESQUEROS DEL STRIPED CHUB (KYPHOSUS INCISOR) RELEVANTES PARA SU MANEJO Y CONSERVACIÓN EN EL PARQUE NACIONAL NATURAL OLD PROVIDENCE McBEAN LAGOON

Some parameters of the fiheries biology of Kyphosus incisor (yellow chub) were estimated from fiheries monitoring and a hand line and hook size selectivity experiment carried out in the Old Providence McBean Lagoon National Park from 2006 to 2012. Both monitoring and fihing experiment were conducted to obtain scientifi information for management and conservation of K. incisor, including the active participation of islander fiherman, which favored outcomes of interest to the management of the Park. Size range for fihes was 26.5-58.0 cm total length (TL), showing allometric growth [W (g) = 0.02 LT (cm) 2.95]. There was no statistically signifiant deviation from the 1:1 sex ratio. The mean size at maturity (MSM) for females was estimated at 47.4 cm TL (95% CI, 47.1 - 47.6 cm), whereas the proportion of advanced stages of maturity increased during the second half of year, which suggests that spawning peaks occur between December and March. Size composition of catch time series suggested that this species is harvested in sizes close to the MSM; however, the indicator (mean catch size /MSM) trend was growing. The selectivity experiment aimed at comparing the fih size caught by three different J-style hook sizes, standardizing other sources of variation, in order to determine the hook size that maximizes the probability of catching fih above the MSM (9 hook). Management and conservation measures of K. incisor obtained from this study are as follow: I) in the hypothetical case of a ban, it must be established consistent with the reproductive peak of the species, i.e. between December and March; II) minimum capture legal size should be between 47 and 48 cm total length, III) restrict the use of small hooks (10 or lower); IV) increase in fihing effort with the entry of new fihermen should not be allowed; V) process of management measures by fihing agreements with resource users should continue.

Evidence for Magnetoreception in Red Drum (Sciaenops ocellatus), Black Drum (Pogonias cromis), and Sea Catfish (Ariopsis felis)

<p>Over the past few decades, magnetoreception has been discovered in several species of teleost and elasmobranch fishes by employing varied experimental methods including conditioning experiments, observations of alignment with external fields, and experiments with magnetic deterrents. Biogenic magnetite has been confirmed to be an important receptor mechanism in some species, but there is ongoing debate regarding whether other mechanisms are at work. This paper presents evidence for magnetoreception in three additional species, red drum (<em>Sciaenops</em><em> ocellatus</em>), black drum (<em>Pogonias</em><em> </em><em>cromis</em>), and sea catfish (<em>Ariopsis</em><em> </em><em>felis</em>), by employing experiments to test whether fish respond differently to bait on a magnetic hook than on a control. In red drum, the control hook outcaught the magnetic hook by 32-18 for Χ<sup>2</sup>=3.92 and a <em>P</em>-value of 0.048. Black drum showed a significant attraction for the magnetic hook, which prevailed over the control hook by 11-3 for Χ<sup>2</sup>=4.57 and a <em>P</em>-value of 0.033. Gafftopsail catfish (<em>Bagre</em><em> marinus</em>) showed no preference with a 31-35 split between magnetic hook and control for Χ<sup>2</sup>=0.242 and a <em>P</em>-value of 0.623. In a sample of 100 sea catfish in an analogous experiment using smaller hooks, the control hook was preferred 62-38 for Χ<sup>2</sup>=5.76 and a <em>P</em>-value of < 0.001. Such a simple method for identifying magnetoreceptive species may quickly expand the number of known magnetoreceptive species and allow for easier access to magnetoreceptive species and thus facilitate testing of magnetoreceptive hypotheses.</p>

Philocorydoras longus sp. n. (Monogenea, Dactylogyridae) from the gills of Hoplosternum littorale (Siluriformes, Callichthyidae) in Southeastern Brazil and the reassignment of two species from the genus Urocleidoides to Philocorydoras

Summary Philocorydoras longus sp. n. (Dactylogryridae) is described from the gills of the freshwater fish Hoplosternum littorale (Hancock, 1828) (Callichthyidae) from Jurumirim reservoir, Upper Paranapanema River, São Paulo State, Brazil. This new species belongs to the genus Philocorydoras mainly by possessing a curved cirrus accompanied by an accessory piece attached by a conspicuous filament. Philocorydoras longus sp. n. most resembles P. platensis, but differs by having delicate and smaller hooks, grooves in ventral and dorsal anchors, larger cirrus and accessory piece, and ventral bar with a long postero-medial process. Two species of the genus Urocleidoides (U. corydori Molnar, Hanek et Fernando, 1974 and U. margolisi Molnar, Hanek et Fernando, 1974) originally described from the gills of Corydoras aeneus (Gill, 1858) from Talparo River, Trinidad (near Brazil), were transferred to the genus Philocorydoras mostly by the absence of a sinistral vaginal sclerite (i. e., the primary characters of Urocleidoides) and counterclockwise cirral rings (i.e., curved tube, and tapered anteriorly in Philocorydoras). The new species is the fourth species assigned to the genus and the first recorded for Brazil.

Redescription and osteology of Hyphessobrycon compressus (Meek) (Teleostei: Characidae), type species of the genus

The type-species of Hyphessobrycon is redescribed and its osteology provided. Hyphessobrycon compressus is distinguished from its congeners by the 41-48 (mode 45) scales in the longitudinal series; 7-9 (mode 9) scales rows between the dorsal-fin origin and the lateral line, and absence of predorsal scales. Additional useful characters include the lack of spots on the body, a dorsal fin with a black spot, and an anal fin with two large, conspicuous hooks, and several other small hooks. Hyphessobrycon milleri is proposed as a junior synonym of H. compressus . The osteology of H. compressus is discussed in detail together with comments about phylogenetic relationships of Hyphessobrycon sensu stricto .