A major developmental defect observed in several Biscayne Bay,Florida, fish species

Synopsis Stunted or missing dorsal spines or rays, sometimes accompanied by a depression in the dorsal profile, were found in 10 fish species in six families from North Biscayne Bay. The same morphological abnormality occurred inHaemulon sciurus, H. parrai, H. plumieri, Lagodon rhomboides, Archosargus rhomboidalis, Diplodus argenteus, Lutjanus griseus, Kyphosus sectatrix, Sphoeroides testudineus, andLactrophyrys quadricornis. Another morphological abnormality, scale disorientation, was found in six species:H. parrai, L. rhomboides, A. rhomboidalis, L. griseus, andAbudefduf saxatilis. Pugheadedness, jaw deformities, and other abnormalities also were observed. The occurrence of similar deformities across such a spectrum of fishes from the same location suggests the deformity was induced by something in the environment common to all these species. Although there could be other explanations for the unusual cluster of abnormalities, it is suspected that the same environmental contaminant or group of contaminants is adversely affecting a common developmental pathway of these fishes. Biscayne Bay is an urban estuary that receives agricultural, industrial, and residential run off.     

Lateral line deformities in wild and farmed sea bass (Dicentrarchus labrax,L.) and sea bream (Sparus aurata,L.)

The lateral line of aquaculture fishes has rarely been studied although it is a very important anatomical organ that could serve as an inexpensive and easy tool to distinguish farmed from wild individuals. In the present study, lateral line deformities were examined in both wild and farmed sea bass (Dicentrarchus labrax) and sea bream (Sparus aurata) specimens to try to detail all possible differences between them. In order to do so, the morphology of the trunk lateral line in wild and farmed adults was examined whereby two major deformities were observed in both species: the ‘scale pocket’ deformity (14–40% incidence in all groups) where the specialized scales are missing but the canal underneath is present and the scale print is obvious, and the ‘somatic scales’ deformity (14–56% incidence in farmed individuals only) where the missing lateral line is covered with normal somatic scales. Histological examination confirmed the macroscopic observations in that the lateral line mechanism was present – although damaged – beneath the scale pocket deformity and completely absent beneath the somatic scales deformity. It is argued that the scale pocket deformity is a result of an accident during the life of the fish whereas the somatic scales deformity is an actual deformity in development.     

Patterns of fish deformities and their association with trematode cysts in the Willamette River,Oregon

Synopsis We described skeletal deformities in Willamette River fishes from larval and juvenile specimens collected in 2002 and 2003. Deformities were found in most taxa examined but were more frequent in native broadcast spawners, especially minnows and suckers, than in native or exotic nest builders. Caudal deformities were uniformly distributed throughout the river, but precaudal deformities were more localized near the towns of Newberg and Salem (Wheatland Ferry). In northern pikeminnow, Ptychocheilus oregonensis, deformities were dependent on relative hatch date, with early season fish having about three times the deformity load as late season fish. In a subsample of northern pikeminnow and chiselmouth, Acrocheilus alutaceus, number of deformities was directly related to number of trematode metacercariae and precaudal deformities were twice as likely as caudal deformities to be associated with metacercariae. Based on a logistic regression, the probability of a precaudal deformity was dependent on number of metacercariae and geographic area with the area effect disappearing as the number of cysts increased. A separate analysis showed that some types of deformities were unlikely to be associated with metacercariae. However, even in cases where metacercariae were unlikely to be associated with deformities, metacercariae were usually present elsewhere in the fish and an indirect effect could not be dismissed. The taxonomic, spatial and temporal patterns of skeletal deformities in Willamette River fishes may be due to differences in intermediate host (snail or fish) resistance or susceptibility to parasites, to differences in life history ecology, or to anthropogenic effects that are manifest in increased precaudal deformities near Newberg and Wheatland Ferry or decreased rates elsewhere.     

Effect of saddleback syndrome and vertebral deformity on the body shape and size in hatchery-reared juvenile red spotted grouper, Epinephelus akaara (Perciformes: Serranidae): a geometric morphometric approach

This study examined how saddleback syndrome (SBS) and vertebral deformity affect the body shape and size of juvenile stage red spotted grouper, Epinephelus akaara, using the landmark‐based geometric morphometrics method. According to the criterion of skeletal conditions, three groups, i.e. vertebral deformity, SBS, and normal groups, were identified. The results revealed significant differences in body shape among the three groups, in which the vertebral‐deformed group had the deepest mid‐body, the broadest anterior part, and a shortened caudal peduncle, while the SBS group showed the shallowest mid‐body and the narrowest anterior part. The normal group had a body shape intermediate between the vertebral and SBS groups. A comparison of body size among the three groups revealed significant differences in centroid size, with the vertebral‐deformed and SBS groups showing smallest and largest centroid size, respectively. This study illuminates that not all skeletal deformities lead to smaller body size. We suggest that rearing conditions might have caused the deformities reported herein.     

Seasonal influence on head capsule deformities in Chironomus zealandicus (Hudson) (Diptera: Chironomidae)

The natural incidence of deformities in the head capsules of Chironomus zealandicus was investigated at four lake sites in the central North Island (New Zealand) in summer (December) of 1994, 1995 and 1996, and winter (June) of 1995 and 1996. Significant differences were observed in deformities between sites and seasons. Individuals from Hamurana Stream, a relatively clean site, had the lowest incidence of deformities. However, there were still significant numbers of deformed chironomids. The incidence of deformity increased in summer in larvae from all sites except Hamurana Stream. No seasonal differences were observed in larvae from Hamurana Stream. There are indications that substrate type, season and genetic factors, as well as sediment chemistry may have collectively contributed to the incidence of head capsule abnormalities in C. zealandicus.     

Studies on the appearance of skeletal anomalies in red porgy: effect of culture intensiveness,feeding habits and nutritional quality of live preys

Despite the great interest of red porgy as a new species for Mediterranean aquaculture, its commercial production is constrained by the high incidence of skeletal deformities occurring in this species under culture conditions. Several studies have been conducted to better understand the origin of these anomalies in this species, using different system intensiveness, rotifers enrichment products or rotifers docosahexaenoic acid content. The first study showed that culture intensification increased the number of fish with an extra vertebrae, what was probably related to the different nutritional quality of live preys employed in each treatment, since water temperature, salinity and genetic background were identical for the different batches of fish studied. Total incidence of skeletal abnormalities was higher in the intensive system, particularly cranial abnormalities and kyphosis in the cephalic vertebrae. In both rearing systems the most common skeletal anomalies were vertebral column disorders, lordosis and fused vertebrae, their localization along the column being affected by the culture intensiveness. Rotifer enrichment, predominantly its docosahexaenoic acid content significantly affected deformities occurrence. A marked positive effect of rotifer docosahexaenoic acid content was found on larval survival. X‐ray studies denoted elevated levels of bone abnormalities associated, in both trials, to low docosahexaenoic acid content in live preys. Among different anomalies, the presence of fused vertebrae was the most frequent deformity for both rearing trials. A 50% reduction in the number of deformed fish for each type of deformity was obtained when the larvae were fed higher docosahexaenoic acid levels, denoting the important role of this fatty acid in bone development. Further studies are needed to elucidate the importance of essential fatty acids on the development of bone deformities in fish, since the functions of these fatty acids differ among them and can lead to very different effects in fish metabolism, including bone formation.     

Community structure and biogeography of shore fishes in the Gulf of Aqaba,Red Sea

Shore fish community structure off the Jordanian Red Sea coast was determined on fringing coral reefs and in a seagrass-dominated bay at 6 m and 12 m depths. A total of 198 fish species belonging to 121 genera and 43 families was recorded. Labridae and Pomacentridae dominated the ichthyofauna in terms of species richness and Pomacentridae were most abundant. Neither diversity nor species richness was correlated to depth. The abundance of fishes was higher at the deep reef slope, due to schooling planktivorous fishes. At 12 m depth abundance of fishes at the seagrass-dominated site was higher than on the coral reefs. Multivariate analysis demonstrated a strong influence on the fish assemblages by depth and benthic habitat. Fish species richness was positively correlated with hard substrate cover and habitat diversity. Abundance of corallivores was positively linked with live hard coral cover. The assemblages of fishes were different on the shallow reef slope, deep reef slope and seagrass meadows. An analysis of the fish fauna showed that the Gulf of Aqaba harbours a higher species richness than previously reported. The comparison with fish communities on other reefs around the Arabian Peninsula and Indian Ocean supported the recognition of an Arabian subprovince within the Indian Ocean. The affinity of the Arabian Gulf ichthyofauna to the Red Sea is not clear. Received in revised form: 2 November 2001 Electronic Publication     

Population genomic response to geographic gradients by widespread and endemic fishes of the Arabian Peninsula

Genetic structure within marine species may be driven by local adaptation to their environment, or alternatively by historical processes, such as geographic isolation. The gulfs and seas bordering the Arabian Peninsula offer an ideal setting to examine connectivity patterns in coral reef fishes with respect to environmental gradients and vicariance. The Red Sea is characterized by a unique marine fauna, historical periods of desiccation and isolation, as well as environmental gradients in salinity, temperature, and primary productivity that vary both by latitude and by season. The adjacent Arabian Sea is characterized by a sharper environmental gradient, ranging from extensive coral cover and warm temperatures in the southwest, to sparse coral cover, cooler temperatures, and seasonal upwelling in the northeast. Reef fish, however, are not confined to these seas, with some Red Sea fishes extending varying distances into the northern Arabian Sea, while their pelagic larvae are presumably capable of much greater dispersal. These species must therefore cope with a diversity of conditions that invoke the possibility of steep clines in natural selection. Here, we test for genetic structure in two widespread reef fish species (a butterflyfish and surgeonfish) and eight range‐restricted butterflyfishes across the Red Sea and Arabian Sea using genome‐wide single nucleotide polymorphisms. We performed multiple matrix regression with randomization analyses on genetic distances for all species, as well as reconstructed scenarios for population subdivision in the species with signatures of isolation. We found that (a) widespread species displayed more genetic subdivision than regional endemics and (b) this genetic structure was not correlated with contemporary environmental parameters but instead may reflect historical events. We propose that the endemic species may be adapted to a diversity of local conditions, but the widespread species are instead subject to ecological filtering where different combinations of genotypes persist under divergent ecological regimes.     

The West Gondwanan Occurrence Of The Hybodontid Shark Priohybodus, And The Late Jurassic–Early Cretaceous Age Of The Tacuarembó Formation, Uruguay

Priohybodus cf. P. arambourgi is reported for the first time from the Tacuarembó Formation of Uruguay. This species is a hybodontid shark known previously only from Upper Jurassic and Lower Cretaceous deposits of Saharan Africa and the Arabian Peninsula. The material (22 isolated teeth and a dorsal fin spine) was found in a thin bone bed, associated with abundant bone fragments, scales and teeth of semionotiform fishes and theropod dinosaurs. Until now, the age of the Tacuarembó Formation has been difficult to determine because its fossil content lacked useful biostratigraphic indicators. The finding of Priohybodus cf. P. arambourgi in that unit greatly expands the palaeobiogeographic range of the species, and allows us to propose a Late Jurassic–Early Cretaceous age for the Tacuarembó Formation.     

First record of saddleback syndrome in wild parrotfish Sparisoma cretense (L., 1758) (Perciformes, Scaridae)

The saddleback syndrome is recorded for the first time in a wild fish population of the Mediterranean Sea. The deformed specimen belongs to Sparisoma cretense and presents the typical saddleback phenotype of missing spines in the dorsal fin.     

Retinoic acid isomers produce malformations in postembryonic development of the Japanese flounder,Paralichthys olivaceus

We previously reported that characteristic deformities were induced by retinoic acid (RA) treatment of the Japanese flounder, Paralichthys olivaceus, at 6-9 days post-hatching (dph). To evaluate the toxic potency of nuclear retinoid receptors in induction of deformities by RA, we here investigated the effects of retinoic acid isomers on postembryonic development of this species. Larvae were exposed to either 25 nM of all-trans RA (atRA), 9-cis RA (9cRA) or 13-cis RA (13cRA) at 6-9 dph. All RA isomers induced deformities in the lower jaw, caudal fin and vertebrae. In the lower jaw, growth retardation of the dentary was evident. In the vertebrae, the major abnormalities were hypertrophy of the centrum, central fusion, and an increase in the number of abdominal vertebrae. Caudal fin deformities included deformity of caudal bone complex and absence of the entire caudal fin. The absence of the hypural primordium at 12 dph was the first sign of abnormality in caudal fin development, and resulted in complete blocking of the caudal fin development. Among the RA isomers, atRA induced the most severe deformity in all skeletons examined. Retinoic acid receptor (RAR) expression was activated by atRA and 9cRA, and pitx2 expression was inhibited in the lower jaw by atRA and 9cRA. Vitamin D receptor (VDR) expression was specifically inhibited by atRA treatment, suggesting that RA inhibits the lower jaw growth by suppressing the expression of these genes. These results suggest that RA exerted toxic effects on the skeletal systems, mainly through the RAR pathway.     

Effect of rearing techniques on skeletal deformities and osteological development in red porgy Pagrus pagrus (Linnaeus, 1758) larvae

Red porgy is a candidate species for marine aquaculture diversification. The objective of the present study was to describe the osteological development in this species and the occurrence of skeletal deformities in relation to the intensification of the rearing system. Fish samples were periodically collected along the development from hatching to juveniles (95 days after hatching). Osteological development and the presence of skeleton abnormalities were evaluated. Larvae reared under S‐IS showed a better growth in terms of total length in comparison with IS reared ones. Regarding to osteological development for red porgy, this was similar between fish from both culture systems, but differing in timing of apparition and ossification of skeletal elements. X‐ray studies revealed a high number of fish with skeletal deformities (Semi‐intensive: 38.8%; Intensive: 46.5%), but no significant effect of the rearing technique on the incidence of deformities such as lordosis or fused vertebrae was found. However, cranial abnormalities and kyphosis incidences were significantly higher in intensive system cultured red porgy. These results, suggest a relationship among rearing technique, osteological development and the apparition of certain deformities.     

Gonapodasmius epinepheli n. sp. (Didymozoidae) from the grouper Epinephelus tauvina from the Arabian Gulf

A new species, Gonapodasmius epinepheli (Didymozoidae: Gonapodasmiinae), is described from the fish Epinephelus tauvina from the Arabian Gulf. It differs from most other members of the genus in the presence of a bulbous swelling at the distal end of the ovary, the presence of a characteristic bulge in the genital junction region, in the dense mass of glandular cells around the intestinal limbs and in the presence of an empty metraterm and vas deferens in the male and female respectively. The new species represents the first record of a didymozoid trematode from fishes in the Arabian Gulf.     

Morphological deformities occurring in Belarusian chironomids (Diptera: Chironomidae) subsequent to the Chernobyl nuclear disaster

1. Chironomid larvae and adults were collected from several freshwater habitats around the Chernobyl site from 1990 to 1994 (4–8 years after a nuclear accident) and examined for morphological deformities.
2. Deformities were found in larvae of nine of the 13 species collected, and were most obvious in headcapsule structures, particularly the antennae, mentum, mandibles and epipharyngeal pectens.
3. In species of Chironomus , the most abundant genus, there was a positive linear relationship between the incidence of deformity and radiation level. Indices of severity of deformity showed similar trends. It is suggested that these deformities resulted largely from ingestion of irradiated, plant-derived, fine particulate food.
4. Among adult male Ch. riparius , the deformity index decreased both with increasing time from the accident and with increasing distance from the reactor, although these trends were not statistically significant. There was also a trend of increased severity of deformity closer to the accident, both in time and space.
5. Overall, there was a greater incidence of deformity in the larvae than in the adults (e.g. 60 versus 20%, respectively, at the Krasnoselye site and 33 versus 20%, respectively, at the more distant Dron'ki site).
6. It was not possible to determine whether the deformities were inherited from previous generations or were somatic occurrences in each new generation as a consequence of the radiation that continues to pervade the region.     

Diatom teratologies as biomarkers of contamination: Are all deformities ecologically meaningful?

Contaminant-related stress on aquatic biota is difficult to assess when lethal impacts are not observed. Diatoms, by displaying deformities (teratologies) in their valves, have the potential to reflect sub-lethal responses to environmental stressors such as metals and organic compounds. For this reason, there is great interest in using diatom morphological aberrations in biomonitoring. However, the detection and mostly the quantification of teratologies is still a challenge; not all studies have succeeded in showing a relationship between the proportion of abnormal valves and contamination level along a gradient of exposure. This limitation in part reflects the loss of ecological information from diatom teratologies during analyses when all deformities are considered. The type of deformity, the severity of aberration, species proneness to deformity formation, and propagation of deformities throughout the population are key components and constraints in quantifying teratologies. Before a metric based on diatom deformities can be used as an indicator of contamination, it is important to better understand the “ecological signal” provided by this biomarker. Using the overall abundance of teratologies has proved to be an excellent tool for identifying contaminated and non-contaminated environments (presence/absence), but refining this biomonitoring approach may bring additional insights allowing for a better assessment of contamination level along a gradient. The dilemma: are all teratologies significant, equal and/or meaningful in assessing changing levels of contamination? This viewpoint article examines numerous interrogatives relative to the use of diatom teratologies in water quality monitoring, provides selected examples of differential responses to contamination, and proposes solutions that may refine our understanding and quantification of the stress. This paper highlights the logistical problems associated with accurately evaluating and interpreting teratologies and stimulates more discussion and research on the subject to enhance the sensitivity of this metric in bioassessments.     

Caudal nasal deviation

Caudal nasal deviation, manifested by a "crooked tip," asymmetric nostrils, and a deviated columella, is one of the most challenging deformities encountered in rhinoplasty. This entity is often ignored by rhinoplasty surgeons, on the basis of the assumption that correction of other segments of the deviated nose will improve the caudal nose. Failure to correct this imperfection (or, occasionally, deformity) invariably produces suboptimal results. The nasal structures involved in caudal nasal deviation, namely, the septum, the lower lateral cartilages, and the anterior nasal spine, must be evaluated for identification of the anatomical blocks that have a causative role in caudal nasal deviation. The specific structures with abnormalities related to this deformity are discussed, as are techniques for the correction of the deformities. These techniques significantly augment the surgeon's repertoire of methods for addressing the subtleties of caudal nasal deviation correction and achieving predictable results.     

Structure of supporting elements in the dorsal fin of percid fishes

The dorsal fin is one of the most varied swimming structures in Acanthomorpha, the spiny‐finned fishes. This fin can be present as a single contiguous structure supported by bony spines and soft lepidotrichia, or it may be divided into an anterior, spiny dorsal fin and a posterior, soft dorsal fin. The freshwater fish family Percidae exhibits especially great variation in dorsal fin spacing, including fishes with separated fins of varying gap length and fishes with contiguous fins. We hypothesized that fishes with separated dorsal fins, especially those with large gaps between fins, would have stiffened fin elements at the leading edge of the soft dorsal fin to resist hydrodynamic loading during locomotion. For 10 percid species, we measured the spacing between dorsal fins and calculated the second moment of area of selected spines and lepidotrichia from museum specimens. There was no significant relationship between the spacing between dorsal fins and the second moment of area of the leading edge of the soft dorsal fin.     

A HOX gene mutation in a family with isolated congenital vertical talus and Charcot-Marie-Tooth disease

Congenital vertical talus (CVT), also known as "rocker-bottom foot" deformity, is a dislocation of the talonavicular joint, with rigid dorsal dislocation of the navicular over the neck of the talus. This condition is usually associated with multiple other congenital deformities and only rarely is an isolated deformity. The reported familial cases are consistent with an autosomal dominant mode of inheritance with incomplete penetrance. In contrast, Charcot-Marie-Tooth disease (CMT) is thought to be a completely distinct heterogeneous group of disorders, with foot abnormalities that typically develop a high-arched "claw foot" appearance later in life. In the present study, DNA was isolated from 36 members of a single upstate (northern) New York white family of Italian descent in which both CVT and CMT were segregating. Whole-genome linkage analysis with Affymetrix GeneChip Mapping 10K Array defined a 7-Mb critical region on chromosome 2q31, which led to candidate-gene sequencing of six HOX genes and detection of a single missense mutation, M319K (956T-->A), in the HOXD10 gene. In the study family, this mutation was fully penetrant and exhibited significant evidence of linkage (LOD 6.33; theta =0), and it very likely accounts for both CVT and CMT in heterozygotes.     

Molecular and Morphometric Characteristics of Ceratomyxa hamour n. sp. (Myxosporea: Bivalvulida) Infecting the Gallbladder of the Orange‐spotted Grouper Epinephelus coioides from the Arabian Gulf,Saudi Arabia

Ceratomyxa hamour n. sp. was found to infect the gallbladder of the orange‐spotted grouper, Epinephelus coioides located off the Saudi Arabian coast of the Arabian Gulf. The infection was reported as a free‐floating spore in the bile, and pseudoplasmodia were not observed. Mature spores were crescent‐shaped and measured on average 7 μm in length and 16 μm in thickness. The polar capsule, meanwhile, had length to width measurements of 4 μm and 3 μm on average. A periodical survey was conducted throughout a sampling period between December 2012 and December 2013, with the results showing that the parasite was present throughout the year with a mean prevalence of 32.6%. The objective of this study was to characterize this new species based on its morphological and molecular differences from previously described species. Molecular analysis based on the partial sequence of the SSU rDNA gene, showed the highest similarity (97.8%) to Ceratomyxa buri, reported in the cultured yellow tail Seriola quinqueradiata in Japan. Indeed, C. buri and the new species described here formed an individual cluster with a high degree of bootstrap support. This is the first reported species of genus Ceratomyxa from the Arabian Gulf fishes off Saudi Arabia.     

Assessment of rates of deformity in wild frog populations using in situ cages: a case study of Leopard Frogs (Rana pipiens) in Ontario, Canada

High rates of deformity in wild amphibian populations from north-eastern North America have been increasingly reported since 1995. In the St Lawrence River basin (Canada) elevated frequencies of limb and eye deformities in mudpuppies (Necturus maculosus) and leopard frogs (Rana pipiens) were recorded in the early 1990s. A caging study was conducted during 1998 to verify the rates recorded in leopard frogs and pursue the potential causes of deformities seen in juveniles and adults. Week-old leopard frog tadpoles were collected from a reference wetland and maintained through to metamorphosis in cages in previously identified high risk wetlands. Deformity frequencies were measured and compared with frequencies measured in wild populations of leopard frogs inhabiting the same wetlands. The results of caging studies and sampling of wild populations were also compared with corresponding data collected from a reference wetland. No deformities were observed in caged or wild reference animals. Very low deformity frequencies (up to 2.2%) were observed in frogs caged in high risk wetlands, but greater frequencies (3.4-10%) were observed in wild young-of-the-year frogs captured at the same sites. The types of deformities were similar among groups; they included fused, missing or extra digits and disproportionate hindlimb length or eye pupil size. In addition, mortality rates were elevated in two cages in high risk wetlands. In general, the caging procedure was effective in establishing the potential for production of deformities in the waters of a given wetland, but tended to underestimate the rates calculated for samples of wild populations. The ramifications of the first-year findings for similar assessments of amphibian deformity rates and establishment of cause-effect linkages are discussed.