Vocal repertoire and sound characteristics in the variegated cardinalfish, Fowleria variegata (Pisces: Apogonidae).

The variegated cardinalfish Fowleria variegata produces grunt and hoot calls during agonistic and courtship interactions. Both sounds are tonal and occur as single and multiunit calls. Grunts are of short duration with variable frequency spectra. Hoots are longer, have a higher fundamental frequency, and a more developed harmonic structure. Agonistic grunt calls and short hoot calls (1-2 hoots) are produced during chases and when striking an individual or a mirror. Grunts are produced primarily in male-female and mirror-image encounters, and short hoot calls are produced primarily in male-male interactions. During the reproductive period, long hoot calls (three and four hoots) are the main sound type in a mix-sexed tank and at Dongsha Atoll. These are likely produced by males because isolated females are silent, and isolated males emit long hoot calls. Courtship interactions are mostly silent, and males are silent after capturing eggs for oral brooding. Tank sounds peak at dusk to early evening with a smaller peak at noon, although there are dusk and dawn peaks at Dongsha Atoll. Tank sounds exhibit a semilunar rhythm with peaks at the new and full moon. Other cardinalfish species from the atoll produce grunts but not hoot calls.

Insecticidal Activity and Insect Repellency of Four Species of Sea Lily (Comatulida: Comatulidae) From Taiwan.

The methanol and ethyl acetate (EA) extracts of four species of sea lily (Himerometra magnipinna, Comaster multifidus, Comanthina sp., and Comatella maculata) were evaluated for their insecticidal activity against Yellow-fever mosquito larvae (Aedes aegypti) and their repellency against adult Asian Tiger mosquitoes (Aedes albopictus). The 24-hr minimum inhibition concentration (MIC) data revealed that the extracts from H. magnipinna and the C. maculata were the most active, killing mosquito larvae at 12.5 ppm. The toxicity of the extracts from these four sea lilies in descending order was H. magnipinna (12.5 ppm), C. maculata (12.5 ppm), C. multifidus (100 ppm), and Comanthina sp. (200 ppm). Furthermore, no significant difference in toxicity was found using either EA or methanol as the extraction solvent. The MIC at 12.5 ppm is promising as an insecticide lead. The repellency study results show that EA is a better solvent for one species (H. magnipinna), but the methanol is a better solvent overall. The repellency of these sea lily extracts in descending order was Comanthina sp. MeOH (ED50 at 0.32%), followed by H. magnipinna EA (ED50 at 0.38%), C. multifidus MeOH (ED50 at 0.57%), C. maculata MeOH (ED50 at 0.76%), C. multifidus EA (ED50 at 1.25%), and H. magnipinna MeOH (ED50 at 1.67%). A compound with ED50 <0.5% is considered to be a promising repellant. Among the studied sea lilies, both Comanthina sp. and H. magnipinna have potential to be further developed as mosquito control agents due to their favorable toxicity and repellency.

A multi-gene dataset reveals a tropical New World origin and Early Miocene diversification of croakers (Perciformes: Sciaenidae).

Widely distributed groups of living animals, such as the predominantly marine fish family Sciaenidae, have always attracted the attention of biogeographers to document the origins and patterns of diversification in time and space. In this study, the historical biogeography of the global Sciaenidae is reconstructed within a molecular phylogenetic framework to investigate their origin and to test the hypotheses explaining the present-day biogeographic patterns. Our data matrix comprises six mitochondrial and nuclear genes in 93 globally sampled sciaenid species from 52 genera. Within the inferred phylogenetic tree of the Sciaenidae, we identify 15 main and well-supported lineages; some of which have not been recognized previously. Reconstruction of habitat preferences shows repeated habitat transitions between marine and euryhaline environments. This implies that sciaenids can easily adapt to some variations in salinity, possibly as the consequence of their nearshore habitats and migratory life history. Conversely, complete marine/euryhaline to freshwater transitions occurred only three times, in South America, North America and South Asia. Ancestral range reconstruction analysis concomitant with fossil evidence indicates that sciaenids first originated and diversified in the tropical America during the Oligocene to Early Miocene before undergoing two range expansions, to Eastern Atlantic and to the Indo-West Pacific where a maximum species richness is observed. The uncommon biogeographic pattern identified is discussed in relation to current knowledge on origin of gradients of marine biodiversity toward the center of origin hypothesis in the Indo-West Pacific.

Mozart K.448 listening decreased seizure recurrence and epileptiform discharges in children with first unprovoked seizures: a randomized controlled study.

BACKGROUND: Increasing numbers of reports show the beneficial effects of listening to Mozart music in decreasing epileptiform discharges as well as seizure frequency in epileptic children. There has been no effective method to reduce seizure recurrence after the first unprovoked seizure until now. In this study, we investigated the effect of listening to Mozart K.448 in reducing the seizure recurrence rate in children with first unprovoked seizures. METHODS: Forty-eight children who experienced their first unprovoked seizure with epileptiform discharges were included in the study. They were randomly placed into treatment (n = 24) and control (n = 24) groups. Children in the treatment group listened to Mozart K.448 daily before bedtime for at least six months. Two patients in the treatment group were excluded from analysis due to discontinuation intervention. Finally, forty-six patients were analyzed. Most of these patients (89.1%) were idiopathic in etiology. Seizure recurrence rates and reduction of epileptiform discharges were compared. RESULTS: The average follow-up durations in the treatment and control groups were 18.6 ± 6.6 and 20.1 ± 5.1 months, respectively. The seizure recurrence rate was estimated to be significantly lower in the treatment group than the control group over 24 months (37.2% vs. 76.8%, p = 0.0109). Significant decreases in epileptiform discharges were also observed after 1, 2, and 6 months of listening to Mozart K.448 when compared with EEGs before listening to music. There were no significant differences in gender, mentality, seizure type, and etiology between the recurrence and non-recurrence groups. CONCLUSIONS: Although the case number was limited and control music was not performed in this study, the study revealed that listening to Mozart K.448 reduced the seizure recurrence rate and epileptiform discharges in children with first unprovoked seizures, especially of idiopathic etiology. We believe that Mozart K.448 could be a promising alternative treatment in patients with first unprovoked seizures and abnormal EEGs. Further large-scaled study should be conducted to confirm the effect. TRIAL REGISTRATION: NCT01892605, date: June-19-2013.

Music and movement therapy improves quality of life and attention and associated electroencephalogram changes in patients with attention-deficit/hyperactivity disorder.

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) is the most common neurobehavioral disorder. Treatments for ADHD include pharmacological and nonpharmacological therapy. However, pharmacological treatments have side effects such as poor appetite, sleep disturbance, and headache. Moreover, nonpharmacological treatments are not effective in ameliorating core symptoms and are time-consuming. Hence, developing an alternative and effective treatment without (or with fewer) side effects is crucial. Music therapy has long been used to treat numerous neurological diseases. Although listening to music is beneficial for mood and cognitive functions in patients with ADHD, research on the effects of music and movement therapy in children with ADHD is lacking. METHODS: The present study investigated the effects of an 8-week music and movement intervention in 13 children with ADHD. The Pediatric Quality of Life Inventory (PedsQL) was used to evaluate changes in participants' quality of life. Conners' Kiddie Continuous Performance Test (K-CPT 2) and the Swanson, Nolan, and Pelham rating scale (SNAP-IV) were used to assess core symptoms. Electroencephalogram (EEG) recordings were analyzed to determine neurophysiological changes. RESULTS: The results revealed that the participants' quality of life increased significantly after the 8-week intervention. Furthermore, the participants' hit reaction times in the block 1 and block 2 tests of K-CPT 2 decreased significantly after the intervention. EEG analysis demonstrated an increase in alpha power and Higuchi's fractal dimension and a decrease in delta power in certain EEG channels. CONCLUSION: Our music and movement intervention is a potential alternative and effective tool for ADHD treatment and it can significantly improve patients' quality of life and attention.

Comparative proteomics analysis of degenerative eye lenses of nocturnal rice eel and catfish as compared to diurnal zebrafish.

PURPOSE: The aim of this study was to determine the lens crystallin diversity of degenerative eyes from the rice eel (Monopterus albus) and walking catfish (Clarias batrachus) as compared to that of zebrafish (Danio rerio) by using comparative proteomics methodologies. We endeavored to investigate the evolution of vertebrate lenses particularly concerning the functional loss of lenses in degenerative eyes of rice eels and catfishes living under an environment of perpetual darkness. METHODS: Fish lenses were collected and homogenized to extract total soluble proteins. The protein mixtures were separated by one- and two-dimensional gel electrophoresis (1D or 2D gel), plus the newer gel-free shotgun proteomic strategy, followed by in-gel digestion and subjection of the digested protein bands or spots to liquid chromatography coupled with tandem mass spectrometry. The proteomics data were analyzed and compared based on the proteomics databank of zebrafish. The soluble lens protein solutions of three piscine species were also processed by gel-filtration chromatography and 1D sodium dodecyl sulfate-polyacrylamide gel electrophoresis for the comparison and validation of various crystallin families, e.g., α-, ß-, and γ-crystallins. RESULTS: In zebrafish eye lenses, γ-crystallin constituted about 71% and α- and ß-crystallins comprised 30% of total lens proteins. In rice eel lenses, very little or almost no α-crystallins were detected and ß- and γ-crystallins comprised more than 98% of total lens proteins. In catfish lenses, α- and ß-crystallins comprised about 40% and γ-crystallin constitutes 60% of total lens proteins. It was of interest to find that α-crystallin was totally absent in the rice eel in contrast to the presence, albeit with very low amounts, of α-crystallin in similarly nocturnal catfish. The ratio of α-crystallin subunits (αA/αB) was found to be about 20:1 for the catfish lens, in great contrast to the ratio of about 3:1 found for most mammalian lenses. In contrast, ß- and γ-crystallins were more abundant in lenses of these three piscine species, similar to mammalian lenses. By proteomics analysis, the most abundant ß-crystallins were found to comprise a diverse group of ßA1a, ßA1-2, ßA2a, ßA2-2, ßA4, ßB1, ßB2, and ßB3 subunit crystallins; the monomeric γ-crystallin class contains γB, γD, γM2, γM3, γM5, γM7, γN-A, γN-B, γS1, and γS2 crystallins. CONCLUSIONS: In cave or nocturnal animals, the eye is sometimes reduced or eliminated because of adaptation to life in visual darkness. The comparative proteomics analysis of degenerative and normal lenses forms a firm molecular basis to investigate further the evolution of piscine lenses in the future. The total numbers of α-, ß-, and γ-crystallins in the three fish species as revealed by the current proteomics methodology clearly indicate the complexity and diversity of crystallin species present in the piscine class of vertebrates. The unexpected finding that α-crystallin is absent in the degenerative eye lenses of rice eel may have some bearing on the chaperone function of α-crystallin in regard to its protective role of preventing protein aggregation in diurnal vertebrate lenses to maintain functional transparency.

Parvalbumin characteristics in the sonic muscle of a freshwater ornamental grunting toadfish (Allenbatrachus grunniens).

The grunting toadfish, Allenbatrachus grunniens, is an ornamental fish in freshwater aquariums, and it has the ability to produce sounds. The sonic muscle of the toadfish is the fastest vertebrate muscle ever measured, and the rates of Ca(2+) transport and cross-bridge dissociation are also the fastest. Parvalbumins (PAs) are Ca(2+)-binding proteins that help in muscle relaxation in vertebrates. Several PA isoforms have been identified in variable ratios in different muscle types. Both male and female grunting toadfish have intrinsic sonic muscles attached to their swim bladders, but no significant difference in morphology between male and female sonic muscles has been observed. In this study, we used SDS-PAGE and western blotting to characterize the total PA expression and to identify the PAs from the sonic muscle and the white body muscle of A. grunniens. Although the total PA concentrations were similar in sonic and white muscles, there were differences in the isoform percentages. Two and four PA isoforms were identified from sonic muscle and white muscle, respectively. The estimated sizes of PA1, PA2, and PA3 in the sonic muscle of the grunting toadfish were 10, 10.5, and 10.5 kDa, respectively, and the isoelectric points of PA1, PA2, and PA3 in the grunting toadfish were 4.77, 4.58, and 4.42, respectively. In the sonic muscle, the primary PA isoform was PA1, which comprised more than 94 % of total PA, whereas PA2 comprised only 5 % of the total PA content. In contrast, in white muscle, the primary isoform was PA2, which comprised 58 % of the total PA. Both PA1 (with PA1a) and PA3 represented approximately 20 % of the total PA in white muscle. These results indicate that there is no positive correlation between a high PA content and the speed of muscle relaxation; however, PA1 might have the greatest effect on the relaxation of the grunting toadfish's sonic muscle.

Environmental assessment of trace element bioaccumulation in sipunculan from seagrass and wetland sediments.

This study is the first measurement of trace elements in sipunculan and their surrounding sediments. The bioaccumulation characteristics of arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), and zinc (Zn) were analyzed and compared in two sipunculan species, Sipuncula nudus and Siphonosoma vastum, which were collected from seagrass beds and wetlands in Taiwan. The sipunculan and sediment samples were analyzed using an inductively coupled plasma mass spectrometer. Both sipunculan in the wetlands and seagrass beds had a high Cu bioaccumulation mechanism. Multivariate analysis, principle component analysis, and partial least squares for discriminant analysis of trace element levels and bioaccumulation factors were used to distinguish the element distributions that corresponded to the two habitats (seagrass beds and wetlands). Different levels of certain trace elements in these two sipunculan species may result not only from the environmental factors of various habitats but also from the accumulation characteristics of various species. The As, Cd, Cr, Cu, Hg, and Zn concentrations were markedly lower in sipunculan than in other invertebrates from the adjacent polluted regions. The public health issues regarding the consumption of sipunculan are also discussed.

Mozart k.545 mimics mozart k.448 in reducing epileptiform discharges in epileptic children.

Mozart K.448 has been shown to improve cognitive function, leading to what is known as the Mozart Effect. Our previous work reveals positive effects of Mozart K.448 in reducing epileptiform discharges in epileptic children. In this study, we evaluated the effect of Mozart K.545 and compared the effects with those of Mozart K.448 on epileptiform discharges in children with epilepsy. Thirty-nine epileptic children with epileptiform discharges were included in the study. They received electroencephalogram examinations before, during, and after listening to Mozart K.448 and K.545, one week apart, respectively. The frequencies of epileptiform discharges were compared. There was a significant decrease in the frequency of epileptiform discharges during and right after listening to Mozart K.448 and K.545 (reduced by 35.7 ± 32.7% during Mozart K.448 and 30.3 ± 44.4% after Mozart K.448; and 34.0 ± 39.5% during Mozart K.545 and 31.8 ± 39.2% after Mozart K.545). Spectrogrammatic analysis of the two pieces of music demonstrated that both share similar spectrogrammatic characteristics. Listening to Mozart K.448 and K.545 decreased the epileptiform discharges in epileptic children. This suggests that Mozart K.448 is not the only piece of music to have beneficial effects on children with epilepsy. Other music with lower harmonics may also decrease epileptiform discharges in epileptic children.

An Intermediate in the evolution of superfast sonic muscles.

BACKGROUND: Intermediate forms in the evolution of new adaptations such as transitions from water to land and the evolution of flight are often poorly understood. Similarly, the evolution of superfast sonic muscles in fishes, often considered the fastest muscles in vertebrates, has been a mystery because slow bladder movement does not generate sound. Slow muscles that stretch the swimbladder and then produce sound during recoil have recently been discovered in ophidiiform fishes. Here we describe the disturbance call (produced when fish are held) and sonic mechanism in an unrelated perciform pearl perch (Glaucosomatidae) that represents an intermediate condition in the evolution of super-fast sonic muscles. RESULTS: The pearl perch disturbance call is a two-part sound produced by a fast sonic muscle that rapidly stretches the bladder and an antagonistic tendon-smooth muscle combination (part 1) causing the tendon and bladder to snap back (part 2) generating a higher-frequency and greater-amplitude pulse. The smooth muscle is confirmed by electron microscopy and protein analysis. To our knowledge smooth muscle attachment to a tendon is unknown in animals. CONCLUSION: The pearl perch, an advanced perciform teleost unrelated to ophidiiform fishes, uses a slow type mechanism to produce the major portion of the sound pulse during recoil, but the swimbladder is stretched by a fast muscle. Similarities between the two unrelated lineages, suggest independent and convergent evolution of sonic muscles and indicate intermediate forms in the evolution of superfast muscles.

Mozart K.448 acts as a potential add-on therapy in children with refractory epilepsy.

Mozart's Sonata for two pianos in D major, K.448 (Mozart K.448), has been shown to improve mental function, leading to what is known as the Mozart effect. Our previous work revealed that epileptiform discharges in children with epilepsy decreased during and immediately after listening to Mozart K.448. In this study, we evaluated the long-term effects of Mozart K.448 on children with refractory epilepsy. Eleven children with refractory epilepsy were enrolled. All of the patients were diagnosed as having had refractory epilepsy for more than 1 year (range =1 year to 6 years 4 months, mean =3 years 11 months) and had been receiving at least two antiepileptic drugs (AED). During the study period, they listened to Mozart K.448 once a day before bedtime for 6 months. Seizure frequencies were recorded 6 months before they started listening to this music and monthly during the study period. All of the patients remained on the same AEDs during the 6-month study period. Frequencies of seizures were compared before and after listening to Mozart K.448. Eight of eleven patients were seizure free (N=2) or had very good responses (N=6) after 6 months of listening to Mozart K.448. The remaining three (27.3%) showed minimal or no effect (effectiveness <50%; unmodified or worsened seizure frequency). The average seizure reduction was 53.6 ± 62.0%. There were no significant differences in seizure reduction with IQ, etiology, or gender. We conclude that Mozart K.448 should be further studied as a potential add-on therapy in the treatment of children with refractory epilepsy.

The long-term effect of listening to Mozart K.448 decreases epileptiform discharges in children with epilepsy.

Mozart's Sonata for Two Pianos in D major, K.448 (Mozart K.448), has been shown to improve mental function, leading to what is known as the Mozart Effect. Our previous work revealed that epileptiform discharges in children with epilepsy decrease during and right after listening to Mozart K.448. However, the duration of the effect was not studied. In the study described here, we evaluated the long-term effect of Mozart K.448 on epileptiform discharges in children with epilepsy. Eighteen children with epilepsy whose seizures were clinically well controlled with antiepileptic drugs were included. For each child, EEGs had revealed persistent epileptiform discharges for at least 6 months. These patients listened to Mozart K.448 for 8 minutes once a day before bedtime for 6 months. Epileptiform discharges were recorded and compared before and after 1, 2, and 6 months of listening to Mozart K.448. All of the children remained on the same antiepileptic drug over the 6 months. Relationships between number of epileptiform discharges and foci of discharges, intelligence, epilepsy etiology, age, and gender were analyzed. Epileptiform discharges significantly decreased by 53.2±47.4, 64.4±47.1, and 71.6±45.8%, respectively, after listening to Mozart K.448 for 1, 2, and 6 months. All patients except those with occipital discharges showed a significant decrease in epileptiform discharges. Patients with normal intelligence and idiopathic epilepsy had greater decreases than those with mental retardation and symptomatic epilepsy. Age and gender did not affect the results. We conclude that long-term listening to Mozart K.448 may be effective in decreasing epileptiform discharges in children with epilepsy in a chronologically progressive manner.

Study on the accumulation of heavy metals in shallow-water and deep-sea hagfishes.

Hagfish, the plesiomorphic sister group of all vertebrates, are scavengers, and many of them live at depths reaching thousands of meters. They are caught for use as food and serve as a substitute for leather in crafts in Asian hagfisheries. At present, the amount of various pollutants present in hagfishes from bioaccumulation through the food chain is unknown. To understand the bioaccumulation characteristics of heavy metals in deep-sea scavengers, selected heavy metals, including iron (Fe), manganese (Mn), copper (Cu), zinc (Zn), arsenic (As), selenium (Se), cadmium (Cd), mercury (Hg), and lead (Pb), were analyzed and compared in two hagfish species, Paramyxine nelsoni (Pn) (found at approximately 200 m) and Myxine formosana (Mf) (found at approximately 850 m) caught in southwestern Taiwanese waters. Hagfish muscle (PnM and MfM) and liver (PnL and MfL) samples were lyophilized, and their metal levels were then analyzed using an inductively coupled plasma mass spectrometer. The metals with the highest levels in Pn tissues included Cu and As (PnL > MfL and PnM > MfM); in contrast, those that were higher in Mf tissues were Cd, Hg (both MfL > PnL and MfM > PnM), and Zn (MfM > PnM). Multivariate analyses, i.e., principle component analysis and partial least squares for discriminant analysis of metal levels were able to clearly separate these four tissue types into two groups corresponding to the two species: Pn and Mf. The present data also show differences in the levels of certain heavy metals in these tissues of the two hagfish species. These differences might have resulted not only from depth-related environmental factors but also from different species' accumulation characteristics. Fe, Cu, and Hg concentrations were much higher in hagfish muscle than have been found in other fishes from adjacent polluted regions, and Hg was approximately 10- to 100-fold higher in hagfish muscles. Public health issues related to the consumption of hagfish are also discussed.

A NMR-based metabolomic approach for differentiation of hagfish dental and somatic skeletal muscles.

The hagfish dental muscle is a large and specialized element of the feeding apparatus that helps ingest food. This muscle has enzymatic activities and contractile properties different from the hagfish somatic skeletal muscle. To verify the functional relevance of protein alterations, we examined the metabolomic differentiation of hagfish dental and somatic skeletal muscles using ¹H-nuclear magnetic resonance (NMR)-based metabolomics and multivariate analysis that separated hagfish dental and somatic muscles by principal component analysis and partial least squares for discriminant analysis. Our analysis of assigned metabolites showed that anserine and taurine levels were higher in dental muscle, but creatine, fructose, glucose, glycerate, pyruvate, and succinate levels were higher in somatic muscle. We concluded that the primary energy sources of dental and somatic muscles are related to the citric acid cycle and the anaerobic glycolysis and metabolism of creatine. Thus, ¹H-NMR-based metabolomics can be integrated with the previous proteomic approach to derive biochemical and physiological information about hagfish muscles.

Seasonal changes in atrophy-associated proteins of the sonic muscle in the big-snout croaker, Johnius macrorhynus (Pisces, Sciaenidae), identified by using a proteomic approach.

In most sciaenids, males possess sonic muscles and produce sound through the contraction of these muscles and amplification of the swim bladder. The sonic muscles in some fishes exhibit seasonal changes in size. For example, they are hypertrophic in the spawning season, and atrophic in the non-spawning months. The protein profiles of the sonic muscle, red muscle, and white muscle in the Johnius macrorhynus were shown by two-dimensional electrophoresis (2-DE) and were compared to reveal differential protein expressions. About 80 up-regulated protein spots in the sonic muscle, and 30 spots related to six contractile proteins (fast muscle myosin heavy chain, skeletal alpha actin, alpha actin cardiac, tropomyosin, myosin light chain 2, and myosin light chain 3), four energy metabolic enzymes (enolase, acyl-CoA synthetase, creatine kinase, and cytochrome P450 monooxygenase), and two miscellaneous proteins (DEAD box protein and cyclin H) were identified. Seasonal hypertrophy and atrophy of the sonic muscles related to the reproductive cycle were verified in male big-snout croaker. The contents of some proteins were significantly different in the muscles under these conditions. The levels of cytochrome P450 monooxygenase, fast muscle myosin heavy chain, DEAD box proteins, isocitrate dehydrogenase, and creatine kinase were up-regulated in the hypertrophic muscle, but the levels of alpha actin cardiac, myosin light 2, and myosin light 3 were lower than in the atrophic muscle. Potential reasons for these differences in protein expression related to physiological adaptation are discussed.

A sciaenid swim bladder with long skinny fingers produces sound with an unusual frequency spectrum.

Swim bladders in sciaenid fishes function in hearing in some and sound production in almost all species. Sciaenid swim bladders vary from simple carrot-shaped to two-chambered to possessing various diverticula. Diverticula that terminate close to the ears improve hearing. Other unusual diverticula heading in a caudal direction have not been studied. The fresh-water Asian species Boesemania microlepis has an unusual swim bladder with a slightly restricted anterior region and 6 long-slender caudally-directed diverticula bilaterally. We hypothesized that these diverticula modify sound spectra. Evening advertisement calls consist of a series of multicycle tonal pulses, but the fundamental frequency and first several harmonics are missing or attenuated, and peak frequencies are high, varying between < 1-2 kHz. The fundamental frequency is reflected in the pulse repetition rate and in ripples on the frequency spectrum but not in the number of cycles within a pulse. We suggest that diverticula function as Helmholz absorbers turning the swim bladder into a high-pass filter responsible for the absence of low frequencies typically present in sciaenid calls. Further, we hypothesize that the multicycle pulses are driven by the stretched aponeuroses (flat tendons that connect the sonic muscles to the swim bladder) in this and other sciaenids.

Differential proteome analysis of hagfish dental and somatic skeletal muscles.

Hagfish, the plesiomorphic sister group of all vertebrates, are deep-sea scavengers. The large musculus (m.) longitudinalis linguae (dental muscle) is a specialized element of the feeding apparatus that facilitates the efficient ingestion of food. In this article, we compare the protein expression in hagfish dental and somatic (the m. parietalis) skeletal muscles via two-dimensional gel electrophoresis and mass spectrometry in order to characterize the former muscle. Of the 500 proteins screened, 24 were identified with significant differential expression between these muscles. The proteins that were overexpressed in the dental muscle compared to the somatic muscle were troponin C (TnC), glycogen phosphorylase, beta-enolase, fructose-bisphosphate aldolase A (aldolase A), and glyceraldehyde-3-phosphate dehydrogenase (GAPDH). In contrast, myosin light chain 1 (MLC 1) and creatine kinase (CK) were over-expressed in the somatic muscle relative to the dental muscle. These results suggest that these two muscles have different energy sources and contractile properties and provide an initial representative map for comparative studies of muscle-protein expression in low craniates.

Sound production by a recoiling system in the pempheridae and terapontidae.

Sound-producing mechanisms in fishes are extraordinarily diversified. We report here original mechanisms of three species from two families: the pempherid Pempheris oualensis, and the terapontids Terapon jarbua and Pelates quadrilineatus. All sonic mechanisms are built on the same structures. The rostral part of the swimbladder is connected to a pair of large sonic muscles from the head whereas the posterior part is fused with bony widenings of vertebral bodies. Two bladder regions are separated by a stretchable fenestra that allows forward extension of the anterior bladder during muscle contraction. A recoiling apparatus runs between the inner face of the anterior swimbladder and a vertebral body expansion. The elastic nature of the recoiling apparatus supports its role in helping the swimbladder to recover its initial position during sonic muscle relaxation. This system should aid fast contraction (between 100 and 250Hz) of sonic muscles. There are many differences between species in terms of the swimbladder and its attachments to the vertebral column, muscle origins, and morphology of the recoiling apparatus. The recoiling apparatus found in the phylogenetically-related families (Glaucosomatidae, Pempheridae, Terapontidae) could indicate a new character within the Percomorpharia. J. Morphol. 277:717-724, 2016. © 2016 Wiley Periodicals, Inc.

Meiofaunal communities in a tropical seagrass bed and adjacent unvegetated sediments with note on sufficient sample size for determining local diversity indices.

BACKGROUND: Seagrass beds are highly diverse and productive marine habitats for many associated organisms in nearshore coastal waters. The differences in abundance, diversity, and community structure of benthic invertebrates between seagrass beds and adjacent unvegetated sediments have been stated, whereas most studies are primarily focused on macrofauna or based on a comparatively long distance, i.e., more than 10 m. The present study is designed to test if the community structures of meiofauna, especially the free-living nematodes, differ between seagrass beds and adjacent unvegetated sediments on a meter scale. RESULTS: There are 21 meiofaunal taxa and 63 nematode genera that have been identified from a tropical seagrass bedof Thalassia hemprichii inLudao, Taiwan. Although the compositions of higher meiofaunal taxa are undistinguished, according to correspondence analysis, the assemblages of nematode genera differ substantially between the seagrass bed and unvegetated sediments. Regarding the nematodes, approximately 50% of genera are restricted to the seagrass bed whereas 6% are restricted to unvegetated sediments, which indicate both habitats possessing distinct infaunas. The number of replicates for reasonable estimation of the local diversity index is calculated by the randomization technique. For local seagrass beds, only a single core is sufficient for reliably estimating meiofaunal diversity, but at least three cores or a sample size of 300 individuals is needed for the nematode community. CONCLUSIONS: Nematode assemblages provide more particular differences between seagrass and unvegetated habitats than meiofaunal communities on small spatial scales. Both seagrass beds and adjacent unvegetated sediments harbor specific meiofaunal communities, and hence, the conservation strategy for seagrass should also consider the peripheral bare area of seagrass beds.

Spatiotemporal variability and sound characterization in silver croaker Plagioscion squamosissimus (Sciaenidae) in the Central Amazon.

BACKGROUND: The fish family Sciaenidae has numerous species that produce sounds with superfast muscles that vibrate the swimbladder. These muscles form post embryonically and undergo seasonal hypertrophy-atrophy cycles. The family has been the focus of numerous passive acoustic studies to localize spatial and temporal occurrence of spawning aggregations. Fishes produce disturbance calls when hand-held, and males form aggregations in late afternoon and produce advertisement calls to attract females for mating. Previous studies on five continents have been confined to temperate species. Here we examine the calls of the silver croaker Plagioscion squamosissimus, a freshwater equatorial species, which experiences constant photoperiod, minimal temperature variation but seasonal changes in water depth and color, pH and conductivity. METHODS AND PRINCIPAL FINDINGS: Dissections indicate that sonic muscles are present exclusively in males and that muscles are thicker and redder during the mating season. Disturbance calls were recorded in hand-held fish during the low-water mating season and high-water period outside of the mating season. Advertisement calls were recorded from wild fish that formed aggregations in both periods but only during the mating season from fish in large cages. Disturbance calls consist of a series of short individual pulses in mature males. Advertisement calls start with single and paired pulses followed by greater amplitude multi-pulse bursts with higher peak frequencies than in disturbance calls. Advertisement-like calls also occur in aggregations during the off season, but bursts are shorter with fewer pulses. CONCLUSIONS AND SIGNIFICANCE: Silver croaker produce complex advertisement calls that vary in amplitude, number of cycles per burst and burst duration of their calls. Unlike temperate sciaenids, which only call during the spawning season, silver croaker produce advertisement calls in both seasons. Sonic muscles are thinner, and bursts are shorter than at the spawning peak, but males still produce complex calls outside of the mating season.