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The habitat preferences of many reef fishes are well established, but the use of space within these habitats by non‐site‐attached species is poorly studied. The authors examined the space use of a functionally important mesopredator, graysby (Cephalopholis cruentata), on six patch reefs in the Florida Keys. A 1 m2‐scale grid was constructed on each reef and 16 individual C. cruentata were tracked diurnally in situ to identify space use. At the patch reef scale, larger C. cruentata were more active and had larger observed home ranges, although home ranges were also affected by fish density and the abundances of prey and predators. The total time in each 1 m2 grid cell was regressed against a range of fine‐scale biotic variables, including multiple variables derived from structure‐from‐motion three‐dimensional digital reconstructions of each reef. Nonetheless, time in grid cells (preferred microhabitats) was only significantly positively correlated with the height of carbonate structures, likely because the cavities they enclose are particularly suitable for predator avoidance, resting and ambushing prey. The ongoing flattening of reefs in the region caused by negative carbonate budgets is thus likely to have significant effects on the abundance and space use of C. cruentata. In addition to examining spatial patterns, we analysed C. cruentata waiting times in each grid cell before moving. These times were best approximated by a truncated power‐law (heavy‐tailed) distribution, indicating a "bursty" pattern of relatively long periods of inactivity interspersed with multiple periods of activity. Such a pattern has previously been identified in a range of temperate ambush predators, and the authors extend this move‐wait behaviour, which may optimize foraging success, to a reef fish for the first time. Understanding how C. cruentata uses space and time is critical to fully identify their functional role and better predict the implications of fishing and loss of reef structure. [ABSTRACT FROM AUTHOR]

Abstract Aurantiochytrium strain BL10 is rich in highly unsaturated fatty acids (HUFAs), particularly docosahexaenoic acid (DHA). Previous research has shown that adding 2% of dry BL10 powder to increase the DHA content of feed for orange-spotted grouper (Epinephelus coioides) does not benefit growth but can significantly reduce size discrepancies between individuals and thereby potentially decrease the chance of cannibalism. To understand whether a 2% BL10 supplement can really reduce the cannibalism rates of E. coioides , whether increasing the BL10 dosage can reduce the cannibalism rates of E. coioides even further, and how the BL10 supplements affect cannibalistic behavior, we produced four isonitrogenous and isolipidic experimental diets dosed with different weight percentages (0, 2, 4, 6%) BL10 meal and fed it to E. coioides fingerlings (total length 3.8 ± 0.3 cm) for two weeks. During the feeding period, cannibalism in the experiment groups were observed. After the feeding period, we analyzed the brain fatty acid composition, brain 5-hydroxytryptamine (5-HT) levels, and serum cortisol levels in the experiment groups and used regression analysis to examine the relationships among these biochemical variants and cannibalism rates. The results indicate that 2–6% BL10 supplements, particularly 2% BL10 supplement, could significantly reduce the cannibalism rates of E. coioides. The BL10 supplements increased the proportions and contents of HUFAs in the brains of E. coioides , increased brain 5-HT levels, and reduced serum cortisol levels. The results of univariate linear regression indicated that the serum cortisol level exhibited a significant negative correlation with brain HUFA content, particularly arachidonic acid (ArA). Whereas, brain 5-HT was positively correlated with the ratio of n-3/n-6 fatty acids in the brain. Subsequent multivariate linear regression demonstrated that cannibalism is affected by serum cortisol, brain 5-HT levels and their interaction. Our results provide new insight into the physiological regulation mechanisms behind the cannibalistic behavior of teleost and provide a feasible solution at the same time. Highlights • BL10 supplement could significantly reduce the cannibalism rates of orange-spotted groupers. • BL10 supplement altered the contents of HUFAs and 5-HT in brain and cortisol levels in serum of orange-spotted groupers. • Serum cortisol level was negatively correlated with brain HUFA content. • Brain 5-HT was positively correlated with the ratio of n-3/n-6 fatty acids in the brain. • The cannibalism rate of orange-spotted grouper is associated with both serum cortisol and brain 5-HT levels in the grouper school. [ABSTRACT FROM AUTHOR]

Recent studies reported the introduction of non-native species on the Brazilian coast. In this contribution, we provide the first record of Cephalopholis taeniops (Valenciennes 1828) in the western South Atlantic, based on a specimen captured off the Ilhas Cagarras, Rio de Janeiro, Brazil, and discuss the potential agents for its introduction. While this single specimen was collected in 2006 in a well-known locality, no other specimen has been captured since. [ABSTRACT FROM AUTHOR]

Until recently, eleven species of the genus Cephalopholis (Serranidae) have been recorded from Taiwanese waters. Although Cephalopholis cyanostigma (Valenciennes, 1828) was previously known from the western Pacific Ocean north to Philippines, no records have been reported from Taiwan. The main objective of this study was to document the presence of C. cyanostigma in waters of Taiwan. Three specimens (169.9-189.7 mm standard length) of C. cyanostigma were collected from southern Taiwan in 2017. The morphology and fresh coloration of the collected specimens are herein described. The majority of morphological characters are consistent with those representing previous descriptions of Cephalopholis cyanostigma: dorsal-fin soft rays 16; anal-fin soft rays 8; longitudinal scale series 93; caudal fin rounded; body colour reddish brown with small darkedged pale blue spots on head and body; body with pale spots larger than pupil form irregular bars; pectoral fin nearly all orange with dark-edged pale blue spots. The grouper specimens from southern Taiwan are identified as Cephalopholis cyanostigma. The presently reported specimens represent the first record for Taiwan, and their finding constitutes the northernmost record of this species. [ABSTRACT FROM AUTHOR]

Graysby (Cephalophilis cruentata) (n = 1308) collected from the southeastern United States Atlantic coast from 2001 to 2016 were aged using sectioned sagittal otoliths. Opaque zones formed February to June (peaking in April). Ages ranged from 2 to 21 years, and the largest fish measured 453 mm TL. Growth morph analysis revealed two regionally distinct growth trajectories: von Bertalanffy growth equations were Lt = 388 (1 − e−0.12(t+5.73)) for fish from North Carolina through southeast Florida (northern region), and Lt = 267 (1 − e−0.17(t+6.20)) for fish from the Florida Keys (southern region). When growth was re-estimated using a fixed t0 value of −0.75 to estimate for smaller fish, growth equations were Lt = 349 (1 − e−0.26(t+0.75)) and Lt = 250 (1 − e−0.43(t+0.75)) for fish from the northern and southern regions, respectively. The age-invariant estimate of natural mortality was M = 0.30 for all fish, while age-specific estimates ranged 0.88−0.28 y−1 for fish aged 1−21 from the northern region and 0.89−0.47 y−1 for fish aged 1−15 from the southern region. This study presents the first comprehensive analysis of life-history parameters for graysby from the Atlantic waters off the southeastern United States, including specimens from both recreational and commercial fisheries.

Changes in innate immunity parameters and epinecidin mRNA transcript levels were examined to characterize the non-specific immune response of E. coioides to pathogenic V. harveyi JML1 isolated from affected cage-cultured fish. After fish had been injected with bacteria at a dose causing 30% mortality, blood and tissue samples were collected at 0, 6, 12, 24, 48, 72, 96, 120, and 240 h post-infection (hpi) for assessment of indices such as the oxidative burst (OB) and phagocytic index (PI) of head kidney cells, and lysozyme activity (LYS) and total immunoglobulin (Total Ig) levels of the plasma. The epinecidin mRNA transcript levels (EGE) from skin, gills, liver, kidney, and spleen tissues were also determined by gel-based RT-PCR. Lastly, daily mortality (DM), liver total bacterial load (TBC), and presumptive Vibrio count (TVC) were monitored up to 240 hpi. The results revealed that bacteria proliferated rapidly in fish tissue, reaching peak densities at 24 hpi for both TBC and TVC but was on a downward trend thereafter. The pattern in fish mortality closely correlated with TBC and TVC. Total Ig, OB, and PI in E. coioides were suppressed in the early part of infection when V. harveyi load was high but recovered and later increased as bacterial density declined. LYS and EGE were consistently high and their activities were not hampered by bacterial infection. The study demonstrated that V. harveyi JML1 interacts with E. coioides by transiently inhibiting some immune parameters resulting in mortalities. However, consistently high LYS, upregulated EGE, and resurgent PI, OB and Total Ig conferred resistance and subsequent recovery in the fish. The study provides new insights on the interaction between E. coioides and V. harveyi JML1 that can aid in formulating health management strategies for groupers. Further studies on prophylactic interventions to enhance the innate immune response in grouper during infection with V. harveyi JML1 are suggested. [ABSTRACT FROM AUTHOR]

Gonadotropin-inhibitory hormone (GnIH) and its receptor (GnIHR) play an important role in reproduction regulation in birds, mammals and some teleost species. In protogynous hermaphroditic orange-spotted grouper ( Epinephelus coioides ), the GnIH/GnIHR signaling pathway and its reproductive function have not been addressed yet. In this study, GnIH and GnIHR in orange-spotted grouper were characterized. gGnIH possessed three putative peptides (gGnIH-I, -II, -III), while gGnIHR showed the characteristics of G protein-coupled receptor and was clustered with GPR147. Functional assays demonstrated that three synthetic gGnIH peptides significantly decreased the forskolin-induced CRE promoter activity, but only gGnIH-I could significantly decrease SRE promoter activity in COS-7 cells transfected with gGnIHR . During the process of ovarian differentiation and development, gGnIH mRNA level in hypothalamus was low at the gonadal primordium stage with gonia, then increased significantly at the early differentiated gonad with primary growth oocytes, while decreased significantly at the developing gonads with cortical-alveolus and vitellogenic stage oocytes. During MT-induced sex reversal, gGnIH mRNA level in hypothalamus increased significantly when the fish completely reversed from female to male. However, gGnIHR mRNA level in pituitary decreased significantly in intersex and completely reversed male fish. Intraperitoneal injection (i.p.) of three gGnIH peptides significantly decreased GnRH1 mRNA levels in hypothalamus, and gGnIH-II significantly inhibited synthesis of LHβ in pituitary. In summary, we firstly identified the GnIH / GnIHR signal in protogynous orange-spotted grouper, which might be involved in the regulation of the reproductive function of sex differentiation, gonadal development and sex reversal via regulating the synthesis of both GnRH and GtH. [ABSTRACT FROM AUTHOR]

Few studies have documented the activity patterns of both predators and their common prey over 24 h diel cycles. This study documents the temporal periodicity of two common resident predators of juvenile reef fishes, Cephalopholis cyanostigma (rockcod) and Pseudochromis fuscus (dottyback) and compares these to the activity and foraging pattern of a common prey species, juvenile Pomacentrus moluccensis (lemon damselfish). Detailed observations of activity in the field and using 24 h infrared video in the laboratory revealed that the two predators had very different activity patterns. C. cyanostigma was active over the whole 24 h period, with a peak in feeding strikes at dusk and increased activity at both dawn and dusk, while P. fuscus was not active at night and had its highest strike rates at midday. The activity and foraging pattern of P. moluccensis directly opposes that of C. cyanostigma with individuals reducing strike rate and intraspecific aggression at both dawn and dusk, and reducing distance from shelter and boldness at dusk only. Juveniles examined were just outside the size-selection window of P. fuscus. We suggest that the relatively predictable diel behaviour of coral reef predators results from physiological factors such as visual sensory abilities, circadian rhythmicity, variation in hunting profitability, and predation risk at different times of the day. Our study suggests that the diel periodicity of P. moluccensis behaviour may represent a response to increased predation risk at times when both the ability to efficiently capture food and visually detect predators is reduced. [ABSTRACT FROM AUTHOR]

Pelagic larval duration ( PLD) has been hypothesized to be the primary predictor of connectivity in marine fishes; however, few studies have examined the effects that adult reproductive behaviour may have on realized dispersal. We assessed gene flow (connectivity) by documenting variation in microsatellites and mitochondrial DNA sequences in two protogynous species of groupers, the aggregate spawning red hind, Epinephelus guttatus, and the single-male, harem-spawning coney, Cephalopholis fulva, to ask whether reproductive strategy affects connectivity. Samples of both species were obtained from waters off three islands ( Puerto Rico, St. Thomas and St. Croix) in the Caribbean Sea. Despite the notion that aggregate spawning of red hind may facilitate larval retention, stronger signals of population structure were detected in the harem-spawning coney. Heterogeneity and/or inferred barriers, based on microsatellites, involved St. Croix (red hind and coney) and the west coast of Puerto Rico (coney). Heterogeneity and/or inferred barriers, based on mitochondrial DNA, involved St. Croix (coney only). Genetic divergence in both species was stronger for microsatellites than for mitochondrial DNA, suggesting sex-biased dispersal in both species. Long-term migration rates, based on microsatellites, indicated asymmetric gene flow for both species in the same direction as mean surface currents in the region. Red hind had higher levels of variation in microsatellites and lower levels of variation in mitochondrial DNA. Long-term effective size and effective number of breeders were greater for red hind; estimates of θ f, a proxy for long-term effective female size, were the same in both species. Patterns of gene flow in both species appear to stem in part from shared aspects of larval and adult biology, local bathymetry and surface current patterns. Differences in connectivity and levels of genetic variation between the species, however, likely stem from differences in behaviour related to reproductive strategy. [ABSTRACT FROM AUTHOR]

The reproductive biology of the Panama graysby Cephalopholis panamensis was studied from collections and behavioural observations made in the Gulf of California from 2001 to 2006. Histological examinations, particularly the identification of gonads undergoing sexual transition, confirmed a protogynous hermaphroditic sexual pattern. The population structure and mating behaviour provided further support for protogyny. Size and age distributions by sex were bimodal, with males larger and older than females and sex ratios biased towards females. Mating groups consisted of a large male and several smaller females, and courtship occurred in pairs during the evening. Results on spawning periodicity and seasonality were incomplete, but histological data, monthly gonado-somatic indices ( IG) and behavioural observations suggest that adults spawned around the full moon from May to September. Certain aspects of their reproductive biology ( e.g. protogyny and low egg production) indicate that C. panamensis is particularly vulnerable to fishing and would benefit from a management policy in Mexico. [ABSTRACT FROM AUTHOR]

The record of several individuals of the African hind Cephalopholis taeniops from Lampedusa Island (Italy) is here reported, with discussion on the biogeographical importance of the Sicily channel as a crossroad for exotic fish of Atlantic and Indo-pacific origin. [ABSTRACT FROM AUTHOR]

The article examines the relative effects of a less-targeted piscivore and large-bodied piscivore on the enlisting of coral-reef fishes. It highlights the use of Nassau grouper Epinephelus striatus and coney Cephalopholis fulva for the influence of groupers on the abundance of their prey. Furthermore, it discusses the effects of the individual species on the community structure and abundance of the prey. Moreover, it outlines the significant impact of the findings to the direct and indirect effects of fishing.

Epinecidin-1 is an antimicrobial peptide and plays a vital role in protecting fish against pathogenic infection. As a mimic of a grouper epinecidin-1 peptide, it has tertiary structures that closely resemble those of pleurocidin found in the winter flounder ( Pleuronectes americanus). The tissue-specific, lipopolysaccharide (LPS)–stimulation-specific, and poly(I):poly(C)-stimulation-specific expressions of the grouper ( Epinephelus coioides) epinecidin-1 antimicrobial peptide were determined using a comparative reverse-transcription polymerase chain reaction. Results of the tissue distribution analysis revealed high levels of epinecidin-1 messenger RNA (mRNA) in the head kidneys, intestines, and skin. Expression of epinecidin-1 mRNA was dose-dependently stimulated by both LPS and poly(I):poly(C). Immunohistochemical analysis with the polyclonal antiserum of a grouper epinecidin-1 peptide (rabbit polyclonal antibody) showed that the peptide was localized with the epinecidin-1 antibody in the gills and intestines. Two synthetic peptides of the grouper epinecidin-1 peptide (g-ple 22–51 and g-ple 22–42) and one winter flounder pleurocidin as a control exhibited high antimicrobial activities against gram-negative or gram-positive bacteria. In addition, peptide treatment was effective in promoting a significant increase in fish survival after the injection of Vibrio vulnificus in tilapia ( Oreochromis mossambicus) and grouper. These results are relevant to the design of prophylactic and therapeutic strategies to counter bacterial infections, especially for preventing or ameliorating immune defects in fish during bacterial infections. [ABSTRACT FROM AUTHOR]

Using the same methodology and identical sites, we repeat a study dating from 1973 and quantify cover of hard coral species, soft corals, sponges, hard substratum and soft substratum, and density of a commercially important reef fish species, the graysby Cephalopholis cruentata, along a depth-gradient of 3–36 m on the coral reefs of Curaçao. The objective was to determine the multi-decade change in benthic coral reef cover and structural complexity, and their effect on densities of an associated reef fish species. Total hard coral cover decreased on average from 52% in 1973 to 22% in 2003, representing a relative decline of 58%. During this time span, the cover of hard substratum increased considerably (from 11 to 58%), as did that of soft corals (from 0.1 to 2.2%), whereas the cover of sponges showed no significant change. Relative decline of hard coral cover and of reef complexity was greatest in shallow waters (near the coast), which is indicative of a combination of anthropogenic influences from shore and recent storm damage. Cover of main reef builder coral species ( Agaricia spp., Siderastrea siderea, Montastrea annularis) decreased more than that of other species, and resulted in a significant decrease in reef complexity. Although density of C. cruentata was highly correlated to cover of Montastrea and A garicia in 1973, the loss of coral cover did not show any effect on the total density of C. cruentata in 2003. However, C. cruentata showed a clear shift in density distribution from shallow water in 1973 to deep water in 2003. It can be concluded that the reefs of Curaçao have degraded considerably in the last three decades, but that this has had no major effect on the population size of one commercially important coral-associated fish species. [ABSTRACT FROM AUTHOR]

Home range size and shape, and within home range movement patterns were determined from 10 adult graysby Cephalopholis cruentata implanted with acoustic transmitters on two reefs within the Soufriere Marine Management Area, St Lucia. The mean home range area was 2120 m2(range 1200 to 4000 m2) and non-circular in shape. All fish demonstrated a clear preference for a specific area in their home range where, on average, 72·9% of an individuals position were located. Time spent in this favoured area was correlated with reef complexity. Fish with greater activity and displacement possessed a larger home range. Activity and displacement were higher by night than by day, and consistent with this, fish spent less time in the preferred area of their home range by night than by day. Tagged individuals demonstrated a strong tendency to avoid sand habitat present at reserve boundaries. [ABSTRACT FROM AUTHOR]

Summary: Signals transmit information to receivers about sender attributes, increase the fitness of both parties, and are selected for in cooperative interactions between species to reduce conflict []. Marine cleaning interactions are known for stereotyped behaviors [] that likely serve as signals. For example, “dancing” and “tactile dancing” in cleaner fish may serve to advertise cleaning services to client fish [] and manipulate client behavior [], respectively. Cleaner shrimp clean fish [], yet are cryptic in comparison to cleaner fish. Signals, therefore, are likely essential for cleaner shrimp to attract clients. Here, we show that the yellow-beaked cleaner shrimp [] Urocaridella sp. c [] uses a stereotypical side-to-side movement, or “rocking dance,” while approaching potential client fish in the water column. This dance was followed by a cleaning interaction with the client 100% of the time. Hungry cleaner shrimp, which are more willing to clean than satiated ones [], spent more time rocking and in closer proximity to clients Cephalopholis cyanostigma than satiated ones, and when given a choice, clients preferred hungry, rocking shrimp. The rocking dance therefore influenced client behavior and, thus, appears to function as a signal to advertise the presence of cleaner shrimp to potential clients. [Copyright &y& Elsevier]

Adult sex change and juvenile sexual differentiation in the protogynous epinepheline Cephalopholis boenak were demonstrated in captivity to be influenced by social factors. Adult sex change in C. boenak occurred in two directions, female to male and male to female. The presence or absence of a larger male plays an important role in adult female sex change; female(s) did not change sex in the presence of a larger male, but sex change occurred after the removal of the larger males in the same social groups. In male pairs, either the larger or the smaller male changed sex. Male to female sex change has not been reported previously in Cephalopholis, and only rarely in epinephelines. This is the first report of direct male sexual differentiation from juveniles (i.e. primary male development), through manipulating the number of juveniles, in a protogynous epinepheline. All isolated, single, juveniles differentiated directly as males, and male to female sex ratios did not differ significantly from 1:1 in all experimental social groups of two to four juveniles. Differentiating males grew significantly faster than differentiating females and undifferentiated juveniles during the 57-week experimental period. The role of growth rate in sex determination in C. boenak is not known but clearly plays a part in juvenile sexual differentiation and merits further investigation. Social factors influencing bi-directional adult sex change and juvenile sexual differentiation are a reflection of plasticity of sexual expression in C. boenak, in particular, and the Serranidae in general. [ABSTRACT FROM AUTHOR]

Early gonadal development of the protogynous epinepheline,Cephalopholis boenak, was examined histologically in 289 specimens with standard length( LS) of 42–130 mm, collected from May 2000 to April 2002 in Hong Kong waters, to determine male developmental pathways and establish its sexual pattern. All juvenile gonads developed an ovarian lumen with primary-growth stage oocytes and scattered spermatogenic tissue prior to sexual differentiation and first sexual maturation. From this bisexual phase containing both female and male tissues, some gonads differentiated as ovaries with further oocyte growth to cortical-alveolus and vitellogenic stages, the rest differentiated as testes with the proliferation of spermatogenic tissue and the formation of a sperm sinus. All testes retained the lumen and primary-growth stage oocytes, and sperm sinuses ran within the gonad wall. Unlike most protogynous species, among functional males it was impossible to distinguish those resulting from juveniles through sexual differentiation( i.e. primary male) from those resulting from functional females through sex change( i.e. secondary male) based solely on testicular morphology. A proportion-spermatogenic-tissue index( IST) was, therefore, developed and determined to be a reliable quantitative indicator for distinguishing differentiating, primary males before a sperm sinus was evident, from differentiating females during sexual differentiation. Since sexually transitional specimens with the concominant appearance of degenerating vitellogenic, or later, stage oocytes and spermatogenic tissue in the gonads were previously noted from Hong Kong, diandric, protogynous hermaphroditism is confirmed inC. boenak. For species, such as this and other epinephelines, in which all males have the same testicular morphology, a complete analysis of a wide range of body sizes from juveniles to adults is necessary for understanding male developmental pathways, and determining sexual pattern. [ABSTRACT FROM AUTHOR]

Despite the potential importance of predation as a process structuring coral reef fish communities, few studies have examined how the diet of piscivorous fish responds to fluctuations in the abundance of their prey. This study focused on two species of rock-cod, Cephalopholis cyanostigma (Valenciennes, 1828) and Cephalopholis boenak (Bloch, 1790) (Serranidae), and monitored their diet in two different habitats (patch and contiguous reef) at Lizard Island on the northern Great Barrier Reef, Australia, over a 2-year period. The abundance of the rock-cods and the abundance and family composition of their prey were monitored at the same time. Dietary information was largely collected from regurgitated samples, which represented approximately 60% of the prey consumed and were unbiased in composition. A laboratory experiment showed that fish were digested approximately four times faster than crustaceans, leading to gross overestimation of the importance of crustaceans in the diet. When this was taken into account fish were found to make up over 90% of the diet of both species. Prey fish of the family Apogonidae, followed by Pomacentridae and Clupeidae, dominated the diet of both species of rock-cod. The interacting effect of fluctuations in prey abundance and patterns of prey selection caused dietary composition to vary both temporally and spatially. Mid-water schooling prey belonging to the families Clupeidae and to a lesser extent Caesionidae were selected for over other families. In the absence of these types of prey, apogonids were selected for over the more reef-associated pomacentrids. A laboratory experiment supported the hypothesis that such patterns were mainly due to prey behaviour. Feeding rates of both species of rock-cod were much higher in summer than in winter, and in summer they concentrated on small recruit sized fish. However, there was little variation in feeding rates between habitats, despite apparent differences in prey abundance. In summary, our observations of how the feeding ecology of predatory fish responded to variation in prey abundance provide potential mechanisms for how predation may affect the community structure of coral reef fishes. [Copyright &y& Elsevier]

Discusses evidence of protogynous hermaphroditism in the darkfin hind Cephalospholis urodeta at Iriomote Island, southern Japan. Evaluation of gonads; Stages of germ cells; Photomicrographs of sections from Cephalopholis urodeta gonads.

We presented the complete mitochondrial genome of theEpinephelus corallicolain this study. The mitochondrial genome is 16,647 bp long and consists of 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and a control region. The gene order and composition ofEpinephelus corallicolamitochondrial genome was similar to that of most other vertebrates. The nucleotide compositions of the light strand are 26.60% of A, 15.89% of C, 28.66% of T and 28.85% of G. With the exception of the NADH dehydrogenase subunit 6 (ND6) and eight tRNA genes, all other mitochondrial genes are encoded on the heavy strand. [ABSTRACT FROM AUTHOR]