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FIG. 20 in An inventory of Bramble sharks Echinorhinus brucus (Bonnaterre, 1788) (Elasmobranchii, Echinorhinidae) in natural history collections worldwide for conservation status assessment

FIG. 20. — Echinorhinus brucus (Bonnaterre, 1788) in French (Nantes) collections (continuation): A-E, MHNN.Z.019419 (Entry 73).

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Vertebral morphology in the tail-whipping common thresher shark, Alopias vulpinus

Thresher sharks (Alopias spp.) are characterized by an elongated, scythe-like caudal fin that is used in tail-whipping, a behavior where the tail is thrown overhead to stun prey. Tail-whipping is performed via extreme dorsoventral bending of the vertebral column and is dramatically different from lateral oscillatory motion used for swimming. Previous work has examined thresher shark vertebral morphology and mechanical properties but in the context of swimming loads. Our goal was to assess centra morphometrics and microarchitecture for variations that may support extreme dorsoventral bending. We examined anterior and posterior body vertebrae from an embryo, 5 juvenile, and 4 adult thresher sharks using micro-computed tomography. We used principal component and landmark analyses to examine variables influencing vertebral morphology and mineral arrangement, respectively. We found that morphology and microstructure significantly varied across body regions and ontogeny. We hypothesize that anterior body vertebrae increase stability, while posterior body vertebrae support the caudal fin. Vertebral size and quantity of mineral structures (lamellae and nodes) increased across ontogeny, suggesting vertebrae adapt over development to support a larger body and tail. Based on our results, we hypothesize that thresher shark vertebrae vary in morphometrics and mineralization (amount and arrangement) supporting the mechanical needs for tail-whipping.

opencc-zeroDec 2023View details →

opencc-by-4.0Dec 2023View details →

Data for: Understanding consumers to inform market interventions for Singapore's shark fin trade

<ol> <li>Sharks, rays and their cartilaginous relatives (Class Chondricthyes, herein 'sharks') are amongst the world's most threatened species groups, primarily due to overfishing, which in turn is driven by complex market forces including demand for fins. Understanding the high-value shark fin market is a global priority for conserving shark and rays, yet the preferences of shark fin consumers are not well understood. This gap hinders the design of evidence-based consumer-focused conservation interventions. </li> <li>Using an online discrete choice experiment, we explored preferences for price, quality, size, menu types (as a proxy for exclusivity) and source of fins (with varying degrees of sustainability) among 300 shark fin consumers in Singapore: a global entrepot for shark fin trade. </li> <li>Overall, consumers preferred lower-priuced fins sourced from responsible fisheries or produced using novel lab-cultured techniques. We also identified four consumer segments, each with distinct psychographics characteristics and consumption behaviors. </li> <li>These preferences and profiles could be leveraged to inform new regulatory and market-based interventions regarding the sale and consumption of shark fins, and incentivize responsible fisheries and lab-cultured innovation for delivering conservation and sustainability goals. </li> <li>In addition, message framing around health benefits, shark endangerment and counterfeiting could reinforce existing beliefs amongst consumers in Singapore and drive behavioral shifts to ensure that market demand remains within the limits of sustainable supply. </li> </ol> This dataset includes all the responses collected from the online discrete choice experiment which was implemented by a market survey company, as well as the goodness-of-fit chi-square analyses. These data were also used to plot the figures in the manuscript and the Supplemental Information. Password for excel sheet titled 'Final CEOE data' is 35433. Please refer to the published manuscript for more detailed information. The authors received financial support from Silverstrand Capital awarded to Wildlife Conservation Society for the research, authorship, and publication of this work.

Figure 5 in Species Composition, Diversity and Length Frequency of By-Catch Sharks from the Syrian Coast

Figure 5. Geographic distribution of possible nursery areas for three species (H. griseus; +, C. plumbeus; ×, M. mustelus; *, black circles; main cities) in Syrian marine waters.

Figure1 in Species Composition, Diversity and Length Frequency of By-Catch Sharks from the Syrian Coast

Figure1. Changes of diversity indices seasonally for by-catch sharks: (a); diversity index H, (b); qualitative richness factor D, (c); evenness factor

Figure 3 in Species Composition, Diversity and Length Frequency of By-Catch Sharks from the Syrian Coast

Figure 3. Size (TL) variations of abundant and common of by-catch sharks per season off Syria coast. Males (gray), females (white): (a); H. griseus,(b); H. perlo, (c); C. plumbeus, (d); M. mustelus (e); G. melastomus, (f); S. blainvillei, (g); C. granulosus, (h); C. uyato

Figure 4 in Species Composition, Diversity and Length Frequency of By-Catch Sharks from the Syrian Coast

Figure 4. Total length (TL) frequency distributions (percent of species catch) of the abundant and common bycatch sharks off Syrian coast. Males (black), females (white). Vertical lines indicate maturity size of males (sporadic) and females (continuous) following literature: (a); H. griseus,(b); H. perlo, (c); C. plumbeus, (d); M. mustelus (e); G. melastomus, (f); S. blainvillei, (g); C. granulosus, (h); C. uyato

Figure 2 in Species Composition, Diversity and Length Frequency of By-Catch Sharks from the Syrian Coast

Figure 2. Changes of caught specimens number per season; (a) H. griseus,(b); H. perlo, (c); C. plumbeus, (d); M. mustelus (e); G. melastomus, (f); S. blainvillei, (g); C. moluccensis, (h); C. granulosus

Figure 2 in The dentition of the extinct megamouth shark, (Lamniformes: Megachasmidae), from southern California, USA, based on geometric morphometrics

Figure 2. Homologous landmark (numbered black or white circles) and semi-homologous landmark (red circles with asterisk [*] connected by red lines) on tooth samples of Megachasma applegatei (A), M. pelagios (B), and Odontaspis ferox (C) for principal component analysis (not to scale). Seven homologous landmarks: 1, the crown apex, 2 and 3, right- and left-most extremities of the crown; 4, apical-most point around the middle of the crown base; 5 and 6, basal extremity of each of the two root lobes; and 7, apical-most point of the basal root concavity.

Figure 3. A in The dentition of the extinct megamouth shark, (Lamniformes: Megachasmidae), from southern California, USA, based on geometric morphometrics

Figure 3. A. Scatter plot diagram showing principal component analysis of 207 teeth of Megachasma applegatei (black plots) compared with all 178 teeth of extant M. pelagios (red plots), and all 78 teeth of extant Odontaspis ferox separated into tooth types using different colors (symphysial teeth = green; anterior teeth = dark blue; intermediate teeth = purple; lateral teeth = brown). B. Scatter plot diagram exclusively of M. applegatei, showing examples of actual specimens (not to scale) represented by certain plots (illustrated teeth: LACM 9883, 150907, 155340, 155348, 155357, 155373, 155393, 155424, 155434, 155456, 155563, 155622, 155630, 155651, 155653, 155694, and 155700). C. Scatter plot diagram exclusively of M. pelagios, showing examples of actual specimens (not to scale: see Fig. 1C, D) represented by certain plots. D. Scatter plot diagram exclusively of O. ferox, showing examples of actual specimens (not to scale: see Fig. 1F) represented by certain plots. Asterisk (*): on axes in B and C = PC1 and PC2 originally labeled inversely by the software (see text for detail); by photograph of teeth in C-D = Upper teeth.

Figure 1. A in The dentition of the extinct megamouth shark, (Lamniformes: Megachasmidae), from southern California, USA, based on geometric morphometrics

Figure 1. A. Generalized consensus tree of extant lamniform families on the basis of molecular-based phylogenetic studies, highlighting Megachasmidae in bold (see Stone and Shimada 2019, fig. 6, and references therein). B. Extant megamouth shark, Megachasma pelagios (after Compagno 1984). C, D. Right upper (C) and right lower (D) teeth of extant M. pelagios (BPBM 22730, 446 cm TL, male) in (from top row to bottom row) lingual, labial, mesial, apical, and basal views, showing strong tendency towards homodonty. E. Extant smalltooth sand tiger, Odontaspis ferox (after Compagno 1984). F. Left upper and left lower dental series of extant O. ferox (BPBM 9335, 297(?) cm TL, male(?)) showing representative 'lamnoid tooth pattern' (A or a = anterior teeth; I or i = intermediate tooth; L or l = lateral tooth; S or s = symphysial tooth). Scale bars: B and E = 50 cm; C, D, F = 5 mm

Figure 4 in The dentition of the extinct megamouth shark, (Lamniformes: Megachasmidae), from southern California, USA, based on geometric morphometrics

Figure 4. Three reconstructed dentitions of Megachasma applegatei under three different assumptions (see text for detail). A. Artificial dentition based on Odontaspis ferox as a model. B. Artificial dentition depicted as intermediate between O. ferox and M. pelagios. C. Artificial dentition based on M. pelagios as a model. Scale bar = 5 mm (note: each scale bar applies to each respective dentition consisting of teeth with digitally adjusted sizes [see text]).

opencc-by-4.0Apr 2019View details →

FIGURE 2 in Evidence for dynamic resource partitioning between two sympatric reef shark species within the British Indian Ocean Territory

FIGURE 2 (a) Maximum likelihood standard ellipse areas (, 40% of the data) for isotopes δ13C v. δ15N in fin, (b) muscle, (c) red blood cell, (d) plasma and for isotope δ34S v. δ15C (e) and δ15N (f) of Carcharhinus amblyrhynchos () and Carcharhinus albimarginatus (). Convex hulls () are drawn between the centers of each group. Overlapping values, if present, are the proportion of overlapping area of the two ellipses. Potential competitor–prey teleost data are shown () with associated error bars (± 1 SD). Ellipses for red blood cell and plasma presented for reference but represent small sample sizes (<10) and therefore come with lower confidence

opencc-by-4.0Apr 2019View details →

FIGURE 1 in Evidence for dynamic resource partitioning between two sympatric reef shark species within the British Indian Ocean Territory

FIGURE 1 Bayesian isotope mixing models were used to determine the extent that Carcharhinus amblyrhynchos and Carcharhinus albimarginatus were reliant on reef (blue) or pelagic (red) resources. End members were set as the most δ13C depleted (pelagic) and most δ13C enriched (reef) of the teleosts sampled (trevally (Carangidae) for reef, tuna (Scombridae) for pelagic). Posterior probability distributions indicate model predictions of reliance on a given source with higher values indicating greater reliance

FIGURE 6 in A megatoothed shark (Carcharocles angustidens) nursery in the Oligocene Charleston Embayment, South Carolina, USA

FIGURE 6. Histogram showing range of body length estimates from A) the McKewn subdivision sample (n=32), B) the Chandler Bridge excavation sample (n=95), and C) combined samples from the Chandler Bridge Formation (McKewn subdivision and Chandler Bridge excavation; n=127).

FIGURE 4 in A megatoothed shark (Carcharocles angustidens) nursery in the Oligocene Charleston Embayment, South Carolina, USA

FIGURE 4. Teeth of Carcharocles angustidens from the Chandler Bridge Formation (late Oligocene), from the Chandler Bridge excavation sample, in anatomical orientation (e.g., crown downwards for upper teeth); labial on left, lingual on right in all cases. All specimens shown to scale.

FIGURE 3 in A megatoothed shark (Carcharocles angustidens) nursery in the Oligocene Charleston Embayment, South Carolina, USA

FIGURE 3. Teeth of Carcharocles angustidens from the Chandler Bridge Formation (late Oligocene), from the McKewn subdivision sample (top, CCNHM specimens) and part of the Chandler Bridge excavation sample (bottom, ChM specimens). Teeth shown in anatomical orientation (e.g., crown downwards for upper teeth); labial on left, lingual on right in all cases. All specimens shown to scale.

FIGURE 2 in A megatoothed shark (Carcharocles angustidens) nursery in the Oligocene Charleston Embayment, South Carolina, USA

FIGURE 2. The largest available specimens (crown height>75 mm) of Carcharocles angustidens, in labial view (left) and lingual view (right).

FIGURE 1 in A megatoothed shark (Carcharocles angustidens) nursery in the Oligocene Charleston Embayment, South Carolina, USA

FIGURE 1. Generalized geology and stratigraphy of Oligocene marine strata in the vicinity of Ladson and Summerville, South Carolina, USA. A) Map of South Carolina showing Charleston. B) Map of Charleston showing the extent of Oligocene marine rocks; star denotes the location of the McKewn subdivision and Chandler Bridge excavation localities. C) Stratigraphic column of Oligocene marine rocks and overlying deposits as exposed in stormwater pond excavations at the McKewn Subdivision locality near Ladson, South Carolina. Modified from Fallon and Boessenecker (2020).

FIGURE 5 in A megatoothed shark (Carcharocles angustidens) nursery in the Oligocene Charleston Embayment, South Carolina, USA

FIGURE 5. Teeth of Carcharocles angustidens from the Ashley Formation (early Oligocene), from the McKewn subdivision sample, in anatomical orientation (e.g., crown downwards for upper teeth); labial on left, lingual on right in all cases. All specimens shown to scale.