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Drilled holes on Clypeaster rosaceus (Inflated Sea Biscuit) by the radula of Cassis tuberosa (King Helmet) found in East Bay, South Caicos, Turks and Caicos Islands.
Source publication
Cassis tuberosa (King Helmet) is a large predatory gastropod found throughout
the Central Western Atlantic region. We examined a relatively undisturbed population of
King Helmets within a shallow bay in South Caicos, Turks and Caicos Islands, in order to
develop additional knowledge regarding this potentially threatened species. The majority
(74%)...
Context in source publication
Context 1
... percent of King Helmets were found in the process of consuming prey (n = 25), the majority (92%) of which were Inflated Sea Biscuits, with mean test length of 90.9 mm (± 3.6 sd) and a range of 85-97 mm. Inflated Sea Biscuits were found underneath King Helmets whole, with holes drilled (Fig. 4), in seg- ments, or crushed. West Indian Sea Eggs and Six-keyhole Sand Dollars were also observed being consumed. All three Flame Helmets (shell lengths: 194, 151, 136 mm) were also observed preying on Inflated Sea ...
Citations
... No existen estudios de la especie en Colombia; sin embargo, un estudio sobre distribución y abundancia de caracoles en general en La Guajira reportó densidades de 0,8 ± 4,4 ind/ha, en un área comprendida entre las poblaciones de Riohacha y Camarones (Nieto-Bernal et al. 2013). El valor es bajo comparado con las densidades reportadas en áreas de pastos marinos sin presión de pesca en diferentes localidades (hasta 15,8 ind/ha), pero similar a los valores reportados en sitios donde se extrae la especie (Tewfik y Scheuer 2013). ...
... Se ha sugerido que los bancos de macroalgas serían un sustrato importante para el desove de la especie (Dias y Mota 2015). Son depredadores carnívoros oportunistas que se alimentan exclusivamente de equinoideos, utilizando las especies presa más abundantes (Tewfik y Scheuer 2013). Algunas presas frecuentes del casco real son Diadema antillarum, Echinometra lucunter, Lytechinus variegatus, y Tripneustes ventricosus, y en ocasiones los dólares de mar Mellita quinquiesperforata y Leodia sexiesperforata (Dias et al. 2017). ...
Este libro presenta los resultados de la segunda evaluación del riesgo de extinción de invertebrados marinos en Colombia, un esfuerzo coordinado por INVEMAR y MINAMBIENTE, que involucró a 53 investigadores nacionales y contó con la asesoría del personal de la UICN.
... No existen estudios de la especie en Colombia; sin embargo, un estudio sobre distribución y abundancia de caracoles en general en La Guajira reportó densidades de 0,8 ± 4,4 ind/ha, en un área comprendida entre las poblaciones de Riohacha y Camarones (Nieto-Bernal et al. 2013). El valor es bajo comparado con las densidades reportadas en áreas de pastos marinos sin presión de pesca en diferentes localidades (hasta 15,8 ind/ha), pero similar a los valores reportados en sitios donde se extrae la especie (Tewfik y Scheuer 2013). ...
... Se ha sugerido que los bancos de macroalgas serían un sustrato importante para el desove de la especie (Dias y Mota 2015). Son depredadores carnívoros oportunistas que se alimentan exclusivamente de equinoideos, utilizando las especies presa más abundantes (Tewfik y Scheuer 2013). Algunas presas frecuentes del casco real son Diadema antillarum, Echinometra lucunter, Lytechinus variegatus, y Tripneustes ventricosus, y en ocasiones los dólares de mar Mellita quinquiesperforata y Leodia sexiesperforata (Dias et al. 2017). ...
Anteriormente aceptada con el nombre Farfantepenaeus notialis, pero a partir del trabajo de Ma et al. (2011) quedó clara la monofilia del género Penaeus sensu lato, que incluye los géneros Penaeus, Fenneropenaeus, Litopenaeus y Farfantepenaeus.
... holes on Agassizia tests are interpreted as the result of predation by cassid gastropods. The attribution is supported by the general shape and size of the bore holes and the well-documented gastropod-echinoid interactions as found in living populations of both regular and irregular echinoids, including spatangoids (e.g., Moore, 1956;Hughes andHughes, 1971, 1981;Hughes, 1986;Gerace and Lindsay, 1992;Lindsay, 1996;Tewfik and Scheuer, 2013;Grun, 2017;Tyler et al., 2018). Hughes (1986) described in detail the hunting technique used by the cassid Galeodea echinophora (Linnaeus, 1758) to prey on the infaunal spatangoid Echinocardium cordatum. ...
... Cassids feed almost exclusively on echinoids (e.g., Hughes andHughes, 1971, 1981;Tewfik, 2014;Tyler et al., 2018), opportunistically preying on the locally most abundant species (see Tewfik and Scheuer, 2013 and references therein) and exerting high predation pressures on echinoid populations (e.g., Gladfelter, 1978;Engstrom, 1982; McClintock andMarion, 1993;Lindsay, 1996;Tyler et al., 2018). ...
Predation is of great importance in understanding the diversification of spatangoid echinoids as well as their preservation in the fossil record. Herein, the spatangoid-dominated Miocene carbonate succession of Punta Foghe (Montiferru area, central-western Sardinia, Italy) is studied with the aim of reconstructing paleoenvironmental conditions and investigating abiotic and biotic factors, including predation, that influence the paleoecology and preservation potential of spatangoid echinoids.
The echinoid fauna is dominated by the spatangoid Agassizia and, to a lesser extent, the clypeasteroid Clypeaster . The fauna also includes both regular (undetermined diadematoids and camarodonts) and irregular ( Plagiobrissus, Echinocyamus , and Koehleraster ) forms. Echinoids and associated fossil content, along with taphonomic and sedimentological signatures, indicate an inner sublittoral environment with moderate energy conditions affected by high-energy events. Agassizia remains, which consist mainly of complete and well-preserved tests, commonly bear subcircular drill holes that are interpreted as the result of cassid gastropod predation and investigated with respect to size selectivity and stereotypy of attack sites. Potential biases related to drilling predation and biostratinomy on the preservation potential of spatangoid tests are discussed.
Agassizia lacks any morphological adaptation to minimize high predation risk, including defensive spines and the ability to burrow deeply into the sediment. An antipredator behavior possibly relied on a gregarious life-history strategy, reducing the frequency of attacks on specific individuals by cassid predators.
... When evaluating the abundance of mollusc species, we detected a dominance of carnivore gastropods (53% of the species), hosting 34 species belonging to 25 genera. Some examples of carnivore species are included in families like Cassidae which feed on echinoids (Tewfik, 2013), Conidae that feed mainly on polychaete worms (Jiménez-Tenorio et al. 2019) and Muricidae with Naticidae that drill to feed on mollusc shells (Sawyer & Zuschin, 2011). Also, we observed a striking presence of bivalve suspension feeders, for example Megacardita sp., which require relatively high hydrodynamics. ...
... Circular to sub-circular borings (Oichnus-like holes) could potentially be the result of either predation or postmortem bioerosion. Similar boreholes are described on the clypeasteroids Mellita, Leodia, and Clypeaster (Moore 1956;Lindsay 1996;Tewfik and Scheuer 2013;Tewfik 2014) and the much smaller Echinocyamus and Fibularia (Nebelsick and Kowalewski 1999;Ceranka and Złotnik 2003;Grun et al. 2014Grun et al. , 2017. These have been interpreted as the result of the lethal predation of cassid gastropods, which prey upon echinoids by drilling into the test and leaving circular to subcircular bore holes. ...
Clypeasteroid echinoids are widespread and abundant within Miocene sedimentary sequences of the Mediterranean area within both siliciclastic and carbonate deposits. Herein, three clypeasteroid-dominated echinoid assemblages from the mixed siliciclastic-carbonate succession of the Mores Formation (lower Miocene) cropping out within the Porto Torres Basin (northern Sardinia) are described. These assemblages were compared to previously described clypeasteroid-bearing deposits from the Miocene of northern Sardinia with the purpose of investigating their palaeoecology and taphonomy along a shelf gradient. These goals are accomplished by various methods including (i) logging sedimentary facies, (ii) analysing the functional morphology of sea urchin skeletons, (iii) comparing the relative abundance of taxa and taphonomic features, and (iv) studying associated fauna, flora, and trace fossils. The clypeasteroid-bearing deposits differ greatly with respect to echinoid diversity, accompanying fauna and flora, sedimentological signatures, and taphonomic features. They also show variations in depositional environments and the mechanism of formation of the deposits. Three different shelf settings are distinguished: littoral, inner sublittoral, and outer sublittoral environments. Furthermore, an ecomorphological gradient along the shelf is recognized with respect to echinoid taxa and their morphologies. This gradient ranges from shallow water to a moderately deep shelf and is interpreted with respect to both abiotic and biotic factors as well as the taphonomy of the echinoid tests.
... The king helmet Cassis tuberosa (Linnaeus 1758) ( Figure 1) is a large marine gastropod mollusk belonging to the family Cassidae and is distributed from North Carolina to Brazil (Rios 2009), including the Gulf of Mexico, Caribbean and Cape Verde Islands, Western Africa (Tewfik and Scheuer 2013). In Brazil, it is found from Pará to Espírito Santo states (Rios 2009). ...
... Currently, the few studies that mention the abundance of this species have revealed a low number of individuals. In the Turks and Caicos Islands, the density of Cassis tuberosa associated with dense seagrass beds (Thalassia testudinum) ranged from 2.6 to 15.8 individuals/ha (Tewfik andScheuer 2013; Tewfik 2015), while in La Guajira (Colombia), NietoBernal et al. (2013) recorded a density ranging from 0.3 to 0.8 individuals/ha. A low density of this predator was also reported by Engstrom (1982), who mentioned one individual/660 m 2 (=15 individuals/ha) in Pitahaya and one individual/14,000 m 2 (=0.7 individuals/ha) in Guayacan, both in Puerto Rico. ...
... This information is very important considering the susceptibility of prey consumed by C. tuberosa to processes such as acidification of ocean water, imbalance of macroalgal communities, which are the crucial food of sea urchins, and erosion and decharacterization of sandy beaches, which are among the essential habitats of the sand dollars. Although shell size structure data are important for interpreting the size and possibly age of individuals (Tewfik and Scheuer 2013), exact information on growth, size at first sexual maturation and essential habitat of recruits, young and adults, are nonexistent. ...
Cassis tuberosa is a key species in reefs and sandy beaches, where it plays an essential role as a predator of sea urchins and sand dollars. Due to the beauty of its shell, it is one of the most exploited species for trade as marine souvenirs throughout its distribution in the Western Atlantic. Despite its ecological importance, there is little available information about population and biological data or the impacts of its removal from its natural habitats. Considering the economic and ecological importance of this species, this study provides a short review of existing studies and highlights research and conservation needs for this highly exploited marine gastropod.
... A number of other direct and indirect interactions are not illustrated. 300 m long transects, depending on site specific conditions, and extrapolated to individuals per hectare (Tewfik et al. 2007, Tewfik and Scheuer 2013, Tewfik 2014. Coverage of macrophytes, primarily seagrass, along transects was characterized using a mean of three to five 25-x 25-cm quadrats (% cover ± 5%). ...
... Coverage of macrophytes, primarily seagrass, along transects was characterized using a mean of three to five 25-x 25-cm quadrats (% cover ± 5%). All sites were assessed as medium (30 -70% cover) or dense (> 70%) seagrass (Mumby and Harborne 1999, Tewfik and Scheuer 2013, Tewfik 2014) and will not be discussed further. All megainvertebrates were measured (150 or 300 mm Vernier calipers +/-1 mm) along the longest body axis, shell length (SL, tip of the spire to siphonal canal) for all gastropods. ...
... All megainvertebrates were measured (150 or 300 mm Vernier calipers +/-1 mm) along the longest body axis, shell length (SL, tip of the spire to siphonal canal) for all gastropods. Two sites (Fresh Creek Cays, Andros, Bahamas; East Bay, South Caicos, Turks & Caicos Is.) had additional data collected haphazardly by snorkeling in order to encounter the greatest number of predatory gastropods for the purposes of tagging and identification of active predation events (Tewfik and Scheuer 2013). Observations included prey species under attack as well as presence of broken, crushed or empty predatory gastropod shells and identification of potential predators of predatory gastropods (e.g. ...
A number of large, predatory gastropods including Chanks (Turbinellidae), Helmets (Cassidae), and Tritons (Ranellidae) are targeted by fishers supplying the trade in collectible shells, components of decorative souvenirs, and a source of food in some areas. However, the over-harvesting of these predators is considered a contributing factor in population increases of their prey resulting in the alteration of shallow-water ecosystem dynamics and loss in biodiversity. Similar cascading effects have been documented in a number of other marine systems in which over-harvesting of predators (e.g. fish, lobsters, sea otters) have resulted in the release of prey and fundamental shifts in benthic communities. Given our limited understanding of predatory gastropods this overview intends to: (1) highlight the importance of predatory gastropods within complex Caribbean seascapes; (2) demonstrate how assessments of gastropod predators may be integrated into existing benthic resource surveys: and (3) provide new information on the ecology and status of several species of predatory gastropods (Cassis flammea, Cassis tuberosa, C. madagascariensis, Charonia variegata, Turbinella angulata) inhabiting seagrass habitats in The Bahamas, Belize and the Turks and Caicos Islands.
Examining activity patterns is essential in understanding gastropod feeding and movement ecology. However, the diel activity patterns of large-bodied gastropods, such as Cassis cornuta, remain poorly studied. Here, we conducted outdoor hatchery-based experiments to examine the diel activity patterns of C. cornuta adults and juveniles under natural sunlight and photoperiod. Activities of C. cornuta, such as crawling, hunting, feeding, burrowing and resting on the substratum, were examined every hour for 3 days. Although most individuals were inactive for a greater part of the observation period, active behaviours were recorded for some individuals during both daytime and nighttime, suggesting that C. cornuta is cathemeral, as supported by a nonsignificant result from a Rayleigh's test of uniformity. A higher proportion of adult and juvenile C. cornuta were inactive, either burrowed or resting on the substratum, during the 24-h period. Peak activity time for juveniles started at 20:00, with up to 50% of individuals active, while peak activity time for adults started at 21:00, with up to 20% of active individuals. Adults spent more time resting aboveground, whereas juveniles spent more time burrowed under the sand when not feeding. Juveniles hunted more frequently and spent more time feeding compared to adults. Additionally, juveniles crawled faster and were more successful in capturing sea urchins than adults. The information on variability in the diel activity patterns and movement rates between adult and juvenile C. cornuta would allow further demographic studies, and provide insights into possible conservation strategies for this species.
The inhabitants of small offshore islands are highly dependent on the health and availability of their resources. However, pieces of information about the commonly gleaned species in some remote areas are sparsely documented. In this study, we inventoried the species composition of the widely gleaned macro-benthic invertebrates such as gastropods, bivalves, and sea cucumbers in Cawili Island, a small inhabited island in the middle of the Sulu Sea in Palawan, Philippines. The samples obtained from fishers and snorkeling activities in shallow areas revealed a total of 85 species belonging to 27 families. Most of these were gastropods, composed of 68 species under 20 families. The list includes nine protected species (four gastropods, two bivalves, and three sea cucumbers). Gastropods and bivalves were mostly used for food and display in the house of the fishermen (souvenir), while the sea cucumbers were exclusively harvested for trade. Sustainable fishery activities are needed in this small offshore island where people heavily rely on their marine resources.
