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Sea urchins (echinoids) were integrated into many aspects of prehistoric Oceanic society as they provided food, raw material for abrading tools and rare ornaments, and were used as offerings on shrines (ko‘a) in the Hawaiian Islands. We privilege seven habitation and shrine assemblages (mostly dating to late prehistory; i.e., post AD 1500s) situated along a ∼12-km length of the rocky windward coast of Moloka‘i, Hawaiian Islands, where some of the densest concentrations of urchins have been recorded from Oceania. We examined >185,000 urchin fragments weighing nearly 11.7 kg which, we believe, is the largest analyzed sample to date. Focusing primarily on the helmet urchin (Colobocentrotus atratus), found throughout the Indo-Pacific, we used a protocol for accurately calculating the minimum numbers of individuals using unique test (endoskeleton) plates and internal mouthparts, demonstrated the dietary importance of urchins for marine subsistence, constructed an allometric formula for calculating individual urchin size, and discussed the relevance of urchins for monitoring long-term human impacts to this important coastal resource. While the study sites contained overwhelmingly limpets (Cellana spp.), urchins supplied >80% fat and nearly 40% protein of some of the invertebrate assemblages. It was documented that slightly larger urchins were placed as offerings on a shrine in contrast to smaller individuals associated with habitation structures.

Pantai Gunung Kidul memiliki beberapa biota laut salah satunya bulu babi (Echinodermata). Penelitian ini bertujuan mengidentifikasi jenis bulu babi di kawasan perairan pantai Gunung Kidul, Yogyakarta. Penelitian bulu babi di kawasan perairan pantai Gunung Kidul dilakukan pada bulan April sampai dengan Mei 2018 di 3 (tiga) lokasi yaitu Pantai Drini, Pantai Ngrenehan, dan Pantai Widodaren. Pengambilan data dilakukan dengan menggunakan metode transek kuadrat ukuran 1m x 1m. Dari hasil penelitian diperoleh 7 (tujuh) jenis bulu babi yang tergolong dalam 4 (empat) famili dan 3 (tiga) ordo. Jumlah jenis bulu babi yang paling banyak ditemukan di Pantai Widodaren, dengan total 6 (enam) jenis, yaitu Echinometra sp., Echinometra mathaei, Heterocentrotus sp., Tripneustes ventricosus, Colobocentrotus atratus dan Arbacia lixula. Sedangkan di Pantai Drini dan Ngrenehan ditemukan masing-masing 4 (empat) jenis yaitu Echinometra sp. Echinometra mathaei, Heterocentrotus sp.,dan Stomopneustes variolaris.

Thermal limits of marine ectotherms are influenced by the dynamics of oxygen supply and demand; all else being equal, as temperature increases, metabolic demand eventually outpaces an organism's capacity for oxygen uptake and delivery. We tested the combined effects of oxygen and temperature on an intertidal wave-zone obligate sea urchin , Colobocentrotus atratus, to examine whether oxygen limitation during submersion may limit the lower vertical distribution of this species. We measured survival and attachment strength under both ambient (21%) and enriched (35%) O2 conditions and at a range of temperatures between 25 and 37 °C. Oxygen enrichment increased survival at warmer temperatures, demonstrating oxygen limitation during submergence at high temperatures. Attachment strength declined with increasing temperature, but, unlike survivorship, was not affected by O 2 enrichment. Our data suggest that the lower limit on vertical distributions of C. atratus are set in part by abiotic stresses experienced under immersion, and that hypoxic stress will increase with warming sea temperatures. Thus, warmer oceans may reduce the amount of viable habitat for C. atratus, and other intertidal marine taxa that are specialized for aerial gas exchange, due to increasing abiotic stress at the bottom of their vertical distribution.

* Colobocentrotus (Podophora) atratus (Linnaeus, 1758) Fig. 46 A–B. Colobocentrotus auratus: A. Agassiz, 1872: 102, 424. Pl. XXXVI, Figs 6–7. Pl. XXXVIII, Figs 11–12; Samyn, 2003: 204, Fig. 3 D. Podophora atrata: H.L. Clark, 1925a; 145; H.L. Clark, 1912: 376. Colobocentrotus (Podophora) atratus: Mortensen, 1943: 434 –439. Pl. L, Figs 1–2. Pl. LlI, Figs 1–2. Pl. LXV, Fig. 7; Filander & Griffiths, 2014: 52 –53. Pl. I, Fig. A. Podophora atratus: Schultz, 2010: 232, Figs 441–443. Material examined. Photographic image uploaded on VM EchinoMaps. Identification. Test solid, transversely elongated. Spines eccentric, closely packed, flat, forming tessellate arrangement ending in a fringe; purple coloration. Global maximum size. Maximum test diameter 65 mm. Global distribution. East coast region of South Africa (Filander & Griffths 2014); East Africa to Malayan Archipelago, as far as Hawaii; restricted to littoral zones (Schultz 2010). Remarks. The test morphology is strongly adapted for attachment to strongly wave-exposed rocks, thus minimizing possibility of being washed away by wave action. Reported to feed on encrusting organisms., Published as part of Filander, Zoleka & Griffiths, Charles, 2017, Illustrated guide to the echinoid (Echinodermata: Echinoidea) fauna of South Africa, pp. 1-72 in Zootaxa 4296 (1) on page 43, DOI: 10.11646/zootaxa.4296.1.1, http://zenodo.org/record/843325, {"references":["Linnaeus, C. (1758) Systema Naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Editio decima, reformata. Laurentius Salvius, Holmiae, 824 pp.","Agassiz, A. (1872) Revision of the Echini. Memoirs of the Museum of Comparative Zoology at Harvard College, 3, 1 - 378.","Clark, H. L. (1925 a) A Catalogue of the Recent Sea-urchins (Echinoidea) in the Collection of the British Museum (Natural History). Trustees of the British Museum, London, 250 pp.","Clark, H. L. (1912) Hawaiian and other Pacific Echini. The Pedinidae, Phymosomatidae, Stomopneustidae, and Echinometridae.","Mortensen, T. (1943 a). A Monograph of the Echinoidea. III. 2. Camarodonta. I. Orthopsidae, Glyphocyphidae, Temnopleuridae and Toxopneustidae. C. A. Reitzel, Copenhagen, 553 pp.","Filander, Z. & Griffiths, C. L. (2014) Additions to and revision of the South African echinoid fauna (Echinodermata: Echinoidea). African Natural History, 10, 47 - 56.","Schultz, H. (2010) Sea-Urchins, a Guide to Worldwide Shallow Water Species. 3 rd Edition. Scientific Publication, Hemdingen, 484 pp."]}

The peculiar limpet-like morphology of the genus Colobocentrotus is unique among the regular echinoids. This shape has been interpreted as an adaptation to life in areas of extreme wave exposure. In this study the attachment strength of C. atratus is compared with that of three sympatric species, Echinometra mathaei, Heterocentrotus trigonarius and Stomopneustes variolaris, which have more typical echinoid morphology and live in different microhabitats. For each species, the adhesion of individual sea urchins was measured as well as the tenacity of single tube foot and the mechanical properties of the tube foot stems. Colobocentrotus always presented the highest measured values, although not always significantly different from those of the other species. Of the mechanical properties of the stem measured, the stem extensibility was the only property that was significantly different among species. In general the stems of all the species studied became more extensible and more difficult to break with increasing strain rate, providing an adaptative advantage to the sea urchin when subjected to rapid loads such as waves. In terms of single tube foot tenacity, C. atratus tube feet attached with a tenacity (0.54 MPa) two times higher than the one of E. mathaei, H. trigonarius and S. variolaris (0.21-0.25 MPa). Individual sea urchins of the four species, however, attached with a similar strength (0.2-0.26 MPa). The calculation of safety factors showed that it is the very high number of adoral tube feet of C. atratus and not the overall shape of the animal that allows this species to withstand very high water velocities. However, C. atratus streamlined morphology may be a functional adaptation to reduce the impact of other hydrodynamic forces (such as wave impingement forces) or to cope with other selective environmental stresses (such as dessication), and thus to inhabit extremely exposed areas of the intertidal.

Twenty-six, polymorphic microsatellite loci were developed for the tropical sea urchin Colobocentrotus atratus. Microsatellite enriched genomic libraries were constructed and subsequently sequenced using Roche 454 technology. The 26 loci were characterized in 21 individuals from Pulau Asu, Nias, Indonesia. Observed levels of heterozygosity ranged from 0.52 to 1.00 with a mean of 11.9 alleles per locus. No pairs of loci showed evidence of significant linkage disequilibrium and 3 loci significantly deviated from Hardy–Weinberg expectations.

Echinoderms are important constituents of marine ecosystems, where they may influence the recruitment success of benthic flora and fauna, and are important consumers of detritus and plant materials. There are currently no described viruses of echinoderms. We used a viral metagenomic approach to examine viral consortia within three urchins –Colobocentrotus atratus,Tripneustes gratillaandEchinometra mathaei– which are common constituents of reef communities in the Hawaiian archipelago. Metagenomic libraries revealed the presence of bacteriophages and densoviruses (familyParvoviridae) in tissues of all three urchins. Densoviruses are known typically to infect terrestrial and aquatic arthropods. Urchin-associated densoviruses were detected by quantitative PCR in all tissues tested, and were also detected in filtered suspended matter (>0.2 µm) from plankton and in sediments at several locations near to where the urchins were collected for metagenomic analysis. To the best of our knowledge, this is the first report of echinoderm-associated viruses, which extends the known host range of parvoviruses.

Physical properties (density in kg m-3, viscosity, sinking rates and dispersion rate) of the gametes and associated spawned materials were measured for three species of sea urchin, Tripneustes gratilla, Echinometra mathaei and Colobocentrotus atratus, from habitats that differ in wave exposure. The gametes of all three species are negatively buoyant, highly viscous and exhibit shear-thinning (a decrease in viscosity with increasing shear rate). Female gametes are more viscous than male gametes, and the viscosity of female gametes differs among the three species. The viscosity of female gametes is highest for C. atratus, the species from habitats most exposed to wave action. Within the species T. gratilla, viscosity of female gametes is higher in habitats exposed to wave action than in more protected habitats. Evidence reported in this paper suggests that the shear-thinning of gametes may provide a performance advantage for these sea urchins. High viscosity of gametes at low shear rates may decrease gamete dispersal upon release and, under certain flow conditions, allow gametes to form strings and clumps on the surface of the urchin. Depending upon the morphology of the surface, these clumps or strings may be retained and fertilization may occur within these clumps or strings. Conversely, low viscosity of gametes at high shear rates decreases the power required to extrude gametes through the gonoduct during spawning.

The performance requirements of ciliary band feeding explain the convoluted forms of many marine in- vertebrate larvae. Convolutions increase surface area and therefore feeding rates per unit body volume. We review recent advances in morphology, neural development, and behavior at settlement of the echinoid Lytechinus pictus and provide new ultrastructural and expression data on larvae of its congener, L. variegatus. Larvae of the echinometrid Colobocentrotus atratus contain neurons identified by their expression of nitric oxide synthase (NOS), indicating that this character is not unique to Lytechinus. We hypothesize that in some echinoids the convoluted shape of the post-oral vibratile lobe (POVL) covaries with the distribution of identified sensory neurons to enable olfaction during settle- ment. An analysis of variation in structural elaboration of the post-oral transverse ciliary band (PTB) within Echinoida and in feeding larvae of other echinoderm classes indicates that only echinoids, but not all echinoids, possess this novel character; larvae that do are distributed heterogeneously within the class. In recognition of this specialized function for the POVL and surrounding ectoderm, and because it is lobate and grows toward the mouth, we propose naming this structure the adoral lobe.

Two species of sea urchins (Colobocentrotus atratus and Echinometra mathaei) commonly co-occur on wave-swept intertidal shores in the Indo West Pacific. E. mathaei is a typical spiny urchin and is confined to cavities in the rock. In contrast, C. atratus has an unusual morphology, in which the spines are much reduced, and is found on substrata fully exposed to wave-induced velocities and accelerations. Previous researchers have suggested that spine reduction may therefore be a morphological adaptation to hydrodynamic forces. However, measurement of the drag, lift and accelerational forces on sea urchins show that the adaptive significance of spine reduction is less straightforward than it initially appears. The reduction in drag in C. atratus as compared with that in E. mathaei is to a large extent offset by an increase in lift. Instead, the ‘streamlined’ morphology of C. atratus seems best adapted to provide a reduction in the force imposed by water acceleration, thereby making it feasible for C. atratus to venture safely into the tumultuous flows of the surf zone.

The relationships among egg size, larval growth and form, and the functional consequences of larval form, (e.g. the changing relationship between ciliated band length and metabolic activity) were compared among four co-occurring echinoids, Strongylocentrotus droebachiensis (O. F. Muller), S. franciscanus (A. Agassiz), S. purpuratus (Stimpson), and Dendraster excentricus (Eschscholtz). Development time from fertilization to the formation of the echinus rudiment, just prior to metamorphic competence, was inversely related to egg volume. Egg sizes spanned a 6-fold range in volume, corresponding to a doubling of developmental duration. Species with smaller eggs should have greater fecundity per unit reproductive effort. However, the larval stages should suffer greater planktonic predation as a result of slower development. In general, the initial differences in larval size and shape that are related to egg size do not persist throughout development. The quantitative importance of shape change in increasing the size of feeding structures relative to support structures is uniformly high (80–85% of total change is allometric) in these species. During the period of arm formation (2-armed stage to 8-armed stage), ciliated band length scaled with strong positive allometry with respect to body length. The allometric exponents ranged from 2.7 to 3.4 and were positively related to egg size. Species with larger eggs have greater inherent capability for increasing the size of feeding structures relative to support structures during growth. Likewise, the sealing of feeding capability with respect to metabolic activity was positively related to egg size, with the allometric exponents ranging from 0.8 to 1.5. An important consequence of increased egg size is the increased ability to seale feeding structures positively with respect to the geometric and energetic size of the larva.

Egg protein content, and presumably total organic content (parental investment), was linearly related to egg volume among seven species of echinoids with planktotrophic larval development: Strongylocentrotus droebachiensis (O.F. Muller), S.purpuratus (Stimpson), S.franciscanus (A. Agassiz), Dendraster excentricus (Eschscholtz), Heterocentrotus mammillatus (Klein), Colobocentrotus atratus (Linnaeus), and Tripneustes gratilla (Linnaeus). Initial larval size and feeding capability, at the 2-armed and 4-armed pluteus stages, were positively correlated with egg size. The complexity of larval shape, as ciliated band length or total arm length relative to body length, was independent of egg size. Initial feeding efficiency, defined as the ratio of feeding capability to larval respiratory electron transport system (ETS) activity, was inversely related to egg size. This was the result of a strong dependence of metabolism on body size. Important differences in the egg size and larval form relationships were observed among the different echinoid families and between geographic regions. It is predicted that species with larger eggs and larger initial larvae will either remain larger at each stage of development or develop to a given stage faster than species with small eggs. These relationships between egg size and larval form may constrain selection for certain reproductive or larval traits such as egg size, fecundity, larval form, development rate, total development period, and size at metamorphosis, thereby limiting the evolutionary flexibility of reproductive pattern.

Spermatozoa from the sea urchin, Colobocentrotus atratus, were partially demembranated by extraction with solutions containing Triton X-100 at a concentration which was insufficient to solubilize the membranes completely. The resulting suspension was a mixture containing some spermatozoa in which a proximal, medial, or distal portion of the flagellum was membrane-covered, while the remaining portion was naked axoneme. In reactivating solutions containing 12 µM ATP, only the naked portions of the flagellum became motile. In reactivating solutions containing 0.8 mM ADP, the membrane-covered regions became motile and beat at 6-10 beats/s, while the naked regions remained immobile, or beat very slowly at about 0.3 beat/s. Activation of membrane-covered regions in ADP solutions probably results from the membrane restricting the diffusion of ATP which is formed from ADP by the axonemal adenylate kinase. The results indicate that any region of the flagellum has the capacity for autonomous beating, and that special properties of the basal end of the flagellum are not required for bend initiation. However, the beating of different regions of the flagellum is not completely independent, for in a fair number of spermatozoa the beating of the distal, membrane-covered region in 0.8 mM ADP was intermittent, and was turned on and off in phase with the much slower bending cycle in the proximal region of naked axoneme.

Treatment of the eggs of the sea urchin with a 1 M solution of glycerol at fertilization allows the recovery from this solution of the protein released from the cortical granules, including that which would normally give rise to the hyaline layer. The calcium-gelable protein previously extracted from whole eggs and from isolated cortical material was found to be present in the glycerol solution, confirming its localization in the cortical granules and its role in the hyaline layer. Quantitative measurements on the eggs of two Hawaiian species, Colobocentrotus atratus and Pseudoboletia indiana, which have the widest variation in the gel protein content, demonstrated that a proportionate amount of this material was released at fertilization in these species, which correlates with the thickness of the hyaline layer in the two cases. In addition, the calcium-insoluble fraction of Sakai can be extracted from these eggs after removal of the hyaline protein by glycerol, showing that this is a different material. A simple method for the separation of the hyaline protein from the calcium-insoluble fraction in solution is provided.

The histochemical method for the detection of alkaline phosphatase according to the schedule of Danielli was applied to whole eggs and embryos and to histological sections of different developmental stages of Tripneustes gratilla and Colobocentrotus atratus. Sections of oocytes showed little or no alkaline phosphatase activity except in the nucleolus. The rest of the nucleoplasm and the whole cytoplasm could not be distinguished from the control. In mature ova of T. gratilla the nucleus showed higher enzyme activity than the cytoplasm. In pigmented eggs of C. atratus this method could not show the enzyme activity in the ovum and cleavage stages in total mount preparations. In both species tissue distribution of alkaline phosphatase occurs with the beginning of gastrulation. In gastrula the archenteron and primary mesenchyme cells had higher activity than the other tissues. In later stages, from gastrula to pluteus, the wall of the gut consistently showed higher activity than other tissues. The primary mesenchyme cells and their descendant skeletogenic cells of the endoskeleton showed the next concentration of this enzyme. The hydroenterocoels, which began as evaginations from the dorsal wall of the gut and had this enzyme, were devoid of activity after separation from the gut. The ectodermal cells of the anterior border of the pluteus also had enzyme activity, although it was lower in concentration than the gut and the skeletogenic mesenchyme cells. Mature eggs, gastrulae and plutei of the Hawaiian sea urchin Tripneustes gratilla were studied biochemically for changes in alkaline phosphatase activity during development. The increase in precipitation produced by the Gomori-Takamatsu technique at the different stages studied parallels the increase in inorganic phosphorus released from the substrate by incubation of similar stage of material in direct biochemical analysis. In the mature ova of this species the Qp value of alkaline phosphatase activity was about half as much as that of the gastrulae and the plutei were about six times as active enzymatically as the unfertilized eggs and about three times as active as the gastrulae.