Figure 1 - uploaded by John S. Ryland
Content may be subject to copyright.
The types of nematocyst found in zoanthids. (A, A¢) Atrich, Palythoa caesia. (B, B¢) Small holotrich (holotrich II), Palythoa tuberculosa. (C, C¢) Small holotrich, Parazoanthus axinellae. (D, D¢) Large holotrich (holotrich I), Palythoa caesia. (E, E¢) Large basitrich, Palythoa tuberculosa. (F, F 0 ) Medium basitrich, Palythoa tuberculosa (a form with a short shaft occurs in Parazoanthus axinellae). (G, G¢) Microbasic p-mastigophore, Palythoa tuberculosa. (H, H¢) Microbasic b-mastigophores, Parazoanthus axinellae (H), Zoanthus coppingeri ¼ pacificus (H¢). Except A¢ and D, from Schmidt (1974).

The types of nematocyst found in zoanthids. (A, A¢) Atrich, Palythoa caesia. (B, B¢) Small holotrich (holotrich II), Palythoa tuberculosa. (C, C¢) Small holotrich, Parazoanthus axinellae. (D, D¢) Large holotrich (holotrich I), Palythoa caesia. (E, E¢) Large basitrich, Palythoa tuberculosa. (F, F 0 ) Medium basitrich, Palythoa tuberculosa (a form with a short shaft occurs in Parazoanthus axinellae). (G, G¢) Microbasic p-mastigophore, Palythoa tuberculosa. (H, H¢) Microbasic b-mastigophores, Parazoanthus axinellae (H), Zoanthus coppingeri ¼ pacificus (H¢). Except A¢ and D, from Schmidt (1974).

Source publication
Chapter
Full-text available
Seven different types of nematocyst are detailed and illustrated from the Zoanthidea. We studied the size population structure of nematocyst capsules: how they are affected by preservation, and how and what should be measured. Populations of two types, large holotrichs and p-mastigophores, from the mesenterial filaments of Protopalythoa heliodiscus...

Contexts in source publication

Context 1
... to debate. In this paper we first re- view the types of nematocyst recorded in Zoan- thidea, updating the surveys of Schmidt (1972Schmidt ( , 1974, and then explore the use of quantitative data, following the procedural recommendations recently formulated ( . For recognition of nematocyst types, of which at least seven are known for Zoanthidea ( Fig. 1), we fol- low Schmidt (1972,1974), because of his clear diagrams ( Fig. 1), but prefer a terminology based on that of Weill (1934). The first group of types comprises: large holotrichs (holotrichs I of Schmidt) or holotrichous isorhizas (i.e. with par- allel sided tubule; Fig. 1D); small holotrichs (holotrichs II) which, from Schmidt's ...
Context 2
... in Zoan- thidea, updating the surveys of Schmidt (1972Schmidt ( , 1974, and then explore the use of quantitative data, following the procedural recommendations recently formulated ( . For recognition of nematocyst types, of which at least seven are known for Zoanthidea ( Fig. 1), we fol- low Schmidt (1972,1974), because of his clear diagrams ( Fig. 1), but prefer a terminology based on that of Weill (1934). The first group of types comprises: large holotrichs (holotrichs I of Schmidt) or holotrichous isorhizas (i.e. with par- allel sided tubule; Fig. 1D); small holotrichs (holotrichs II) which, from Schmidt's depiction of a tapering tubule, appear to be holotrichous an- isorhizas ...
Context 3
... nematocyst types, of which at least seven are known for Zoanthidea ( Fig. 1), we fol- low Schmidt (1972,1974), because of his clear diagrams ( Fig. 1), but prefer a terminology based on that of Weill (1934). The first group of types comprises: large holotrichs (holotrichs I of Schmidt) or holotrichous isorhizas (i.e. with par- allel sided tubule; Fig. 1D); small holotrichs (holotrichs II) which, from Schmidt's depiction of a tapering tubule, appear to be holotrichous an- isorhizas (Fig. 1B and C); and large atrichs -not included by Schmidt in the zoanthid assemblage although they had been recorded from the order by Cutress (1955) (Fig. 1A) and are present in the Actiniaria, from one ...
Context 4
... holotrichous isorhizas (i.e. with par- allel sided tubule; Fig. 1D); small holotrichs (holotrichs II) which, from Schmidt's depiction of a tapering tubule, appear to be holotrichous an- isorhizas (Fig. 1B and C); and large atrichs -not included by Schmidt in the zoanthid assemblage although they had been recorded from the order by Cutress (1955) (Fig. 1A) and are present in the Actiniaria, from one division of which (End- omyaria) Schmidt (1974) derived the Zoanthidea. The second group comprises the various mastigo- phores: nematocysts with slender elongate capsules which, following England (1991) -who broadened Weill's (1934) original description to include mastigophores in which the ...
Context 5
... (1974) derived the Zoanthidea. The second group comprises the various mastigo- phores: nematocysts with slender elongate capsules which, following England (1991) -who broadened Weill's (1934) original description to include mastigophores in which the shaft is wider, but only slightly wider, than the rest of the tubule -we identify as basitrichs ( Fig. 1E and F; microbasic b-rhabdoids of Schmidt); p-mastigophores ( p-rhabdoids of Schmidt), with a wide, sharply defined shaft (Fig. 1G); and microbasic b-mastig- ophores sensu stricto (special b-rhabdoids of Schmidt; Fig. 1H) which, in zoanthids, are more ovoid and less fusiform than basitrichs, and which -according to Schmidt (1974) -are ...
Context 6
... which, following England (1991) -who broadened Weill's (1934) original description to include mastigophores in which the shaft is wider, but only slightly wider, than the rest of the tubule -we identify as basitrichs ( Fig. 1E and F; microbasic b-rhabdoids of Schmidt); p-mastigophores ( p-rhabdoids of Schmidt), with a wide, sharply defined shaft (Fig. 1G); and microbasic b-mastig- ophores sensu stricto (special b-rhabdoids of Schmidt; Fig. 1H) which, in zoanthids, are more ovoid and less fusiform than basitrichs, and which -according to Schmidt (1974) -are restricted to the 'higher' Zoanthidea (a term of his own which we equate with all the Macrocnemina plus part (family Zoanthidae ...
Context 7
... mastigophores in which the shaft is wider, but only slightly wider, than the rest of the tubule -we identify as basitrichs ( Fig. 1E and F; microbasic b-rhabdoids of Schmidt); p-mastigophores ( p-rhabdoids of Schmidt), with a wide, sharply defined shaft (Fig. 1G); and microbasic b-mastig- ophores sensu stricto (special b-rhabdoids of Schmidt; Fig. 1H) which, in zoanthids, are more ovoid and less fusiform than basitrichs, and which -according to Schmidt (1974) -are restricted to the 'higher' Zoanthidea (a term of his own which we equate with all the Macrocnemina plus part (family Zoanthidae sensu stricto) of the Brach- ycnemina (see , for discussion). Schmidt evidently perceived ...
Context 8
... had discharged two different types of tubule. In one, the tubule was wide, 4.5 lm, with large spines arranged in a triple helix. Undischarged, the tubule was loosely and ob- liquely coiled, in the manner of a vertical coil of rope that has been pulled sideways from the top, with the spines producing a banded appearance under Nomarski illumination (Fig. 1D). This type corresponded to Schmidt's (1974) holotrich I, de- scribed from Pa. tuberculosa, although he illus- trates the spines in a single helix (Fig. 1D¢). In the second type (despite the larger capsule, see below) the tubule was thinner, 3.7 lm, and appeared totally devoid of spines, even when using a ·100 oil immersion objective; ...
Context 9
... loosely and ob- liquely coiled, in the manner of a vertical coil of rope that has been pulled sideways from the top, with the spines producing a banded appearance under Nomarski illumination (Fig. 1D). This type corresponded to Schmidt's (1974) holotrich I, de- scribed from Pa. tuberculosa, although he illus- trates the spines in a single helix (Fig. 1D¢). In the second type (despite the larger capsule, see below) the tubule was thinner, 3.7 lm, and appeared totally devoid of spines, even when using a ·100 oil immersion objective; prior to discharge the tubule was coiled in the capsule like a spring ( Fig. 1A and A¢) -very different from the holotrichs. It corre- sponded with the ...
Context 10
... scribed from Pa. tuberculosa, although he illus- trates the spines in a single helix (Fig. 1D¢). In the second type (despite the larger capsule, see below) the tubule was thinner, 3.7 lm, and appeared totally devoid of spines, even when using a ·100 oil immersion objective; prior to discharge the tubule was coiled in the capsule like a spring ( Fig. 1A and A¢) -very different from the holotrichs. It corre- sponded with the atrich described by Schmidt (1974) in actinians but not recorded by him in Pa. tuberculosa or any other zoanthid, although he had evidently overlooked that Cutress (1955) had mentioned them from unspecified zoanthids as well as actinians. Our specimens matched ...
Context 11
... compared: sea water Bouin's fluid for 48 h or more followed by washing and storage in 70% ethanol, direct immersion in 70% ethanol, and 4% formaldehyde in sea water (though later samples were washed and transferred to 70% ethanol). The dimensions for basitrichs, holotrichs, and p-mastigophores are in Table 1. While the long, slender basitrichs ( Fig. 1E and F) may perhaps be adequately characterized by length, p-mastigophores are quite oval in plan view and holotrichs are oblong-oval ( Fig. 1G and D respectively). We have, therefore, measured both length and width. ANOVA of preserved basitrich lengths showed significant differences ( p ¼ 2.67 · 10 )9 ), with a similar (though less ...
Context 12
... in sea water (though later samples were washed and transferred to 70% ethanol). The dimensions for basitrichs, holotrichs, and p-mastigophores are in Table 1. While the long, slender basitrichs ( Fig. 1E and F) may perhaps be adequately characterized by length, p-mastigophores are quite oval in plan view and holotrichs are oblong-oval ( Fig. 1G and D respectively). We have, therefore, measured both length and width. ANOVA of preserved basitrich lengths showed significant differences ( p ¼ 2.67 · 10 )9 ), with a similar (though less pronounced, p ¼ 0.003-0.0001) result for length and width together using XLstat for discriminant analysis. Moreover, when measurements of fresh undischarged and ...
Context 13
... samples of Pr. mutuki came from 12 polyps from five sites and of Pr. heliodiscus from 11 polyps from seven sites; p- mastigophores of Pr. mutuki came from seven polyps from five sites and of Pr. heliodiscus from 11 polyps from seven sites (Table 1). Additionally, the clearly visible, sharply demarcated shaft in the capsule of p-mastigophores (Fig. 1G) can readily be measured, providing a third variable (Table ...

Similar publications

Article
Full-text available
We describe Andvakia discipulorum Daly & Goodwill, n. sp., from an intertidal mudflat of Kāne‘ohe Bay, O‘ahu, Hawai‘i. Members of this species are inconspicuous, being small and having a column covered with sand. In comparison with other species of the genus, Andvakia discipulorum, n. sp., presents distinct arrangement of mesenteries, sizes of nema...
Article
Full-text available
Caryophylliidae Dana, 1846 and Dendrophylliidae Gray, 1847 are families of widespread hard corals (order Scleractinia) composed mainly of azooxanthellate corals. A growing body of molecular data has provided new insights on hard-coral evolution, suggesting that many of the traditionally recognized families are not monophyletic. The morphology of th...

Citations

... (e.g. Burnett et al. 1995Burnett et al. , 1997Ryland and Lancaster 2004), and our genomic results here indicate again that more work is needed. In contrast to the extensive distribution of P. caribaeorum and P. tuberculosa in the Atlantic and Pacific oceans, respectively, the putative species P. sp. 'yoron' thus far has a restricted distribution confined to the Ryukyu Archipelago of southern Japan, and is found there in sympatry with P. tuberculosa and P. mutuki (Shiroma and Reimer 2010;Mizuyama et al., 2018). ...
Article
Full-text available
Zoantharians (Cnidaria: Hexacorallia: Zoantharia) of the genus Palythoa are ubiquitous species that occupy reef habitats in every tropical ocean. Disagreements among classifications based on morphology, reproductive traits, and molecular techniques have generated taxonomic challenges within this group. Molecular studies provide limited phylogenetic resolution between species, and discordance is frequently attributed to slow mitochondrial rates and lack of resolution among molecular markers. Here we conducted the first phylogenomic survey of Palythoa, using a reduced representation genomic approach (ezRAD) to resolve relationships among eight described and four putative Palythoa species (N = 22 plus two outgroups) across the Pacific and Atlantic Oceans. We constructed nearly complete mitochondrial genomes and assembled transcriptome loci datasets by reference mapping. A de novo assembly was performed for the holobiont dataset, and we compared a range of filtering strategies from unfiltered data down to 136 unlinked high-quality biallelic SNPs shared by all samples to resolve evolutionary lineages within Palythoa. Across all these datasets, the resulting Bayesian and ML trees revealed six highly concordant and well-supported clades, however, the phylogenomic data were inconclusive in resolving species relationships within the clades. We detected putative species complexes within two well sampled Palythoa clades (clades I and II), but species delimitation results were inconsistent in whether these clades contain multiple nominal species or represent a single variable species. Polyphyly in the broadly distributed species Palythoa tuberculosa and P. mutuki highlight the need for additional study. Consistency among nuclear and mitogenomic datasets points to a lack of biological understanding of species boundaries among these zoantharians rather than limitations of the molecular markers. More complete taxonomic sampling of nominal species across the geographic ranges of distribution is necessary to resolve species boundaries and evolutionary histories among members of this genus.
... (Rasband, 2012). Cnidae classification followed England (1991) and Ryland & Lancaster (2004), except for the treatment of basitrichs and microbasic b-mastigophores, as mentioned in . Associated hexactinellid sponges were identified based on morphology (Reiswig & Wheeler, 2002a, b ...
Article
Hexactinellid sponges are important members of deep-sea benthic ecosystems because they provide available hard substrate habitats for filter-feeding invertebrates. However, symbioses between hexactinellid sponges and their symbionts are poorly known. Zoantharians associated with hexactinellid sponges have been reported widely from deep-sea marine ecosystems, either on the bodies or stalks of hexactinellid sponges. Despite these records, there has been a lack of research on their diversity and phylogenetic relationships. In this study, 20 specimens associated with amphidiscophoran and hexasterophoran sponges were collected from the waters of Australia and Japan in the Pacific, and from Curaçao in the southern Caribbean, and these were examined in addition to museum specimens. Based on molecular phylogenetic analyses and morphological observations, we formally describe two new genera and three new species of Zoantharia and report several previously described species. The results suggest at least two independent origins for the symbioses between hexactinellid sponges and zoantharians. Our results demonstrate that the diversity of hexactinellid sponge-associated zoantharians is much higher than has been previously thought. The new taxa described in this work further reconfirm that the deep-sea harbours high levels of undescribed zoantharian diversity.
... (e.g. Burnett et al. 1995Burnett et al. , 1997Ryland and Lancaster 2004), and our genomic results here indicate again that more work is needed. In contrast to the extensive distribution of P. caribaeorum and P. tuberculosa in the Atlantic and Pacific oceans, respectively, the putative species P. sp. 'yoron' thus far has a restricted distribution confined to the Ryukyu Archipelago of southern Japan, and is found there in sympatry with P. tuberculosa and P. mutuki (Shiroma and Reimer 2010;Mizuyama et al., 2018). ...
Article
Full-text available
Zoantharians (Cnidaria: Hexacorallia: Zoan-tharia) of the genus Palythoa are ubiquitous species that occupy reef habitats in every tropical ocean. Disagreements among classifications based on morphology, reproductive traits, and molecular techniques have generated taxonomic challenges within this group. Molecular studies provide limited phylogenetic resolution between species, and dis-cordance is frequently attributed to slow mitochondrial rates and lack of resolution among molecular markers. Here we conducted the first phylogenomic survey of Pa-lythoa, using a reduced representation genomic approach (ezRAD) to resolve relationships among eight described and four putative Palythoa species (N = 22 plus two out-groups) across the Pacific and Atlantic Oceans. We constructed nearly complete mitochondrial genomes and assembled transcriptome loci datasets by reference mapping. A de novo assembly was performed for the holobiont dataset, and we compared a range of filtering strategies from unfiltered data down to 136 unlinked high-quality biallelic SNPs shared by all samples to resolve evolutionary lineages within Palythoa. Across all these datasets, the resulting Bayesian and ML trees revealed six highly con-cordant and well-supported clades, however, the phyloge-nomic data were inconclusive in resolving species relationships within the clades. We detected putative species complexes within two well sampled Palythoa clades (clades I and II), but species delimitation results were inconsistent in whether these clades contain multiple nominal species or represent a single variable species. Polyphyly in the broadly distributed species Palythoa tuberculosa and P. mutuki highlight the need for additional study. Consistency among nuclear and mitogenomic data-sets points to a lack of biological understanding of species boundaries among these zoantharians rather than limitations of the molecular markers. More complete taxonomic sampling of nominal species across the geographic ranges of distribution is necessary to resolve species boundaries and evolutionary histories among members of this genus.
... The simplicity of the zoanthid body plan makes morphology-based species identification quite challenging. Numerous morphological identification criteria have been used to identify phylogenetic signal ranging from colour, sphincter muscle anatomy 18 , tentacles number 19 , type and distribution of nematocysts 20 . In addition, differences in substrate preference, overall ecology 17 , biochemical profiles [21][22][23] and sequence divergence using various gene markers were also proposed as zoanthid identification criteria [24][25][26] . ...
Article
Full-text available
Coralligenous assemblages are among the most species-rich and vulnerable habitats of the Mediterranean Sea. Nevertheless, data on connectivity patterns on species inhabiting these habitats, crucial to define management and protection priorities, are largely lacking. Moreover, unreliable species-level taxonomy can confound ecological studies and mislead management strategies. In the northwestern Mediterranean two Parazoanthus axinellae morphotypes differing in size, color and preferred substrate are found in sympatry. In this study, we used COI and ITS sequence polymorphism to assess (1) the genetic divergence between the two morphotypes, (2) their connectivity patterns and (3) their phylogenetic position within the Parazoanthidae. Specimens of P. axinellae were sampled in 11 locations along the northwestern Mediterranean; in 6 locations, samples of the two morphotypes were collected in sympatry. Small genetic diversity and structure were found within morphotypes, while marked and consistent differentiation was detected between them. Moreover, the less widespread morphotype appeared to be closer to Pacific species as P. juanfernandezii and P. elongatus. Our findings confirmed the limited knowledge on Parazoanthus species complex, and how this gap can have important implication for the conservation strategies of this widespread and valuable genus in the Mediterranean Sea.
... 1.45s [30]. Cnidae classification generally followed England [31] and Ryland and Lancaster [32], while basitrichs and microbasic b-mastigophores were considered as the same type of nematocyst based on studies by Schmidt [33], Hidaka et al. [34], and Hidaka [35] and therefore these two types were pooled together. ...
... Cnidae: All cnidocyte categories previously reported in Zoantharia [32] were found, however holotrichs and p-mastigophores were particularly low in frequency in all examined tissues (tentacles, column, pharynx and mesenterial filaments); p-mastigophores were only found in mesenterial filaments, and holotrichs medium were found only in the pharynx. Spirocysts were absent in column and mesenterial filaments. ...
Article
Full-text available
Species of the anthozoan order Zoantharia (=Zoanthidea) are common components of subtropical and tropical shallow water coral reefs. Despite a long history of research on their species diversity in the Caribbean, many regions within this sea remain underexamined. One such region is the Dutch Caribbean, including the islands of St. Eustatius, St. Maarten, Saba, Aruba, Bonaire, and Curaçao, as well as the Saba Bank, for which no definitive species list exists. Here, combining examinations of specimens housed in the Naturalis Biodiversity Center collection with new specimens and records from field expeditions, we provide a list of zoantharian species found within the Dutch Caribbean. Our results demonstrate the presence at least 16 described species, including the newly described Parazoanthus atlanticus, and the additional potential presence of up to four undescribed species. These records of new and undescribed species demonstrate that although the zoantharian research history of the Caribbean is long, further discoveries remain to be found. In light of biodiversity loss and increasing anthropogenic pressure on declining coral reefs, documenting the diversity of zoantharians and other coral reef species to provide baseline data takes on a new urgency.
... Cnidae sizes were measured using ImageJ v1.45 s (Rasband, 2012). Although cnidae classification generally followed England (1991) and Ryland and Lancaster (2004), basitrichs and microbasic mastigophores were considered as the same type of nematocyst based on studies by Schmidt (1974), Hidaka et al. (1987), and Hidaka (1992), and therefore these two types were pooled together. ...
Article
The Family Hydrozoanthidae are macrocnemic zoantharians, however their phylogenetic position is closer to brachycnemic zoantharians than to other macrocnemic zoantharians. Previous studies have indicated the presence of undescribed Hydrozoanthidae species from various locations in the Indo-Pacific Ocean. In this study, two new Hydrozoanthidae species, Aenigmanthus segoi gen. n., sp. n. and Hydrozoanthus sils sp. n., are described from Japanese and Palauan waters based on combined morphological and molecular phylogenetic analyses utilizing multiple genetic markers. Additionally, Hydrozoanthidae consists of species with an obligate epizoic relationship with hydroids (Hydrozoanthus) and of species with facultative epizoic relationships (Aenigmanthus gen. n. and Terrazoanthus). Results of ancestral state reconstruction analyses indicate that Hydrozoanthus gained obligate epizoic relationships in their evolutionary history perhaps due to structural differences of host invertebrates.
... Several studies have attempted to find new morphological and histological characters that efficiently discriminate between zoantharian genera and species. Characters such as the cnidome (Herberts, 1972;Ryland and Lancaster, 2004) and sphincter muscle anatomy (Lwowsky, 1913) have traditionally been used, but have not proven to be efficient and applicable to zoantharians over a wide range of taxa (Sinniger et al., 2010). However, studies using molecular techniques in combination with morphological data have begun to bring some standardization and reassessment to zoantharian taxonomy, resulting in the creation of new taxa (Reimer et al., 2008a;Sinniger and Häussermann, 2009;Sinniger et al., 2010), the merging of other taxa (e.g., Reimer et al., 2006), and the identification of the most useful morphological characters to Zoantharia systematics by mapping these traits onto the molecular phylogeny of the group (Swain et al., 2016). ...
... Images were captured using Delta Pix-Invenio 5S scanner. Cnidae were classified according to the terminology used by Ryland and Lancaster (2004). The analyses of the cnidome are summarized in Table 1 where the ranges of length and width of nematocysts are reported. ...
Article
Full-text available
Zoantharians are a group of cnidarians that are often found in association with marine invertebrates, including corals, in shallow and deep-sea environments. However, little is known about deep-sea zoantharian taxonomy, specificity and nature of their associations with their coral hosts. In this study, analyses of molecular data (mtDNA COI, 16S and 12S rDNA) coupled with ecological and morphological characteristics were used to examine zoantharian specimens associated with cold-water corals at depths between 110 and 800 m from seamounts and island slopes in the Azores region. The zoantharians examined were found living in association with stylasterids, antipatharians and octocorals. From the collected specimens, four new species were identified: (1) Epizoanthus martinsae sp. n. associated with the antipatharian Leiopathes sp.; (2) Parazoanthus aliceae sp. n. associated with the stylasterid Errina dabneyi (Pourtalès, 1871); (3) Zibrowius alberti sp. n. associated with octocorals of the family Primnoida
... 14.1 and 14.2), in contrast to actiniarians, which have much more variety in their tentacle arrangements. Nematocysts (cnidae, stinging cells) are smaller and simpler than those of many sea anemones, with only seven nematocyst types reported from zoantharians (Ryland and Lancaster 2004). Additionally, as their common name indicates, most species (but not all) are colonial, with polyps connected by a common tissue, or coenenchyme. ...
Chapter
The order Zoantharia (Cnidaria: Hexacorallia) comprises benthic anthozoans found in most of the world’s marine ecosystems. Although historically understudied, research during the past 20 years has helped clarify our understanding of the diversity of this group. Much of this research on this group has originated from Japanese waters and has shown higher-level taxa (above genus) zoantharian diversity here to be among the highest recorded of any region in the world. Here, we introduce the overall species and higher-level zoantharian diversity as it is currently understood in Japan, and focus particularly on taxa that have been described or recorded from this country. Within Japan, taxonomic, phylogenetic, and ecological research has primarily focused on the southwestern Pacific Coast and the Ryukyu Archipelago, with little to no research performed in the Sea of Japan or in northern Japan. Additionally, results suggest that the deep sea, as well as other under-examined ecosystems such as rubble and muddy areas, still harbors much unknown zoantharian diversity. Even from relatively well-researched areas such as the Ryukyu Islands, data indicate that there are still many undescribed species. In the near future, more basic research efforts are needed before we can accurately estimate the diversity of Zoantharia. The methods and analyses used in recent studies of Japanese Zoantharia, as well as the new ideas proposed here, can be utilized in the near future in Japan and other marine regions to help us obtain a broader, more global understanding of zoantharian species distribution, biogeography, and diversity.
... Cnidae classification basically followed England (1991) and Ryland and Lancaster (2004). However, Schmidt (1974), Hidaka et al. (1987), Hidaka (1992), Fujii and Reimer (2011), and Montenegro et al. (2015) have referred to basitrichs and microbasic b-mastigophores as the same type of nematocysts and therefore in this study, these two types were pooled together. ...
Article
Full-text available
Epizoanthus species are generally found in association with other marine invertebrates such as hermit crabs and gastropods. Although Epizoanthus spp. are relatively common, there is limited information about their diversity and ecology due to their habitats or hosts, often being below the depths of SCUBA diving (>~50 m). In particular, the Epizoanthus fauna of the Indo-Pacific Ocean remains poorly understood. In this study, the diversity of Epizoanthus species associated with eunicid worm tubes from shallow waters in the Pacific Ocean we investigated using molecular analyses (mitochondrial cytochrome oxidase subunit 1 = COI, mitochondrial 16S ribosomal DNA = mt 16S-rDNA, nuclear internal transcribed spacer region of ribosomal DNA = ITS-rDNA) combined with morphological and ecological data. The combined data set leads us to describe two new species; Epizoanthus inazuma sp. n. and Epizoanthus beriber sp. n. Both new species are found in low-light environments: Epizoanthus inazuma sp. n. on mesophotic coral reef slopes and reef floors, or on the sides of overhangs; Epizoanthus beriber sp. n. has only been found in caves. Morphological characteristics of these two new species are very similar to Epizoanthus illoricatus Tischbierek, 1930 but the two new species are genetically distinct. Mesentery numbers and coloration of polyps may be useful diagnostic characteristics among eunicid-associated Epizoanthus species. These results demonstrate that there is high potential for other potentially undescribed zoantharian species, particularly in underwater cave habitats.
... Cnidae classification basically followed England (1991) and Ryland and Lancaster (2004). However, Schmidt (1974), Hidaka et al. (1987), Hidaka (1992), Fujii and Reimer (2011), and Montenegro et al. (2015) have referred to basitrichs and microbasic b-mastigophores as the same type of nematocysts and therefore in this study, these two types were pooled together. ...