Examinando por Autor "Herranz, Maria"

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A new case of kleptoplasty in animals: marine flatworms steal functional plastids from diatoms
(American Association for the Advancement of Science, 2019-07) Van Steenkiste, Niels W. L.; Stephenson, India; Herranz, Maria; Filip, Husnik; Keeling, P. J.; Leander, Brian S.
To date, sea slugs have been considered the only animals known to sequester functional algal plastids into their own cells, via a process called “kleptoplasty.” We report here, however, that endosymbionts in the marine flatworms Baicalellia solaris and Pogaina paranygulgus are isolated plastids stolen from diatoms. Ultrastructural data show that kleptoplasts are located within flatworm cells, while algal nuclei and other organelles are absent. Transcriptomic analysis and rbcL amplicons confirm the absence of algal nuclear mRNA and reveal that the plastids originate from different species of diatoms. Laboratory experiments demonstrated photosynthetic activity and short-term retention of kleptoplasts in starved worms. This lineage of flatworms represents the first known case of functional kleptoplasty involving diatoms and only the second known case of kleptoplasty across the entire tree of animals.
Comparative morphology of serotonergic‐like immunoreactive elements in the central nervous system of kinorhynchs (Kinorhyncha, Cyclorhagida).
(Wiley, 2013-03) Herranz, Maria; Pardos, Fernando; Boyle, Michael J.
Cycloneuralian taxa exhibit similar organ system architectures, providing informative characters of metazoan evolution, yet very few modern comparative descriptions of cellular and molecular homologies within and among those taxa are available. We immunolabeled and characterized elements of the serotonergic nervous system in the kinorhynchs Echinoderes spinifurca, Antygomonas paulae, and Zelinkaderes brightae using confocal laser scanning microscopy. Fluorescent markers targeting DNA were combined with observations of auto-fluorescent structures to guide interpretations of the internal and external anatomy in each species. Results show a common pattern of the central nervous system with a circumenteric brain divided into ring-shaped anterior and posterior neuronal somata and a central neuropil connected to a multi-stringed, longitudinal ventral nerve cord. Structural similarities and differences in the nervous systems of these species were observed and described, stressing the incomplete ring nature of the anterior region of the kinorhynch brain, the functional relationship between the brain and the movable introvert, and the number and arrangement of nerve strings and somata of the ventral nerve cord. The ventral cord ends in two ventrolateral cell bodies in E. spinifurca, and forms a terminal loop associated with a midterminal spine in A. paulae and Z. brightae. The possible functional and phylogenetic significance of these features and arrangements are discussed.
First account on kinorhynchs from Portugal, with the description of two new species: Echinoderes lusitanicus sp. nov. and E. reicherti sp. nov.
(Taylor and Francis, 2016-05) Neves, Ricardo C.; Sørensen, Martin V.; Herranz, Maria
The first exploration of the kinorhynch meiofauna in Portuguese marine waters has revealed the existence of two undescribed species of the cyclorhagid genus Echinoderes. In the present contribution we describe Echinoderes lusitanicus sp. nov. and Echinoderes reicherti sp. nov., both collected from subtidal regions of the coast of Algarve in the southernmost region of Portugal. Echinoderes lusitanicus sp. nov. is recognized by the presence of tubes on segment 2 in subdorsal and ventrolateral positions, on segment 5 in lateroventral positions, on segment 8 in lateral accessory positions, and on segment 10 in laterodorsal positions. Spines are present in middorsal position on segments 4 to 8, and in lateroventral positions on segments 8 and 9. The females have minute lateral terminal accessory spines. The second species, E. reicherti sp. nov., is characterized by tubes on segment 2 in subdorsal and ventrolateral positions, on segment 5 in lateroventral positions, and segment 8 in sublateral positions. In addition, the species possesses acicular spines in the middorsal position on segment 4, and in lateroventral positions on segments 6 to 9. Morphological aspects such as tube/spine pattern of the trunk or sexually dimorphic traits are discussed and compared with other Echinoderes species showing close resemblance.
Insights into mud dragon morphology (Kinorhyncha, Allomalorhagida): myoanatomy and neuroanatomy of Dracoderes abei and Pycnophyes ilyocryptus.
(Springer, 2020-07) Herranz, Maria; Sørensen, Martin V.; Park, Taeseo; Leander, Brian; Worsaae, Katrine
Comprehensive morphological investigations covering the diversity of metazoan lineages are needed to obtain a complete picture of organ system evolution. Despite the increased amount of studies on lesser-known phyla during the last decades, the gap in knowledge for these lineages is still remarkable. This is the case for kinorhynchs, or mud dragons, where only a few genera, mainly belonging to the major clade Cyclorhagida, have undergone detailed morphological examinations. Here, we explore the neuroanatomy and myoanatomy in the other major clade, Allomalorhagida, through studies of Dracoderes abei and Pycnophyes ilyocryptus by immunochemistry, CLSM, and computational 3D reconstruction. The current phylogenetic position of Dracoderes as a sister group to all the remaining allomalorhagids makes it a key taxon for understanding the evolution of organ systems within Kinorhyncha. Clear segmental arrangement of muscles and nerves was found in the trunk of D. abei and P. ilyocryptus, excluding modifications observed in the posteriormost segments. When comparing current and previous studies of allomalorhagids and cyclorhagids, the nervous system shows a conserved pattern across kinorhynchs, while the musculature shows significant variation among genera. Segmentation in kinorhynchs is restricted to the trunk, including mesoderm (muscles) and ectoderm derivated structures (nerves and glands). The nervous system shows a segmental arrangement in the first eight trunk segments, whereas the last three segments show some deviating arrangements most likely related to a post-hatching development of these segments. The presence of non-segmental trunk muscles is interpreted as adaptations for increased introvert motility and trunk flexibility.
Kinorhyncha from the Iberian Peninsula: new data from the first intensive sampling campaigns
(Magnolia Press, 2012-07-30) Herranz, Maria; Sánchez, Nuria; Benito, Jesús; Pardos, Fernando
Data are presented from the first intensive sampling of Kinorhyncha around the Iberian Peninsula over a 21-year periodfrom 1990 to 2011, from 81 sites mostly in less than 100 m water depth. Light-microscopic examination of approximately2000 specimens yielded 11 genera and 29 species, only 11 of which were previously recorded from peninsular waters. Thebalance comprises ten new species records for the peninsula and eight new species that are yet to be described. The mostspeciose genus is Echinoderes, with ten species, two of them new, followed by Pycnophyes (nine species, three new).There are two species of Antygomonas (one new), and one each for the genera Campyloderes, Centroderes, Condyloderes(one new), Dracoderes, Meristoderes, Semnoderes, Kinorhynchus (one new), and Paracentrophyes. The most ubiquitousspecies in the samples, appearing at nearly all localities was Pycnophyes dentatus, newly recorded for the Iberian Penin-sula and found at nearly all sampled localities and in high numbers. Echinoderes cantabricus, E. hispanicus and E. dujar-dinii also have a wide distribution along both Atlantic and Mediterranean coasts. Known information on diversity, biogeography and ecology (depth, sediment and abundance) is discussed.
Meristoderes gen. nov., a new kinorhynch genus, with the description of two new species and their implications for echinoderid phylogeny (Kinorhyncha: Cyclorhagida, Echinoderidae).
(Elsevier, 2012-08) Herranz, Maria; Thormar, Jonas; Benito, Jesús; Sánchez, Nuria; Pardos, Fernando
A new kinorhynch genus, Meristoderes gen. nov., and two new species from Spain and the Solomon Islands, respectively, are described. The new genus is distinguished from all other genera by the first segment consisting of a closed cuticular ring, and the second segment having partial tergosternal junctions, and a superficial midventral fold. This is a new cuticular configuration that may shed light into the phylogenetic relationships of echinoderid kinorhynchs. Meristoderes macracanthus gen. et sp. nov. from the Mediterranean coast of Spain is recognised by the presence of middorsal spines on segments 4, 6 and 8, ventrolateral tubules on segment 2, lateroventral tubules on segment 5, lateroventral spines on segments 6–9, lateral accessory tubules on segment 8, one pair of laterodorsal tubules on segment 10. Meristoderes galatheae sp. nov. from the Solomon Islands is recognized by having a middorsal spine on segment 4 only, ventrolateral tubules on segment 2, lateroventral tubules on segment 5, lateroventral spines on segments 6–9, lateral accessory tubules on segment 8 and subdorsal tubules on segment 10. Both species have a pattern of paraventral perforation site clusters on segments 3–9, with conspicuously long bracteate hairs from the posteriormost perforations sites on the segments 3–7 and 3–6, respectively. The new genus Meristoderes gen. nov. is included into the family Echinoderidae Bütschli, 1876 and appears closely related with the genera Cephalorhyncha Adrianov, 1999 and Echinoderes Claparède, 1863. The new information it provides is discussed to clarify the internal phylogeny of Echinoderidae. The terminology for cuticular characters in the overlapping area between consecutive segments is also standardized.
Microbiomes of microscopic marine invertebrates do not reveal signatures of phylosymbiosis
(Nature Research, 2022-05) Boscaro, Vittorio; Holt, Corey C.; Van Steenkiste, Niels W. L.; Herranz, Maria; Irwin, Nick A. T.; Álvarez-Campos, Patricia; Grzelak, Kasia; Holovachov, Oleksander; Kerbl, Alexandra; Mathur, Varsha; Okamoto, Noriko; Piercey, Rebecca S.; Worsaae, Katrine; Leander, Brian S.; Keeling, P. J.
Animals and microorganisms often establish close ecological relationships. However, much of our knowledge about animal microbiomes comes from two deeply studied groups: vertebrates and arthropods. To understand interactions on a broader scale of diversity, we characterized the bacterial microbiomes of close to 1,000 microscopic marine invertebrates from 21 phyla, spanning most of the remaining tree of metazoans. Samples were collected from five temperate and tropical locations covering three marine habitats (sediment, water column and intertidal macroalgae) and bacterial microbiomes were characterized using 16S ribosomal RNA gene sequencing. Our data show that, despite their size, these animals harbour bacterial communities that differ from those in the surrounding environment. Distantly related but coexisting invertebrates tend to share many of the same bacteria, suggesting that guilds of microorganisms preferentially associated with animals, but not tied to any specific host lineage, are the main drivers of the ecological relationship. Host identity is a minor factor shaping these microbiomes, which do not show the same correlation with host phylogeny, or ‘phylosymbiosis’, observed in many large animals. Hence, the current debate on the varying strength of phylosymbiosis within selected lineages should be reframed to account for the possibility that such a pattern might be the exception rather than the rule.
Myoanatomy of three aberrant kinorhynch species: similar but different?
(Springer, 2021-02) Herranz, Maria; Worsaae, Katrine; Park, Taeseo; Di Domenico, Maikon; Leander, Brian S.; Sørensen, Martin V.
Aberrant kinorhynchs show several modifications deviating from the typical kinorhynch body plan, including a modified introvert with very elongated and flexible scalids, a weakly developed neck, and a slender trunk with less distinct segmentation. How these aberrant external features are reflected in the inner anatomy and how their aberrant body plan evolved are not understood. Here, we provide a comprehensive and comparative myoanatomical study of three putatively, distantly related worm-like species: Cateria styx, Franciscideres kalenesos and Zelinkaderes yong. Despite the weak external segmentation of the trunk, the studied species show a distinct segmental arrangement of the musculature. However, this arrangement is shifted posteriorly with respect to the external segmentation, because the extremely thin and flexible cuticle is lacking the apodeme-like cuticular thickenings (pachycycli) where the longitudinal muscles usually attach. The muscular arrangement in the three species is overall similar, yet, C. styx shows most resemblance to the allomalorhagid F. kalenesos, whereas the cyclorhagid Z. yong differs in several ways. This suggests a closer relationship of C. styx to Allomalorhagida. Whereas most kinorhynchs prefer muddy sediments, both the allomalorhagid and cyclorhagid worm-like kinorhynchs are mainly found in sandy environments, suggesting that a flexible, slender body evolved at least twice independently as an adaptation to the interstitial environment.
Neuroanatomy of Mud dragons: a comprehensive view of the nervous system in Echinoderes (Kinorhyncha) by confocal laser scanning microscopy.
(Springer, 2019-10) Herranz, Maria; Leander, Brian S.; Pardos, Fernando; Boyle, Michael J.
Background: The Scalidophora (Kinorhyncha, Loricifera and Priapulida) have an important phylogenetic position as early branching ecdysozoans, yet the architecture of their nervous organ systems is notably underinvestigated. Without such information, and in the absence of a stable phylogenetic context, we are inhibited from producing adequate hypotheses about the evolution and diversification of ecdysozoan nervous systems. Here, we utilize confocal laser scanning microscopy to characterize serotonergic, tubulinergic and FMRFamidergic immunoreactivity patterns in a comparative neuroanatomical study with three species of Echinoderes, the most speciose, abundant and diverse genus within Kinorhyncha. Results: Neuroanatomy in Echinoderes as revealed by acetylated α-tubulin immunoreactivity includes a circumpharyngeal brain and ten neurite bundles in the head region that converge into five longitudinal nerves within the trunk. The ventral nerve cord is ganglionated, emerging from the brain with two connectives that converge in trunk segments 2–3, and diverge again within segment 8. The longitudinal nerves and ventral nerve cord are connected by two transverse neurites in segments 2–9. Differences among species correlate with the number, position and innervation of cuticular structures along the body. Patterns of serotoninergic and FMRFamidergic immunoreactivity correlate with the position of the brain neuropil and the ventral nerve cord. Distinct serotonergic and FMRFamidergic somata are associated with the brain neuropil and specific trunk segments along the ventral nerve cord. Conclusions: Neural architecture is highly conserved across all three species, suggesting that our results reveal a pattern that is common to more than 40%of the species within Kinorhyncha. The nervous system of Echinoderes is segmented along most of the trunk; however, posterior trunk segments exhibit modifications that are likely associated with sensorial, motor or reproductive functions. Although all kinorhynchs show some evidence of an externally segmented trunk, it is unclear whether external segmentation matches internal segmentation of nervous and muscular organ systems across Kinorhyncha, as we observed in Echinoderes. The neuroanatomical data provided in this study not only expand the limited knowledge on kinorhynch nervous systems but also establish a comparative morphological framework within Scalidophora that will support broader inferences about the evolution of neural architecture among the deepest branching lineages of the Ecdysozoa.
Phylogenomic analyses of mud dragons.
(Elsevier, 2022-03) Herranz, Maria; Stiller, Josefin; Worsaae, Katrine; Sørensen, Martin V.
Mud dragons (Kinorhyncha) are microscopic invertebrates, inhabiting marine sediments across the globe from intertidal to hadal depths. They are segmented, moulting animals like arthropods, but grouping with the unsegmented priapulans and loriciferans within Ecdysozoa. There are more than 300 species of kinorhynchs described within 31 genera and 11 families, however, their evolutionary relationships have so far only been investigated using morphology and a few molecular markers. Here we aim to resolve the relationships and classification of major clades within Kinorhyncha using transcriptomic data. In addition, we wish to revisit the position of three indistinctly segmented, aberrant genera in order to reconstruct the evolution of distinct segmentation within the group. We conducted a phylogenomic analysis of Kinorhyncha including 21 kinorhynch transcriptomes (of which 18 are new) representing 15 genera, and seven outgroups including priapulan, loriciferan, nematode and nematomorph transcriptomes. Results show a congruent and robust tree that supports the division of Kinorhyncha into two major clades: Cyclorhagida and Allomalorhagida. Cyclorhagida is composed of three subclades: Xenosomata, Kentrorhagata comb. nov. (including the aberrant Zelinkaderes) and Echinorhagata. Allomalorhagida is composed of two subclades: Pycnophyidae and Anomoirhaga nom. nov. Anomoirhaga nom. nov. accommodates the aberrant genera Cateria (previously nested within Cyclorhagida) and Franciscideres together with five additional genera. The distant and derived positions of the aberrant Zelinkaderes, Cateria and Franciscideres species suggest that their less distinct trunk segmentation evolved convergently, and that segmentation evolved among kinorhynch stem groups.
Phylogeny of Kinorhyncha Based on Morphology and Two Molecular Loci
(Public Library of Science, 2015-07) Sørensen, Martin V.; Dal Zotto, Mateo; Rho, Hyun Soo; Herranz, Maria; Sánchez, Nuria; Pardos, Fernando; Yamasaki, Hiroshi
The phylogeny of Kinorhyncha was analyzed using morphology and the molecular loci 18S rRNA and 28S rRNA. The different datasets were analyzed separately and in combination, using maximum likelihood and Bayesian Inference. Bayesian inference of molecular sequence data in combination with morphology supported the division of Kinorhyncha into two major clades: Cyclorhagida comb. nov. and Allomalorhagida nom. nov. The latter clade represents a new kinorhynch class, and accommodates Dracoderes, Franciscideres, a yet undescribed genus which is closely related with Franciscideres, and the traditional homalorhagid genera. Homalorhagid monophyly was not supported by any analyses with molecular sequence data included. Analysis of the combined molecular and morphological data furthermore supported a cyclorhagid clade which included all traditional cyclorhagid taxa, except Dracoderes that no longer should be considered a cyclorhagid genus. Accordingly, Cyclorhagida is divided into three main lineages: Echinoderidae, Campyloderidae, and a large clade, ‘Kentrorhagata’, which except for species of Campyloderes, includes all species with a midterminal spine present in adult individuals. Maximum likelihood analysis of the combined datasets produced a rather unresolved tree that was not regarded in the following discussion. Results of the analyses with only molecular sequence data included were incongruent at different points. However, common for all analyses was the support of several major clades, i.e., Campyloderidae, Kentrorhagata, Echinoderidae, Dracoderidae, Pycnophyidae, and a clade with Paracentrophyes + New Genus and Franciscideres (in those analyses where the latter was included). All molecular analyses including 18S rRNA sequence data furthermore supported monophyly of Allomalorhagida. Cyclorhagid monophyly was only supported in analyses of combined 18S rRNA and 28S rRNA (both ML and BI), and only in a restricted dataset where taxa with incomplete information from 28S rRNA had been omitted. Analysis of the morphological data produced results that were similar with those from the combined molecular and morphological analysis. E.g., the morphological data also supported exclusion of Dracoderes from Cyclorhagida. The main differences between the morphological analysis and analyses based on the combined datasets include: 1) Homalorhagida appears as monophyletic in the morphological tree only, 2) the morphological analyses position Franciscideres and the new genus within Cyclorhagida near Zelinkaderidae and Cateriidae, whereas analyses including molecular data place the two genera inside Allomalorhagida, and 3) species of Campyloderes appear in a basal trichotomy within Kentrorhagata in the morphological tree, whereas analysis of the combined datasets places species of Campyloderes as a sister clade to Echinoderidae and Kentrorhagata.
Redescription of Echinoderes ohtsukai Yamasaki and Kajihara, 2012 and E. kozloffi Higgins 1977 from the northeastern Pacific coast, including the first report of a potential invasive species of kinorhynch
(Elsevier, 2016-11) Herranz, Maria; Leander, Brian
Although the dispersal ability of kinorhynchs is known to be limited, the distribution of certain kinorhynch species appears to extend over vast geographical areas. Combining molecular phylogenetic data with biogeographical investigations can test this paradox by discerning cryptic species with restricted distributions from species with potentially large geographical distributions. In this paper, we (1) redescribe two species of kinorhynchs (Echinoderes ohtsukai and E. kozloffi) found in the northeastern Pacific Ocean using molecular and morphological data and (2) provide the first evidence for a disjunct geographical distribution in kinorhynchs that is consistent with the introduction of an invasive species. Although we collected E. ohtsukai from the northeastern Pacific Ocean (British Columbia, Canada), this species was originally described from Japan. We demonstrated that specimens of E. ohtsukai collected from Japan and British Columbia have identical DNA sequences for the mitochondrial cytochrome c oxidase subunit 1 (COI) gene. These results are most consistent with a recent introduction of this species into one of the habitats on the opposite side of the Pacific Ocean through human-mediated dispersal.
Revisiting kinorhynch segmentation: variation of segmental patterns in the nervous system of three aberrant species
(BMC, 2021-10) Herranz, Maria; Park, Taeseo; Di Domenico, Maikon; Leander, Brian; Sørensen, Martin V.; Worsaae, Katrine
Background: Kinorhynch segmentation differs from the patterns found in Chordata, Arthropoda and Annelida which have coeloms and circulatory systems. Due to these differences and their obsolete status as ‘Aschelminthes’, the microscopic kinorhynchs are often not acknowledged as segmented bilaterians. Yet, morphological studies have shown a conserved segmental arrangement of ectodermal and mesodermal organ systems with spatial correspondence along the anterior-posterior axis. However, a few aberrant kinorhynch lineages present a worm-like body plan with thin cuticle and less distinct segmentation, and thus their study may aid to shed new light on the evolution of segmental patterns within Kinorhyncha. Results: Here we found the nervous system in the aberrant Cateria styx and Franciscideres kalenesos to be clearly segmental, and similar to those of non-aberrant kinorhynchs; hereby not mirroring their otherwise aberrant and posteriorly shifted myoanatomy. In Zelinkaderes yong, however, the segmental arrangement of the nervous system is also shifted posteriorly and misaligned with respect to the cuticular segmentation. Conclusions: The morphological disparity together with the distant phylogenetic positions of F. kalenesos, C. styx and Z. yong support a convergent origin of aberrant appearances and segmental mismatches within Kinorhyncha.