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Revista de BiologÃa Tropical, ISSN: 2215-2075, Vol. 72(S1): e58993, marzo 2024 (Publicado Mar. 01, 2024)
Study of histopathology on Arbacia lixula (Arbaciidae: Arbacioida)
and Paracentrotus lividus (Parachinidae: Camarodonta)
with bald sea urchin disease symptoms in Gran Canaria Island, Spain
Raibel Núñez-González1*; https://orcid.org/0000-0001-6088-3042
MarÃa José Caballero2; https://orcid.org/0000-0002-2575-0997
Daniel Padilla2; https://orcid.org/0000-0002-6678-5029
José Luis MartÃn Barrasa2, 3; https://orcid.org/0000-0002-3280-9838
José Juan Castro Hernández1; https://orcid.org/0000-0001-9577-5957
1. Instituto Universitario EcoAqua, University of Las Palmas de Gran Canaria, 35017 Tafira, Spain;
raibel.nunez101@alu.ulpgc.es (*Correspondence), jose.castro@ulpgc.es
2. Institute for Animal Health and Food Safety (IUSA), Veterinary School, University of Las Palmas de Gran Canaria,
35413 Arucas, Spain; mariajose.caballero@ulpgc.es, daniel.padilla@ulpgc.es, joseluis.martin@ulpgc.es
3. Experimental Animal Facility, Research Unit, Hospital Universitario de Gran Canaria, Dr. NegrÃn, Las Palmas de Gran
Canaria, Spain.
Received 27-VI-2023. Corrected 06-XII-2023. Accepted 03-I-2024.
ABSTRACT
Introduction: Sea urchin diseases have been documented in several locations worldwide, with reported occur-
rences of bacterial, protozoan, fungal, and algal infections.
Objective: This study aimed to investigate pathogen agents in populations of Arbacia lixula and Paracentrotus
lividus along the coast of Gran Canaria Island (Central-East Atlantic, Spain).
Methods: Sampling was conducted at San Cristobal beach, on the Northeast side of the island, where sea urchins
were manually collected from depths of 1-3 m during June, July, and October 2022. Swab samples were taken
from the external and internal areas of the lesions and cultured on various media plates.
Results: Eight different pathogen agents, including bacteria and fungi, were identified, with Vibrio alginolyticus
being the most frequently observed bacteria in all diseased sea urchin samples. Additionally, ciliated protozoans
were found within the tests, potentially acting as opportunistic parasites.
Conclusions: This research provides a unique perspective on bald sea urchin disease by identifying a significant
number of associated pathogens, including Candida, previously unreported in diseased organisms. Furthermore,
the study highlights the presence of an inflammatory response in tissues with bacterial colonies, offering crucial
insights into understanding this sea urchin disease.
Key words: rocky shore; Vibrio; sea urchin mortality; Canary Islands; Webbnesia.
RESUMEN
Estudio de histopatologÃa en Arbacia lixula (Arbaciidae: Arbacioida) y Paracentrotus lividus
(Parachinidae: Camarodonta) con sÃntomas de la enfermedad del erizo desnudo
en la Isla de Gran Canaria, España
Introducción: Las enfermedades en los erizos de mar han sido descritas en muchas localidades alrededor del
mundo, y se han asociado con la presencia de infecciones por bacterias, protozoarios, hongos y algas.
https://doi.org/10.15517/rev.biol.trop..v72iS1.58993
SUPPLEMENT
2Revista de BiologÃa Tropical, ISSN: 2215-2075 Vol. 72(S1): e58993, marzo 2024 (Publicado Mar. 01, 2024)
INTRODUCTION
Sea urchin diseases have been described
around the globe, particularly those that caused
several mass mortalities, including those that
occurred in the 80´ with Diadema antillarum
(Philippi, 1845) in the Caribbean Sea (Lessios,
1988), and Strongylocentrotus droebachiensis
(O.F. Müller, 1776) in Nova Scotia, Canada
(Jones et al., 1985). In both cases, the infection
agents were not deeply described. In addition,
sea urchin diseases have been reported between
2001 and 2020 in some regions of Webbnesia:
Madeira (Portugal), and Tenerife and La Palma
in Canary Islands (Spain), mainly in Diadema
africanum (RodrÃguez, Hernández, Clemente &
Coppard, 2013), but in other species as Paracen-
trotus lividus (Lamarck, 1816), Arbacia lixula
(Linnaeus, 1758), and Sphaerechinus granularis
(Lamarck, 1816) (Clemente et al., 2014; Dyková
et al., 2011; Girard et al., 2011; Gizzi et al., 2020;
Hernández et al., 2020; Salazar-Forero et al.,
2022), and it is important to highlight that there
are no reports of mass mortalities or diseases in
Gran Canaria Island.
In recent times, some authors have report-
ed the pathogenic action of different infec-
tious agents in sea urchins, such as bacteria,
protozoan, fungi, and algae, being bacteria the
most common agent appearing in all diseases
(Dyková et al., 2011; Gizzi et al., 2020; Grech
et al., 2019; Grech et al., 2022; Hernández et
al., 2020; Hewson et al., 2023; Jangoux, 1987;
Salazar-Forero et al., 2022; Shaw et al., 2024;
Shimizu et al., 1995; Wang et al., 2013b; Wang
et al., 2023). In the case of bacteria, one of the
groups most frequently described in marine
habitats is that of the Vibrio genus, which
increases its concentration during the tempera-
ture rise and produces blooms (Mira-Gutiérrez
& GarcÃa-Martos, 1998). Within the Vibrio
genus, Vibrio alginolyticus (Miyamoto et al.,
1961) is the most abundant and halotolerant
species in temperate marine ecosystems (Mira-
Gutiérrez & GarcÃa-Martos, 1998).
Several authors around the globe have
reported Vibrio spp. in diseased tissues of
some sea urchin’s species, such as D. africa-
num, Strongylocentrotus intermedius (A. Agas-
siz, 1864), and P. lividus (Becker et al., 2008;
Clemente et al., 2014; Gizzi et al., 2020; Grech
et al., 2022; Salazar-Forero et al., 2022; Shimizu
et al., 1995; Wang, Chang et al., 2013; Wang,
Feng et al., 2013; Wang et al., 2023). However,
there is some controversy because the same
bacteria are isolated from healthy sea urchins,
leading to their classification as opportunistic
rather than primary pathogens. For this rea-
son, it is essential to resort to histopathologi-
cal studies to visualize tissue alterations and
to complement the diagnosis of this disease
(Virwani et al., 2021).
Different protozoan species have been
described in some echinoderms as infection
Objetivo: Este estudio tuvo como finalidad investigar sobre los agentes patógenos que afectan a las poblaciones de
Arbacia lixula y Paracentrotus lividus a lo largo de la costa de la Isla de Gran Canaria (Atlántico Centro-Oriental,
España).
Métodos: El muestreo fue llevado a cabo en la playa de San Cristóbal, al noreste de la isla, dónde los organismos
fueron capturados entre 1-3 metros de profundidad, durante junio, julio y octubre del año 2022. Se tomaron
muestras en la zona interna y externa de la lesión en cada organismo, y se cultivaron en varios medios de cultivo.
Resultados: Fueron identificados ocho agentes patógenos diferentes, incluyendo bacterias y hongos, y sien-
do Vibrio alginolyticus la bacteria más frecuentemente observada en todas las muestras de erizos enfermos.
Además, se observaron protozoarios ciliados dentro de los caparazones, actuando potencialmente como parásitos
oportunistas.
Conclusiones: Esta investigación proporciona una perspectiva única sobre la enfermedad del erizo desnudo
al identificar un número significativo de patógenos asociados, incluida Candida, que no se habÃa reportado
previamente en organismos enfermos. Además, el estudio destaca la presencia de una respuesta inflamatoria
en tejidos con colonias bacterianas, lo que ofrece información crucial para comprender esta enfermedad de los
erizos de mar.
Palabras clave: costas rocosas; Vibrio; mortalidad de erizos de mar; Islas Canarias; Webbnesia.
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Revista de BiologÃa Tropical, ISSN: 2215-2075, Vol. 72(S1): e58993, marzo 2024 (Publicado Mar. 01, 2024)
agents. For example, Hernández et al. (2020)
reported that the mass mortality events of D.
africanum in Madeira and the Canary Islands
were associated with anomalous southwest
storms that resuspended bottom sediment and
favored the appearance of paramoebas pro-
moting paramoebiasis. Also, Scheibling and
Lauzon-Guay (2010) described how the amoe-
bic disease has been producing sea urchin mas-
sive mortalities in the North Atlantic Ocean,
because of intense tropical cyclones near warm
coastlines, which has facilitated the spread of
the disease. Furthermore, Jangoux (1987) in
his echinoderm diseases review described the
presence of the ciliate Orchitophrya stellarum
(Cépède, 1907) which parasites the gonads
of Asterias rubens (Linnaeus, 1758). Finally,
Virwani et al. (2021) reported the presence
of ciliates and encysted metazoan parasites in
diseased test tissues on Tripneustes ventricosus
(Lamarck, 1816) from St. Kitts, Caribbean Sea.
It is crucial to emphasize that certain authors
have associated the increase of pathogen bac-
teria with the rising seawater temperature.
Indeed, the collaborative work of Garrabou et
al. (2022) showed that the increase in seawater
temperature in the Mediterranean Sea between
2015–2019 is the cause behind the mass mortal-
ity of 23 taxa and seven phyla, with the shallow
water echinoderms, distributed between 0 and
10 m depth, included in this list.
In this context, this work aimed to char-
acterize the infection agents and describe the
histopathology and disease observed in Arbacia
lixula and Paracentrotus lividus populations on
the coast of Gran Canaria Island (Northeast
Atlantic, Spain).
MATERIALS AND METHODS
Study area: This study was conducted on
San Cristobal beach, on the northeast coast of
Gran Canaria Island (Canary Islands, Spain;
27º45´N 15º45´W) (Fig. 1). This urban beach
of the capital city of Las Palmas of Gran Canar-
ia, the most populated area of the island, is a
highly anthropogenic coast close to the La Luz
harbor, one of the most important ports in
Fig. 1. San Cristobal beach location, where sea urchins (Paracentrotus lividus and Arbacia lixula) were collected (Gran
Canaria Island, Spain).