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Expansion of the genus Massinium (Holothuroidea: Thyonidae)

to the American continent and description of a new species

Francisco A. Solís-Marín

Alfredo Laguarda-Figueras

Carlos A. Conejeros-Vargas

Andrea A. Caballero-Ochoa

3, 4

Alicia Durán-González

1. Colección Nacional de Equinodermos “Dra. Ma. Elena Caso Muñoz”, Laboratorio de Sistemática y Ecología de

Equinodermos, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Coyoacán,

Ciudad de México, México; fasolis@cmarl.unam.mx (*Correspondence), laguarda@cmarl.unam.mx,

aliciad@cmarl.unam.mx

2. Posgrado en Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Av. Ciudad Universitaria,

Coyoacán, Ciudad de México, México; conejeros@ciencias.unam.mx

3. Facultad de Ciencias, Universidad Nacional Autónoma de México. Circuito exterior s/n, Ciudad de México, México;

a.caballero.ochoa@ciencias.unam.mx

4. Posgrado en Ciencias Biológicas, Universidad Nacional Autónoma de México, Av. Ciudad Universitaria 3000,

C.P. 04510, Coyoacán, Ciudad de México, México.

Received 07-VII-2020. Corrected 25-VIII-2020. Accepted 06-XI-2020.

ABSTRACT

Introduction: The genus Massinium includes 11 species, most from the Indo Pacific Ocean, and had not previ-

ously being reported from the American continent. Objective: To present the new record of the genus Massinium

and describe a new species of this genus. Methods: Material collection was done by SCUBA-diving to depths of

a maximum of 9 m. Results: Massinium ocumichoensis sp. nov. is described from seven specimens that extends

the range of the genus to the American continent (Guerrero, Michoacan and Jalisco, Mexico). The new species

lives in sandy-rocky substrata, from 2 to 16 m deep. It is distinguished from its congeneric species by a combina-

tion of morphological characters: mid-dorsal slightly bigger pseudobuttons (40-60 μm), and tables in the body

wall. A taxonomic key for distinguishing the species of Massinium is provided. Conclusions: The geographic

range of the genus Massinium is extended to the Mexican Pacific with M. ocumichoensis sp. nov.

Key words: Echinodermata; Dendrochirotida; biodiversity; taxonomy; new record.

Solís-Marín, F.A., Laguarda-Figueras, A., Conejeros-

Vargas, C.A., Caballero-Ochoa, A.A., & Durán-

González, A. (2021). Expansion of the genus

Massinium (Holothuroidea: Thyonidae) to the

American continent and description of a new species.

Revista de Biología Tropical, 69(S1), 304-311. DOI

10.15517/rbt.v69iSuppl.1.46363

The order Dendrochirotida is the most

diverse holothuroid order of the world (Prata

& Christoffersen, 2016). It is represented by

the families Cucumariidae, Phyllophoridae,

Psolidae, Sclerodactylidae and Thyonidae in

the Mexican Pacific waters (Solís-Marín et

al., 2013). The family Thyonidae Panning,

1949, sensu Smirnov (2012) is composed of

Dendrochirotida with 10-20 tentacles, tube

feet scattered all over the body or restricted

to the radii, the calcareous ring is segmented,

the ossicles are tables with two or four pillars

and/or plates; sometimes baskets present. The

family includes four subfamilies: Thyoninae,

Thyonininae, Hemithyoninae and Semperiel-

linae (Smirnov, 2012; Thandar, 2017). The

DOI 10.15517/rbt.v69iSuppl.1.46363

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genus Massinium Samyn & Thandar, 2003

was included in the subfamily Semperiellinae

Heding & Panning, 1954 by Thandar (2017),

this genus was erected to accommodate sea

cucumbers which have the posterior processes

of their tubular calcareous ring distally joined

to form a ring-like structure around the esopha-

gus and body wall with granuliform rods and/or

rosette-shaped deposits and tables. Samyn and

Thandar (2003) and Samyn, Thandar, and Van-

denSpiegel (2010) included six species in the

genus: the Australian endemic M. granulosum

Samyn, Thandar and VandenSpiegel, 2010; the

New Caledonian endemic M. albicans Samyn,

Thandar and VandenSpiegel, 2010; the central

Indo-Pacific M. magnum (Ludwig, 1882), the

southern African endemics M. arthroproces-

sum (Thandar, 1989), M. maculosum Samyn &

Thandar, 2003 and M. dissimilis (Cherbonnier,

1988) from Madagascar. Later O’Loughlin,

Barmos, and VandenSpiegel (2012) included

three more Australian endemic species: M.

melanieae O’Loughlin in O’Loughlin et al.

(2012), M. vimsi O’Loughlin in O’Loughlin

et al. (2012) and M. watsonae O’Loughlin

in O’Loughlin et al. (2012). Two years later

O’Loughlin, Mackenzie, and VandenSpie-

gel (2014) included the Australian endemics

M. bonapartum O’Loughlin in O’Loughlin

et al. (2014) and M. keesingi O’Loughlin in

O’Loughlin et al. (2014). Today Massinium

includes 11 species, most from the Indo Pacific

Ocean (WoRMS, 2020).

There are no previous records of the genus

on the American continent waters. Seven speci-

mens were collected along the Mexican Pacif-

ic, representing a new record of the genus and

a new species.

MATERIALS AND METHODS

During recent surveys of the echinoderm

fauna of the Mexican Pacific, seven specimens

belonging to this new species were found.

Collection was done by SCUBA-diving to

depths of a maximum of 9 m. Specimens were

anaesthetized in a solution of 4 % magnesium

chloride and seawater. After properly labelled,

fixation of the specimens was done with 70 %

ethyl alcohol. All measurements were obtained

from fixed specimens. Ossicles were extracted

from the body wall (anterior, medium and pos-

terior region) introvert and tentacles. The tissue

was dissolved in fresh household bleach (5-6.5

%) in centrifuge tubes. After centrifugation at

1 000 rpm for 10 min, bleach was pipetted off

and the ossicles were rinsed and centrifuged

with distilled water that was pipetted off after-

wards. The same process was done with 70,

80, and 95 % ethanol. Absolute ethanol was

added to the ossicles, and finally a small aliquot

was taken and placed to dry on a cylindrical

double-coated conductive carbon tape stub.

Then it was sputter coated with gold 2.5 kV

in the ionizer Polaron E3000 for 3 min and

photographed using a Hitachi S-2460N scan-

ning electron microscope (SEM). Photographs

of the holotype specimen were taken using

a Leica DFC490 digital camera, and a Leica

Z16 APOA stereomicroscope. The examined

material is deposited in the ICML-UNAM

and LACM. Zoobank link: http://zoobank.org/

urn:lsid:zoobank.org:pub:1C0A2F30-8065-

4C9C-855B-9FFD681C5A7D

Abbreviations: ICML-UNAM: Colec-

cion Nacional de Equinodermos, Instituto de

Ciencias del Mar y Limnologia, Universidad

Nacional Autonoma de Mexico, Mexico City.

LACM: Natural History Museum, Los Ange-

les County Museum, Los Angeles, California,

USA. TL: Total Length.

ANALYSIS

Order Dendrochirotida Grube, 1840

Family Thyonidae Panning, 1949

(sensu Smirnov, 2012)

Diagnosis: Dendrochirotida with 10-20

tentacles. Tube feet scattered all over body

or restricted to the radii. Calcareous ring

segmented. Ring often tubular, forked pro-

cesses of radial segments long, prominent.

Inter-radial segments often strongly elon-

gated basally fused with processes of radial

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segments; both calcareous ring segments, and

processes subdivided into many pieces. Ossi-

cles: tables with two or four pillars and/or

plates; sometimes baskets present (modified

from Smirnov, 2012).

Subfamily Semperiellinae

Heding & Panning, 1954

Diagnosis: (modified from O’Loughlin et

al., 2012 and Smirnov, 2012). A polytentaculate

subfamily of Thyonidae with 15-20 tentacles.

Tube feet lying along radii or scattered over

entire body. Calcareous ring well developed,

often tubular, radial and inter-radial plates

always broken into a mosaic of pieces, posteri-

or processes of radial and often the inter-radial

plates sub-divided, and processes of radial and

sometimes the inter-radial plates joining pos-

teriorly, the latter forming a ribbon-like ring

surrounding the water vascular ring. Body wall

ossicles 2-4 pillared tables or their derivatives.

Genus Massinium Samyn & Thandar, 2003

Diagnosis: (modified from O’Loughlin

et al., 2014). Slim, elongated body, some-

times semi-spherical forms; anterior and pos-

terior parts of the body narrow, with oral and

anal dorsal orientations; 20 dendritic tentacles

arranged in two circles of ten large outer and

ten small inner (proximal peri-oral); calcareous

ring elongated, tubular, with both radial and

inter-radial plates fragmented into a mosaic

of pieces, and posterior prolongations linked

distally to form inter-radial oval non-calcified

spaces beneath the water vascular ring; polian

vesicles from one to four; ossicles variably

include granuliform rods, rosettes, pseudobut-

tons and tables; table spires with one or two or

three or reduced pillars.

Type especies: Massinium maculo-

sum Samyn & Thandar, 2003 (by original

designation).

Massinium ocumichoensis sp. nov.

Fig. 1A, 1B, 1C, Fig. 2A, 2B, 2C,

2D, 2E, 2F, 2G, 2H, 2I

Type specimen: Holotype, ICML-UNAM

10078, Faro de Bucerias, Aquila, Michoacan,

Mexico, Pacific Ocean (18°21’12.21” N &

103°31’03.06” W), 5 m, sandy-rocky bottom,

January 8

2013, Coll. Solis-Marin, F. A.,

Hooker, Y., Arriaga-Ochoa. J. A., Hernandez, Q.

Type locality: Faro de Bucerias, Michoac-

an, Mexico, Pacific Ocean (18°21’12.49” N &

103°31’03.80” W), 5 m, sandy-rocky bottom,

January 8

2012.

Other type material: Paratypes, one spec-

imen, ICML-UNAM 18367, same data as

the holotype; one specimen, LACM E.2016-

15.1, Isla Cocinas, Chamela Bay, Jalisco,

Mexico, Pacific Ocean (19°32’47.20’’ N &

105°06’34.20’’ W), 7 m, sandy-rocky bottom,

November 23 2016, Coll. Solis-Marin, F. A.,

Caballero-Ochoa A. A., Conejeros-Vargas, C.

A., Marquez-Borras, F. and Ayala-Aguilera,

P. A.; one specimen, ICML-UNAM 8504,

La Cagada, Acapulco Bay, Guerrero, Mex-

ico, Pacific Ocean (16°49’28.50” N &

99°55’03.62” W), 9 m, sandy-rocky bottom,

May 26 2006, Coll. Solis-Marin, F. A., Honey-

Escandon, M.; one specimen, ICML-UNAM

8952, Isla Cocinas, Chamela Bay, Jalisco,

Mexico, Pacific Ocean (19°33’45.40” N &

105°06’32.90” W), 2 m, sandy-rocky bottom,

November 17 2008, Coll. Solis-Marin, F. A.,

Honey-Escandon, M.; one specimen, ICML-

UNAM 11912, Isla Pajarera, external area,

Chamela Bay, Jalisco, Mexico, Pacific Ocean

(19°33’27.70” N & 105°07’0.60” W), 16 m,

sandy-rocky bottom, November 13 2013, Coll.

Solis-Marin, F. A., Arriaga-Ochoa, J. A., Her-

nandez, Q., Pineda-Enriquez, T., Caballero-

Ochoa, A. A.; 2 specimens, ICML-UNAM

12627, Playa Caleta, Acapulco Bay, Guerrero,

Mexico (16°49’49.16” N & 99°54’03.88” W),

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4.5 m, sandy-rocky bottom, November 16

2015, Coll. Solis-Marin, F. A., Hernández, Q.,

Parada, T.; Márquez Borrás, F., Teyssier. E.;

one specimen, ICML-UNAM 13144, Balandra

Bay, Gulf of California, Baja California Sur,

Mexico (24°19’26.94” N & 110°19’34.46”

W), 1 m, sandy-rocky bottom, March 23 2017,

Coll. Solis-Marin, F. A., Caballero-Ochoa, A.

A., Conejeros-Vargas, C. A., Ayala Aguirre P.,

Calderón-Gutiérrez, F.; one specimen, ICML-

UNAM 18368, Isla Cocinas, Chamela Bay,

Jalisco, Mexico, Pacific Ocean (19°32’46” N

& 105°06’32” W), 4-5 m, sandy-rocky bottom,

November 15 2010, Coll. Solis-Marin, F. A.,

Honey-Escandon, M.

Diagnosis: Small-sized (60-74 mm TL),

U-shaped thyonid with bloated mid-body and

relatively short anterior and posterior ends.

Anus surrounded by ten small papillae, vari-

ously developed. Tube feet scattered over entire

body. Ossicles of body wall two pillared tables

and pseudobuttons, often with minute perfora-

tions. Introvert ossicles include pseudobuttons,

tables and rosettes. Tentacles of outer ring with

smooth, slightly curved rods, perforated at the

ends, external tips of the outer tentacles ring

devoid of ossicles, tentacles of inner ring with

rods and rosettes. Body color off-white to grey,

mottled with dark brown, sometimes black;

tentacle dendritic branches black, trunks trans-

parent with black moles.

Etymology: The name ocumichoensis

refers to Ocumicho, Michoacan (same state as

the type locality), a famous small town where

folk artisans create colorful clay magical devils

and beasts.

Description of holotype: Specimen entire,

well preserved, dissected (Fig. 1A). Mouth

anterior, anus posterior, slightly developed anal

papillae; body wall firm, leathery, rather thin

(0.8-1 mm), slightly rough to the touch. Body

Fig. 1. Massinium ocumichoensis sp. nov. A. External, lateral view of holotype ICML-UNAM 10078. B. Tentacle crown of

the holotype in situ. C. Calcareous ring. R. Radial plates. I. Inter-radial plate. M. Madreporite. SC. Stone canal. PV. Polian

vesicles. E. Esophagus.

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form cylindrical, slightly contracted, bloated,

with narrow anterior and posterior ends. Intro-

vert well extended, attached to the main body.

Length of specimen along ventral surface 74

mm; along dorsal surface 64 mm; height of

mid-body approximately 18 mm; anterior and

posterior ends approximately 20 and 18 mm

long; introvert 8 mm long. Coloration of body

and introvert beige brown with brown small

moles. Tube feet of body wall beige, numer-

ous, small, mostly retracted, uniformly scat-

tered over entire body, very small suckers;

close cover ventrally and around mouth and

anus; tube feet of introvert brownish, darker

proximally, aligned in radial areas in two well-

defined rows, absent in distal 3 mm. Tentacles

20, ten large, ten small, arranged in two rows

(Fig. 1B); outer tentacles, when alive, 35-40

mm long, black tips, middle part shaft whitish

with black moles; when preserved the tentacles

are highly contracted (9 mm). Calcareous ring

short (10 mm), tubular, composite; both radial

and interradial plates broken into a mosaic;

radial plates elongated, with a shallow cen-

tral notch, central part constricted and poste-

rior part divided in two short tails, inter-radial

plates triangular pointed anteriorly, large oval

un-calcified posterior section closed distally

by non-calcified link; one madreporite, well

calcified, stone canal scalloped and attached

to one extension of the interradial plate poste-

rior processes of the calcareous ring (Fig. 1C);

four polian vesicles (Fig. 1C); respiratory trees

extending the length of the coelom.

Ossicles in mid-body wall are large pseu-

dobuttons (40-60 μm) (Fig. 2A), and tables

sparse dorsally (Fig. 2B) table disc outlines

irregularly round, typically four larger central

and some small outer perforations, margin

smooth or spinous, discs up to 42 μm wide;

tables frequently with two pillars, low or

residual, few thick blunt apical spines. Anterior

and posterior body wall areas with small pseu-

dobuttons (15-30 μm) (Fig. 2A). Oral disc with

abundant tables with discs up to 35 μm long,

irregularly oval, many perforations, margins

smooth; spires short, up to 10 μm tall, two pil-

lars, rarely single, one to two median perfora-

tions, short apical spines typically splayed (Fig.

2B). Peri-anal body wall with abundant tables

similar to those in the mid-body wall; some

rods with distal perforations, rods up to 80 μm

long; anal papillae with small multi-layered

anal scales about 45 μm long. Introvert with

pseudobuttons, tables and rosettes (Fig. 2C,

2D, 2E). Tube feet with endplates, up to 40-45

μm diameters, margin thick (Fig. 2F), with

support ossicles as smooth rods with perforated

ends (Fig. 2G). Tentacles of outer ring with

abundant simple slightly curved rods perfo-

rated at the ends and granuliform rod ossicles;

simple rods up to 50 μm long with perforated

ends; granuliform rods up to 55 μm long with

short rod widened distally with many small

perforations created by dendritic branch fusing

(Fig. 2H); abundant well-elaborated rosettes

(Fig. 2I). External tips of the outer tentacles

ring devoid of ossicles, tentacles of inner ring

with rods and rosettes.

Body live color off-white to grey, mottled

with dark brown, sometimes black; tentacle

dendritic branches black, trunks transparent

with black moles; color preserved off white

to pale beige, tube feet beige, tentacles black,

trunks off-beige to black (Fig. 1B).

Description of paratypes: The paratypes

are from 40 to 74 mm long. The ossicles of the

body wall and other parts of the body are simi-

lar to those in the holotype. The calcareous ring

in 40-50 mm TL specimens is small and the

mosaic is very difficult to observe. Preserved

specimens color varies from light to dark grey.

Some specimens have light beige body and

beige to brown tube feet.

Distribution and habitat: Massinium

ocumichoensis sp. nov. have been recorded in

the Mexican Pacific at Balandra Bay, Gulf of

California, Baja California Sur; Isla Cocinas,

Isla Pajarera, Chamela Bay, Jalisco; Faro de

Bucerias, Aquila, Michoacan and Acapulco

Bay, Guerrero, Mexico. Occur in sandy-rocky

substrata, from 1 to 16 m deep.

Ecology: This species lives buried deeply

in sand (10-15 cm deep), under boulders and

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rocks exposing its tentacle crown only when

feeding. Upon slightest disturbance, even shad-

ing, the tentacle crown and the introvert are

swiftly retracted into the body leaving no trace

of the animal.

Remarks: Massinium ocumichoen-

sis sp. nov. is morphologically related to M.

maculosum Samyn & Thandar, 2003 in having

pseudobuttons in the body wall, and introvert

with tables and rosettes, however mid-dorsal

pseudobuttons are slightly bigger in M. ocu-

michoensis sp. nov. (40-60 μm), but smaller

(14-27 μm), thicker, and mainly not perforated

in M. maculosum (Samyn & Thandar, 2003;

Fig. 2B, 2C). Moreover, M. maculosum doesn’t

Fig. 2. Massinium ocumichoensis sp. nov., holotype ICML-UNAM 10078. A. Pseudobuttons from body wall. B. Tables from

body wall. C. Pseudobuttons from introvert. D. Tables from introvert. E. Rosettes from introvert. F. Endplate of tube feet.

G. Rods from tube feet. H. Simple and granuliform rods from tentacles. I. Rosettes from tentacles.

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have tables in the body wall as M. ocumichoen-

sis sp. nov., it only has tables in the introvert

tube feet, ventral tube feet and anal papillae

which possess a high spire (50-75 μm) in com-

parison with those in M. ocumichoensis sp. nov.

which are very short (10 μm) or with an almost

absent spire. When alive M. ocumichoensis

sp. nov. has longer outer tentacles (35-40 mm)

than those in M. maculosum (30 mm) (Samyn

& Thandar, 2003).

M. ocumichoensis sp. nov. is distinguished

from other species in the genus by the combi-

nation of morphological characters shown in

the taxonomic key.

Key to the species of Massinium (modified from O’Loughlin et al., 2014)

1. Ossicles present in the mid-body wall .............................................................. 2

- Mid-body wall lacking ossicles ................................................................. 10

2. Mid-body wall with table ossicles of some form present ............................................... 3

- Mid-body wall lacking any form of table ossicles ................................................... 7

3. Mid-body wall ossicles tables only ................................................................ 4

- Mid-body wall ossicles tables and additional ossicle forms ............................................ 5

4. Peri-oral table spires well developed, typically with long, splayed, pointed apical spines ..... M. bonapartum (NW

Australia)

- Peri-oral table spires frequently absent or reduced, few short apical spines .......... M. keesingi (NW Australia)

5. Mid-body with developed table ossicles, pseudobuttons and rounded plates ........... M. dissimilis (Madagascar)

- Mid-body with tables or reduced table ossicles, pseudobuttons and rosettes .............................. 6

6. Tentacles with rosettes only .................................................... M. magnum (Indonesia)

- Tentacles with granuliform rods and rosettes ................. M. ocumichoensis sp. nov. (NE Pacific, Mexico)

7. Mid-body wall with rosettes present ............................................................... 8

- Mid-body wall lacking rosettes .................................................................. 9

8. Introvert table discs irregular with predominantly four central perforations and single ring of smaller outer perfora-

tions; tentacles with rods and rosettes …………….……… ...................... M. maculosum (South Africa)

- Introvert table discs irregular with predominantly four central perforations and up to three rings of smaller outer

perforations; tentacles with elongate rod-rosettes .............................. M. albicans (New Caledonia)

9. Mid-body ossicles predominantly short, thick, irregular, rarely perforate, granuliform rods; tentacles with rosette ossi-

cles only ............................................................. M. granulosum (NE Australia)

- Mid-body ossicles predominantly U-shaped, distally perforate rods; tentacles

with rod ossicles only ............................................... M. arthroprocessum (South Africa)

10. Large and small tube feet uniformly distributed; 4 polian vesicles; peri-anal body

wall with table ossicles ........................................... M. melanieae (Great Australian Bight)

- Tube feet not uniformly distributed; fewer than 4 polian vesicles; peri-anal body wall lacking table ossicles ... 11

11. Tube feet scattered dorsally, more prominent ventrally; peri-oral table discs with up to 20 perforations; tentacles with

rods and rare rosettes ............................................... M. vimsi (Bass Strait, SE Australia)

- Tube feet more concentrated along longitudinal muscles; peri-oral table discs with up to 40 perforations; tentacles

with rare fine rods, lacking rosettes .................................. M. watsonae (SE Tasmania, Australia)

Ethical statement: authors declare that

they all agree with this publication and made

significant contributions; that there is no con-

flict of interest of any kind; and that we fol-

lowed all pertinent ethical and legal procedures

and requirements. All financial sources are

fully and clearly stated in the acknowledge-

ments section. A signed document has been

filed in the journal archives.

ACKNOWLEDGMENTS

To Berenit Mendoza Garfias (Laborato-

rio de Microscopia Electrónica, Instituto de

Biología [IB], UNAM) for her technical sup-

port with the SEM work, and Susana Guzmán

Gómez (LANABIO-IB, UNAM) for her

photography technical assistance. To Scott

Whitaker (Manager SEM, National Museum

of National History, Smithsonian Institution,

Washington, DC, USA) for his technical assis-

tance when taking the SEM photographs pre-

sented in this work. Thanks to Ma. Esther

Diupotex Chong (ICML, UNAM) for her tech-

nical support including type material in the

Colección Nacional de Equinodermos (ICML,

UNAM). The authors thank Magali Honey,

Quetzalli Hernández, Julio Arriaga, Penélope

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Ayala, Francisco Borras and Tania Enriquez for

helping in collecting the specimens. We would

like to thank M. G. Lovegrove for his valuable

comments on the manuscript’s English and

scientific content. CACV (scholarship holder

666781) thanks the Consejo Nacional de Cien-

cia y Tecnología (CONACyT) for his doctorate

grant 722925.

RESUMEN

Expansión del género Massinium

(Holothuroidea: Thyonidae) al continente

americano y descripción de una nueva especie

Introducción: El género Massinium incluye 11 espe-

cies, la mayoría del Océano Indo-Pacífico, y no se había

reportado previamente en el continente americano. Obje-

tivo: Presentar el nuevo registro del género Massinium

y describir una nueva especie de este. Métodos: La

recolección de material se realizó mediante buceo a una

profundidad máxima de 9 m. Resultados: Massinium ocu-

michoensis sp. nov. se describe a partir de siete ejemplares

que extiende el rango de distribución del género al Conti-

nente Americano (Guerrero, Michoacán y Jalisco, México).

La nueva especie vive en sustratos arenosos-rocosos, de

2 a 16 m de profundidad. Se distingue de sus especies

congenéricas por una combinación de caracteres morfoló-

gicos: pseudobotones de la zona dorsal media ligeramente

más grandes (40-60 μm) y tablas en la pared del cuerpo.

Se proporciona una clave taxonómica para distinguir las

especies de Massinium. Conclusiones: El rango geográfico

del género Massinium se extiende al Pacífico mexicano con

M. ocumichoensis sp. nov.

Palabras clave: Echinodermata; Dendrochirotida; biodi-

versidad; taxonomía; nuevo registro.

REFERENCES

Cherbonnier, G. (1988). Echinodermes: Holothurides.

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php?p=taxdetails&id=390820 on 2020-07-06