European Journal of Taxonomy 38: 1-5

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2013 • Claude Massin

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Research article

um:lsid:zoobank.org:pub:A5B10105-A73F-4ABl-BF59-2Q95D95638F3

Redescription of Psolus tessellatus Koehler, 1896 (Echinodermata,

Holothuroidea) with neotype designation

Claude MASSIN

Royal Belgian Institute of Natural Seienees, Department of Invertebrate Biology,

29 rue Vautier, 1000 Brussels (Belgium), E-mail: [email protected]

um:lsid:zoobank.org:author:896580A2-73E2-4562-AFCD-6AA69E5125B4

Abstract. In the byeateh of a seientifie eampaign in the Bay of Biseay (VITAE 2002) a third speeimen

of Psolus tessellatus Koehler, 1896 was eolleeted very elose to the type loeality. This speeimen is here

fully illustrated and designated as the neotype.

Key words. Psolidae, Bay of Biseay, redeseription, first illustration, neotype.

Massin C. 2013. Redescription of Psolus tessellatus Koehler, 1896 (Echinodermata, Holothuroidea) with neotype

designation. European Journal of Taxonomy 38: 1-5. http://dx.doi.org/10.5852/eit.2013.38

Introduction

In 1895, the University of Eyon organized a eampaign on board of the “Caudan” in the Bay of Biseay.

During that expedition, material was eolleeted between 110 and 1.710 m depth (Koehler 1896). Four

new holothurian speeies were deseribed and housed in the eolleetions of the University of Eyon:

Holothuria roulei Koehler, 1896 (= Mesothuria roulei (Koehler, 1896)), Parorizapallens Koehler, 1896

(= Stichopus pallens (Koehler, 1896)), Benthogone rosea Koehler, 1896 Psolus tessellatus Koehler,

1896. In 1985, Jangoux revisited the types in the eolleetions of Eyon and only found the type material of

Holothuria roulei and Benthogone rosea. The type material of Paroriza pallens and Psolus tessellatus

was missing and must be eonsidered as lost. Moreover, P. tessellatus was not illustrated by Koehler

(1896).

A seeond eateh of P. tessellatus was mentioned between the Azores and Madeira at 1.100 m depth by

Fiege & Janssen (1998), who first illustrated the speeies.

In 2002, IFREMER Nantes organized a eampaign (VITAE) in the Bay of Biseay for the evaluation of

fish populations. In the byeateh of trawled material one speeimen of Psolus tessellatus was eolleeted. It

is the objeet of the present note.

Material and methods

The speeimen of Psolus tessellatus was eolleeted at Station 14 of the VITAE eampaign (47°36’ N - 8°25’

W, 1399-1442 m, eolleeting date 23 Aug. 2002). It was fixed on a small stone (40 x 44 x 50 mm) and

housed in the eolleetion of the RBINS under the eatalogue number IG31016-HOE 1304.

European Journal of Taxonomy 38: 1-5 (2013)

Abbreviations

BIOGAS

IFREMER

RBINS

VITAL

BlOlogie golf GAScogne

Institut Fran 9 ais de Recherche pour FExploitation de la Mer.

Royal Belgian Institute of Natural Sciences

Victor rove TALus continental

Results

Phylum Echinodermata Brugiere, 1791

Order Denrochirotida Grube, 1840

Family Psolidae Forbes, 1841

Genus Psolus Oken, 1815

Psolus tessellatus¥^OQ\i\Qx, 1896

Figs lA-D, 2A-G

Psolus lessellatus¥^OQ\\[QX, 1896: 119.

Psolus tessellatus - MoxiQXYSQXY 1927: 414. —Fiege & Janssen 1998: 341, figs 2-3.

Psolus tesselatus - Costelloe et al. 2001: 348.

Fig. 1. Psolus tessellatus Koehler, 1896. A. Dorsal view. B. Buccal cone. C. Anal cone. D. Ventral view.

MAS SIN C., P solus tessellatus, redescription, neotype

Redescription

Small oval specimen, 17.4 mm long, 10.6 mm broad and 2.4 mm thick (Fig. lA). Dorsal body wall

covered by large scales (from 850 x 550 to 1350 x 1100 pm) (Figs lA-C, 2A). The scale consists of

one layer at the edge but rapidly becomes multilayered when going to the centre (Fig. 2B). No tube

'Xs

A ^ 'W ' ■ 'O -

, .

■ “

o ■ ;*:

six^o

. 500 |jm

B-G

Fig. 2. Psolus tessellatus Koehler, 1896. A. Dorsal scale. B. Detail of dorsal scale. C. Plates of

ventral sole. D. Rods of large tube feet. E. End plate of large tube feet. F. End plate of small tube feet.

G. Perforated plates at the base of the large tube feet.

European Journal of Taxonomy 38: 1-5 (2013)

feet dorsally. Ten seales between mouth and anus. Anus surrounded by irregular small plates (Fig. 1C).

Mouth surrounded by 10 seales: five large triangular seales alternating with 5 small, elongated seales

(Fig. lA, B). Tentaeles fully retraeted, not observed.

Ventral sole very thin, translueent, ealeareous ring and digestive traet visible by transpareney (Fig. ID).

Ossieles as perforated plates, 100-160 pm long with 1-8 holes (Fig. 2C). Ventral sole with 2 rows of tube

feet at the edge (Fig. ID). Inner row of tube feet large, with perforated rods, 125-280 pm long (Fig. 2D)

and large end plate in one pieee (more or less 300 pm aeross) (Fig. 2F). External row with very small

tube feet with small end plates made of one pieee (more or less 100 pm aeross) (Fig. 2E). At the base of

the large tube feet, perforated plates, 100-170 pm long, similar to those of the ventral sole, sometimes

knobbed (Fig. 2G). No mid ventral tube feet exeept 1-2 at the rear (Fig. ID).

Discussion

The speeimen at hand belongs without any doubt to the genus Psolus: thiek dorsal surfaee eovered by

seales, thin ventral sole, tube feet restrieted to the ventral sole. Only 7 Psolus speeies are known from

the Northeast Atlantie Oeean, viz P. fabricii (Duben & Koren, 1846), P. hypsinosus Heding, 1942, P.

nummularis K. Perrier, 1899, P. phantapus 1767), E pourtalesiThQQl, 1886, P. squamatus

(Muller, 1776), andE tessellatusY^oohXQX, 1896.

E tessellatus is readily separated from the other mentioned speeies by the valves surrounding the mouth:

5 large triangular ones alternating with 5 narrow ones. It is also the only Psolus speeies mentioned

here with 10 seales present between mouth and anus. For E hypsinosus and E fabricii (see Heding

1942) there are only 5-7 seales between mouth and anus, whereas for E pourtalesi, P squamatus and E

nummularis (see Theel 1886; Deiehmann 1930; Madsen & Hansen 1994; Perrier 1902) there are over

15. E tessellatus is also the only Psolus speeies present in the Bay of Biseay.

The speeies seems to have a very restrieted distribution and bathymetry in the Bay of Biseay: 45°47’ N

- 6°15’ W and 1.700 m for the holotype, and 47°36’ N - 8°25’W and 1.400 m for the present speeimen.

In deeper water (1900-4800 m) holothurians are abundant (34 speeies, Sibuet 1977) but E tessellatus

was not mentioned in spite of intensive sampling by IFREMER Brest (BIOGAS, Sibuet 1977; Sibuet &

Segonzae 1985). IFREMER Nantes has intensively sampled at depths of 0-500 m with a few samples

at 1000 m (J. Martin, personal eommunieation; Sea Cruises Inventory 2012), but no E tessellatus were

eolleeted.

The rarity of E tessellatus eould be an artefaet linked to the low intensity of sampling between 1.000 and

I. 700 m, a zone obviously favourable to the speeies (Fiege & Janssen 1998).

Sinee the holotype is lost and Koehler (1896) did not give any illustrations of the holotype (general

aspeet and ossieles) and sinee the speeimen studied here was eolleeted very elose to the type loeality, it

is here designated as the neotype of E tessellatus (see International Code of Zoologieal Nomenelature,

artieles 75, 75.3.4, 75.3.6.).

Acknowledgements

It is a pleasure to thank Dr. Y. Samyn (RBINS) for co mm ents on the first draft of this manuseript, Mm e

J. Martin (IFREMER Nantes) for allowing me to study material from the VITAE Campaign and Mr. A.

Van Haelen for the photographs on Plate 1.

MAS SIN C., P solus tessellatus, redescription, neotype

References

Costelloe M., Emblow C. & White R. 2001. European Register of Marine Species: a check-list of the

marine species in Europe and a bibliography of guides to their identification. Patrimoines Naturels 50,

Museum National d’Histoire Naturelle, Paris.

Deiehmann E. 1930. The holothurians of the western part of the Atlantie Oeean. Bulletin of the Museum

of Comparative Zoology at Harvard College 71 (3): 41-226.

Fiege D. & Janssen R. 1998. Ein Fall von Parasitismus bei Psolus tessellatus einer ungewohnliehen

Holothurie. Natur und Museum 128 (10): 341-344

Heding S.G. 1942. Holothuroidea II. The Danish Ingolf-Expedition IV (13): 1-39.

JangouxM. 1985. Catalogue eommente des types d’Eehinodermes aetuels eonserves dans les eolleetions

lyonnaises. Nouvelles Archives du Museum d’Histoire naturelle de Lyon 23: 3-11.

Koehler R. 1896. Eehinodermes. Resultats Scientifiques de la campagne du «Caudan» dans le golfe de

Gascogne 1: 33-127.

Madsen F.J. & Hansen B. 1994. Echinodermata Holothuroidea. Marine Invertebrates of Seandinavia 9,

Seandinavian University Press, Norway.

Mortensen T.H. 1927. Handbook of the Echinoderms of the British Isles. Oxford University Press,

Eondon.

Perrier R. 1902. Holothuries. In\ Perrier R. (ed.) Expeditions Scientifiques du «Travailleur» et du

«Talisman»: 273-554. Masson, Paris.

Sea Cruises Inventory. 2012. http://www.ifremer.fr/sismer/UK/eatal/eampagne/indexorga2_armat.

htql? eorg=IFREM

Sibuet M. 1977. Repartition et diversite des Eehinodermes (Holothurides-Asterides) en zone profonde

dans le Golfe de Gaseogne. Deep-Sea Research 24: 549-563.

Sibuet M. & Segonzae M. 1985. Abondanee et repartition de Eepifaune megabenthique. In\ Eaubier E. &

Moniot C. (eds) Peuplementsprofonds du Golfe de Gascogne, campagne Biogas: 143-156. IFREMER,

Brest.

Theel H. 1886. Reports on the Results of Dredging in the Gulf of Mexieo (1877-78), in the Caribbean

Sea (1879-80), and along the Eastern Coast of the United States during the Summer of 1880 by the U.

S. Coast Survey Steamer “Blake”. Bulletin of the Museum of Comparative Zoology at Harvard College

13 (1): 1-21.

Manuscript received: 5 December 2012

Manuscript accepted: 28 January 2012

Published on: 7 February 2012

Topic editor: Rudy Jocque

Desk editor: Kristiaan Hoedemakers

Printed versions of all papers are also deposited in the libraries of the institutes that are members of

the EJT eonsortium: Museum National d’Histoire Naturelle, Paris, Franee; National Botanie Garden

of Belgium, Meise, Belgium; Royal Museum for Central Afriea, Tervuren, Belgium; Natural History

Museum, Eondon, United Kingdom; Royal Belgian Institute of Natural Seienees, Brussels, Belgium;

Natural History Museum of Denmark, Copenhagen, Denmark.