A fairly well-preserved ophiuroid, collected from micaceous sandy argillites of the Messaney Formation (Domerian, late Pliensbachian) as exposed at Rachecourt (Gaume, Belgian Lorraine) is described and tentatively identified as Sinosura wolburgi (Hess, 1960). The rarity of complete ophiuroid fossils in Belgian Jurassic deposits and the poor fossil content of the Messaney Formation (bioelastic beds, crinoid columnals) warrant description of the present specimen

Delsate, D.

Jagt, J.W.M.

Open Marine Archive

BULLETIN DE LTNSTITUT ROYAL DES SCIENCES NATURELLES DE BELGIQUE SCIENCES DE LA TERRE, 66: 203-207, 1996
BULLETIN VAN HET KONINKLIJK BELGISCH INSTITUUT VOOR NATUURWETENSCHAPPEN. AARDW ETENSCHAPPEN, 66: 203-207, 1996
A note on an early Jurassic ophiuroid 
from Rachecourt (Lorraine, Belgium)
by Dominique DELSATE & John W.M. JAGT
Abstract
A fairly well-preserved ophiuroid, collected from m icaceous sandy 
argillites o f the M essancy Formation (Domerian, late Pliensbachian) 
as exposed at Rachecourt (Gaume, Belgian Lorraine) is described and 
tentatively identified as Sinosum wolburgi (Hess, 1960). The rarity o f  
complete ophiuroid fossils in Belgian Jurassic deposits and the poor 
fossil content o f  the M essancy Formation (bioclastic beds, crinoid 
columnals) warrant description o f  the present specimen.
Key-words: Ophiuroid. Domerian. Belgium.
closely resem bling the R achecourt find, w ith a pentagonal disc 
o f 11 mm diam eter, and a greatest preserved arm length o f 25 
mm, from the Grès de Luxem bourg (H ettangian) o f Côte 
d ’Eich, in the city o f Luxemburg. The Natural History M useum 
o f Luxem burg keeps a num ber o f recently collected w ell-pre­
served ophiuroids from the ? Dom erian o f D ahlem  (undescribed 
specimens). K u t s c h e r  &  H a r y  (1991) recorded the genus 
S inosum  from the early Sinem urian o f southeastern Luxem ­
burg.
Résumé
Un spécimen assez bien conservé d ’ophiuroïde, découvert dans les 
argilites feuilletées sablo-micacées de la Formation de M essancy (Do- 
mérien, Pliensbachien supérieur), à Rachecourt (Gaume, Lorraine 
belge), est décrit et identifié com me Sinosum  wolburgi (Hess, 1960). 
Les ophiures fossiles com plètes sont rares dans le Jurassique belge. A 
part quelques lumachelles et articles de crinoides, de rares ammonites 
et bivalves, la Formation de Messancy est peu fossilifère.
Mots-clefs: Ophiuroïde, Domérien, Belgique.
Geographic and stratigraphie setting
The specim en was collected by V ivian D e v  a u x ,  in the Rue 
Basse, N° 102 at Rachecourt (Aubange) (Fig. 1), from the 
“ M acigno, Schistes et Psam m ites de M essancy, à A m altheus  
m argarita tus" , the Vr c o f  the Belgian G eological Map.
The ophiuroid is preserved as an internal mould in a m icac­
eous, limonitic argillite, typical o f the local low er Domerian 
m argaritatus Zone.
Previous records of ophiuroids from Belgium and 
Luxemburg (Lorraine)
M a u b e u g e  (1955, section 184) reported a 4 cm  long ophiuroid 
arm from an outcrop in the low er “ Argiles à A m althées”  
(Pliensbachian, transition betw een the “ Schistes d ’E the”  and 
the “ Schistes et Psam m ites de M essancy” ), in a rail cutting 
near Latour, associated with colum nals o f  isocrinid crinoids, 
cidarid spines, “ A equipecten”  aequivalvis, and juvenile am ­
m onites o f the genera Liparoceras and Lytoceras . M a u b e u g e  
(1973) illustrated and described as O phiurites sp. a specimen
to Habergy
to Meix-le-Tige
RACHECOURT
Fig. 1 —  Location map showing the locality (arrow). 
Scale: 1/42.000
204 Dominique DELSATE & John W.M. JAGT
Description
Class Ophiuroidea 
?Family O phioleucidae M a tsu m o to , 1915 
Genus: S inosum  H ess , 1964, p. 779
Type species: Acroura brodiei W right, 1866, by original diag­
nosis.
S inosum  wolburgi (H ess , I9 6 0 )?
Plate 1
1960b O phiopinnal wolburgi H e ss , p. 411, figs. 29-33.
1963 O phiopinndl wolburgi H e ss -H e ss , p. 1148, figs. 8- 
10 .
1964 S inosum  wolburgi (H ess)-H ess , p. 779.
1965a Sinosum  wolburgi H ess-H ess , p. 1061, figs. 1-3.
1966 Sinosum  wolburgi H ess-H ess , p. 1036, figs. 17-19,
26.
1975c Sinosum  wolburgi H ess-H ess , p. 44, figs. 17, 18,
pi. 5, fig. 9 ; pi. 6, figs. 1-4, 8 ; pi. 10, figs. 11,12.
1987 S inosum  wolburgi (H ess , 1960) - K u tscher , p. 58, 
pi. 5, figs. 1,2.
The disc IRScNB. N ° M TC 10661 is low and more or less flat, 
near-circular with slightly concave interradial margins, with a 
diam eter o f c. 5-5,5 mm. Above the arm bases (i.e. over the 
radial plates) the disc is slightly swollen, but this may in part be 
taphonom ically induced, as is the depression o f the central area 
o f the disc. The dorsal surface o f the disc is granulate (with the 
granulation extending to the proxim alm ost parts o f the arms), 
but plating is obscured. A ssum ing the radial shields to represent 
the above-m entioned disc swelling, these abutting plates are 
apparently small, com prising slightly more than one third of 
disc diam eter. The ventral surface o f the disc is poorly pre­
served, a rusty cover obscuring details o f plating and mouth 
frame. The interradial area apparently com prises but a single, 
granulate plate whose w ider distal margin corresponds to the 
disc margin, and whose proximal m argin abuts the com para­
tively slender oral shield, which is longer than wide, w idest at 
m idlength, and with a more o r less pointed proxim al margin. 
The outlines o f two slender, bar-like adorai shields can be made 
out, but their proximal m argins are poorly preserved; it appears 
that they do not touch. Such is the state o f preservation that it is 
im possible to describe the mouth slit, apical and oral papillae 
and genital slit.
All o f the arm s are more or less com plete, one o f  them 
com prising at least 30 jo in ts over a length of 18 mm. Arms 
are w idest at the disc margin (c. 1,5 mm), and taper com para­
tively gradually. Partly on account o f poor preservation, but 
also due to the thinness o f the lateral arm plates, dorsal arm 
plates cannot be recognised with certainty, but in the proximal 
portion o f one arm there are seen small, m ore or less rounded- 
triangular to pyriform  plates where the lateral arm plates m eet 
over the arm, but exact boundaries betw een these arm plates 
cannot be determ ined. Lateral arm plates, w hich have been 
angular ventrally, show a distinct striation and m eet over the 
arm dorsally, with 7 to 10 short, appressed, pointed spines, the 
length of which increases gradually ventrally, and the largest o f 
w hich may equal nearly half the arm plate length. Dorsally, the 
distal m argin o f the lateral arm plates curves back towards the
disc. Ventral arm plates apparently have straight or slightly 
concave distal m argins, with large tentacle pores, the size o f 
w hich is m ainly determ ined by the large ventral indentation o f 
the lateral arm plates. The num ber o f tentacle scales cannot be 
determ ined exactly because o f poor preservation, but seem s to 
have been one or two. Tentacle pores extend over the entire arm 
length.
Discussion
A mongst NW European fossil ophiuroids those o f Jurassic age 
are the best known, having been the subject o f detailed studies 
by H e s s  (1960a-c, 1962a,b, 1963, 1964. 1965a,b, 1966, 1970, 
1975a-c, 1985, 1991), E n a y  &  H e s s  (1962. 1970), and a 
num ber o f other authors ( G u i l l a u m e ,  1926 ; K u t s c h e r ,  
1987, 1992; K u t s c h e r  &  H a r y ,  1991; R o m a n  et al., 1993).
A lthough diagnostic features o f the Rachecourt specim en are 
com paratively poorly preserved, the suite o f preserved charac­
ters suggest the specim en to belong either to S inosum  wolburgi 
( H e s s ,  1960) or “ G eocom a" elegans H e l l e r ,  1858, type spe­
cies o f the genus O phiopinna  H e s s ,  1960a, o f early Callovian 
age. These species differ prim arily in their vertebral structure, 
while the latter species has feather-like spines in the middle arm 
portion. N one o f these features is preserved in the Rachecourt 
specimen, but it does have the following characters in comm on 
with the above-m entioned species:
—  large tentacle pores ;
—  striation o f (at least) lateral arm plates ;
—  distal m argin o f lateral arm plates curving back proxim ally ;
—  many spines on lateral arm plates ;
—  ? angular lateral arm plates (ventrally).
A com parison w ith the material recorded by H e s s  (1966, 
p. 1036, figs. 17-19, 26), and especially the proximal arm 
fragm ent w ith parts o f the disc preserved (his fig. 19), from 
the early Late O xfordian o f  Sw itzerland, shows that the char­
acter o f disc granulation, size o f tentacle pores, and num ber o f 
spine attachm ent scars on and striation o f  the lateral arm plates 
correspond fairly well with that o f the Rachecourt specimen.
O f note in this respect is the fact that K u t s c h e r  &  H a r y  
(1991) recorded from the early Liassic bucklandi and sem icos­
tatum  Zones (early Sinem urian) o f southeastern Luxemburg 
am ongst other ophiuroid species, S inosum  brodiei n.ssp.? and 
S. cf. wolburgi, rem arking that, should the latter ossicles really 
prove to belong to S.wolburgi, the stratigraphie range o f  that 
species would be extended from the Sinem urian to the middle 
O xfordian. The present record from  the Pliensbachian o f Ra- 
checourt falls w ithin this range, and the specim en is here 
referred to that species with a query.
Acknowledgements
We are greatly indebted to Manfred Kutscher (Saßnitz, Rügen), for 
sharing with us his view s on the specimen, and for suggesting the 
above tentative identification. Vivian Devaux (Rachecourt) is ac­
knowledged for allowing us to study his find and for donating it to 
the Institut Royal des Sciences Naturelles de Belgique in Brussels. The 
photographs were prepared by Jean-Pierre Laurent (Virton), for which 
we are grateful.
Jurassic ophiuroid from Rachecourt 205
References
E n a y , R. & H ess , H., 1962. Sur la découverte d ’Ophiures 
(Ophiopetra lithographica  n.g. n.sp. ) dans le Jurassique supér­
ieur du H aut-Valrom ey (Jura m éridional). Eclogae geologicae 
Helvetiae, 55 (2): 657-673, 2 pis.
E n a y , R. &  H ess , H „  1970. Nouveaux gisem ents à Stelléroides 
dans le K im m éridgien supérieur (Calcaires en plaquettes) du 
Jura méridional - Ain , France. Eclogae geologicae Helvetiae, 
63 (3): 1093-1107, pis. 1 , 2 .
G u illa u m e , L., 1926. Ophiopeza Portei, Ophiure nouvelle du 
Bathonien supérieur de Ranville (Calvados). Bulletin de la 
Société géologique de France, (4) 26: 117-126, pi. 6.
H ess , H ., 1960a. N eubeschreibung von Geocoma elegans 
(Ophiuroidea) aus dem unteren Callovien von La Voulte-sur- 
Rhône (Ardèche). Eclogae geologicae H elvetiae, 53(1): 335- 
385.
H ess , H . , 1960b. O phiurenreste aus dem  M alm des Schweizer 
Juras und des D epartm ents Haut-Rhin. Eclogae geologicae 
Helvetiae, 53(1): 385-421.
H ess , H., 1960c. Ophioderma escheri H eer aus dem  unteren 
Lias der Scham belen (Kt. Aargau) und verw andte Lias-Ophiu- 
ren aus England und D eutschland. Eclogae geologicae H elve­
tiae, 53(2): 757-793.
H ess , H ., 1962a. M ikropaläontologische U ntersuchungen an 
O phiuren. 1. Einleitung. Eclogae geologicae Helvetiae, (55)2: 
595-608.
H ess , H ., 1962b. M ikropaläontologische Untersuchungen an 
Ophiuren. II. Die O phiuren aus dem  Lias (Pliensbachien-Toar- 
cien) von Seewen (Kt. Solothurn). Eclogae geologicae H elve­
tiae, 55(2): 609-656.
H ess , H ., 1963. M ikropaläontologische Untersuchungen an 
Ophiuren. III. D ie Ophiuren aus dem  Callovien-Ton von Lies- 
berg (Berner Jura). Eclogae geologicae Helvetiae, 56(2): 1 M I­
II  64.
Hess, H., 1964. Die Ophiuren des englischen Jura. Eclogae 
geologicae H elvetiae, 57(2): 755-802, 10 pis.
H ess , H., 1965a. M ikropaläontologische Untersuchungen an 
Ophiuren. IV. Die Ophiuren aus dem  R enggeri-Ton (Unter- 
Oxford) von Chapois (Jura) und Longecom be (Ain). Eclogae 
geologicae Helvetiae, 58(2): 1059-1082.
H ess , H, 1965b. O phiuren-Reste (Echinoderm ata) aus den 
N euburger Bankkalken (M ittel-Tithon) des Fränkischen Jura. 
M itteilungen aus der Bayerischen Staatssam m lung fü r  Paläon­
tologie und historische Geologie, 5: 179-184.
H ess , H., 1966. M ikropaläontologische Untersuchungen an 
Ophiuren. V. D ie O phiuren aus dem  A rgovien (unteres Ober- 
O xford) von G uldenthal (Kt. Solothurn) und von Savigna 
(Dépt. Jura). Eclogae geologicae H elvetiae, 59(2): 1025-1063. 
H ess , H., 1970. Ein neuer Schlangenstern (Aplocom a mutata  
n.sp. ) aus dem H ettangien von Ceilhes (H érault) und Bem er­
kungen über Ophioderma squam osa  aus dem  M uschelkalk. 
Eclogae geologicae H elvetiae, 63(3): 1059-1067.
H ess , H ., 1975a. M ikro p a läo n to lo g isch e  U n tersu ch u n g en  an
Ophiuren. VI. Die Ophiuren aus den Günsberg-Schichten (obe­
res Oxford) von G uldental (Kt. Solothurn). Eclogae geologicae 
H elvetiae, 68(3): 591-601, 1 pi.
H ess , H., 1975b. M ikropaläontologische Untersuchungen an 
Ophiuren. VII. Die Ophiuren aus den H um eralis-Schichten 
(Ober-Oxford ) von Raedersdorf (Ht-Rhin). Eclogae geologi­
cae H elvetiae, 68(3): 603-612, 3 pis.
H ess , H., 1975c. Die fossilen Echinoderm en des Schw eizer 
Juras. Veröffentlichungen des naturhistorischen M useum Basel, 
8: 130 pp. , 48 pis.
H ess , H., 1985. Schlangensterne und Seelilien aus dem unteren 
Lias von Hallau (Kanton Schaffhausen). M itteilungen der 
naturforschenden Gesellschaft Schaffhausen, 33 (1985-1988): 
1-13.
H ess , H., 1991. Neue Schlangensterne aus dem  Toarcium  und 
Aalenium des Schw äbischen Jura (Baden-W ürttem berg). S tu tt­
garter Beiträge zur Naturkunde, (B) G eologie und Paläontolo­
gie, 180: 1-11.
K u tsch er , M., 1987. Die Echinoderm en der Callovien-G e- 
schiebe. D er Geschiebesamm ler, 1987/2-3: 53-104, 13 pis.
K u tsch er , M., 1992. Ophiom usium  geisingense  n.sp. - eine 
neue O phiurenart aus dem  Lias Epsilon (Unteres Toarcium ) 
von Bachhausen / Bayern. A rchaeopteryx, 10: 25-30, 2 pis.
K u tscher , M. & H a ry , A., 1991. Echinoderm en im Unteren 
Lias (bucklandi - und sem icostatum  -Zone) zw ischen Ellange 
und Elvange (SE-Luxem burg). N eues Jahrbuch fü r  Geologie 
und Paläontologie, Abhandlungen, 182 (1): 37-72.
M a u beu g e , P.L., 1955. Terrains du Trias et du Jurassique de 
l’Est du Bassin de Paris. PhD Thesis. 2 v o l . , 1082 pp., privately 
published, Nancy.
M a u beu g e , P.L., 1973. Insecte et Stelleroide du Jurassique 
inférieur luxem bourgeois. H istoire N aturelle du Pays de L u­
xembourg, Géologie, Publications du M usée dH istoire N atu­
relle de Luxem bourg, 3 pp.
R o m a n , J., B reto n , G. & V a d o n , C., 1993. O phiurides et 
astéride (Echinoderm ata) du Tithonien de Canjuers (Var, Fran­
ce). Annales de Paléontologie  (V ert.-Invert.), 79 (1 ): 1-18,2  pis.
D. D elsate  
5, Rue du Quartier,
B-6792 Battincourt, Belgium
J.W .M . J agt  
Dienst KCO, 
N atuurhistorisch M useum  M aastricht, 
P.O. Box 882,
N L-6200 AW M aastricht,
The N etherlands
Typescript subm itted February 15, 1995 
Revised m anuscript received D ecem ber 1, 1995.
206 Dominique DELSATE & John W.M. JAGT
P late  1
S inosum  wolburgi (H ess , 1960) ?, from the lower Domerian o f Rachecourt.
Fig. 1 —  ventral face - face orale (barre-échelle /  scale-bar: 1,2 mm)
Fig. 2 —  dorsal face - face aborale (barre-échelle / scale-bar: 1,7 mm)
Jurassic ophiuroid from Rachecourt 207


A note on an early Jurassic ophiuroid from Rachecourt (Lorraine, Belgium)

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