NEW INFORMATION ON CRETACEOUS CRABS 
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16 
Fig. 13. Paranecrocarcinus kennedyi sp.nov. Makatini Formation, Barremian, Zululand, South Africa. Reconstruction, based on the holotype, Fig. 7. x ca. 
Bi 
Fig. 14 Rathbunopon ? atherfieldense sp.noy. Lower Greensand, Crackers Bed, Lower Aptian, Atherfield, Isle of Wight. Reconstruction, omitting the 
granulation, based on the holotype, Fig. 9, and paratype. The orbito-frontal margins are diagrammatic, since details of fissures and teeth are not 
preserved. x ca. 8. 
Fig. 15 Paranecrocarcinus biscissus Wright & Collins. Cenomanian Limestone, Whitecliff, Seaton, Devon. Diagrammatic reconstruction, based on 
specimen in Fig. 10. x ca. 4. 
Fig. 16 Withersella crepitans Wright & Collins. Lower Greensand, Crackers Bed, Lower Aptian, Atherfield, Isle of Wight. Diagram of left frontal margin, 
based on specimen in Fig. 12. x ca. 5. 
matrix and visible only from underneath. The cephalothorax is 
roughly pentagonal in outline with slightly convex anterolateral, 
straight posterolateral and slightly concave posterior margins. It is 
weakly arched in transverse and longitudinal sections, with appar- 
ently deeply undercut sides. The front is produced into a broad 
sulcate rostrum, incompletely preserved but showing upwardly 
directed rostral spines. The orbital margins are not well-preserved 
but the orbits appear to have been moderately wide with a fissured 
upper rim and an outer orbital spine; the orbito-frontal width was 
about half that of the carapace. 
The anterolateral margin ends in a spine at the lateral angle, and 
there is one between this and the outer orbital spine. The long 
posterolateral margins are almost straight and converge towards the 
slightly concave posterior margin. 
The cervical sulcus is bent strongly round the rear of the mesogas- 
tric lobe and then takes a sinuous oblique course to the margins. 
Distinct epibranchial sulci branch obliquely to the rear and define 
small triangular epibranchial lobes. The branchiocardiac sulci are 
weaker than the cervical and are more or less parallel to it in their 
outer part; they run back between the small triangular cardiac lobe 
and a small parallel ridge on either side. 
DISCUSSION. The Hauterivian P. hexagonalis has two large tuber- 
cles on the mesogastric lobe but no others forward of the cervical 
sulcus and has a pair of post-rostral slits. The Cenomanian P. 
mozambiquensis Forster, 1970, has a single large tubercle on each 
protagastric lobe. P. libanoticus Forster, 1968, from the Cenomanian 
of Lebanon has a single small tubercle on the mesogastric lobe, two 
large ones on each protogastric and two smaller ones on each 
anterior branchial lobe; it also has two post-rostral slits. The Turonian 
Povalis Stenzel from Texas has an aligned row of large tubercles 
across the hepatic and protogastric lobes as in P. kennedyi, but the 
cephalothorax is much broader than long and has a less pentagonal 
outline, as does the Upper Albian P. graysonensis Rathbun, 1935 
with weaker tuberculation. P digitatus Wright & Collins, 1972, 
from the English Cenomanian has a pair of post-rostral slits (Collins 
et al., 1995: 198), and is characterised by its elongated radiating 
ridges on the protogastric lobes. P. foesteri Wright & Collins, 1972, 
differs in having strongly granulated posterolateral margins and 
posterior edges of the branchiocardiac furrows. However, none of 
these species is known by more than a very few specimens and the 
extent of intraspecific variation is unknown. 
SOME NEW ENGLISH CRETACEOUS CRABS 
Fig. 8 
A poorly preserved Galathea has been found in Lower Aptian 
Crackers material from Atherfield, supplied by Prof. W.J. Kennedy. 
It is inadequate for proper description, but it is worth recording 
since, with a specimen from the Aptian of Spain (Via Boada, oral 
communication), it is probably the oldest known species of the 
genus. 
Galathea sp. nov.? 
Rathbunopon? atherfieldense sp. nov. Figs 9, 14 
TYPES. The holotype is BMNH IC 11 and paratype IC 12, both 
from Lower Greensand, Crackers Bed, Lower Aptian, D. callidiscus 
Zone, Atherfield Point, Isle of Wight. 
DIAGNOSIS. A presumed primitive Rathbunopon, longer than wide, 
with the paired bosses at the rear of the mesogastric lobe small and 
close together; the urogastric lobe feebly developed, divided by a 
shallow longitudinal groove. 
DESCRIPTION. Small, 7 mm long, about 25% longer than wide, 
narrowed in front and with slightly convex margins; strongly arched 
in transverse section, less so in longitudinal; front turned down and 
deeply furrowed; orbitofrontal margins oblique at about 45°. The 
furrows delimiting the mesogastric lobe are shallow in front but 
deepen as they approach the cervical furrow, which is wide and deep 
laterally. The branchiocardiac furrows are shallower than the cervi- 
cal. There is a strong circular epigastric boss on either side of the 
medial furrow, a feeble longitudinal oval one on the anterior process 
