A Field Guide to the Cretaceous and Cenozoic Fossil Decapod Crustacean Localities of Jamaica
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Caribbean Journal of Science, Vol. 46, No. 1, 39-53, 2010 Copyright 2010 College of Arts and Sciences University of Puerto Rico, Mayagüez A field guide to the Cretaceous and Cenozoic fossil decapod crustacean localities of Jamaica Stephen K. Donovan * Department of Geology, Nederlands Centrum voor Biodiversiteit – Naturalis, Postbus 9517, NL-2300 RA Leiden, The Netherlands *Corresponding author; [email protected] A BSTRACT. — Jamaica has a rich invertebrate fossil record. The principal localities for fossil decapod crusta- ceans are Upper Cretaceous (two sites), Paleocene (one site), Eocene (four sites), Miocene (one site), Pliocene (one site) and Pleistocene (six sites); there are no Oligocene localities. Few taxa and specimens are known from the Upper Cretaceous and Paleogene, but this is interpreted, in part, as collection failure. Neogene localities have produced much more diverse faunas, but the only site to yield moderately common and diverse carapace remains is Lower Miocene. K EYWORDS. — Jamaica , Decapoda , fossil crabs , Cretaceous , Cenozoic , stratigraphy. Introduction papers, GPS readings, and inclusion of (or Of all the Antillean islands, none has a reference to) detailed locality maps. fossil record that is so celebrated and well The purpose of the present communica- known as that of Jamaica (Wright and tion is to provide a guide to the fossil locali- Robinson, 1993), and no other island has ties in Jamaica that have produced decapod yielded fossil decapod crustaceans from crustaceans. As such, it will be an essen- such a broad stratigraphic range and from tial guide to any collectors without previ- so many localities. Two periods of activ- ous experience of the Jamaican rock record ity can be recognized during which fossil and will provide an accessible survey of decapod crustaceans have been collected what is known currently. Locality maps are from Jamaica. In the 1920s, two collectors, provided, where possible, for the Upper Drs D. Woolacott and, principally, Charles Cretaceous and Eocene localities of Woolacott T. Trechmann collected specimens from the and Trechmann as documented by Withers Upper Cretaceous and Paleogene which (1922, 1924, 1927), as well as for sites discov- were described by Thomas H. Withers of ered more recently; data available for the the British Museum (Natural History). All latter is invariably more precise. Only sites were published with locality and strati- that have yielded indeterminate remains or graphic information, but without locality taxa without adequate site data are not con- maps. Since the late 1980s, fieldwork has sidered herein (for example, Morris, 1993, largely concentrated on the Neogene of the p. 120, 123). See Donovan et al. (2003) and island. The first new paper on Jamaican fos- Collins et al. (2009c) for stratigraphic sur- sil decapods, published over 65 years after veys of the Jamaican fossil decapods. the last paper on the subject by Withers, Grid references used herein refer to was by Morris (1993), who described spec- the 1:50,000 topographic (metric edition) imens supplied by the present author, but maps, which can be obtained from Edward subsequent descriptions have been made Stanford Ltd., 12/14 Long Acres, London, by four principal collectors and their associ- WC2E 9LP, England. 1:50,000 geological ates, namely Joe Collins, Roger Portell, the maps (provisional series) may be obtained late Hal Dixon and Donovan. These were from the Geological Survey Depart ment, published with grid references and, in later Hope Gardens, Kingston 6, Jamaica. Of the 39 40 S. K. DONOVAN many guides to Jamaican geology available, confusion. Figure 1 illustrates the distribu- Robinson (1994) provides a reasonably up- tion of parishes within Jamaica, where par- to-date account, which can be supplemented ishes are analogous to American states or by the specialist references referred to herein. British counties. Figure 2 shows the distribu- For a map of the Cre taceous inliers, see tion of decapod-bearing localities within the Donovan and Bowen (1989, text- fig. 1 ). island and can easily be used in conjunction Two general maps of Jamaica are pro- with Figure 1 . The stratigraphic position of vided, separating geographic data to avoid the each locality in Figure 2 is indicated by Fig. 1. Modern parish map of Jamaica (redrawn after Higman, 1988, fig. 1.2). These parishes are further grouped together as three counties, Middlesex (including the parishes of Manchester, St Ann, Clarendon, St Catherine and St Mary) in the center of the island, Cornwall to the west and Surrey in the east. Coastline stippled. Fig. 2. Locality map. Outline map of Jamaica with parish boundaries (dashed lines; compare with Fig. 1 ) and decapod crustacean localities (). Locality numbers explained in text. Scale and orientation identical to Figure 1 . JAMAICAN FOSSIL DECAPOD CRUSTACEAN LOCALITIES 41 the prefix (see below), for example, Eo1 is Eocene Locality 1. Materials and Methods The data used in the present study is, at worst, still reasonably good. The four locali- ties referred to by Withers - two Cretaceous (K1 and K2) and two Eocene (Eo1 and Eo2) - were published with sufficient information to define the general area from which speci- mens were collected ( Fig. 2 ). All are inland exposures, which in Jamaica suggests that road cuts, railroad cuttings, hillsides and river exposures are the most likely sites for collecting. However, all of the speci- mens described by Withers were provided by other collectors; locality maps and mea- sured sections were not published with the descriptions, presumably because they weren’t available. More recent collections (all other localities discussed herein) were made with reference to modern topographic maps and, in some instances, measured sec- tions; global positioning systems (GPS) have been used to confirm some locality data. Results Cretaceous – Locality K1 Locality.— “From grey calcareous shale in the bed of the Río Minho a little to the west of Trout Hall, Chapelton, [parish of Fig. 3. Outline maps of principal localities for Upper Clarendon, central] Jamaica. The shale is Cretaceous decapod crustaceans of Jamaica. (A) Area several feet thick, and one band of it, about of Locality K1. About 1 km west of the Trout Hall road junction, the main road to Frankfield (B4) permits easy 3 feet [c. 0.9 m] in thickness, is crowded access to the bed of the Río Minho (Mitchell, 2002). with Rudistae [=the extinct rudist bivalves], (B) Area of Locality K2. Trechmann (1922, fig. 3 ) showed forming a Rudist-bank. The crab remains the section on the railway to be Yellow Lime stone Group were obtained from this bank” (Woolacott (Eocene) near Cambridge and Cretaceous towards in Withers, 1922, p. 535). This part of the Catadupa. Key: solid lines = principal roads; trellised Río Minho ( Figs 2 , 3A ) in the Central Inlier lines = disused railways; stippled lines = main rivers. is well known for its rich fossil remains, The north arrow and scale bar apply to both maps. including rudists, scleractinian corals, act- aeonellid gastropods and oysters (Woolacott includes both carapaces and chelae. Withers in Withers, 1922, p. 535-536). Presumably, (1924, p. 91) and Morris (1993, p. 120) also Woolacott’s site was close to stop 3 of recorded this species from the same for- Mitchell (2002). mation at Logie Green, 8 km west of Trout Horizon.— Guinea Corn Formation, Central Hall, parish of Clarendon, and in the river Inlier. Upper Cretaceous, upper Campanian valley below Catadupa, parish of St James (?) to lower Maastrichtian (Robinson, 1994, ( Fig. 3B , west of the railway), presumably fig. 6.4; Mitchell 2003, p. 613-614). close to K2. The imprecision of this locality Decapod fauna.— Type locality of Carci- data would make relocation of these hori- neretes woolacotti Withers, 1922; type mater ial zons difficult, at best. 42 S. K. DONOVAN Cretaceous – Locality K2 Locality.— “. shales with Roudaireia , Trigonia , etc., about 40 feet [c. 12 m] below Rudist Limestone; railway line between Cambridge and Catadupa, Great River Valley, [parish of St James,] West Central Jamaica” (Withers, 1927, p. 178) ( Figs 2 , 3B ). Trechmann (1922, fig. 3 ) published a section along this railroad (now disused); see also Trechmann (1927, p. 28-29). Horizon.— Veniella Shale (Morris, 1993, p. 120), Marchmont Inlier. Upper Cretaceous, Maastrichtian (Chubb in Zans et al., 1963, p. 13). Decapod fauna.— Type locality of Creta- coranina trechmanni (Withers, 1927); the unique holotype is a carapace retaining some limb fragments. Paleocene – Locality Pa1 Locality.— Fellowship, parish of Portland, northeast Jamaica (approximate NGR 071 651; new 1:50,000 (metric edition) topo- graphic sheet 14, ‘Port Antonio’) ( Figs 2 , 4 ). Steep cliffs immediately upstream of the Fig. 4. Outline map of the Fellowship area, south of bridge. Body fossils are concentrated in thin Port Antonio, parish of Portland, showing the position of Locality Pa1 (*) on the banks of the Río Grande shell lags on the soles of turbidite sand- (slightly modified after Donovan et al., 1990, fig. 3 ). stones and are best seen in fallen slabs. See Look for macrofossils on the soles of sandstone beds in Donovan et al. (1990, pp. 56-57). the float, where they are preserved as shell lags. This Horizon.— Richmond Formation, ‘Moore fauna remains undescribed apart from decapods Town shales’ of Jiang and Robinson (1987, (Collins and Donovan, 2007) and echinoids (Donovan p. 42-44). Lower Paleocene, Danian (NP1). and Veltkamp, 1992). Decapod fauna.— Trechmannius circularis Collins and Donovan, 2007. Only known Chapelton Formation, Yellow Limestone from the holotype, a carapace. Group. Upper Lower to lower Middle Eocene (Robinson, 1994, fig. 6.5). The giant Eocene – Locality Eo1 cerith referred to by Withers is almost certainly Campanile trevorjacksoni Portell Locality.— “Spring Mount, [parish of and Donovan, 2008. St James,] 6 miles S. E. of Montego Bay, Decapod fauna.— Type locality of ‘ Callian- [western] Jamaica” (Withers, 1924, p. 84) assa ’ trechmanni Withers, 1924, and ‘ Callian- ( Figs 2 , 5A ).