TAXONOMIC REVISION OF FORAMINIFERA IN MILLETT COLLECTION 



113 



1948a Ammobaculites salsus Cushman & Bronnimann: 16; 



pi. 3, figs 7a, b, 8,9 (holotype figs 7a, b). 

 19526 Ammoscalaria fluvialis Parker: 444; pi. 1, fig. 24 



(holotype) only (non fig. 25). 



1953 Ammobaculites salsus (et vars.) Parker et al. : 5; pi. 1, 

 figs 18-25 only (non fig. 17). 



1954 Ammobaculites exilis Cushman & Bronnimann; 

 Phleger: pi. 1, fig. 6 (non Cushman & Bronnimann, 

 19486). 



1954 Ammobaculites salsus Cushman & Bronnimann; 



Phleger: pi. 1, fig. 7 only (non fig. 8). 

 1954 Ammoscalaria fluvialis Parker; Phleger: pi. 1, fig. 11. 



1957 Ammobaculites salsus Cushman & Bronnimann; 

 Todd & Bronnimann; 24, pi. 3, fig. 8 



1958 Ammobaculites salsus Cushman & Bronnimann; 

 Arnal: 37; pi. 98, figs 4-7. 



1968 Ammotium salsum (Cushman & Bronnimann); 



Lutze: 25; pl.l, figs 5,6. 

 1978 Ammotium salsum (Cushman & Bronnimann); Poag: 



405; pi. 5, figs 1-39. 

 1980 Ammotium salsum (Cushman & Bronnimann); Scott 



&Medioli: pi. 1 , figs 11-13. 

 1983 Ammotium morenoi (Acosta); Haman: 72; pi. 5, figs 



6-9. 



morphological variability. She tried to distinguish six differ- 

 ent morphological types on the basis of outline, chamber 

 form, and dimensions of the test and chambers. A study of 

 Brodniewicz's paper, however, suggests to us that it is 

 virtually impossible to separate her different morphotypes. 



Dimensions of figured specimens (MALAY SPECIMEN, 

 BMNHno. 1991.11.1.1122). Height of test— 170 urn; width 

 (length) — 105 urn; thickness — 35 urn. 



(BRAZILIAN SPECIMEN). Height of test — 370 um; 

 maximum width — 190 um; final chamber — 225 um high; 

 maximum diameter of oblong aperture — 50 um. 



Environment. Found only in Station 9 (Area 1) in associa- 

 tion with Ammotium pseudocassis , A. directum, Acupeina 

 triperforata, Ammoastuta salsa and Arenoparella mexicana, 

 all typical brackish water species. A. morenoi is normally 

 abundant in tropical and subtropical mangrove sediments but 

 has also been recorded, albeit rarely, in brackish sediments of 

 temperate climes (Parker, 19526; Lutze, 1968). We have 

 never encountered this species in the British Isles or in the 

 Mediterranean. 



Observations on certain synonyms and non-synonyms 

 (near isomorphs) of ammotium morenoi acosta. 



Remarks. The specimen illustrated by us in Figs 32-34 was 

 not figured or described by Millett but comes from a slide in 

 the Millett Collection labelled Haplophragmium cassis Parker 

 (BMNH no. 1955.11.1.1118-1133) and was undoubtedly part 

 of his concept of that species. It is a typical representative of 

 Ammotium morenoi. The small test is axially compressed and 

 consists of a short, completely coiled planispiral initial stage, 

 followed by an uncoiled portion of about 5 low, elongate, 

 laterally compressed chambers which on the interior side 

 reach back toward the initial planispire. The single aperture is 

 a narrow elongate slit with rounded extremities, situated at 

 the apex of the final chamber, in a marginal or outer position. 



Under the name of H. cassis, Millett (1899, pi. 5, figs 4a, b, 

 5a, b) did illustrate two specimens, which belong to different 

 species of Ammotium. The latter (reproduced here as Fig. 

 1.5a,b) is the upper part of an Ammotium pseudocassis 

 (Cushman & Bronnimann, 19486)(see p. , below) but was not 

 found in the Millett Collection. The former (Fig. 1.4a,b) is a 

 complete specimen of A. directum (Cushman & Bronnimann, 

 19486) and is refigured in Fig. 31. 



In addition to this specimen, we have also illustrated in Fig. 

 54, for the purpose of comparison, the lateral view of a 

 typical specimen of A. morenoi from the mangrove sediments 

 of Guaratiba, Brazil (see Zaninetti et al. , 1977). It consists of 

 an initial, almost involute planispire, followed by two unise- 

 rial, laterally flattened, low and elongate chambers, which on 

 the inner side extend backwards toward the early spire. 



In common with other brackish foraminifera, A. morenoi is 

 highly variable in its overall morphology, in particular in size 

 and in outline of the test in lateral view. From small, almost 

 triangular forms, as represented by the holotype of morenoi 

 or the holotype of Ammoscalaria fluvialis Parker (19526), we 

 find all possible transitions to the elongate slender specimens 

 of Ammobaculites salsus described by Cushman & Bronni- 

 mann (1948a) from Trinidad, or to the large and elongate 

 individuals recorded by Poag (1978) from Gulf Coast estuar- 

 ies. Brodniewicz (1965: 187-194, text-figs 21-25) has shown 

 that a similar form, identified by her as Ammotium cassis 

 (Parker), from the Baltic, is also characterized by a great 



1. Ammobaculites salsus Cushman & Bronnimann, 

 1948a and A. distinctus Cushman & Bronnimann, 

 19486. 



Haman (1983) was the first author to place Ammobaculites 

 (=Ammotium) salsus into synonymy with Acosta's species. 

 In the introduction to his paper, Acosta (1940: 269) wrote 

 that the agglutinating species were rare in the shallow water 

 assemblages from the Gulf of Santa Maria, Camaguey Prov- 

 ince, Cuba, which were dominated by miliolids and nonion- 

 ids. The Gulf of Santa Maria is bordered by extensive 

 mangrove swamps. It is therefore assumed that the tests of 

 the brackish agglutinated species, such as A. morenoi, had 

 been transported by wave action into the marine environment 

 of the open Gulf and were not in situ at the locality where 

 Acosta collected them. Acosta (1940: 275) claimed to have 

 deposited the types of his species in the Cushman Collection, 

 which were later transferred from Sharon, Massachusetts to 

 the U.S. National Museum of Natural History, Washington, 

 D.C. A search by P.B. for the type specimen of A. morenoi 

 proved unsuccessful and it seems that Acosta never did 

 deposit his types in the Cushman Collection. Acosta's draw- 

 ings (op.cit. pi. 49, figs 3,8, non fig. 1) leave no doubt, 

 however, that Ammotium morenoi and A. salsum, originally 

 described from Trinidad mangrove swamps, are one and the 

 same. 



When comparing the two 'species', the apertural view of 

 the holotype of Ammotium morenoi (Acosta, 1940: pi. 49, 

 fig. 8) is of interest. It shows a slit-like opening at the apex of 

 the final chamber, in a marginal or outer position; the same 

 type of aperture occurs in A. salsum. In both holotypes the 

 peripheral outline of the initial planispire, as seen laterally, is 

 perfectly rounded and not angular as in Ammotium distinc- 

 tum (Cushman & Bronnimann (19486: 40, pi. 7, fig. 14), 

 which has also been described from the brackish mangrove 

 sediments of Trinidad. This latter form was originally intro- 

 duced as a variety of Ammobaculites salsus. As there are no 

 intermediates between distinction and salsum, the former is 

 here elevated to specific rank. Authors, however, normally 



