Fig. 21. 1 - Earliest figure of A. clavata, from Carpenter, Parker & Jones (1862); 2 - specimen from Wright (1891); 3 - lectotype from the Parker Collection, BMNH. ORIGINAL DESIGNATION: Trochammina irregularis (d'Orbigny) var. clavata Jones & Parker, 1860. TYPE REFERENCE: Jones, T.R. & Parker, W.K. 1860. On the Rhizopodal fauna of the Mediterranean compared with that of the Italian and some other Tertiary deposits. Quarterly Journal of the Geological Society of London, 16, 292-307 (no figure given). The earliest figure was given by Carpenter et al. (1862, pl. 11, fig. 6). TYPE SPECIMEN: Deposited in the micropaleontological collections of the British Museum (Natural History). Twelve slides containing syntypes, forming part of the W.K. Parker Collection, were purchased by the British Museum (Natural History), and subsequently catalogued by T.R. Jones in 1892. These slides are registered as follows: We could not identify with certainty the specimen illustrated by Carpenter et al. (1862) in pl. 11, fig. 6. However, numerous co-type specimens are preserved. Our choice of a lectotype is the specimen from the Parker Collection which best corresponds to the original illustration. TYPE LEVEL: Recent. TYPE LOCALITY: Jones & Parker (1860) recorded T. irregularis var. clavata at eight localities in the Mediterranean, at depths of 90 to 1700 fathoms. The specimen illustrated by Carpenter et al. (1862) probably came from a dredge sample collected on 29 Sept. 1859 aboard the HMS Firebrand from a depth of 320 fathoms, at 38° 00'N, 9° 13'E (off Galita Island, Malta) in the Mediterranean. This is the only sample preserved in the Parker Collection which contains well-preserved specimens of A. clavata attached to pteropod shell debris, as depicted by Carpenter et al., (1862). DIAGNOSTIC FEATURES: Test commonly attached to shell fragments, sand grains or other foraminifers, consisting of a large ovoid proloculus followed by a narrower tubular chamber. Wall finely agglutinated, several grains thick, with a smooth surface, and both inner and outer pseudochitinous organic linings. Cement undifferentiated organic matter (Bender, 1995). Primary aperture at the open end of the tube. Some specimens, including the types, have a secondary aperture near the base of the proloculus, opposite the main apertural tube. This secondary aperture may be surrounded by a lip. Modern specimens are brown in color. SIZE: The lectotype is 0.27 mm wide across the proloculus. Paralectotypes from the Mediterranean are up to 1.9 mm in length. The width of the proloculus varies from 0.20 to 0.34 mm. SUSPECTED SYNONYMS: None verified. OBSERVED OCCURRENCES: Ammolagena clavata is a common deep-water species in the modern ocean, which also occurs in Early Cretaceous to Paleogene flysch-type assemblages. It was originally described from eight stations in the Greek Archipelago and near Crete (Jones & Parker, 1860). In the modern ocean, A. clavata appears to be most common in areas with coarse substrate. In the HMS CHALLENGER material, Brady (1884) reported it to be most common at North Atlantic stations. It was less common at stations from the South Atlantic, South Pacific and Southern Ocean, and was reported to be missing from the North Pacific stations. Its distribution in the western North Atlantic was studied by Cushman (1918), who listed it from 13 ALBATROSS stations between 196 and 1635 fathoms. Cushman noted that it was more common "in warmer waters" in the Caribbean and Gulf of Mexico than along the eastern margin of North America from Florida to Cape Cod. Lukina (1980) reported it from 780 to 5070 m in the Central Pacific near Hawaii and Samoa, and Schröder (1986) observed it between 2750 and 4925 m on the Nova Scotian continental slope and rise, but not on the Nares Abyssal Plain. We have not observed it in our samples from the Hatteras Abyssal Plain. Harloff & Mackensen (1997) reported its upper depth limit as 2600 m in the Argentine Basin and Scotian Sea. In this region it is most common between 2600 and 3400 m, in areas with low values of carbon flux (below 1.1 gC/m2-yr) KNOWN STRATIGRAPHIC RANGE: Early Cretaceous to Recent. BATHYMETRY: Predominently bathyal. It is used as an indicator for middle bathyal depths in the Gulf of Mexico, where Pflum & Frerichs reported its upper depth limit at around 500 m. Loeblich & Tappan (1987) reported its upper depth limit at 180 m in the modern ocean. Goès (1894) reported its depth range as 90 to 450 m off Scandinavia. REMARKS: The existing definition of Ammolagena Eimer and Fickert, 1899 needs to be emended to take into account the presence of a supplementary aperture. The original description of Jones & Parker does not mention the presence of a second aperture at the base of the proloculus, nor is this feature mentioned by Loeblich & Tappan (1987). The specimen figured by Loeblich & Tappan (1964) from ALBATROSS Sta. D2385 in the Gulf of Mexico (USNM 433468) does not have a secondary aperture. However, many Recent specimens from ALBATROSS stations in the USNM collections display secondary apertures which are often surrounded by a lip. Wright's (1891) colour drawing of a specimen collected in 750 fathoms off SW Ireland clearly shows a small, round second aperture surrounded by a distinct lip, and Rhumbler's (1913) colour drawing shows a second aperture which is clearly labelled. Cushman (1918) noted that both microsphaeric and megalosphaeric individuals occur, with microsphaeric specimens having a smaller proloculus and longer tubular chamber. Collins (1958) found a specimen that has a second pyriform chamber arising from the tubular extension of the first and noted "the definition of the genus should be emended to include the multilocular condition". ILLUSTRATIONS: Plate 21 - Ammolagena clavata (Jones & Parker) Fig.1a-d. Recent, Lectotype, Parker Collection (BMNH no. ZF 4873, ex Slide 1894.4.3.507), off Galita Island (Malta), Mediterranean. 1b - detail of chamber showing secondary aperture. 1d - detail of tube showing multilayered wall; Fig. 2a,b. Recent, Paralectotype, Parker Collection (BMNH no. ZF 4874, ex Slide 1894.4.3.507), off Galita Island, Mediterranean; Fig. 3. Early Eocene, ODP Site 647, Labrador Sea, specimen on Ammodiscus cretaceus, note secondary aperture surrounded by a lip; Fig. 4. Early Eocene, ODP Site 643, Norwegian-Greenland Sea, specimen on Rhabdammina cylindrica; Fig. 5. Early Eocene, ODP Site 643, Norwegian-Greenland Sea, specimen on sand grain; Fig. 6. Paleocene, Lizard Springs Formation, specimen on H. dilatata. 
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