ALBERT

Description: Two new genera and eight new species of benthic foraminifera are described from the shallow water, tropical lagoon of Madang, Papua New Guinea. The new hauerinid genus Pseudolachlanella is characterized by juvenile cryptoquinqueloculine, adult almost massiline arranged chambers, and a slitlike, curved aperture with parallel sides and a long, slender, curved miliolid tooth. Pitella haigi n. gen., n. sp. is a new foraminifera with cryptoquinqueloculine arranged chambers, an almost entirely pitted shell surface (pseudopores) and a rounded aperture with a short simple tooth. Among the other species described as new are four hauerinids and two agglutinated foraminifera All new species described here occur sporadically in the shallow water back- and forereef environments of the lagoon (0–55m), and live infaunally and epifaunally in well-oxygenated, fine and coarse grained biogenic sediments. They are absent in muddy, organic-rich, low-oxygen sedimentary environments within bay inlets where variations of salinity are considerable.

Description: Comparative studies on DNA nucleotide sequences have revolutionized our understanding of the phylogenetic relationships of many organisms and have become an important tool in evolutionary, ecological and palaeobiological inquiry. We have analysed partial small-subunit 18S sequences (srDNA) of Elphidium williamsoni (Haynes, 1973), a common intertidal benthic foraminiferid from the North Sea. The molecular phylogenetic analysis of the ribosomal rDNA sequence data indicate that E. williamsoni constitutes a well-defined genetic entity that is closely related to Elphidium aculeatum.Elphidium williamsoni is a prominent and frequently encountered foraminiferid in the North Sea and other tidal flats. It was originally described by Williamson (1858) as Polystomella umbilicata and subsequently renamed by Haynes (1973). Because of its phenotypic similarities with other elphidiids, this species has been frequently confused with, for example E. excavatum or Cribrononion alvarezianum (see Haynes for discussion). The molecular data provided here, and their direct comparison to other benthic foraminifera including one elphidiid, may therefore provide additional insight into the taxonomic status and the validity of this species.Individuals of the foraminiferid Elphidium williamsoni were collected in October 1997 from the intertidal mud flats of the Crildumersiel at the outer Jade Bay near Wilhelmshaven, North Sea (see Langer et al., 1989 for details). The mud flats are characterized by fine-grained, muddy sediments containing high contents of organic material. In the laboratory, specimens were transferred into petri dishes, examined and cleaned under a stereo microscope. Living specimens of E. williamsoni were picked out separately and placed into clean glass dishes containing filtered. . .

Description: Associations of epizoic foraminifera and invertebrates are widespread and have been reported from polar to tropical and shallow to bathyal environments (Zumwalt & DeLaca, 1980). Their fossil record stretches far back into Palaeozoic times as documented by agglutinated foraminifera attached to crinoids in Silurian and Devonian reef deposits of Morocco and Gotland (Franzen, 1974). Strong preferences for filter-feeding hosts suggest that epizoic foraminifera benefit from increased nutritional resources accumulated in the immediate flow microhabitat (Langer & Long, 1994).In the course of a broader study on foraminifera/invertebrate associations, several hundred foraminifera attached to the outer wall of agglutinated tubes of various polychaetes (e.g. Sabella sp., Potamilla sp.) were collected from sediment samples dredged at 61 m depth off the University of California, Moss Landing Marine Laboratory (NW Pacific). Attached foraminifera display a remarkable mode to obtain and differentially cement grains from the host tube that previously has not been reported. Agglutinated polychaete tubes and fragments thereof may reach 2 cm or more in length and are composed of fine sand, silt and micas cemented together by secreted organic material (Fig. 1). Tubes are typically orientated vertically in the mud and project above the sediment surface into the water column.NEW OBSERVATIONSExamination of agglutinated polychaete tubes revealed that their outer walls were commonly colonized by one to three foraminiferans (Figs 1–3, tube diameter 1.5–2.0 mm). The epizoic foraminiferal fauna comprised exclusively agglutinated taxa and included the following species: Alveophragmium advenum (Cushman), Textularia abbreviata Lalicker & McCulloch, Textularia schencki . . .