Parmales, a New Order of Marine Chrysophytes, with Descriptions of Three New Genera and Seven New Species',2
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J. Phyol. 23, 245-260 (1987) PARMALES, A NEW ORDER OF MARINE CHRYSOPHYTES, WITH DESCRIPTIONS OF THREE NEW GENERA AND SEVEN NEW SPECIES',2 Beatrice C. Booth3 School of Oceanography, University of Washington, Seattle, Washington 98 195 and HarzIej J. )\/larchant Antarctic Division, Department of Science, Channel Highway, Kingston, Tasmania 7 150, Australia ABSTRACT by Nishida (1986) and Takahashi et al. (1986). Here A neu order, Parrnales, in the Chryophyeae has cells we describe the entire group as a new order within wth szlzceous ualls rnacle up of round, trzradzate and the Chrysophyceae, an algal class with a number of sometunes oblong plates alljitting edge to edge. In the nez orders containing organisms with siliceous cell walls. farnzlj, Octolarninaceae, cell ualls haile ezght plates. Cell Unlike other siliceous organisms such as diatoms, ulalls in the neul gems Tetraparma haw four round there seems to be a wide range of variation, even plates and four trziadzate plates. Cell ualls in the new within a distinct form, in the size, length and density genus Triparma halie three round plates of equal size, of the ornamentation. For these reasons it is not one larger round plate, one trzradiate plate and three possible at this time to know if all the 21 distinct oblong plates In the neul fa,nilj, Pentalaminaceae, cell forms which have been observed to date are discrete walls hazv three round and two triradiate plates. A total species. We have therefore used the basic construc- of seim neu species andfour subspecies are described from tion and symmetry of the cell wall as conservative subarctic Pa@ and ,4ntarctic waters. characters to describe seven species, and we have described as subspecies those forms with quite dif- Kej zndex words: Antarctzc, Chryopliyeae; marzne; ferent ornamentation. The taxonomic status of the nanoplankton; North Paczfc; Parmales subspecies will hopefully be resolved by observations of cultured forms, once that is possible. Because the Nanoplanktonic siliceous spheroids of unknown cell wall is most evident in the least ornate forms, taxonomy have been reported principally from sub- we have described them as species and the more arctic and Antarctic seas (Nishida 1979, Booth et al. ornate forms as subspecies. 1980, 1981, Silver et al. 1980, Buck and Garrison 1983, Nishida 1986, Takahashi et al. 1986, Mar- MATERIALS AND METHODS chant and McEldowney 1986). These cyst-like or- The present investigation is based entirely on field samples ganisms have also been reported from the California because there has been no successful attempt to date to culture Current (Booth et al. 1982), Indian Ocean (Norris these organisms. 1971), from 2080 m depth in the equatorial Pacific North Pacific material was filtered at sea, stored on Nuclepore Ocean (Silver et al. 1980) and in Pacific Ocean sed- filters immersed in 75% ethanol at 4" C, critical point dried from iments (Stradner and Allram 1982). While it was FREON (method of Paerl and Shimp 1973, with modifications noted in Booth et al. 1980)and viewed using a JEOL-U3 scanning originally hypothesized (Silver et al. 1980) that these electron microscope. For transmission electron microscopy (whole cells were the resting stages of loricate choanofla- mounts) 2-3 L samples were concentrated over a Nuclepore filter gellates, they have recently been shown by trans- (0.8 wm pore size) to a final volume of about 2 mL. The concen- mission electron microscopy to contain chrysophyte- trate was fixed with glutaraldehyde (final concentration ca. 3%) like organelles (Marchant and McEldowney 1986). and a drop settled onto a formvar-coated grid. After 15 min the Also, that these cells have a large chloroplast and excess water was removed and the grid thoroughly dried. The dried grid was washed in several rinses of distilled water, dried apparently very little storage material suggests that and stored. Grids were shadow cast in a vacuum evaporator using they may be a vegetative rather than an encysted &7 cm of 0.203 mm diameter gold wire held in a tungsten basket stage. Their concentration in the order of lo5 cells 9 or 10 cm from the grids at an angle of 30". Grids were examined L-' makes them one of the more abundant groups using a JEOL lO0B transmission electron microscope (TEM). of phytoplankton in polar and subpolar waters. The Antarctic organisms were concentrated at sea either by cen- spatial and temporal distribution of these and other trifugation or filtration through 0.8 Pm pore size Nuclepore fil- siliceous and calcareous nanoplanktonic organisms t?rs, fixed and stored in 1% glutaraldehyde, until returned to .4ustralia when they were post fixed in 1% OsO, for 30 min, in the Southern Ocean have recently been reported dehydrated through a graded series of acetone, critical point dried, sputter-coated with -gold-and viewed using a JEOL 840 I Accpptrd: 28 ,Vo.cwnbrr 1986. scanning electron microscope. Concentratedorganisms were also * Contribution number 1671 from School of Oceanography, attached to poly-l-lysine coated glass cover slips (Marchant and University of Washington, Seattle, Washington 98 195. Th6mas 1983) and processed for scanning electron microscopy Address for reprint requests. in the same way. 245 246 BEATRICE C. BOOTH AND HARVEY J. MARCHANT individual forms and definition will depend on electron micro- graphs. RESULTS Artzficial Kej to the Parmales 1. Cell wall made up of 5 plates ..... Pentalamina 1. Cell wall made of up 8 plates .............. 2 2. Plate configuration: 4 shield plates, 4 tri- radiate plates 2. Plate configur radiate plate, 3 girdle plates, 1 ventral plate ......................... Triparma 4 Pentalamina Tetraparma Triparma 3. All plates with elongate areolae and with or without short, densely spaced papillae .... FIG. 1. Diagram of the three new genera in the new order, ..................... Parmales. S, Shield plate. T, triradiate plate. G, girdle plate. V, Tetraparma pelagica ventral plate. R, a round plate. 3. Plates smooth, with or out spines ..... ............................ Tetraparma spp. 4. Plates with elongate areolae ............ 5 Cell dimensions were taken from scanning electron micro- 4. Plates without areolae or with dense or- graphs. Arms of the triradiate plates were measured from the namentation obscuring underlying plate central hole to the end of the arm. structure ............................. 6 The original descriptions of cells of the Parmales were based 5. Areolation coarse ... Triparma columacea on a series of samples collected from the subarctic Pacific in May, 5. Areolation fine ..... Triparma retinemis 1978 (Booth et al. 1981) and from the Weddell Sea, Antarctica, 6. Plates smooth (without areolae) in February 1978 (Silver et al. 1980). The present study is based ....... as well on material collected throughout 1980 and the first half .................. Triparma laevis of 1981 from Weatherships at Sta. P (subarctic Pacific: 50" N, 6. Plates with dense ornamentation obscur- 145" W). These latter samples cover every month except May. ing underlying plate structure 7 Samples were also collected in the Alaskan Stream and Bering 7. All plates with long processes, sc Sea in August and September, 198 1, from the NOAA Ship Dis- fairly dense .................Triparma strigata cozlerer, and at Sta. P in June, 1980, 1983, from the RV T. G. 7. All plates with short, densely spaced pro- Thompson and May and August, 1984, from the RV Wecoma. As well as the samples of Parmales collected in January, 1985, from cesses .. Triparma uerrucosa Prydz Bay, Antarctica (Marchant and McEldowney 1986), a fur- ther collection was made in January and February, 1986, on a Sjstematic Part cruise along the coast of Antarctica between the Australian sta- Parmales Booth & Marchant ord. nov. tions of Mawson and Casey. (Latin: small, round shields) The original plates have been deposited at the Academy of Natural Sciences in Philadelphia (Herbarium #967378). Paries cellulae ex laminis circularibus et laminis tri- radiatis, laininis cinguli oblongis aliquando praeditus, Terminology interordinatis margine ad marginem, compositus. Terminology for the separate parts of the spherical or sub- Cell wall composed of round and triradiate plates, spherical cell wall is according to Booth et al. (1981). The ter- with or without oblong girdle plates, all fitting edge minology is reviewed here. Shield plate: a round plate with or to edge. without a central knob or processes. Four shield plates of equal Two families are recognized: The Octolamina- size are found in Tetraparma gen. nov. and three shield plates of equal size in Triparma gen. nov. (Fig. 1). Triradzate plate: a plate ceae (e.g. Figs. 2-3) with eight plates and the with three arms equally spaced, each arm fitting in between two Pentalaminaceae (e.g. Figs. 6-7) with five plates. shield plates. Four triradiate plates are found in Tetraparma, two in Pentalamina, and only one in Triparma. Ventral plate: a round Octolaminaceae Booth & Marchant fam. nov. plate of greater diameter than the shield plates and found in (Latin: eight plates) Triparma on the opposite side of the sphere from the triradiate Diagnosis: Paries cellulae ex laminis octo, quarum plate. Girdle plates; three oblong plates found only in Triparma quattuor circulares sunt, interordinatis margine ad mar- juxtaposed end to end to form a ring around the ventral plate between it and the other four plates. ginem, compositus. Ornamentation of various types (papillae, wings, spines, keels) Cell wall composed of eight plates (four of them occurred on the plates; it will be described under sections on the are round) fitting edge to edge. FIGS. 2-7. Species of Tetraparma (Figs. 2-5) and Pentalamina corona (Figs. 6-7). FIGS.2-3. Tetraparma pelagicus. FIG. 2. Three shield plates and 3 triradiate plates visible. 64"59.8'S, 83"02'E, Jan., surface. FIG. 3. Two shield plates and 2 triradiate plates visible. 67"00.1'S, 63"06.9'E, Jan., 35 m. FIG. 4. T.