PYRRHOPHYTA (DINOFLAGELLATA)Ciri-ciri umum: Unicellular Memiliki sepasang flagel yang tdk sama panjang Kosmopolitan Ada tipe holofitik dan holozoik Ada yg parasit, saprofit

In 1753 the first modern dinoflagellates were described by Baker and named by Muller in 1773. The term derives from the Greek word (dinos), meaning 'whirling,' and Latin ''flagellum'', a diminutive term for a whip or scourge.

These same dinoflagellates were first defined by Otto Btschli in 1885 as the flagellate order dinoflagellida. Botanists treated them as a division of algae, named Pyrrhophyta ("fire algae"; Greek pyrrhos, fire) after the bioluminscent forms, or Dinophyta.

Pigmen yang dimiliki : Chlorofil a, c,

Carotene, Xanthofil (peridinin, neoperidinin, dinoxanthin, neodinoxanthin, diatoxanthin Ada berdinding tebal (theca) terbuat dari selulosa, ada tdk berdinding Inti sel merupakan peralihan antara prokariot dan eukariot (eukariot yang primitif) Jumlah spesies +/- 2100

KlasifikasiAda 2 kelas: 1. Desmophyceae memiliki flagel yang keluar dari ujung anterior (apical, subapical) Motil Memiliki 1 ordo : Prorocentrales

Memiliki dinding sel yang tebal, tersusun atas dua belahan (theca) Berbentuk speris, oval, atau tetes air mata (teardrops) Terdapat di air tawar, payau, laut Contoh genus Prorocentrum 2. Dinophyceae flagelnya keluar dari posisi ventral. Satu flagel terletak pada bagian sulcul, yg lainnya pada bag cingulum

Memiliki anggota lebih banyak Salah satu flagella terdpat pd bagtransversal, yg lainnya pd bag longitudinal Memiliki 6 ordo: 1. Dinophysiales 2. Gymnodiniales 3. Noctilucales 4. Peridiniales 5. Gonyaulucales 6. Pyrocystales

Ordo DinophysialesBersifat motil Hidupnya soliter Memiliki dinding sel Berbentuk pipih lateral Mempunyai tutup cingulum pada bagian ujung anterior Epitheca pendek Menghasilkan toksin Contoh genus Dinophysis, Ornothocercus

Ordo GymnodinialesSel motil Tidak memiliki dinding sel Berbentuk oval Memliki girdle berbtk spiral Kosmopolitan Beberapa diantaranya holozik Tidak menghasilkan toksin Contoh genus Gymnodinium, Amphidinium

Ordo NoctilucalesBerukuran besar (makroplankton) sampai 2 mm berbentuk bola Tidak berdinding sel Menghasilkan cahaya bioluminescent Memiliki vacuola besar berperan sbg pelampung Pada umumnya holozoik, hidup di air Laut Memiliki tentakel panjang Tidak menghslkan toksin Contoh genus Noctiluca

Ordo PeridinialesBerdinding sel tidak dapat berubah-ubah Motil Holozoik, sebagian besar hidup di laut Beberapa spesies memiliki tanduk Contoh genus Peridinium

Ordo GonyaulacalesMemiliki dinding yang keras Menghasilkan cahaya Kosmopolitan

Epitecha membentuk sebuah tanduk, hipotheca membentuk dua atau tiga tanduk Mengalami cyclomorfosis Sebagian besar holofitik Contoh genus Ceratium, Gonyaulax

Ordo PyrocystalesMemiliki bentuk speris, bulan sabit Menghasilkan cahaya

Pada umumnya holofitik Dinding sel tebal tersusun atas dua lapis (atas sporopellenin, bawah selulosa) Contoh genus Pyrocystis REPRODUKSI Metode Utama ( normal) Pembelahan sel biasa dengan arah transversal, longitudinal, oblique

Metode lainSeksual isogamus (lebih sering), anisogamus (jarang) Pembentukan resting kista BIOLUMINESCEN DAN CIRCADIAN Hanya terdapat pada spesies yang di laut Organisme yang menghslkannya Noctiluca, Gonyaulax, Pyrocystis, Pyrodinium, Peridinium

Bioluminescence, emission of light from living organisms, without appreciable heat. The light results from a chemical reaction mediated by enzymes and involving specialized phosphorus-containing molecules in the organisms. Bioluminescence is found in species of bacteria, algae, fungi, and invertebrate animals. Some deep-sea fish are equipped with organs that produce luminescence to which prey is attracted.

RED TIDE DAN TOKSINKategori toksin yang dihasilkan 1. Membunuh ikan dan sedikit invertebrata 2. Membunuh invertebrata 3. Membunuh sedikit organisme , tapi toksin yang dihasilkan terkonsentrasi dalam spihon atau alat pencernaan moluska Toksin yg dihslkan Saxitoksin (neurotoksin) toksisitasnya 100 000 kali kokain

Dinoflagellates sometimes bloom in concentrations of more than a million cells per millilitre. Some species produce neurotoxins, which in such quantities kill fish and accumulate in filter feeders such as shellfish, which in turn may pass them on to people who eat them. This phenomenon is called a red tide, from the color the bloom imparts to the water.

Organisme penyebab red tide 1. Prorocentrum 2. Gymnodinium 3. Gonyaulax 4. Ceratium 5. Trichodesmium eritreumPengaruh toksin Kelumpuhan (paralytic), Gangguan syaraf (neurotic), hilang ingatan (amnetic), mencret (diarrhetic) Yg terbanyak adl PSP dan DSP

Ceratium

Peridinium

Bioluminescens

Noctiluca is not photosynthetic. It preys upon phytoplankton, and sometimes other microscopic organisms. This cell contains several separate food vacuoles (arrows), each containing a different diatom colony. The genera Thalassiosira and

PERANAN

(+) Produsen primer no 2 di laut (+) Makanan ikan (-) Jika terjadi red tide (-) Kompetitor bagi ikan dalammemperoleh fitoplankton dan oksigen (???)

often photosynthetic protists, commonly regarded as "algae" (Division Dinoflagellata). They are characterized by a transverse flagellum that encircles the body (often in a groove known as the cingulum) and a longitudinal flagellum oriented perpendicular to the transverse flagellum. This imparts a distinctive spiral to their swimming motion. Both flagella are inserted at the same point in the cell wall, by convention defining the ventral surface. This point is usually slightly depressed, and is termed the sulcus. In heterotrophic dinoflagellates (ones that eat other organisms), this is the point where a conical feeding structure, the peduncle, is projected in order to consume food. Dinoflagellates possess a unique nuclear structure at some stage of their life cycle - a dinokaryotic nucleus (as opposed to eukaryotic or prokaryotic), in which the chromosomes are perminently condensed. The cell wall of many dinoflagellates is divided into plates of cellulose ("armor") within amphiesmal vesicles, known as a theca. These plates form a distinctive geometry/topology known as tabulation, which is the main means for classification. Both heterotrophic (eat other organisms) and autotrophic (photosynthetic) dinoflagellates are known. Some are both. They form a significant part of primary planktonic production in both oceans and lakes. Most dinoflagellates go through moderately complex life cycles involving several steps, both sexual and asexual, motile and non-motile. Some species form cysts composed of sporopollenin (an organic polymer), and preserve as fossils. Often the tabulation of the cell wall is somehow expressed in the shape and/or ornamentation of the cyst.