169

PHYTOPLANKTON FROM THE HAURAKI GULF.

by Krystyna A . Lanigan*

I N T R O D U C T I O N

The literature on the occurrence of phytoplankton in New Zealand waters is meagre. Earlier papers with a few diagrams and species lists include Crawford (1947) and Norris (1961). Cassie (1960, 1961) has described seasonal changes in diatoms and dinoflagellates off the East Coast, together with species lists and photographs. Comprehensive diagrams and photographs of diatoms occurring in New Zealand waters appear in a series of papers by Crosby and Ferguson Wood (1958, 1959); Ferguson Wood, Crosby and Cassie (1959); and Ferguson Wood (1961, 1963). The most recent check list of New Zealand diatoms is by Taylor (1970).

The following diagrams are intended to help in identifying commonly occur­ring phytoplankton. Dimensions are given in microns and are means of ten measurements (taken in 1971). The classification of Taylor (1970) has been adopted.

C L A S S I F I C A T I O N DIVISION:CHRYSOPHYTA

C L A S S B A C I L L A R I O P H Y C E A E O R D E R B A C I L L A R I A L E S Suborder Biddulphineae

Family Biddulphiaceae:

Family Chaetoceraceae:

Suborder Coscinodiscinaceae

Family Coscinodiscaceae:

Suborder Rhizosoleniineae Family Leptocylindraceae: Family Rhizosoleniaceae:

Suborder Fragilariineae Family Fragilariaceae:

Suborder Achnanthineae

Family Achnanthaceae:

Suborder Naviculineae Family Bacillariaceae: Family Cymbellaceae: Family Naviculaceae:

DIVISION PYRROPHYTA C L A S S D E S M O K O N T A E

Family Prorocentraceae:

C L A S S D I N O P H Y C E A E

Biddulphia, Ditylum, Eucampia, Hemialus. Chaetoceras.

Paralia, Thalassiosira, Stephanopyxis.

Guinardia, Lauderia, Leptocylindrus. Rhizosolenia.

Asterionella, Thalassionema, Thalassiothrix.

Cocconeis.

Nitzschia. Phaeodactylum. Diploneis, Navicula, Pleurosigma.

Exuviaella, Prorocentrum.

'Department of Botany, University of Auckland.

O R D E R G Y M N O D I N I A L E S Family Gymnodiniideae:

O R D E R P E R E D I N I A L E S Family Goniaulacaceae: Family Ceratiaceae: Family Perediniaceae:

O R D E R D I N O P H Y S I D A L . E S Family Dinophysidae:

170

Amphidinium, Gymnodinium.

Goniaulax. Ceratium. Peredinium.

Dinophysis,

DIATOMS

Biddulphia mobiliensis

Ditylum brightwellii

a - J 40 p

Eucampia zoodiacus

171

Guinardia flaccida

172

Lauderia annulata

* I 4 6 r

Leptocylindrus danicus

Rhizosolenia alata (length, 350/i)

Rhizosolenia hebetata forma semispina

(length, 200^) Rhizosolenia styliformis

(length, 200/i)

Phaeodactylum tricornutum (length 30M)

Nitzschia closterium

(length, 50/Lt)

Nitzschia longissima (length, 100|U)

Nitzschia pseudoseriata (length, 70M)

Nitzschia pungens (length, 40/J)

174

V 1

(length, 185 AO

33// • Gyrosigma tenuissima

(Length, 200//) Navicula membranacea

175

DINOFLAGELLATES

176

Gymnodinium sp Goniaulax sp.

A C K N O W L E D G E M E N T S

I wish to thank my supervisor, Dr F . J . Taylor, for his help with identifications.

R E F E R E N C E S

Cassie, U . V .

Crawford, D . A .

Crosby, L . A . , Wood, E . J .F .

Taylor, F.J .T.

Wood, E.J .F .

Wood, E.J .F . , Crosby, L . H . , Cassie, V .

1960 Seasonal changes in diatoms and dinoflagellates off the east coast of New Zealand during 1957 and 1958. N.ZJ.Sci. 3: 137-72.

1961 Marine phytoplankton in New Zealand waters. Bot. Marina 2 (supp.): 1-54.

1947 A phytoplankton season in Cook Strait. Roy. Soc. N.Z. Rep. 6th Cong. 77: 173-5.

1958 Studies on Australian and New Zealand diatoms. I. Plank-tonic and allied species. Trans. R. Soc. N.Z. 88: 483-530.

1959 Studies on Australian and New Zealand diatoms. II. Normally epontic and benthic genera. Trans. R.Soc. N.Z. 89: 1-58.

1970 A preliminary annotated check list of diatoms from New Zealand coastal waters. Trans. R. Soc. N.Z. (Biol.Sci.) 12: 153-74.

1961 Studies on Australian and New Zealand diatoms. IV. Descrip­tions of further sedentary species. Trans. R. Soc. N.Z. 88: 669-98.

1963 Studies on Australian and New Zealand diatoms. V I . Tropical and subtropical species. Trans. R. Soc. N.Z. (Bot.) 2: 189-218.

1959 Studies on Australian and New Zealand diatoms. III. Descrip­tions of further discoid species. Trans. R. Soc. N.Z. 87: 211-9.