155

REVIEW ARTICLE

A Note on Paleobotany of Mangroves
Motohiko KOGO* and Kiyomi KOGO
Action for Mangrove Reforestation
3-29-15-1101, Honcho, Nakano, Tokyo 164-0012, Japan*e-mail: actmang@big.or.jp

Abstract
There is little published research on the paleobotany of mangroves. According to Rollet (1981), from
1600-1975 the number of papers on the topic was 126, which was 2% of the 5,653 papers on mangrove research published in that period. Research on mangrove paleobotany since 1976 has also been minimal. We
collected and reviewed papers on the paleobotany of mangroves, visited museums to obtain information on
fossils, mainly pollen, and analyzed the collected data. The results are described below.
The first mangroves appeared during the Upper Cretaceous era, 100-65 million years ago (mya). The
evolution of mangroves is thought to have been strongly related to sea-level change (transgression-regression
cycles) in geological times. Some woody angiosperms growing in freshwater swamp forests succeeded at
growing in tidal areas and acquired salinity tolerance when the vast extent of those areas underwent marinetransgression. That event happened not only once but likely several times after the Upper Cretaceous, andeach time the biodiversity of mangroves became richer. The origin of present mangroves can be divided into
two groups, the Old and New (Worlds, and we predicted that the two mangrove groups could also be found in
the period of the Upper Cretaceous. There were several questions we could not resolve, for example, how the
expansion of their distribution proceeded. Mangrove propagules are spread by sea currents and they expand
their habitats. The world’s seas were connected during the time from the Upper Cretaceous, when the firstmangroves appeared, to the Miocene, when the Tethys Sea closed. Nevertheless, we assume that for over
80 million years, the Old and New Worlds did not mix. Genetic research on the migration and evolution ofmangroves will be essential for complementing fossil studies.
Key words: New and Old Worlds, origin of mangroves, paleobotany, Tethys Sea,
Upper Cretaceous-Miocene

1. Introduction
Our efforts at developing mangrove plantations dateback to 1978. In the first ten years we developed mangrove plantation technology by creating experimental
plantations along the coasts of the Arabian Peninsula,
mainly in Saudi Arabia and the United Arab Emirates(UAE). We were successful at developing the technology
for growing mangroves in arid coastal areas. Since 1993,
mangrove reforestation and conservation activities havebeen conducted in Vietnam, Myanmar and Ecuador. In
addition to conducting such activities, we have visitedmangrove areas all over the world (Fig.1 and Table 1).
Very recently we became interested in the paleobotany of mangroves. The reason for this interest was
our visit to Wadi el Hitan in the Western Desert of Egypt
in May 2009. Not a single plant could be seen in thedesert—it was like the surface of the moon—but it wasthere that we found an inlet of the Tethys Sea from the
Eocene epoch (ca. 40 mya). In this area we found several
fossilized whale bones from the Eocene and also some
Global Environmental Research
17/2013: 155-163
printed in Japanfossils which were said to be mangrove roots.
The next year, in February 2010, we again visited
Egypt with five Japanese scientists, each from different
academic fields. Prof. Moustafa M. Fouda, adviser to the
Ministry of State for Environmental Affairs, Egyptian
Environmental Affairs Agency, Nature Conservation
Sector, kindly supported us as he had in the previous year.
Some paleontological scientists belonging to the Nature
Conservation Sector guided us to the fields. We surveyed
three sites, Bahariya, Wadi el Hitan (Muller & Burns,
2010) and Qatrani. Bahariya is where Ernst Stromer had
found dinosaur fossils (Tyrannosaurus rex, Palarititan
stromeri ） in 1914-1915. It was known, based on ashellfish fossil study, that this place was the coast of theancient Tethys Sea in the Upper Cretaceous (ca. 100-65
mya). When we visited the Egyptian Geological Museumin Cairo, we saw fossilized Avicennia leaves collectedfrom Bahariya. According to Darwish and Yousry (2007),the fossil was dated to 97 mya, within the Upper
Cretaceous. If their identification could be confirmed, thefossil would be the oldest mangrove fossil ever found.
©2013 AIRIES

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M. KOGO and K. KOGO

Fig. 1 Research and reforestation activities of Kogo of the Al Gurm Research Centre/Action for
Mangrove Reforestation (Actmang) and his colleagues, 1978-present.

Table 1 Main mangrove-related activities carried out by the Al Gurm Research Centre/Action for Mangrove Reforestation(Actmang).
Year
1978 - 1991
1985 - 1987
1990 - 1992
1993
1993 - 2002
1993-present

Main activities on mangroves
Establishment of techniques for mangrove plantation along desert coasts. Experimental plantation
carried out in Kuwait, Saudi Arabia, UAE, Oman and Pakistan.
Research on restoring mangrove forests in the Truk Islands, Pakistan and Bangladesh requested
by UNESCO.
Establishment of techniques for mangrove plantation in Myanmar, as requested by UNDP/FAO.
Provision of advice on mangrove reforestation requested by Muscat Municipality, Oman.
Conservation of mangrove ecosystems in Ecuador.
Mangrove reforestation support to local people in Vietnam and Myanmar.

Our interest increased more than ever.
To further investigate worldwide mangrove paleobotany we visited many natural history museums
around the world, for example, the Natural History
Museum in London, the Field Museum in Chicago, theNatural History Museum in New York, the Royal Tyrrell
Museum of Palaeontology in the Badlands of Alberta,
Canada, and the Natural History Museum in Tokyo.
Since this study was based on geological and ecological uniformitarianism, we define first of all, the term“mangroves.” Then we describe results of our analyses,
mainly from reviews of the literature and the fossil record.
Finally we remark on our expectations for further studies
in this field.
“Mangrove” is not the name of a single plant, but ageneric term. Mangrove forests are plant communities
which occur in intertidal areas in the tropical and subtropical zones. They have characteristic tropical floras,
hygrophytes and halophytes. Another unique characteristic is that they transfer their propagules by sea currents and spread their habitats. Mangroves mainlycomprise woody angiosperm species, with no conifer
species, and a few palm and fern species. Also mangroves are divided into two groups, mangroves andmangrove associates. This classification, however, is notclear as there are several different opinions taken bydifferent scientists. This study focuses exclusively on“strict or true mangroves” (our classification approximately following Tomlinson, 1986), but not mangrove
associates.
There were two objectives to our research: 1) to findthe origin of mangroves, i.e., when, where and why they
appeared in geological time; and 2) to ascertain when andwhy their distribution was divided into Old World mangroves (which occur in Asia, Oceania and the east coastof Africa), and New World mangroves (which occur
in the Americas and west coast of Africa). (Fig. 2 andTable 2)

2. Methods
We carefully analyzed the mangrove paleobotanyliterature and examined the fossil record. For our literature search up to 1975, we used the bibliography by
Rollet (1981). There were only 126 mangrove paleobotany studies, accounting for 2% of the total numberof 5,653 mangrove studies listed in this bibliography(Table 3). There was no complete bibliography like

A Note on Paleobotany of Mangroves

157

Fig. 2 Distribution of mangroves, New World group (American continent and west coast of
Africa, 7 genera in 6 families) and Old World group (East coast of Africa, Asia and Oceania,
23 genera in 15 families), arranged from Tomlinson, 1986 and Spalding et al., 1997.
Table 2 Genus and species of mangroves distributed in old andnew worlds (arranged from Tomlinson, 1986 andSpalding et al., 1997).
Genus name
Acanthus
Acrostichum
Aegicealitis
Aegiceras
Avicennia
Bruguiera
Camptostemon
Ceriops
Conocarpus
Cynometra
Diospiros
Dorichandrone
Excoecaria
Heritiera
Kandelia
Laguncularia
Lumnitzera
Mora
Nypa
Osbornia
Pelliciera
PemphisRhizophora
Scyphiphora
Sonneratia
Tabebuia
Xylocarpus
Total

Number of species
Old World
New World
2
2
2
2
2
5
3
6
2
3
1
1
1
1
2
3
1
1
3
1
1
1
1
1
6
3
1
8
1
2
51 spp. in 23
12 spp. in 7
generageneraTable 3 Number of papers on mangroves paleobotany 1600-1975(arranged from Rollet, 1980).
PeriodCretaceous
Tertiary

Epoch
Upper
Paleocene
EoceneOligocene
MiocenePliocene

Quaternary
Pleistocene
Holocene
Total

No. of papers
8
18
1
49
5
13
2
7
7
16
126

Rollet’s for the post-1976 period. Studies such as
Spalding et al. (1997) and Plaziat et al. (2001) have also
noted few recent mangrove paleobotany publications. We
assumed that few scientists were interested in the
paleobotany of mangroves.
In interpreting the fossil record, we found two competing explanations as to how mangroves came to exist ina given area. One was that terrestrial plants acquired salt
tolerance to survive in brackish areas and became theancestors of the mangroves in their place of origin where
their fossils were deposited, and the other was that theymigrated from their place of origin by expansion of theirdistribution through a long drift after they had alreadybecome ancestral mangroves. The latter idea gained support from our planting experience in Khafji, Saudi
Arabia: We were trying to keep Rhizophora propagules
vital longer at our station. When they were kept in sea
water (4% salinity), they retained their ability to germinate for more than half a year. Based on our observation,
we surmised that when the propagules traveled by tidal
currents in the condition of floating on seawater andbeing shaken by waves, their ability to germinate may
have lasted longer. Their ability to germinate might bemaintained much longer than we found in our experiment.
Therefore, propagules might have been able to migrate
long distances from their place of origin to the places
where their fossils were found. However, the sea currents
during geological times are not known. We hope that our
hypothesis will be supported when data on sea current
patterns in geological times become available.

3. Results and Discussion
3.1 Mangroves and environmental change in geological times
The fossils recorded in each geological time from theUpper Cretaceous to the Miocene (100-7 mya）are shownin Fig. 3. The records from the Pliocene to the Holocene(7 mya-recent) are not shown, because there are few
records.
The transition of continents, oceans and currents during these epochs shown in Fig. 4 is predicted to have had
a strong relationship with the expansion of mangrove
distribution. Also, climates and characteristic organisms
in geological times are shown in Table 4.
Recorded mangrove fossils consist mostly of pollen(or spores in the case of the fern Acrostichum), while

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M. KOGO and K. KOGO

Fig. 3 Global distribution of mangrove fossils found from the Cretaceous to Miocene (data from
Rollet, 1981; Tsuda et al., 1986; Spalding et al., 1997 and Darwish and Yousry, 2007).

there are few leaf, stalk, root, fruit and seed fossils. As far
as we were able to determine, only twelve genera out of
22 extant mangrove genera identified have been recorded; the ten remaining genera have yet to be recorded(Table 5).
It is assumed that the number of fossil records depends on the number of scientists in those fields or theirresearch activities. Most scientists in mangrove paleobotany have worked in developed countries such as
Europe, the USA, Australia and Japan. For instance, in
Britain, four genera of mangrove fossils have been recorded because not only have there been many scientists,
but also many active studies concentrating on “London
Clay fossils” (Collinson, 1983; Kenrick & Davis, 2004).
In Japan, eight genera, the greatest number among thestudies, have been reported. It is said that those results
were made by long-term efforts carried out by threescientists, K. Tsuda, J. Itoigawa and T. Yamanoi (Tsudaet al., 1986). There are very few fossil records in Asia,
except Japan; and Africa, except Egypt and Nigeria, due
to fewer opportunities for research on fossils.
• The Upper Cretaceous (100-65 mya)
Since this period was warm, the sea was remarkably
larger. At the end of the period, however, the sea area
decreased because of cold weather. It was reported thatfrom the middle of the Upper Cretaceous, angiosperms
flourished (Stewart & Rothwell, 1993). We believe thatthe first mangrove appeared during this period, because
the oldest mangrove fossils found so far have been
Avicennia leaves (97 mya) in Egypt (Darwish & Yousry,
2007) and Nypa pollen (69 mya) in Brazil (Spalding et al.,1997).
The countries where fossils have been found are
Sarawak, Malaysia, in Asia; Czechoslovakia in Europe;
Egypt in Africa; Australia in Oceania; the USA in North
America; and Guiana in South America.
Mangrove fossils found in this period consist of fivegenera from five families, Avicennia in Avicenniaceae,
Nypa in Palmae, Pelliciera in Pellicieraceae, Acrostichum in Pteridaceae and Conocarpus in Combretaceae.
Usually mangrove fossils are identified only at the genus
level because of difficulty in identifying species, andthose may not be the same as present species anyway.
These fossils were recorded in different parts of the world
but still in limited numbers.
• The Paleocene (65-54 mya)
Paleocene mangrove fossil records include only Nypa
in Nigeria and Brazil. Such few records may be due toglobal cooling at the end of the Upper Cretaceous, which
is known as the time of dinosaur extinction. Mangroves
might have survived, however, in tropical areas near theequator. It is expected that mangrove fossils will be foundin that area.

A Note on Paleobotany of Mangroves

159

Table 4 Climate and characteristic organisms in geological times(arranged from Stewart and Rothwell, 1993).

1: Drake Strait Open (25 mya)
2: Tethys Sea close (18 mya)
3: Panama Strait Close (5 mya)

Fig. 4 Transformation of continents, oceans andcurrents from Lower Cretaceous to Miocene(from van Andel, 1985).

Period/Epochmya

ClimateCharacteristic organisms, etc.

Upper
Cretaceous
Paleocene

100-65

Warm to cold

65-54

Angiosperms rise to dominance.
Extinction of Dinosaurs.
Cenozoic type organisms.

Eocene54-38

Oligocene

38-26

Miocene26- 7

Pliocene

7- 2,5

Pleistocene

2.5-0.5

Holocene

0.5present

Warm, cooler
than Eocene
SubtropicalDistinctive forests in northern andclimate withsouthern latitudes. Many genera
heavy rainfall of Angiosperms became extinct
with new, more modern types
appearing.
Mild
Widespread occurrence of now
temperate
relic taxa (Metasequoia,
climateCercidiphyllum) in higher
latitudes.
Climatic
Restriction of broad-leaved
cooling
evergreens to lower latitudes.
Establishment of present-day
forest associations.
Warm to cold Climatic changes in temperate
latitudes allowed spread ofgrasslands.
Cold (Ice age) Almost the same as modern
organisms.
Appearance of modern man.

• The Eocene (54-38 mya)
The Eocene Epoch was a time of warm or tropicalclimates across the whole earth. It is assumed thattemperate flora flourished even in the present Arctic
Circle. Mangrove fossils have been reported from seven
genera of four families. Those are Laguncularia in
Combretaceae; Acrostichum in Pteridaceae; Bruguiera,
Ceriops, Kandelia and Rhizophora in Rhizophoraceae;
and Sonneratia in Sonneratiaceae. In addition to the fivegenera of five families found in the Upper Cretaceous, a
total of twelve genera in nine families of mangrove fossils have been recorded up to the Miocene Epoch.
The countries where the fossils were found are listed
below: they are much more numerous than those of theUpper Cretaceous.
- Europe: UK, Belgium, France, USSR (Odessa,
Turkmenia, Ukraine)- Asia: India, Malaysia (Malaya, Sarawak)- Oceania: Australia, PNG- Africa: Egypt, Libya, Senegal- North America: USA (Alabama, Georgia, Kentucky,
Mississippi, Carolina, California, Tennessee, Texas)- Middle and South America: Mexico, Panama,Jamaica, Puerto Rico, Columbia, Venezuela
It is thought that mangroves were at their prime during this period.
• The Oligocene (38-26 mya)
The climate of the Oligocene is thought to have been
mildly temperate. It is said that organisms characteristicof the Miocene tended to decline, and modern types
flourished.
Mangrove fossils have been found in four countries/

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M. KOGO and K. KOGO
Table 5 Mangrove fossils found in the Old and New Worlds (arranged from Rollet, 1981; Tsuda et al., 1994; Tomlinson, 1994;
Spalding et al., 1997; Plaziat et al., 2001 and Darwish and Yousry, 2007).
Genus name

Acrostichum
Aegicealitis
Aegiceras
Avicennia
Bruguiera
Camptostemon
Ceriops
Conocarpus
Excoecaria
Heritiera
Kandelia
Laguncularia
Lumnitzera
Mora
Nypa
Osbornia
Pelliciera
PemphisRhizophora
Scyphiphora
Sonneratia
Xylocarpus
Total 22 genera

-

UPP
○
○
○
3

Old Continent
PAL
EOC
○
○
○
○
○
○
○
○
1
7

OLI
○
○
-

MIO
○
○
○
-

-

○
○
○
5

-

-

○
○
○
○
○
○
9

-

-

UPP
^
○
○
○
○
4

New Continent
PAL
EOC
OLI
○
？
○
○
○
○
○
○
○
- ○
○
1
7
2

MIO
○
-

-

-

○
○
-

-

○
○
5

UPP: Upper Cretaceous, PAL: Paleocene, EOC: Eocene, OLI: Oligocene, MIO: Miocene
Genus name in light green: cosmopolitans, in white: old continent mangroves, in light pink: new continent mangroves-: mangrove fossils not foundregions: an unidentified genus in Borneo, Asia;
Sonneratia in Australia, Oceania; Acrostichum (disputed)
in Hungary, Europe; and Pelliciera and Rhizophora in
Puerto Rico, Middle America.
• The Miocene (26-7 mya)
The climate was warm and wet, and becoming cooler
and more arid in the late Miocene. The Tethys Sea still
extended up to the area where Europe currently is.
Mangrove fossils have been found in nine countries/regions as listed below:
Asia: Borneo (genius not identified),
Oceania: Sonneratia in Australia, and an unidentified
genus in the Marshall Islands,
Europe: Acrostichum in Poland,
Middle and South America: Pelliciera and Rhizophorain Brazil and Colombia, Avicennia in Colombia, Laguncularia in Cuba, Avicennia in Trinidad and Rhizophora in
Puerto Rico.
• The Pliocene-Holocene (7 mya-recent)This epoch extended over 7 million years. We assume
that the interests of scientists have not been focused on
mangroves, and their main themes might have been
sea-level change related to mangrove habit evolution andso on, because in Rollet (1981) there are few papers citedon the Pliocene-Holocene. We found one paper on
Avicennia, Conocarpus and Rhizophora in Trinidad, twopapers on mangrove paleobotany of the Pliocene, andtwo papers on Conocarpus in Cuba and Avicennia/
Conocarpus/ Rhizophora in Trinidad in the Pleistocene.
Even in the ice ages of the Pleistocene, however, we
suppose that mangroves flourished around the equator.

4. Concluding Remarks
4.1 Reasons plants become mangroves
As mentioned above, the first mangroves appeared in
the Upper Cretaceous. It is thought that there were four
reasons for the evolutionary origin of mangroves in that
period.
The first of these was the prevalence of woody angiosperms. Most of the early mangrove species were woody
angiosperms except for Acrostichum. This period was thetime of the Cretaceous Transformation, when angiosperms were eminently flourishing. This was a prerequisite condition.
The second was a tropical climate. Generally thisperiod was warm, except for a reduction in temperatures
after the giant meteor crashed into the earth (which led tothe dinosaur extinction). Mangroves, it must be remembered, are tropical plants.
The third was sea-level change (transgression and regression). It is thought that the direct reason for thetransformation of terrestrial plants into mangroves was
sea-level change. Sea levels in the Upper Cretaceous
were more widely varied than at any other geologicaltime. The sea extended its reach, but at the end of theepoch, tropical plant distributions decreased due tocoldness. It is thought that such a phenomenon (transgression and regression) happened not only once. It isestimated to have repeated several times during the
35 million years of the Upper Cretaceous. Huge tidal land
areas remained even after regression. Over the course oftime, woody angiosperms which acquired salt tolerance
successfully extended their habitats as niches in coastal
tidal lands.

A Note on Paleobotany of Mangroves

The fourth reason was hygrophytic adaptation.
Marine organisms have evolved to occupy land via fresh
water wetlands, but mangroves migrated from the land to
the sea, which is thought to be an easier adaptation. The
ancestral plants which evolved into mangroves might
have grown in coastal swampy forests near tidal areas.
As mentioned above, based on fossil records, fivegenera in five families of mangroves appeared in theUpper Cretaceous and an additional seven genera in fourfamilies appeared in the Eocene. We assume that thosewhich evolved into mangroves increased after the Eocene
so that the biodiversity of mangroves became richer.
At the present time, the highest diversity of mangrove
species in the world occurs in Southeast Asia. Many
mangrove species may have arisen here in geologicaltimes, and it is possible the first mangroves appeared inthis region. There are still very limited fossil data toverify this idea and further studies are anticipated in the
future.
4.2 Origins of Old and New World Mangroves
Modern mangroves are divided into two majorgroups: Old and New World mangroves. We hypothesizethat the origins of mangroves go back to the Upper Cretaceous, the same period in which the oldest mangrove
fossils are found.
Why did these two groups occur? We reply that theanswer is not simple, because many things happened
during geological history, but we suppose that angiosperms growing in wetlands near sea shores faced selective pressure to evolve salinity tolerance. We assume thatthe three genera of Avicennia, Nypa and Rhizophora
occurring along the Tethys Sea coasts might be ancestorsof the Old World mangroves, and the four genera of
Avicennia, Nypa, Pelliciera and Rhizophora occurring
along America’s coasts might be ancestors of the New
World mangroves (Fig. 3), but this should be verified.
Fossils of Rhizophora have been found on both
continents, including Czechoslovakia in Europe and the
USA in North America. Modern Rhizophora varieties
occur in both the Old and New Worlds, but as different
species. Since Rhizophora was recorded in both Worlds,
the ancestral genus must have occurred before the separation of the Old and New Worlds, and then evolved independently after the separation. Incidentally, there are five
Old World species of Rhizophora: R. apiculata, R.
mucronata, R. stylosa, R. x lamarckii and R. x selala, andthree New World species: R. harrisonii, R. mangle and R.
racemosa.
The same idea applies in the case of Avicennia.
Fossils of Avicennia occurring along Tethys Sea havebeen found in Egypt from the Upper Cretaceous, and inAustralia from the Eocene; and those occurring along thecoasts of America have been found in the USA from the
Eocene.
Modern Avicennia species also differ between the Old
and New Worlds. After separation of the continents, theancestral species evolved into five species in the Old
World: A. alba, A. integra, A. marina, A. officinalis, and161

A. rumphian; and three in the New World: A. bicolor, A.
germinans and A. schauerian.
Mangroves on the western coast of Africa are categorized as New World mangroves, but there is almost norecord of mangrove fossils in that region. We tried to
explain mangrove distribution from the data of Nigeria
and Cameroon in West Africa having records of mangrove fossils (Ellison et al., 1999).
There are a few papers on Nypa fossils in the Upper
Cretaceous in Nigeria (Germeraad et al., 1968) and
Cameroon (Salard-Cheboldaeff, 1981), as well as Nypa
fossils in the Paleocene and Eocene, and Rhizophora
fossils in the Oligocene and Miocene. What do these data
indicate? The paleo-Atlantic Ocean between Americaand Africa grew as the continents divided during theUpper Cretaceous. The mangroves occurring in West
Africa since the Paleocene have possibly been of American origin. Mangroves may have migrated from America
through the current circulation of the Paleo-Atlantic
Ocean.
There are several questions not resolved. Mangrove
propagules are spread by sea currents, and then they
expand their habitats. The seas of the world were connected during the time from the Upper Cretaceous, when
the first mangroves appeared, to the Miocene when the
Tethys Sea closed (Fig. 4). We assume that for over
80 million years, mangroves of the Old and New Worlds
did not mix. For example, neither fossils nor present
species of Conocarpus or Pelliciera are found in the Old
World, centrally, and neither Bruguiera nor Heritiera
have been found in the New World, but Pelliciera was
widely distributed along the Tethys Sea (Ellison et al.,1999).
Since there has been very little research on mangrove
paleobotany we need to apply new methods to answer
questions about ancient mangroves. We believe thatgenetic research on migration and evolution is essential
for complementing fossil studies. On the subject ofmodern mangroves, for example, comparative studies areneeded on Acrostichum, Avicennia and Rhizophora
which are distributed in both Worlds. We hope that if
someone will continue this kind research, the origin andexpansion of the distribution of Old and New World mangroves will become clear before long.
Genetic research on fossils is also important. We
therefore hope that if DNA can be extracted from fossils,museums around the world might provide fossil materials
for extracting DNA. Well preserved fossils of Nypa fruits
and Ceriops propagules found in London Clay are kept in
the Natural History Museum in London. A leaf impression of a 97 mya Avicennia is kept in the Geology
Museum in Cairo.
We look forward to the frontiers of paleo-molecularbiology being extended. The mangrove fossils listed inTable 5 are found in New and Old World continents.
Figure 5 shows photos from our travels to Egypt andLondon in 2009 and 2010.

162

M. KOGO and K. KOGO

A)

B)

C)

D)

E)

F)

G)

H)

I)

J)

K)

L)

Fig. 5 Our travels in the Western Desert of Egypt and in London in 2009 and 2010.
A) Fossil of Dorudon atrox, an ancient whale, in Wadi al Hitan.
B) It is said that this is a fossil of mangrove root system.
C) Nummulitidae, an indicator of the Eocene.
D) Second research team, 2010.
E) Stromer found dinosaur fossils on the hill.
F) Scenery of a corner of the Bahariya depression.
G) Impression of a lotus leaf found.
H) Fossils of seashells, evident of the Tethys sea.
I) Impression of an Avicennia leaf, 97 mya.
J) Mr. K. Ishikawa, Japanese Ambassador, and Prof. M. Fouda, Ministry of the Environment, joined us at Wadi al Hitan in 2010.
K) Dr. P. Kenrick showed us fossils of London clay fossils at the Natural History Museum, London, 2010.
L) Fossil of Ceriops propagule found in London Clay.

A Note on Paleobotany of Mangroves

Acknowledgements
We really appreciate the support and advice of many
people for this study. Their names are mentioned below
with our great gratitude (in random order, prefixes andtitles omitted).
In Egypt: Moustafa M. Fouda, Kaoru and Akiko
Ishikawa, Yasuaki Nakamura, Abdelwahab Afefe
Abdelwahab, Ms. Hala, Mohamed Taalat, Gabely Abul
Khair, Mohamed Sameh Antar, Ahamed Salama
Mohamed, Ahamed Awad, Isamu Yamada, KazuhikoMiwa, Hiroshi Nawata, Kyoichi Tomita and Shun
Ishiyama, In the UK: Paul Kenrick. In the USA: Ryosuke
Motaini, In Japan: Karyu Tsuda, Junji Itoigawa, Koshiro
Kisaki, Kazuhiko Uemura, Tomoyoshi Kase, Toyohiko
Miyagi, Kunio Suzuki, Shigeyuki Baba, Sadao
Kawaguchi, Keiji Matsuoka and Akira Komiyama.

163

Spalding, M, M. Kainuma and L. Collins, eds. (2010) World
Mangrove Atlas. International Society for Mangrove Ecosystems, Okinawa.
Stewart, W.N. and G.W. Rothwell (1993) Paleobotany and the
Evolution of Plants, Second Edition. Cambridge University
Press.
Tomlinson, B.P. (1986) The Botany of Mangroves. Cambridge
University Press.
Tsuda, K., J. Itoigawa and T. Yamanoi (1986) Mangrove Swampfauna and Flora in the middle of Miocene in Japan. Paleontology
Science Japan, S.P., 29: 129-134.
van Andel, T.H. (1985) New Views on an Old Planet, Continental
Drift and the History of Earth. Cambridge University Press.
(translated into Japanese by T. Uda, 1987, 1991. Tsukiji Shokan,
Tokyo).

Motohiko KOGO

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Motohiko KOGO established the Exploration Clubat the Tokyo University of Agriculture when he
was a student. In 1962-1963, he organized andjoined a Himalayan expedition (exploring the areafrom the Barun Glacier to the Kangchenjunga
Glacier and attempting to climb Mt. Twins,
7,350m, in Eastern Nepal). He has been studying
mangroves since 1978. He successfully pioneered
development of mangrove plantation technology on the Arabian coast in
1978-1991. Books he has written include Alone in the Himalayas (inJapanese, 1964) and The Green Adventure, Growing Mangroves along theCoasts in Arabia (in Japanese, 1988) among others. Prizes he has received
include the Rolex Award for Enterprise (1987), NIKKEI Award for theTechnology of Global Environments (1994), and others. He loves
adventure in various fields, including academic.

Kiyomi KOGO
Kiyomi KOGO is a research fellow at Action for
Mangrove Reforestation (an NGO). She received
her M.Sc. (1967) in Geography at the Universityof Tokyo. She has been a writer, editor andpart-time lecturer at many universities, including
University of Tokyo, Ochanomizu Women’s
University and Waseda University, among others.
She has traveled to 80 countries and lived London, Seoul, Kuwait andPeking. She was an Associate Professor of Tohoku-Gakuin University. She
has visited and co-operated with local people (especially women) in
mangrove areas of Ecuador, Vietnam and Myanmar (Burma). She loves
adventure as well as flower arrangement.

(Received 4 March 2013, Accepted 20 July 2013)