Annotations of the seaweed geographical distribution in the Atlantic Ocean North of Equator, in the Mediterranean and in the Baltic
by FREDRIK RUTGER AULIN
translated by Algologia


[CHAPTER 3. THE GEOGRAPHICAL DISTRIBUTION OF ALGAL ORDERS, GENERA AND SPECIES.]

Order 1. Corallinales [as Corallineae]

The plants that belong here represent a rather rich group of highly specialised algae both as regards structure and reproduction. Members of Corallinales occur in almost all oceans, although they are more common in tropical and warm waters. Some species reach very long to the north and the south; they generally thrive well on both sides of the Equator, but it seems that they occur in larger amounts on the Pacific rather than the Atlantic coasts; apparently many and well-developed species of this group are found in Australia. The Corallinales thrive on very different depths; one founds them from near the splash zone and down to, as previously noted, relatively significant depth. The individuals that grow in shallow water are usually fertile, while those that are brought up from the depths are generally sterile, although their vegetative structures are apparently well-developed. The species of an order that occur in so far remote areas and in so different depths, as the Corallinales, must of course show a great diversity; moreover, one often encounters individuals of the same species that because of the different conditions have changed form; the species that belong here are found partly on wood, stones, and similar substrata, and partly on other algae. About 150 species are described; close to 1/3 of them is found within the here examined regions (i.e. Atlantic north of Equator, the Mediterranean and the Baltic). Most of them occur in the warmer parts of the Atlantic, in the Mediterranean and the Adriatic, and become less and less towards the north, so that on the Scandinavian west coast only a few species are known. Among the genera that belong here, one can name Corallina that has a few species in the different parts of the [here examined] regions, and also in Scandinavia; C. officinalis (L.) occurs throughout the entire [examined] area and as far north as the Arctic Ocean; most species of the genus occur in the Southern Hemisphere; Amphiroa that occurs up to the 40 latitude on both sides of the Equator, has in the Mediterranean a couple of species, one of which even occurs in North America[Footnote 7]; therefore, it is strange that not even a single species of this genus is found on the European Atlantic coast; besides, the genus has many species in the Indian and Pacific Oceans. Jania has a single species in our [Swedish] coast, a couple in North America and in the Mediterranean, as far south as South Africa, and also several other species from more remote areas. Hapalidium [Pneophyllum ?] is a strange genus with just a couple of species in the Mediterranean and the Adriatic. The genus Melobesia, mainly distributed in the temperate seas, has apparently many species, whose number decreases towards the Poles; our knowledge of the North American species is limited; in the Mediterranean and the Adriatic, the genus is well represented; M. membranacea (Esp.) - common in nearly all waters- exists on our coast together with some other here belonging species. Lithothamnion has several species within the [here examined] regions, mainly in the temperate parts; even on our coasts occur a couple of species [of that genus]. (Some other genera are restricted to the Southern Hemisphere.)

Order 2. Floridales [as Florideae]

Family 1. Rhodomelaceae. This family is the largest and most important amongst the red algae, not only in the Atlantic but also in other oceans. The various members of this family are encountered partly in the warm and temperate seas, and partly in the cold ones; some of the species are cosmopolitan. Within the regions [here examined], the relevant members occur not only in the Mediterranean and the Adriatic but also in the cold and warm parts of the Atlantic, not just in Europe but also on the North American coast; in the North Sea and its bays, several species are found, and even in the Baltic occur a few. More than 300 species are described, of which about the half is found with the different regions [here examined]. As an example of the here belonging genera, that exist in the warmer seas, we can name Chondriopsis, Acanthophora, Bostrychia, Vidalia, etc. which occur in large number both north and south of the Equator; these genera have species in the Mediterranean and Adriatic Seas and in the West Indies; one or another extents its distribution to the U.S., to France and England. These, like similar species of this group, are rather restricted to bays than to the open coast; something peculiar for Bostrychia, is that some of its species are found in brackish and even in fresh water. Here also belong some poor in species genera as Alsidium, Digenea, etc. which have about the same distribution as mentioned above. Amongst the genera whose most species are found in the Southern Hemisphere, and one or another in our regions, we can name Martensia, Amansia, Dictyurus, etc. that are encountered in the Mediterranean, the Mexican Gulf or in West Indies. Within this family is found the previously mentioned relationship between the algal vegetations of the Mediterranean and the West Indies, [visually] that some algae are restricted to just these two regions. Rhodomela and Odonthalia are arctic genera; the former has its natural habitat in the Southern Hemisphere; on the other hand, almost all species of the latter genus occur in the north, most of them in the Okhotsk and Kamchatka Seas. Rhodomela has a few species - R. subfusca (Woodw.) is found up to the Baltic - while Odonthalia has one species that extends between the northernmost Atlantic and England reaching also the Oeresund. The largest and most significant genera are Polysiphonia and Dasya, whose species represent more than half of the entire family. Polysiphonia, which is the most rich in species genus, occurs in all coasts, even in the northernmost ones - on the coast of Finnmark still occurs P. urceolata (Dillw.), etc.; in the Mediterranean and Adriatic Seas, species of Polysiphonia are rather common and many are characteristic for these seas; at Cadiz, the Canaries and even the West Indies, they occur in large amounts; moreover they are common along the European coast right up to the North Sea and the Baltic, as well as in the U.S. The species differ considerably as regards size; they also occur in very different depths. The genus Dasya has many species both in the Northern and Southern Hemispheres, from the Equator and towards the Poles. Amongst those occurring within the [examined] regions, several species are characteristic for the Adriatic and Mediterranean Seas. Along the American coast numerous species are found; on the European Atlantic coast, many are encountered, amongst which D. coccinea (Huds.) [Heterosiphonia plumosa] is one of the most beautiful algae on the coast of Bohus [Swedish west coast] (the Family has numerous genera that are restricted to the Southern Hemisphere).
Family 2. Laurenciaceae. Species of this family occur in one or another form in almost all seas except the Arctic; they are not so many and belong mainly to the warmer seas of both hemispheres, but have also a few species on our coasts. Of the genus Laurencia, we encounter species from the Mediterranean and Tangier up to the Faeroes and the Bohus, as well as outside the examined regions; just a couple of species occur in North America. Laurencia is the most rich in species genus within the family; its species thrive in the warm seas, [such as] the Mediterranean and the Mexican Gulf and also in many sites in the Southern Hemisphere; in Central America, we find a few species; more in the north, the species number diminishes; a similar condition exists on the European coast; in west Scandinavia we encounter a couple of species. Finally, the genus Bonnemaisonia must be cited, whose single particularly beautiful species exists also on our west coasts; it seems to be restricted to Europe. Not a single species belonging to the Laurenciaceae occurs in the Baltic. (To this group also belong a few genera from the Southern Hemisphere.)
Family 3. Sphaerococcaceae [as Sphaerococcoideae] comprise numerous species, that belong to the warmer seas; a few exist in the temperate and cold waters. They have their main distribution in the Southern Hemisphere, where the numerous genera have developed many endemic species at the Cape of Good Hope and in New Holland. The largest part of this group, within the [here examined] regions, is encountered on the south coast of Europe and the south part of North America, in North Africa, in the Mediterranean and the Adriatic Seas; yet, some species still exist in the North Scandinavia and Greenland; in the same way, we find one or another species in the Southern Hemisphere far in the south. We know about 150 species, one third of which are encountered in the here examined regions. On the west coast of Scandinavia, we find some and in the southernmost Baltic another few species. A rich in species genus in this group is Gracilaria, that has representatives from the tropics to the North Sea; most species of the genus in the Northern Hemisphere are found in the West Indian Islands, in the Gulf of Mexico, in the Mediterranean and in the Adriatic Seas. Gracilaria confervoides (L.) is distributed from the Equator to high latitudes both in the south and in the north, G. multipartita (Clem.) has also wide distribution but not as much as the previous species. Another genus, Nitophyllum has many recently found species in the Southern Hemisphere; some species have been long known and to exist in abundance from the Atlantic coast of Europe to England and Norway, from Africa and the Mediterranean. On the North American coast, a very different situation exists, just a few specimens belonging to 2 species have been found; although species are found in Tangier, Cadiz and the Mediterranean, we have not encountered any in the West Indian Islands, as it would be anticipated. Delesseria is one in many respects significant genus, that particularly inhabits the colder waters of both the Northern and Southern Hemispheres; one or more species are found in both; certain species in the north correspond to some in the south; some have a very restricted geographical distribution, other are widespread; the southernmost locality in the Northern Hemisphere is Tangier. Most species of the genus exist in the Pacific and the Arctic Oceans. Sphaerococcus has a few species in the Atlantic. Two genera with just few species occur in the Mediterranean and the Adriatic Seas. The genus Euchema [that occurs] in the East Indies, the Cape of Good Hope and in New Holland, has a couple of species in West Indies; moreover a few poor in species genera exist in the warmer part of the Atlantic. (It is natural to find many genera of this family outside the examined regions.).
Family 4. Gelidiaceae have most of their species in the warmer seas, within which some have a very widespread distribution. The family does not include many species, but these occur in all parts of the world; most of the species exist in the Southern Hemisphere, while just a few in the Northern Hemisphere. On the European coast just two are known with certainty, both in the Atlantic; one of them is also found in the Mediterranean (whether any other species of the family occurs there it is not known for sure); from the Central America, several species are known; on our coasts until now only one species is found, and this only from the SW Norway. Gelidium, which is the main genus, has species in the Indian Ocean and in the warmer parts of the Atlantic and the Pacific Oceans; two [species] reach England and Scotland, and G. corneum (Huds.) is also found on the Norwegian coast. (A few here belonging genera, of which one has a species in Brazil, exist in the Cape of Good Hope and in New Zealand.)
Family 5. Spongiocarpaceae [as Spongiocarpeae] is a small insignificant group, whose genus Polyides has one species occurring both on the European and North American Atlantic coast.
Family 6. Squamariaceae are represented by a few small in size, easily overlooked plants, and therefore they are little known - Harvey describes, probably because of this reason, just two species from North America - and therefore it is rather difficult to give an account of their distribution. All have, of what is known, an insignificant distribution, each of them within its region. Most of the species are known on the European coasts, that are the best investigated; they have representatives through Skagerrack and Kattegatt as far as in the Baltic; a few species exist in the Mediterranean and its bays. The most important genera are Hildenbrandia and Peyssonnelia, of which the former has its species mainly distributed in the Atlantic as well as in the Mediterranean and the Adriatic, and even one species in fresh water; the latter genus, apart from some species in the examined regions, has even one or another little known species in South Africa. Actinococcus [the carpo-tetrasporophytic stage of Coccotylus] has two species in the Baltic; moreover, there are some other insignificant genera from different parts of the examined regions, such as Petrocelis, Cruoria, and other; of the last named genus there is a species even in our west coasts.
Family 7. Helminthocladiaceae [as Helminthocladieae]. This relatively poor in species group mainly belongs to the temperate and warmer waters; the northernmost sites we have found members of it are in England and the North Sea, and even in the SW Baltic. Most of the known species are encountered in the here examined regions. Numerous species are found in the Mediterranean and in the West Indies, and a few on the Scandinavian coasts. Helminthocladia exclusively belongs the old world, where 2 species of the genus are found. Nemalion has also a couple of species on the European coast; Nemalion multifidum (Web. et Mohr) occurs both in Europe and America. The richest in species genus is Liagora, whose most members occur in the warmer seas; in the examined regions, some species are encountered in the West Indies, a few in the Mediterranean and some are cited by Harvey from North America. Moreover, a few minor genera such as Helminthora and Scinaia are also found in the examined regions. In this, like in the previous family, we also encounter species that even grow in fresh water.
Family 8. Hypneaceae occur exclusively within warmer seas and do not have a single species that extends to the north further than to France. Only a few genera exist, and their species are largely met with in the Southern Hemisphere. Almost all species in the area here considered are found in the West Indies or in the Mediterranean. The main genus is Hypnea, whose most species are found in the Indian Ocean, at the Cape of Good Hope, and elsewhere; a few exist in the here examined regions. Hypnea musciformis (Wulf.) is widespread in tropical and subtropical seas.
Family 9. Wrangeliaceae comprise just a few poor in species genera, whose members are found in the warmer seas; a few are met with in the Southern Hemisphere. Wrangelia has 3 species within the examined regions; one of them extends as far as to Ireland. Naccaria appears to be a European genus, whose species are spread; one grows even in England and Heligoland. Here also belongs Spermothamnion, whose species S. turneri Mert. reaches Oeresund [in the Baltic].
Family 10. Rhodymeniaceae belong, with few exceptions, to the cold sometimes temperate seas, not only in the Northern but also in the Southern Hemisphere; however, one or another [species] occurs in the tropics. The relevant genera are not rich in species; about half of the number of species is encountered within the examined regions. Therefore, as one excepts of what was said, the family is poorly represented in the Mediterranean; in Central America, there is none. Along the North American and the North European coasts, many different species occur; none of them, however, extends into the Baltic, although some reach the Scandinavian west coast. The genus Rhodymenia has 3 species in the North Atlantic, and other species are found in Peru, Indian Ocean and elsewhere. Euthora has 2 species, one in the northernmost Atlantic and the other from van Diemens land ! [Tasmania] The genus Rhodopyllis, with one species in Scandinavia, belongs also to the northern Atlantic, but has a single species as far south as Cadiz and the Mediterranean. Similarly, the beautiful genus Wormskioldia [Delesseria] has its centre of distribution in the northern Atlantic and extends until Skagerrack. The most rich in species genus is Plocamium, although within the examined regions it is represented only by one species P. coccineum (Huds.) with very large distribution within both hemispheres, in the northern one from Faeroes and Scandinavia to the Canaries; the other species of the genus belong to the Southern Hemisphere, where they are spread in the Pacific, Atlantic and Indian Oceans.
Family 11. Cryptonemiaceae comprise two groups well-separated from each other on the basis of their reproductive structures; since they even have different geographical distributions, they are here considered separately:
1. [Tribe] Gigartineae. These have their centre of distribution in the Pacific Ocean; they do not belong to the warmer seas in the same extent as the Cryptonemeae. Numerous extent along the NW coast of America, other are re-encountered in the Indian Ocean, in Chile, Peru, the Cape of Good Hope and in Australia. In the Atlantic just a smaller part of the known species is found; some extent north to the Arctic Ocean; other occur in the Mediterranean, a few on the Scandinavian west coast and a couple of them enter the Baltic Sea through Oeresund. Gymnogongrus and Phyllophora that have about the same number of species in the regions here examined, are the most diverse in the whole group; a few species of the last mentioned genus extend far in the north, up to our coasts, and a few as far as Iceland; even in the Baltic we have Phyllophoreae and one, P. brodiei (Turn.), is found up to Qvarken [Bothnia Bay]; both genera occur in the Mediterranean and in the warmer parts of the Atlantic; they also occur outside the regions here examined and Gymnogongrus has most of its species in the Indian and the Pacific Oceans. Kallymenia has several species, partly within or outside the here examined regions. Gigartina has a few species in the relevant regions, but numerous in the Southern Hemisphere. Rissoella and Constantinea, that belong to the Pacific Ocean, have one species each in the Mediterranean. Numerous other genera, which like those just mentioned have their centre of distribution in other seas, have one or another species in the regions here examined, such as Chondrus, Ahnfeltia, Callophyllis, which have one species each in Scandinavia. Certain species apparently have a widespread distribution within the examined regions as also outside; thus, for example Cystoclonium purpurascens (Huds.], Gigartina mamillosa (Good. et Woodw.), Chondrus crispus (L.) och Ahnfeltia plicata (Huds.) extent from the Arctic Sea to Gibraltar and even south to Brazil on the American coast. (The genus Iridaea has more than 20 species, 6 of which occur on the NW coast of America; not one occurs in the examined regions. Moreover, several other genera exist not having a representative in the our areas.)
2. [Tribe] Cryptonemeae. The plants belonging to this group prefer the warm and the tropical seas; yet, cold and temperate species also occur here. In the Mediterranean and Adriatic Seas, as also in the adjoining regions of the Atlantic as well as in Central America, occur rather many species, while they are poorly represented in the northern Atlantic and on our coasts where [only] some species are found. They often grow in depressions, on the shore or on submerged rocks or in mud, etc., in deeper or shallow waters. A couple of species, Dumontia filiformis (Fl. Dan.) and Furcellaria fastigiata (Huds.), enter the Baltic; the last one even the Bothnia Bay. Amongst the here belonging genera, we can note Halymenia, whose most species are found in the Mediterranean, Adriatic and nearby regions in the Atlantic, from where they extend to other places - ones species [Halarachnion ?] is even found on the coast of Bohus [Swedish west coast] -; about half of these genera are characteristic [endemic] for the first named sea. Nemastoma, whose all species with one exception are found in the regions examined, thrives also well in the Mediterranean, where most species are exclusively found; a few appear also in the Atlantic and one even reaches France. Even Chrysymenia has several species characteristic for the Mediterranean and the Adriatic Seas; Harvey describes no less than 5 species from America, where they occur in deep rock depressions. Cryptonemia has several species within the regions here studied. Grateloupia and Schizymenia have each several species; the largest number of them occurs outside the examined regions, but one or another is also found within; Schizymenia edulis (Stackh.) reaches Oeresund. Here also belongs Rhizophyllis with one species R. bangii (Hornem.), originally reported from Fyen [Denmark]. Species of the genus Chylocladia are found in the Mediterranean and the Adriatic Seas, as well as in America; one species is distributed along the European and even Scandinavian coast. Rhabdonia, that in fact belongs to the Southern Hemisphere, has one species in the West Indies. Halosaccion belongs exclusively to the Arctic Sea and northern parts of the Pacific and Atlantic Oceans and one species extends to the North Sea along the Norwegian coast. (Moreover, there are several genera with species in widely disjunct areas within the Atlantic as well as in other seas.)
Family 12. Spyridiaceae comprise just a single genus, Spyridia, with a few species, that all belong to the warmer seas; within the investigated areas, there are species of this genus in the West Indies and Cadiz as also in the Mediterranean. Spyridia filamentosa (Wulf.) has widespread distribution throughout the warm seas, both in the Atlantic and Pacific Oceans, in the Mediterranean, along the European coast to England and along the North American coast to Massachusetts.
Family 13. Ceramiaceae. The species of this family that are generally rather small and delicate, are encountered in very different regions where they occur in very different depths and in waters with considerable variations in salinity. The species which belong here are generally parasites [epiphytes], occasionally are also found on lifeless substrates; [they may grow] either near the splash zone or in great depths; some thrive in marine waters, other extent in bays whose water contains just a small amount of salts. As a result of this, their distribution is rather widespread; the here belonging species are met with both in the Atlantic and the Baltic as far as the Bothnia Bay, as well as in the Mediterranean and other warmer seas. In the tropics, they do not seem to be so numerous, as in the northern seas; some characteristic [endemic] genera do not exist for the tropics; on the European coast there are more Ceramiaceae than on the American coast, probably because the North American coast neither shows the same length and variety of habitats as the European one, nor is suitable as this for these small algae's distribution, and moreover the former coast is not so well investigated as the latter one. Something else that also contributes to the difficulties of knowing many red algae, and apparently this family's geographical distribution, is that, in contrast to the brown algae, they have a loose and easily damaged structure. The fact that the relevant species are usually found to be sterile makes their study even more difficult. Finally, many species are small and are easily overlooked. Naturally, many species belong to this family, and because the opinions of the authorities differ greatly, it is difficult to estimate the number of known species; however, we could postulate that at least 200 species are known; about half of them are known in the regions investigated. The most rich in species genus is Callithamnion sensu lato; it comprises about half of the species described; here we encounter several [species] with widely diverging geographical distribution; while some are restricted to England, France, Greenland, in Skagerrack, a.s.o., other apparently have a widespread distribution, occurring not only in the Atlantic but also in other seas. From the Mediterranean and the Adriatic Seas, a large number has been described. What was said about the geographical distribution of Callithamnion, applies also to Ceramium, another large genus that has numerous species on the Scandinavian west coast as well as in the Baltic and in the Bothnia Bay. Griffithsia, that apparently prefers the warmer seas and the open coast, has most of its species in the Mediterranean and the adjoining regions in the Atlantic; some occur as far as England and even longer up to the north; one species occurs in North America and also in Scandinavia. Ptilota is again met with in the cold seas; of its species, 3 are found within the regions examined and several in the North Pacific. Ptilota plumosa (L.) is even found along the Arctic coasts. Apart of Corynospora, Halurus and Crouania, that have most of their species within the examined regions, we must name Centroceras and Dudresnaya (with one species occurring even in Bohus [Swedish west coast]) that belong to the Mediterranean, and the temperate and warmer Atlantic. (Moreover, [to the Ceramiaceae] belong several small genera, whose species occur entirely outside the examined regions.)
Family 14. Porphyraceae comprise only a few genera that are widespread throughout the examined regions. In a few areas we have encountered local species, otherwise they generally exhibit a widespread distribution. On our coasts, a few species occur partly in deep water, and partly in the splash zone in bays, one even in nearly fresh water. Porphyra and Bangia, that both have species on our west coasts, belong to this group; Bangia extends into the Baltic and in the Bothnia Bay.

The text continues in AULIN.4

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