Ep.13 Plant Identifying w/ Scientific Names - Stuart Williams (@stuartwilliams_)

You're on the plants grow here podcast. I'm Daniel Fuller. Come along with me as we enter a hidden world of deep horticultural, ecological and landscape gardening knowledge with featured experts, industry professionals, and enthusiasts. This episode is about identifying plants using scientific names. And our guest is Stuart Williams, who's a friend of mine on Twitter that posts some awesome exotic and native plants. He's also a landscape architect, and a horticulturist. Welcome to the show, Stuart.
Good. Daniel, how are you?
Yeah, not too shabby. Thank you very much. So what is the natural classification system? And what's so good about it?
Well, I'll start by saying that the classification of plants is tricky is taxonomies constantly evolving. There's always new scientific research methods that challenge previous assumptions. There's estimated to be over 8 million organisms on Earth, so we need some sort of classification system to work out what's what. In biology, taxonomy is a way of grouping organisms with shared characteristics. Classification of plants goes back to ancient times the current system of taxonomies, largely based on work by Swedish botanist Carl Linnaeus, published in 1735. Since then, taxonomies progressed with new scientific methods. These enable classification based on evolutionary relationships between organisms, and descend from a common ancestor. I'll give you a couple of examples of how grouping related plants is useful for horticulture. The first example is the fungal plant pathogen Myrtle rust is a relatively new disease in Australia. And it's a serious threat to native plants, in effects plants in the metal family matese, which is useful to understand in terms of which plants are potentially at risk. More than 40 plant generating this family have been affected by this disease, including species of eucalyptus Calista men and Xinjian, which the the lily Billy's. That's one example. A second example is understanding plant cultivation requirements in the family party I see. There's 27 genera, which are pretty odd roots, which form clusters of closely spaced lateral rootlets, which add adaption for low nutrient soles. If we cultivate species in this family, we know that they are getting generally need slow release, low phosphorus fertilizer, and also need minimal root disturbance. The classification of plants is very much on the related organisms basis is very useful in cultivation requirements for plants.
So when we're talking about plant scientific names, we're really talking about evolutionarily in ages, as you said,
Yes, Yes, we are. That's where we are where taxonomists of going. Traditional taxonomy was based more on common characteristics, but because there's been new research done on DNA, etc, molecular level, they're looking at more of a common ancestor approach. So that's like plants themselves, taxonomy has evolved. Now, if you look at the different layers of classification in biological classification, taxonomic rank is the level of a group of organisms ordered in a hierarchy. There are different versions of this hierarchy, you need to be aware that different sources use different hierarchies. I'll go through one here that's used by the website. Our naturalist, as this resource can readily be used to help identify plants and I'll explain that later. Firstly, at the top of this hierarchy is kingdom. Examples of kingdoms animals, fungi, lichen, kelp, diatoms and allies, there's few others and then you have plants which also known as plant a in 2016, there are estimated to be 374,000 species of plants. So there's a lot of plants so really need a classification system to sort out what's what the next level down is phylum. And this level includes on what's mosses. And then there's this whole stack of allergies. There's clarified algae, green algae, liquefied algae and red algae. And then in another group is vascular plants, also known as trackier fighter in 2016, the rest of medic to be about 308,000 species of vascular plants. They serve vascular tissues that distribute water and nutrients within the plant. And vascular plants are themselves divided into a number of classes. And when you get down to this level, there'll be things that are a little bit more recognizable as long as some that add. First up at the cycads. We've got native cycads in Australia and they're also sometimes used in cultivation often seen the Botanic Gardens. Next is the kinkos. These are extinct except for one's very special species gingko biloba, the maidenhair tree from China, which we also come across in calibration, then there's the nephites don't know much about those. Then there's the mica pods. And the liker pods include club muscles, we've got those in Australia, so that's relevant. And then we've got conifers, including pines, cypresses, and furs. And then we've got the ferns. So these are important groups to classify your plants into. And also within vascular plants. We've got a very important group, which is the angiosperms or flowering plants, which a lot of is still within horticulture. In 2016, they're estimated to be about 295,000 species of flowering plants. So flowering plants for the vast majority of the vascular plants. And again, you're dealing with very big numbers. So that's why classification is so important. Traditionally, flowering plants divided into two subgroups that are useful for identification. The first is the monocots. These are the grasses and grass like flowering plants. And the other is the die cots. And now we'll go down to the next level which is order. And then below that is the level known as family, families of plants. Now an example of a family is probably AC, which probably includes plants from the southern hemisphere. Plant genera from this family include Protea known in South Africa is sugar pushes where they're from, and also bankss and grevilleas, which are mostly from Australia. The next level down is genus and then species, both of which are used in binomial permaculture.
Cool what is meant by binomial nomenclature,
it's a two term naming system used to name all species of living things, all the species in those, all the kingdoms that we mentioned at the start, every species name is comprised of the genus name which has the initial letter in uppercase, followed by a specific epithet which is written in all lowercase. An example of this is the swamp gum, which has the botanical name, Eucalyptus obata, said Eucalyptus with a capital A and the Avada with a small O. Eucalyptus is the genus. The group of plants that are belongs to commonly known as gum trees, which comprises more than 700 species. ovata is the specific epithet which refers to the overall shape of the leaves of this particular species.
And what's the abbreviation that sometimes you see at the end of a botanical name?
Well, let's call an author citation. And that's the method of citing the body bottom list or botanists who published the botanical name. So as an example, you have the yellow gum that's Eucalyptus look oxacillin and publishes Eucalyptus like oxygen meal, where m u E double l full stop is added to the end of the botanical name. It's a standard abbreviation for Ferdinand von Bulow, who was the Victorian Government botanist, between 1853 and 1996. Mila formally described the species and published it in 1855.
That's very interesting. So what are some plants so to get that abbreviation of the name and some don't,
all plants get the abbreviation it's just that it's you often see it without the abbreviation. But in scientific papers and a lot of scientific literature, the author citation is given so that the name can be attributed to a specific author. It's a method of citation. But you're right, you often don't see it in say, books on plants, you know, for gardens or whatever. But if you get into botany sites and scientific literature relating to plants, you'll often see it as a way of properly citing the name, or species do have that author citation after after the name.
Okay, so probably a lot of the books that I've been reading just I probably had a lower level of depth, because I'm probably working on a horticultural level as opposed to a taxonomical level or maybe even a botanical level.
It's not needed most times and most time you don't, don't deal with it. But it's just something to be aware of that if you're reading scientific papers, that's what that name relates to in its proper citation in that field. But it's something you don't have to worry about in day to day horticulture.
And what about SP dot and SP p dot? What do they mean?
The sort of more accepted version for subspecies is su Be SP dot that subspecies
What did I say?
Well, it there's two actually, I think you had SSP dot. That's a subspecies, right. And then
the SSP or SPP,
and it's very confusing because there's there's both of them. terms. The SPP is a shorthand for species. It's a plural, plural. We've got multiple species. So SPP is multiple species, where a sub species is SSP dot. But because there's that confusion, this is actually a good point, because that's confusion. The current format, more accepted format for subspecies is to spell out su B. SP. Dot,
that does make a lot more sense to roll it out that way, seeing as so similar.
Yeah, yeah, it causes a lot of confusion. So the tendency is to write it out a little bit more fully.
And so if I, if I've no, I've got a eucalyptus tree, but I'm not sure what species it is. I might just say Eucalyptus, SP dot, because I'm unsure. Would that be right?
Yeah, that's right. Yes. Yeah, we're unsure of the species here. That single sp.is for us a singular species. And you're saying you've got one species of eucalyptus, you're not sure which one it is status, put Eucalyptus is P dot.
I love that one. That's a good one I like to use all the time.
Yes, I use that quite often myself. Very well to identify.
So how to taxonomists come up with the names for plants?
Well, there are many different methods that taxonomists use for this. Firstly, they use names that come from Latin and classical Greek words to describe plants, for example, Eucalyptus that we're just talking about is derived from the classical Greek words, a U, U, meaning well, and clip though meaning covered, and that refers to the periculum, what bad cap that covers the flower bed. So it's saying that the flower bed before it opens into the flower with the statements. It's got the Bub bed cap on top and set. And so that's indicating it's well covered by this cap, enclosed by it. So that's relating back to the classical Greek words. There's other methods used though for naming there's names of people. So for example, banks here is named after Joseph banks, who with Daniel salon slander, collected the first scientific specimens from Botany Bay in 1770. Another way of naming plants is named after names of places. An example of that is, you click this cubby and answers, and that was named because this specimens of those were recently collected at Caribbean in New South Wales. And then there's other sources of names, including anagrams pans, and even jokes, which has been used as sources for names. So an example of a name based on an anagram is a genus from South Africa, called pod ranier. That's actually an anagram of the closely related Australian genus, Panda Ria. And then there's even joke names. There's a species, there's a new species of rhinoceros beetle, which was given the name cyclo Cipolla, not another one. A very bad
Not another one. Yes, in one word, or in multiple words,
that's, that's in one word, one word, not another one. So you can see it goes from the very formal sort of classical Greek and Latin to just made up stuff. So there's the whole gamut there.
And what languages are using scientific names?
What are their Latin grammatical forms a year's names can be based on other words from other lengths on words, I should say from other languages. Mostly, they're derived from Latin and Greek classical words. However, and here's a couple of examples for of epithets in species names. So species name example, sexy Cola, that's derived from the Latin word meaning, or words meaning rock dwelling. And an example of that is thrip. The main sex of cola which is the rock group, the main, which is often found on granite outcrops in Western Australia, the second band is trapped around which is derived from the classical Greek words for for wind. And that name is used on Eucalyptus trapped era, which is known as the four wing Meli in the southwest of Western Australia.
Cool, so there can be it's really just pretty loose, then it's not necessarily ironclad, as long as you stick to the other binomial rules.
Yeah, there are there are strict grammatical rules, but you can derive view around the base words from anywhere, and people name them after even after things named after Steve Irwin, Steve o and I type type epithets so yeah, the words can come from anywhere but the grammar grammatical form is too Killer formula. And then that gets on to the next part that there are grammatical rules. And these are really quite complex. They sit out in the international code of nomenclature for elkie, funghi, and plants. And that code is based on decisions of the making, the main culture was by problems, but its network section on the technical Congress IBC, which is held every six years. And the current version of that code is referred to as the shenzen code, as the last Congress was held in Chin's shins in in China in 2018. And that code is on the internet. But if you're not involved in naming plants, then you don't have to write too much about that.
And we've talked a little bit about the word epithet that sort of been thrown around a little bit, can you describe what that word means in a little bit of detail for us?
It's basically the second word of the botanical name. So the first one, say, Eucalyptus, that's the genus name. And then, if it's Eucalyptus or vitae ovata is the specific epithet, which is just the specific name given to that species. So obata is the specific epithet. And Eucalyptus is the genus and you put the two together to give you give you the binomial name.
So what's the difference between a species and subspecies?
The subspecies is just the next level down a subspecies is a group within a species which is branched off. It's got slightly different characteristics, which are mostly due to geographic isolation. So they're related, but then you might have one that's over the other side of a mountain that's developed a little bit separately, not separately, enough to be a separate species, but just a little bit different.
And how about a variety
varieties the next step down the subspecies, the one that you need to be mostly aware of formally, Friday is the next step down sets finer detail, and then you've even got a rank below that form, which is even finer detail. Again, you don't have to get to write about those other than just be aware that they exist as, as as names, but in terms of form or publication of botanical names. You're mostly concerned with down to species and subspecies level. And the rest is is fine a detail.
And then we have another thing called the cultivars. Can you tell us a bit about what that is, and what's different from a variety?
Right now we're getting into horticulture. So we're leaving the, the formal botany but we have varieties that are developed for horticulture and agriculture etc. So a color bar is a cultivated plant for it selected for desirable characteristics. So an example of that is the Hass avocado which you find in your local supermarket. Its full name is persea. Americana, Hess. With the color, hair color by name has written with a capital H in enclosed enclosed in single quotes. So single quote, capital H, AWS, and then end with a single quote. And that particular code was originally a seedling grown by Rudolph Hess in California in 1926. And all avocado trees with this name agenda clients of this original tree grafted onto a root stock. So the idea behind cultivars is that they're consistent, completely genetic clones in general, that they're consistent in the propagation. Another example is gerbil Leah Robin Gordon, which is a shrub that's familiar to many gardeners in Australia and that originated as a seedling in the garden of David Gordon in Queensland who named after his daughter. And he saw that it had prolific and sustained flowering and it's a hybrid of grevillea Bank side from eastern Australia and grevillea by peanut if it up from Western Australia, and that was commercially released in 1969. And the plants for that are propagated by cuttings so that they are genetically identical to the original plant. So if you go to a plant nursery or Bunnings, or wherever and and buy a gorilla Robin Gordon, it's going to be exactly the same plant with exactly the same characteristics as what David Gordon had in these garden in Queensland in 1969. So the idea of cultivars control over the exact type of plan, because if you've got species say species grown from seeds, say Eucalyptus you can get a lot of variation in seedlings. With the height of the tree, they can The sun might develop with a crooked trunk, but some might be taller and straighter. There's quite a bit of bad genetic diversity. But most cultivars are clones, and they're identical. So the idea is to produce a plant and market it and know exactly what you're getting.
And I guess when we say clone, or, you know, a seedling, a seedling comes from two parents. So you've got the Poland and the egg, whereas you only got a clone that might just be it's not as scary as it sounds. I mean, it's not done in the lab, is it?
No, it can't be done in the lab. But generally not you can just nip a bit off here, Robin sticker cutting in a pot. And if that gets roots, that'll be a clone of the other plant that you took the cutting off. So it can be as simple as that, or it could be done in the laboratory with tissue culture, etc. Yeah, no, it's not not scary at all. It's it's just a way of saying that the plant is john genetically identical.
So what are trade designations and selling names?
Well, they are plant names that are trademarked, or they may be names used for plants that are registered for plant breeders rights by an authority such as IP Australia, they're used because all of our names are in the public domain. An example of this is one in Australia is really a cherry cluster. In this case, it also has the obscure cultivar name of Tw, the one primarily because they want to market this and get the the royalties from from the plant known as gorilla cherry cluster. And then another example is the rose Friday iceberg. This is a selling name for the cultivar called Corbin. Now that's not something you'll find in a nursery. That's just the name. So you've got the reference to what it is, but, but we all know about iceberg roses. And that's the name you'll see in the nursery. But that's actually a trade name rather than the color bar name. And then, in marketing, they might use selling names in different regions of the world. So for instance, with the iceberg rose in other parts of the world, it might be marked as it's marked under these other names fade in age and, and another one, Steve Bichon.
How do we go about correctly identifying a plant that we find out in the field? Do you recommend a plant identification app or maybe even a plant key? Or do you use both?
Yes, I do use both I use everything that's available. When we look at a plant we need to look at its various physical characteristics such as flowers, stems, leaves, and fruits. This requires some knowledge about neat and familiarization. With botanical terms, for Australian plants and plants naturalized in Australia, I tend to use the herbarium websites for the relevant states. So I'm in Victoria. So for Victorian plants, I'll use it the big flora, that's a website hosted by the Royal Botanic Gardens in Pretoria. And it gives a description of each species, together with photos and herbarium specimen specimen images. And, and that has a key to species found in Pretoria, and Ks are the gold standard for planet identification. But they do require a knowledge of botany. And you need to look at minute detail, which might require using a hand lens to really see some quite detail, small features. And you also need to get measurements of the plants. And that would require either measurements of the plants in the field, for instance, for National Park, because you can't go about picking things from national parks. Or if you're on private land, and you're working for someone, you might bring back specimens to your home or office as long as they're not particularly native flora. A tool I'm increasingly used to help with plant identification is the website of nearby naturalist. And that's an online database of observations of biodiversity. And it's got 1 million registered users around the world, including scientists and citizen scientists. And that mostly deals with wild growing plants and includes native and naturalized exotic plants, but also includes to a lesser extent, some commonly cultivated plants. Plant observations are in the form of photos and with the georeference that can be uploaded to the site. And then suggestions for the ID are given by the app. And then other members of the community can come in and suggest an ID or make a comment. So you've got both the sort of and I don't quite know how to do it, but it's kind of like machine learning and then and also based on based on geographic location, you know, the likelihood of something being in an area, but if that fails, and it can certainly can fail Then you've also got opportunities for other people on that side who can suggest ideas for you. And you can and can put comments within the side. So that sort of works on multiple levels. So I find that quite useful for actually just browsing and looking at what species are commonly found in a certain area. For example, if you come across what looks like a member of the PAC family, in the Grampians National Park in Victoria, you can enter the family name, pro Pac, and then the location Grampians National Park. And then we'll come up with all the observations of THC within that park. And you can look through all the photos and you can find a match, you know, just visually looking for all the photos that might match your particular plan. If you suspect it's in that Protea family.
Awesome. And can you just go a little bit about how a plant key works for our listeners?
A plant key? It's a sequence of sort of questions and answers that you go through, and it goes through the various ranks of plants. And then when you get down to genus level, it gives you within the genus, a list of species, and then you go through one by one. And it's kind of either yes or no. And if it's Yes, you go to the next one, and then you go on to the next one. So it's a sequential way of coming up with plant ID, but you do have to have the technical knowledge, and you do have to have sometimes very fine data second, can be pretty tricky. Some of its more straightforward. Some of its really, really hard to discern. And sometimes you find some of the keys may not be written as clearly as you might like. So it's a bit tricky sometimes. But that is the gold standard. And that's what botanists work with case to actually come up with a definite determination of plant ID but it's, as you sort of develop your knowledge of plants you and get an eye for what family a plant might be in getting sort of develop a visual sense of what family of plants see and then perhaps watching this and, and go that way. But yeah, the the the keys The is the gives you a definitive answer.
And there are some apps out there where you just take a photo, I found that those apps can be hit and miss I think they're probably a pretty good place to start, but I probably wouldn't trust them. 100%
Yeah, yeah. No, I'm, I'm a bit wary of them. I mean, that they're getting better all the time. And and they've got to be fed has got to be taken on the right angle in the right light and be in the database. I also find it's, I mean, I've tried a few of them. And I sort of give up after the first really bad answer that they give this guy or this is not gonna be any good. But I think they have a role. And you're right, as a beginner, this is very apt on I can't remember lots of the muffin top of
my head. Yeah, this brilliant identification app or something, something, something like that. I'll have a link in the show notes for our listeners.
Yeah, there's quite a, there's quite a range of them. But I find for myself, they're not developed far enough for my use. And I find that they're not developed Well, for Australian plants. Something to look out for in the future. I think but but certainly for beginners yet yet. Give it a give it a go. But you've got to know, the thing is, if it comes up with the wrong answer, how you're going to know it's the wrong answer. Yeah. And it will come up with the wrong answer. So
I mean, you know, you have a toolbox of different ways of identifying plants, and you got to use all of the tools, you got to use websites, you got to use books, you go through photos on social media that people have put up and other photos on Google Images, you use the whole lot and use those statehood herbaria website from the very states if you're in Australia,
and I naturalist as well.
And I'd actress as well. So use everything, there isn't one, one solution that'll that'll do it all you've got to be prepared. If it's a really difficult ID to look at multiple sources. But the main message really is just to look at these multiple sources and and you really have to just develop a visual sense over time. It is difficult when you're starting out but you get it over time.
So in your opinion, who do you think would benefit from starting the journey of learning plant scientific names? Is that for everybody? Or maybe just a few people?
Well, it's for everyone who deals with plants in their everyday lives, which is a lot of people and you know, that can be home gardeners, professionals. They're all going to benefit from having Some knowledge of plant scientific names. In fact, most people probably already recognize many names for instance, Camelia Magnolia Rhododendron and, and Aloe Vera. So people got a starting base that they'll probably know a lot of names to start with. So it's not as difficult as you may think. And it's not as foreign to people as they may think. Certainly, there's some clanger names out there in the scientific world, but a lot of them are pretty straightforward.
And some of those common names as well can be two different plants, or even more different plants might actually have the same common name. So we might run into problems. And let's we do learn those scientific names.
Yeah, that's very much the case. For instance, there's about 20 species in Australia, our vehicle lips, which are known as red gums. So if I just say red gum, well, in Melbourne, I'll probably think Eucalyptus camaldulensis remover, red gum, but around Australia, there's 20 different species, known in local areas as red gums. And that's where it gets tricky. As soon as you get out of your local area is common names are going to be applied for different plants. And you go to a different state, you've got Eucalyptus vatta, before we're talking about before, which in Detroit is a swamp gum, and in Tasmania, that's the black. And then you've got other ones like Eucalyptus luxilon, which is yellow gum in Victoria, and it's now I forget which way around that is, I think it's a year, and blue gum in South Australia. So common names are very well, the big problem is the ambiguity, you just can't be sure of what you're getting. And if you're, you know, ordering a dozen red gums from a nursery, you really want to give them that scientific name to make sure you're getting exactly the right mind. So it's very important for people working day to day with plants and, you know, buying plants at nurseries and, and gardeners etc. You know, don't have to be a total expert, but just having a knowledge of the basic names of plants that you're dealing with is certainly useful. And the other thing is, if you're using scientific names, you've always got genus and species name included in it. And having the genus name just makes you more aware of the grouping that a plant is in, you know, Eucalyptus, Avada. And then you're aware that with Eucalyptus, Avada, it's in the genus Eucalyptus, and that's a genus of 700 species. If you go to California, they say, Oh, we hate Eucalyptus, you know, they're terrible trees and, and then you realize they're talking about the blue gums, Eucalyptus, globulus, which they've had it there for years. And that's just one species of 700 species. That's where you sort of need to be careful with your scientific names, to use the whole, the complete binomial, Eucalyptus globulus, not just you clips, to represent a particular species. It stops misunderstanding, which is always a good thing, because you get yourself into trouble with misunderstandings.
So what are some of your personal favorite Ozzie families in general,
I have to say my personal favorite plant family is the protease See, but that's, there's lots of species in Australia. That's not just Australia. No, it's mostly is southern hemisphere, plant fat family, and that's got iconic species like the New South Wales, Rota, tilapia, spcs. Systema, and then there's the bank C's and really is. And those two generar they spill out to some of our neighboring countries such as Papa New Guinea, Indonesia and New Caledonia. And within that, I think gorillas have been my favorite genus. And there's more than 360 species of those, and only six of those species are outside Australia. So the vast majority found within Australia. And I think one of the factors that got me interested in in that genus was bushwalking. And that in my state, Victoria, they were associated with scenic areas and some very high peaks. There's guerrilla Victoria at Mount Buffalo, really a micro stage here at Mount Castle in the Grampians. And there's gulia. Monster Karna at like mountain. In Victoria, it seems like every mountain has got its own grevillea I'm not so interesting climbing the mountains as finding the girl is and also they can range from groundcovers just prostrate plants low to the ground, or they can range right up to the silky yolk which is a full on large tree.
I thought that was a corner for the first time I
saw that one. All right,
until you understand that
they start off with a bit of a conical shape. But then when they get a hold, they get a bit scraggly in their shape.
Yeah, that beautiful family. Yeah, I definitely agree with that. That's a great choice.
Yeah, and great diversity within Australia and traveling around Western Australia. Last year in the year before, great diversity of species in the southwest there which are of great interest to people interested in plants.
Is there something else that you'd like our listeners to know about? Just before we wrap the episode up,
I think just to say that classification and naming of plants is constantly being revised, you just need to be aware of that bit of a pain. But it's, it's always a work in progress. So things change over time. So you've also got to know that if you've got your textbook, on various plants, you know, slightly to be out of date already. So it's a good idea to check botanical names against databases, if you want to make sure that you're using the correct botanical names, this Australian plant index. That is that the API hosted by the Australian National Botanic Garden in Canberra. And that's an online database of all published names of Australian vesicle plants, that is linked to the Australian plant census. And that's always a good resource to check if names are correct and up to date. And then in terms of a global plant database, there's quite a few to choose from, but I tend to mostly like mostly use a website called g ri in green global. And that's an online database hosted by the United States Department of Agriculture. And that gives you scientific names, common names, distribution, and economic use of plants. So that's useful if you're looking at plants. Oh, it has Australian plates as well, but looking at plant species from all parts of the world.
Thanks so much for coming on, Stuart. That was awesome. And I hope our listeners have learned a lot more about plants scientific names, what they used for and how to actually end up using them.
Well, thank you very much, Daniel.
I hope you've learned a lot about using plant scientific names for identification. This is quite a dense subject. So if you're new to plant identification, I definitely do recommend having another listen to this episode in a couple of weeks. In the shownotes, you'll also see some links to some of the material that I've written, including one article on plant scientific names, and another one on using flowers and leaves to make an identification. I've also got a blog series on some of the most common 25 families, sub families in general that I've seen in Ozzie gardens. There'll also be a few other links to some of the subjects that we've talked about, such as plant identification apps, and I naturalist as well as the Vig floorplan key

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