Living Collection Virtual Herbarium: Verification Process

Acacia baeuerlenii Correa alba hepatica maxima Rosa longicuspis Rosa longicuspis   Spiraea japonica

Revisions or Floras ?:

A revision is a taxonomic treatment of a family, genus or a group of taxa. (a list of revisions can be found in Mabberley,D.J. 'The Plant-Book') It usually includes a study of the group phylogeny and try to retrace the natural evolution in this group. The revisions are very useful for naming because they treat all the taxa of a group and this worldwide. So there is no risk to miss a species because it is from a different area. Unfortunately if the group is very large, the key and species descriptions will be very long and will use many detailed characters which might be difficult to familiarize with.

A Flora is a treatment of all taxa in a given area. It is usually less detailed than a revision and the key often uses characters that are easy to familiarize with. Unfortunately it often doesn't show phylogeny or natural evolution between species so the species definition and key characters often differ according to the author.

Selection of Flora available online for the temperate areas:

Flora of North America, Flora of China, Flora of Pakistan, Flora of New Zealand, Flora of Australia, Flora Iberica, The Jepson Manual Higher Plants of California...

Selection of Flora available in libraries for the temperate areas:

Flora Europaea, Flora Graeca, Flora USSR, Flora Iranica, Stace British Flora, Flora of Japan.....

For cultivated plants without origin the European Garden Flora is the best resource. Cultivars are difficult and they can be checked with horticultural encyclopedias and the RHS(Royal Horticultural Society) databases. Some ICRA (International Cultivars Registration Authorities) should also be able to help.

Different naming methods:

To show and illustrate this part we have chosen the following Delphinium that we received for verification.

The next steps should show you several techniques to check and verify plant names:

Specimen to identify

Ideally the specimen should be in flower and fruit but also shown with roots. Of course this is rarely the case and we have to focus on the material we have, in this case a flowering stem, cauline leaves and a few basal one. Some information on the origin of the plant (or seeds) and the location in the garden can be useful as well as any eventual previous identifications.

Flowering stem
Basal leaves
flower

Herbarium Cultivated Plants


ACCESSION NUMBER: 2007-176
Source:Hall,
location:



Ranunculaceae
Delphinium nanum



                             
Locality:Spain, Cadiz, Barbate pine Forest  12 November 2006
Alt: 38m
Field notes:Plant height 50cm. Lots of plants scattered throughout Pinus pinea forest, in shady areas, growing in sand with Cistus, Halimium, Juniperus oxycedrus and Juniperus phoenicea.
Collector:Hall, A. 123

spur
Plant specimen

Morphological key Characters

It is very important to study morphological characters of the plant in detail before starting the naming. Because those characters will be used all along to identify the species.

Perianth Flower with spurred sepals and honey leaves dissected
Perianth: 1 spurred sepal, 2 spurred upper honey-leaves, 2 lateral clawed honey-leaves
Perianth Flower with spurred sepals and honey leaves dissected
lateral honey-leaf dissection showing the lateral honey-leaves spur going into the sepal spur
lateral honey-leaf dissection showing the lateral honey-leaves spur going into the sepal spur
carpels
Gynoecium : 3 glabrous unfused carpels
Carpels
anthers stamens
Androecium: many free stamens
anthers stamens
leaf petiole
Leaves: lobed, glabrous
dissected leaf Petiole

Floral Formula and Diagram

Those diagrams can help to understand the morphology of the flower.

Delphinium Floral Diagram
Delphinium Floral Diagram
Delphinium floral formula
Delphinium Floral Formulae

Publication method

If the specimen is already named it is possible to check the identity of the plant by looking at the original description and type specimen of the taxon. To find information on the author and publication place of a taxon IPNI (International Plant Names index) is the best resource.

In this case plant name details from IPNI

Ranunculaceae Delphinium nanum DC.

Syst. Nat. (Candolle) 1: 349. 1817 [1818 publ. 1-15 Nov 1817]

Original Data:

Notes: Aegypt

DC. is the abbreviation for De Candolle who published this species in De Candolle 'Regni Vegetabilis Systema Naturale' Volume 1, page 349 and in 1817.

Original description of Delphinium nanum DC.

Original publication of Delphinium nanum by De Candolle

16. Delphinium nanum. Suberect dwarf herb, leaves pubescent and villous, lower ones 3-5 lobed, upper ones linear, inflorescence a lax raceme with 2-3 flowers, lateral honey-leaves limb orbiculate.

The type specimen is not located at Kew and might be located in Geneva. Therefore we can not compare the specimen.

The original description is very succinct and it is difficult to confirm it is the same species.

This method is certainly the most difficult one and is often only used when no other methods work. This can be useful for publishing a new species.

key method

There are no recent revision of the genus Delphinium. This plant is originally from Spain so there are two keys available, one in Flora Europaea and one in the recent Flora Iberica.

Extract from Flora Europaea Vol1 ed2

Delphinium L.
B.Pawlowski

Leaves usually about as wide as long, and deeply palmate, the lobes pinnatisect. Flowers zygomorphic. Perianth-segments 5, the upper with a spur. Honey-leaves 4 free; the 2 upper (nectariferous) with spurs inserted into the spur of the uppermost perianth-segment, and with the limb exserted; the 2 lateral with a wide limb and a narrow claw. Stamens in 8 spirally arranged series. Follicles 3(-5), free.

1Perennial; limb of lateral honey-leaves ciliate and bearded on upper surface
2 Tubers absent; seeds not covered with scales, winged at angles
3 Stems (especially above) and perianth-segments with mostly smooth, arcuate hairs; perianth-segments rather narrow
4 Perianth-segments usually 22-32mm, acuminate; hairs not crowded near apex of perianth-segments ............................................................................................................................ 3. oxysepalum
4 Perianth-segments rarely more than 23 mm, subobtuse or acute; hairs +/- crowded near apex of perianth-segments
5 Perianth-segments pale blue; petiole, even of upper leaves, not or scarcely shorter than lamina; carpels usually densely pubescent ................................................................................. 1. montanum
5 Perianth-segments deep blue; petiole, even of upper and middle leaves usually many times shorter than lamina; carpels glabrous or sparsely (very rarely densely) puberulent ....................2. dubium
3 Stems with straight hairs ot minutely scabrid arcuate hairs, or stems glabrous; perianth-segments 1-2(-3) times as long as wide, suborbicular or obovate, rarely oblong.
6 Honey-leaves blue, or the upper yellowish; leaves 3-lobed almost to base
7 Bracts and bracteoles linear; perianth-segments 10-16(-18)mm ................7. dictiocarpum
7 Lower bracts usually 3-fid, bracteoles linear; perianth-segments 15-25mm 8. middendorffii
6 Honey-leaves blackish or dark brown (if blue then leaves not 3-lobed to base)
8 Leaves +/- cordate at base; lobes rather wide, not free to base ........................... 4. elatum
8 Leaves +/- cuneate at base; lobes rather narrow, usually free to base
9 Inflorescence-axis and perianth-segments glabrous, more rarely patent-pubescent; leaf-lobes linear-lanceolate .....................................................................................................5. simonkaianum
9 Inflorescence-axis and perianth-segments covered with subappressed, minutely scabrid hairs; leaf-lobes oblong ....................................................................................................................6. cuneatum
2 Tubers present; seeds covered with membranous scales, not winged
10 Base of petiole little dilated, surrounding less than ½ circumference of stem; pedicels of lower flowers usually at least as long as flowers
11 Follicles usually 5 ..........................................................................................9. pentagynum
11 Follicles 3 ..................................................................................................10. emarginatum
10 Base of petiole strongly dilated, almost completely surrounding stem; pedicels of lower flowers usually shorter than flowers
12 Stem angled; petiole of middle and upper cauline leaves very short .....15. schmalheusenii
12 Stem +/- terete; all cauline leaves +/- long-petiolate
13 Flowes dirty blackish-violet or –purple, rather widely open; spur +/- equalling perianth-segments .............................................................................................................................14. puniceum
13 Flowers blue, violet-blue, lilac or whitish, rarely yellowish-violet, not widely open; spur usually distinctly longer than perianth-segments
14 Bracts and bracteoles ovate-lanceolate; flowers (incl. spur) 19-23mm, pale blue or whitish .............................................................................................................................13. albiflorum
14 Bracts and bracteoles linear; flowers (incl. spur) usually more than 23mm, blue, lilac or yellowish-violet
15 Stems 3-6 mm thick; flowers (incl. spur) 22-27mm ..............................................11. fissum
15 Stems 7-10 mm thick; flowers (incl. spur) 30-36 mm ...........................................12. bolosii

1 Annual or biennial; lateral honey-leaves glabrous and not ciliate (Mediterranean region)
16 Limb of upper honey-leaves unwinged; seeds few, rugose-areolate
17 Spur 1/5-1/3 as long as perianth –segments; seeds 5.5-7.5 mm ................23. staphisagria
17 Spur at least 2/5 as long as perianth-segments; seeds 3-4.5 mm
18 Inflorescence-axis, pedicels and outside of perianth-segments shortly pubescent; bracteoles inserted at base of pedicels ..........................................................................................................25. pictum
18 Inflorescence-axis and outside of perianth-segments villous-hirsute; bracteoles inserted at some distance above base of pedicels ............................................................................................24. requienii
16 Limb of upper honey-leaves with lateral wings; seeds numerous, covered with transverse membranous scales
19 Limb of lateral honey-leaves cuneate at base, gradually narrowed into a claw
20 Limb of lateral honey-leaves ovate or elliptic; spur of perianth-segments up to twice as long as segments .............................................................................................................................16. peregrinum
20 Limb of lateral honey-leaves subquadrate, with wide truncate apex; spur of perianth-segments +/- equalling segments .....................................................................................17. hirschfeldianum
19 Limb of lateral honey-leaves abruptly contacted into claw
21 Limb of lateral honey-leaves not or little shorter than claw, usually distinctly exserted, not cordate at base ............................................................................................................................... 18. ambiguum
21 Limb of lateral honey-leaves ½-3/4 as long as claw, cordate or subcordate at base
22 Limb of lateral honey-leaves oblong, 1and1/4-2 times as long as wide, exserted
23 Limb of lateral honey-leaves usually 1and1/3-2 times as long as wide; perianth-segments usually 7-9 mm .....................................................................................................................................21. gracile
23 Limb of lateral honey-leaves up to 1and1/3 times as long as wide; perianth-segments usually 5-7 mm ............................................................................................................................22. hellenicum
22 Limb of lateral honey-leaves suborbicular, included
24 Follicles and outside of perianth-segments minutely appressed-pubescent (rarely follicles glabrous) .............................................................................................................................19. halteratum
24 Follicles and outside of perianth-segments densely covered with patent hairs .20. balcanicum

Naming with infrageneric classification

When it is possible genera are usually subdivided into natural phylogenetic groups. Those groups share common characters and the species in those groups are more or less closely related at least in the morphology. This can help to reduce the choice of possible species when comparing specimen in a herbarium.

sect. Delphiniastrum DC. Perennials. Limb of lateral honey-leaves deflexed, ciliate, bearded on the upper surface. Upper honey-leaves not winged or clawed. Seeds numerous: Species 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15

sect. Delphinium.Annuals or biennials. Honey-leaves glabrous, the same colour as the perianth-segments, the upper winged, not clawed. Seeds numerous: 16,17,18,19,20,21,22

sect. Staphisagria DC.Annuals or biennials. Honey-leaves glabrous, the same colour as the perianth-segments, the upper paler or yellowish, shortly clawed, unwinged. Seeds few: 23,24,25

Taxonomical problems

Taxa names are changing continually and can be put in synonymy with other names or even split in different taxa. Therefore names that were used in the past can no longer be in use.

For example with the name Delphinium nanum DC. In the index of Flora Europaea vol1 ed 2 this is listed as a synonym of D.ambiguum L. But it is treated as a good species in Flora iberica.

To complicates matters in Flora Europaea vol1 ed1 the name Delphinium ambiguum L. is not listed. Only D. ambiguum auct. non L. is listed as a synonym of Consolida ambiguum which is a synonym of C.ajacis (L.)Schur.

But fortunately D. nanum CD. is listed in the index of Flora Europaea vol1 ed1 as a synonym of D. obcordatum DC. Name which is also in synonymy with D. ambiguum L.in Flora Europaea vol1 ed2.

Under which name Delphinium nanum DC. will be listed in Flora Europaea vol1 ed1 ?

Is it a Delphinium ?

This question should be one of the first but often botanists are familiar enough with families and genera to be able to know in which genus the specimen belongs.

Nevertheless some genera are closely related together and it can be difficult to distinguish them. Take for example Delphinium and Consolida.

Follicles 2 or more................Delphinium

Follicle 1..........................Consolida

This is one of the only character that can distinguish them.

Herbarium specimen comparison method

This method simply consists in comparing with herbarium specimen. This can be very efficient and quick but key characters and characters that are lost during the drying are then often overlooked. This method often leads to more confusion.

This table shows the index for the herbarium specimen of European Delphinium at Kew.

Index to the European species of Delphinium arranged according
to Flora Europaea Vol. I ed. 1 p. 213-216

aconiti L.

= Consolida aconiti

ajacis auct.

=Consolida ambigua

albiflorum DC.

13

alpinum Waldst. & Kit.

=4a

ambiguum

=Consolida ambigua

balcanicum Pawl.

20

cardiopetalum DC.

=21

Consolida L.

 =Consolida regalis

     ssp. arvense ( Opiz ) Graebner

=9a

cryophilum Nevski

? = 4a

cuneatum Steven ex DC.

6

dictyocarpum DC.

8

     ssp. uralense ( Nevski ) Pawl.

8b

divaricatum Ledeb.

= Consolida regalis ssp. paniculatum

dubium (Rouy & Fouc.) Pawl.

2

elatum L.

4

     ssp. austriacum  Pawl.

4c

     ssp. helveticum Pawl.

4b

emarginatum C. Presl

11

fissum Waldst. & Kit.

12

gautieri Rouy

9/1

gracile DC.

22

halteratum Sibth. & Sm.

19

hellenicum Pawl.

23

hellesponticum Boiss.

= Consolida hellespontica

hirschfeldianum Heldr. & Holzm

17

hispanicum Willk.

=Consolida orientalis

hybridum Wild. non L.

=12

intermedium Aiton

=4a

junceum DC.

=16

leiocarpum Huth

=12

litwinowii Sambuk

=7

longipes Moris

=19

loscosii Costa

= Consolida pubescens

macedonicum Halacsy & Charrel

=3

montanum DC.

1

nacladense

=4a

narbonense Huth

12

nevadense G. Kunz

10

obcordatum DC.

18

orientale Gay

= Consollida orientalis

oxysepalum Borbas & Pax

3

pallasii Nevski

=12

paniculatum Host

= Consolida regalis ssp. paniculata

pentagynum Lam.

9

peregrinum L.

16

peregrinum sensu Halacsy non L.

=23

peregrinum sensu Willk. pro max. parte non L.

=20

phrygium Boiss.

= Consolida orientalis ssp. phrygium

pictum Willd.

25

pubescens DC.

= Consolida pubescens

pubiflorum Turez.

=8

puniceum Pallas

14

pyramidatum auct., non Albov

=5

requienii DC.

26

rigidum DC.

= Consolida rigida

rossicum Litv.

7

schmalhausenii Albov

15

sergii Wissjul.

=15

simonkaianum Pawl.

5

sordidum Cuatrec.

12/1

staphisagria L.

24

tenuissimum Sibth. & Sm.

= Consolida tenuissima

thirkeanum Boiss.

= Consolida thirkeana

tiroliense Kerner

=4a

tomentosum Boiss.

= Consolida hellespontica

vechtrizianum Huth

= Consolida vechtritziana

uralense Nevski

=8b

velutinum Bertol

=12

verdunense Balbis

21

Consider natural variation and species concept and question the treatment

This is the most difficult part to consider and can explain most of the problem in naming. It explains why the same plant can have different names but not necessary being misnamed.

Natural variation is much present in plant and it is difficult to assess when a species is distinguished from an other. Those problem often appear when authors use hairiness, or leaf characters to distinguish their species.

But there is not definition for the species concept in plant so basically any opinion in species delimitation is valid.