Multi-access key to the Brassicaceae of Victoria

Introduction

The multi-access key to the Brassicaeae of Victoria is a key to all 107 Brassicaceae taxa that are known to occur in Victoria, both native and introduced. It contains 31 characters to help distinguish taxa from each other with, including place of occurrence, plant size, and several morphological features both vegetative and reproductive. It differs from the dichotomous keys provided in VicFlora by giving the user the flexibility to choose from one of the 31 characters provided rather than the user having to commit to investigate the particular features being questioned in the dichotomous keys. This has the benefit of:

1. avoiding having to answer questions relating to a feature that may not be present in the sample when being identified,

2. potentially being able to identify a taxon without needing to comprehend the most technical terminology and

3. allowing the rapid identification of taxa with distinct features rarely encountered in the family

To use the key the user selects a feature from the features in the top left Features Available panel and clicks on the state present in their specimen to be identified. Once selected this feature and state will show as being selected in the Features Chosen panel directly below the Features Available panel. To undo a selection, click on the box next to the state chosen in the Features Chosen panel to erase the tick in the box. Once a feature state is chosen all the taxa that do not possess the chosen feature state are discarded in the bottom right Entities Discarded panel and those that do possess the chosen feature state are retained in the top right Entities Remaining panel. The user continues to choose further character states present in their specimen until identification is achieved. To restart the key when finished select the restart key icon represented by the two green arrows in the top left corner of the screen.

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General helpful hints

For the most effective use of this key the user is encouraged to read the help guides for each character and state before submitting an answer for that character and state. Help guides and photographs can be found by clicking on the page icons beside characters and states. This help will reduce the chance of misinterpretation of the character and state. Some information and definitions required for interpreting a state may be given under character so users are encouraged to read the help guide for the characters before the states. When taking measurements or assessing which state a character exists in for the taxon being identified a typical plant and plant part should be used. Typical is here interpreted as a close representation of the average plant in terms of size and stature in a population and a plant part that represents the average condition for that character (e.g. average length, the most frequently observed shape etc.). The characters provided concern the adult plant and consequently when using these characters the plant chosen should be reproductively mature. For some of the characters it is possible for some taxa to possess more than one character state for the character. In such cases either correct character state can be chosen. When taking measurements be precise e.g. if a capsule is 2.9 mm long enter 2.9 mm long rather than rounding up to 3 mm and entering that.

To help identify the specimen to be identified as quickly as possible the best option can be used. This option highlights which characters should be used first to discard the maximum number of taxa among the remaining taxa. To use the best option select the best icon given as a blue wand at the top of the screen. For some similar taxa such as closely related species or subspecies within a species it may become time consuming to keep using the key until one taxon remains. In such instances the user can use the dichotomous key and profiles to help distinguish between the remaining similar species.

Occurrence

One character that refers to where a plant can be found.

Natural Region

Victoria has been divided into 16 natural regions. For this character the user determines which natural region the plant that is to be identified was found in to enter for this character. Whether a taxon is regarded as occurring in a particular natural region or not is dependent on whether the taxon has been previously documented as occurring in that natural region or not. There is a remote possible that a taxon occurs in a natural region but has not yet been documented in that natural region. In such a case the key will not recognise that taxon as occurring in that natural region which will result in a misidentification for the user. This issue may be particularly relevant to newly introduced species which may be still expanding their range through Victoria or for taxa that are not collected often. Due to these issues we suggest that this character be one of the first characters investigated as a potential reason for misidentification.

Plant

These two characters refer to the plant in its entirety.

Habit

The general growth form and duration of the plant, this character consists of three states.

Annual

Plants that live for only one year and then die.

Herbaceous perennial

Plants that live for more than one year and lack woody stems. Plants that are small in stature when reproductive generally fall into this category, however, some herbs can become large but still do not produce woody stems and branches.

Woody perennial

Plants that live for more than one year and have woody stems and branches. Small shrubs often referred to as subshrubs are included in this state.

Maximum Height

This is a measurement in centimetres (cm) from the base of the plant at ground level to the highest point on the plant. If the plant is a herb with most of its height contributed by the reproductive parts (inflorescence and infructescence) then the measurement includes these reproductive parts

Root

Root type

The main root structures formed. This character has two states.

Stolon/rhizome

Plants with often long, usually lateral main roots from which new shoots emerge. These long stem-like roots may either be below ground (rhizomes) or run along the surface where they are often sheltered by surrounding vegetation or litter (stolons).

Taproot/network

The most common root structure of most plants. These lack any specialised underground structures, other than the typical root network (ie. a main root (or few roots) from which smaller roots may then branch off from.

Stem

This character refers to the main axis (stem) of the plant.

Stem indumentum

Covering(s) present on the on the stem (typically hairs). Ideally young stems should be inspected as stems may lose hairs with age. This character has six states.

Stems glabrous

Stems completely devoid of any type of hairs (glabrous). Stems may have a waxy glaucous covering.

Stems with simple hairs

Stems with hairs that are unbranched and lack glands or any other feature. These may be unicellular or multicellular, straight or curved, held erect or against the surface.

Stems papillate/glandular

Stems with a covering of small elongated protuberances (papilla) or glands. Glands usually appear as a spherical structure on the surface of the stem or the tip of a hair.

Stems tuberculate/scabrid

Stems with a covering of warty outgrowths. These are often hardened and may be quite sharp or rough to touch.

Stems with bristles

Stems with hairs that stiff, ridged, hard or flexible, sometimes with a sharp point. These are often straight, but can be curved or have a bend.

Stems with branching/medifixed/stellate hairs

Stems with hairs that have two or more branches or arms. These may consist of a central stalk (sometimes this is very short) which is then branched into two (medifixed) or more arms, or 2-several arms arising from a central point on the stem surface.

Leaf

This group of nine characters refers to the main photosynthetic and green organ (leaf) of the plant. Avoid selecting leaves close to inflorescences and flowers or smaller leaves sprouting from the junction (axil) of larger leaves and the stem as these leaves are often not a good representative of the typical size and shape of the leaves of the plant.

Leaf length

This character requires the user to measure and enter the distance in centimetres (cm) from the point of attachment to a stem to the apex or end of the leaf. For taxa that have a distinct leaf stalk or petiole this measurement includes the petiole as well as the expanded blade or lamina section.

Leaf dissection

The degree of dissection (e.g. lobes/teeth etc.) along the leaf margin. This character has four states.

Entire

Leaves that are completely intact along the edge without any incisions or teeth. Margins may be somewhat wavy or undulating.

Small teeth/lobes

Leaves largely entire except for few-many small teeth or lobes along the margin.

Lobed/toothed

Leaves with sharp or rounded teeth or lobes along the margins that are incised up to about half of the way to the mid-vein.

Pinnately-lobed/pinnate

Leaves that have segments that are formed by an incision of at least half of the way to the mid-vein.

2- or more times divided

Leaves that are divided into segments (pinnae) that are then further incised into lobes or pinnae (bi- or tri-pinnate).

Leaf attachment

The manner in which the leaf is attached to the stem. This character has three states.

Sessile and stem-clasping

Leaves attached directly to the stem without any connecting stalk (petiole), or with a minute stalk (c. <0.5 mm long), with the leaf blade or lobes of the blade of a pinnatisect leaf clasping or wrapping around the stem.

Sessile/subsessile, not stem-clasping

Leaves attached directly to the stem without any connecting stalk (petiole), or with a minute stalk (c. <0.5 mm long), but the leaf blade (including any lobes) does not wrap around the stem.

Petiolate

Leaves attached to the stem by a stalk (petiole) at the base of the leaf. In some cases the petiole may only be a few millimeters long.

Leaf indumentum

Covering(s) present on the on the leaves (typically hairs). Ideally young leaves should be inspected as leaves may lose hairs with age. This character has six states.

Leaves glabrous

Leaves that are completely devoid of any type of hairs (glabrous).

Leaves with simple hairs

leaves with hairs that are unbranched and lack glands or any other feature. These may be unicellular or multicellular, straight or curved, held erect or against the surface.

Leaves papillate

Leaves with a covering of small, elongated protuberances (papilla).

Leaves tuberculate/scabrid

Leaves with a covering of warty outgrowths. These are often hardened and may be quite sharp or rough to touch.

Leaves with bristles

Leaves with hairs that stiff, ridged, hard or flexible, sometimes with a sharp point. These are often straight, but can be curved or have a bend.

Leaves with branching/medifixed/stellate hairs

Leaves with hairs that have two or more branches or arms. These may consist of a central stalk (sometimes this is very short) which is then branched into two (medifixed) or more arms, or 2-several arms arising from a central point on the stem surface.

Flower

These characters refer to the structure housing the reproductive organs of the plant along with the petals and sepals.

Sepal

The outer whorl of non-fertile floral parts, these consist of 4, usually green and herbaceous appendages.

Sepal length

This character requires the user to measure and enter the distance in millimetres (mm) from the base to the apex or end of the sepal.

Petal

Petal length

This character requires the user to measure and enter the distance in millimetres (mm) from the base to the apex of the petal. Petals often consist of a narrow basal section (claw) and expanded upper section (limb). Users need to measure both limb and claw of a petal.

Petal colour

The predominant colour of the petals. This character has four states.

Petal venation

The colour of the veins on the inner surface of the petal. This character has two states.

Venation dark or contrastingly coloured

Petals with veins that are darker or contrastingly coloured to the petal lamina (e.g. yellow petals with dark brown veins, or white petals with purple veins).

Venation not in contrast to colour of petal lamina

Veins that are not a different colour to the petal lamina. In many cases veins might not be apparent. Veins that are distinct but not in stark contrast (e.g. yellow petals with slightly darker yellow veins) are also included in this state.

Petal apex

The shape of the tip of the petals. This character has three states.

Petals rounded/notched

Tips of petals are curved, rounded, flattened (truncate) or with a slight notch.

Petals bifid

Tips of petals are deeply divided into 2 or more lobes.

Petals tapered to a point

Tips of petals gradually taper to a point, which may ultimately be obtuse or acute.

Stamens

The male reproductive organs of a flower i.e. stamens (androecium).

Stamen number

The number of fertile stamens present on a flower. Only stamens that are fertile (i.e. have an anther that produces pollen) should be included. This character has three states.

Fruit

These characters refer to the structure that bears the seed(s), usually a siliqua or silicula (depending on the length).

Fruit length

The length of the fruit in millimetres (mm) from the point of attachment to the pedicel to the tip (including the persistent style, sterile beak, or distinct segments).

Fruit width (mm)

The distance in millimetres (mm) across the widest part of the fruit.

Fruit shape

The overall shape of the fruit. This character has four states.

Fruit linear

Fruits that are narrow and relatively consistent in width from base to tip. These are typically more than 3 times as long as wide (siliqua).

Fruit narrow elliptic to spherical

Fruits that are typically widest about the middle and taper towards the apex and base. These are often less than three times as long as wide.

Fruit reniform/cordate

Fruit roughly as wide as long or longer than wide and notched at the base e.g. kidney-shaped (reniform) or heart-shaped (cordate).

Fruit obovoid/obtriangular

Fruits that are clearly wider towards the apex.

Fruit architecture

The three-dimensional shape of the fruit. This character has two states.

Compressed or flattened

Fruits that are flattened, compressed or lenticular in cross section. This typically relates to the valves being flattened or very strongly keeled.

Terete or quadrangular

Fruits that are more or less circular (terete) or quadrangular in cross section (i.e.. roughly as wide as long in section). This typically relates to the valves being curved or keeled.

Fruit orientation

The direction in which the fruit is orientated. This is generally governed by the petiole. This character has three states.

Spreading or ascending

Fruits that are erect or spreading outwards from the stem (pointing upwards or sideways).

Appressed to stem

Fruits that are held erect against the stem.

Pendent

Fruits that are drooping or pointing downwards.

Fruit indumentum

Covering(s) present on the on the fruits (typically hairs), these are usually on the valves. This character has two states.

Fruits glabrous

Fruits that lack hair (glabrous).

Fruits hairy

Fruits (principally the valves) with hairs or bristles.

Fruit margins

Ornamentation along the margin or edges of fruit. This character has two states.

Fruits winged

Fruits that have a thin flange, membranous expansion extending beyond the normal outline of the fruit.

Fruits not winged

Fruits lacking an extension beyond the normal outline of the fruit, but may have minor ridges associated septum, or the venation or keel on the valve.

Fruit apex

The shape of the tip (apex) of the fruit. This character has four states.

Fruit notched

Tips of fruits have a shallow notch in the middle, often due to the two valves slightly exceeding the septum. Fruits with a persistent style sitting in this notch should also be included in this state.

Fruit deeply bifid

Tips of fruits with a deep cleft in the middle, appearing 2-lobed at the apex. The persistent style may also be present, making the fruit appear somewhat 3-lobed.

Fruit rounded/pointed

Tips of fruits rounded, curved or flattened, or come to a fine point, often due to the presence of the persistent style.

Fruit beaked

Tips of fruit with a large, usually sterile appendage (>2.5 mm long). This is often thinner or appearing as a separate segment.

Fruit dehiscence

The method in which fruits open to release seed (or the lack of any such opening). This character has three states.

Dehiscent by valves

Fruits that split open to release seeds by the detachment of the valves from the central septum.

Breaking into segments

Fruits that articulate between the seeds, breaking into short segments.

Indehiscent

Fruits that do not open to release seed.

Septum position

The position of the septum (typically a narrow rim to which the valves attach) in relation to the width of the fruit. This character has two states.

Broadest part of fruit or fruit terete

Fruits with the septum is on the broadest part of the fruit, with valves are flattened or curved with a depth that does not exceed the width.

Narrowest part of fruit

Fruits with the septum on the narrowest part of the fruit, typically with the valves very strongly keeled, with the depth (the length from the tip of the keel to septum) exceeding the width (the distance between the two ends of the valve that are attached to the septum).

Fruit venation

The number of lines (nerves or veins) that run lengthwise along the surface of the fruit valve.

Veins inconspicuous

Fruits with no prominent vein(s) that span the length of the valve. Fruits may have a prominent septum visible on either side of the valves. Fruits with reticulate venation that lacks a prominent central vein(s)] should be included in this state.

1 prominent vein

Fruits with one prominent vein running along the surface of the fruit valve (this is typically in the middle of the valve)

> 1 prominent vein

Fruits with more than one prominent vein running along the surface of the fruit valve. This often consists of one prominent central vein with 1-several slightly fainter veins on either side.

Fruit constriction

The degree to which the fruit valves sit against (and constrict around) the seeds

Not constricted between seeds

Fruits that are not constricted between seeds, with the valves appearing flat or slightly wavy along the length of the valve.

Strongly constricted between seeds

Fruits that are strongly constricted between the seeds, with the valves appearing to bulge out and then tightly taper between seeds.

Pedicel

These two characters relate to the stalk (pedicel) attaching the fruit to the stem.

Pedicel length

The length of the stalk (pedicel). Ideally mature fruits should be examined for this character. This character has three states.

Shorter than fruit

The stalk is shorter than the length of the fruit.

Equal length to fruit

The stalk is more or less equal in length to the fruit

Longer than fruit

The stalk is longer than the length of the fruit.

Pedicel indumentum

Covering(s) present on the on the pedicel (typically hairs). This character has two states

PedicelGlabrous

Fruits that lack hair (glabrous).

Pedicel hairy

Pedicels with at least some hairs (usually simple hairs of papillae).

Seed

These two characters relate to the number and arrangement of seeds within a fruit.

Number of seeds per fruit

The total number of seeds within a single fruit. Ideally fully-formed fruits should be examined for this character.

Seed position

The arrangement of seeds within a chamber (locule) of the fruit. Users need to establish if seeds sit in a single row or two rows per locule.