Ericaceae & Myrtaceae

Question 1

What is the distribution of the Ericaceae family?

Answer 1

Lots in the Northern Hemisphere, some groups in the Southern temperate regions of Australia, Africa, South America and New Zealand.

Question 2

List 4 characteristics of the Ericaceae family plus some of the common plants included in this family.

Answer 2

• Distinct sepals and petals, usually 5 (3-7)
• Flowers usually with bracts/bracteoles at base
• Corolla tubular (petals at least fused at base)
• Fruit indehiscent (berry or drupe) or dehiscent (capsule)
• Includes heaths, heathers, rhododendrons, blueberri

Question 3

The ‘epacrids’ are in which subfamily of Ericaceae?

Answer 3

Epacridoideae.

Question 4

Epacrids are also known as ‘southern heaths’. Where are epacrids found?

Answer 4

Australia, NZ, South America and neighbouring areas of Asia.

NOTE: Most Australian Ericaceae plants are found within this subfamily (Epacridoideae).

Question 5

What environment are Epacrids usually found in?

Answer 5

Heathlands on low phosphorous soil.

Question 6

How many stamens and corolla lobes are usually found in the flowers of Epacrids?

Answer 6

4-5 stamens and 4-5 corolla lobes.

Question 7

Stamens are often epipetalous in Epacrids. True or false?

Answer 7

True! The stamens are inserted between the corolla lobes.

Question 8

In Epacrids, are carpels free or united? Are the ovaries inferior or superior?

Answer 8

United carpels, ovary superior.

Question 9

The fruit of Epacrids is usually fleshy. True or false?

Answer 9

True.

Question 10

Non-Epacridoideae Ericaceaes include 3 genera native to Australia, including 2 species of Rh________.

Answer 10

Rhododendron.

Question 11

The Myrtaceae family is the biggest plant family in Australia. True or false?

Answer 11

True!

Question 12

Where is the Myrtaceae family distributed?

Answer 12

Largely in the Southern Hemisphere.

Question 13

Where was Myrtaceae present c. 86 m.y.a.? What type of fossils do we have from there?

Answer 13

Gondwana. Fossil pollen from Myrtaceae.

Question 14

When did the Myrtaceae family colonize parts of the Northern Hemisphere?

Answer 14

When land masses in the Southern Hemisphere came into contact w/ those in the Northern.

Question 15

Name some of the traditional and modern uses of Myrtaceae.

Answer 15

Traditionally used for wood for canoes, bark, honey, water (Mallee roots).

Modern uses: timber, paper, oils, spices, fruit (guava, feijoa, scrub cherries).

Question 16

Eucalypt fossils were discovered in South America. How old are these fossils?

Answer 16

50 m.y. old.

Question 17

Name one of the most useful spotting characteristics of the Myrtaceae family. Explain why this characteristic likely exists.

Answer 17

All have leaves with oil glands! Likely for anti-herbivory and/or increasing flammability (which has consequences for its fire ecology).

Question 18

What are the two fruit forms found in the Myrtaceae family?

Answer 18

• Dry-fruited forms e.g. eucalypt capsule that opens by valves (splitting of top of ovary)
• Fleshy-fruited forms e.g. rainforest Lilly Pilly

Question 19

Name 5 features of Myrtaceae flowers including number of petals, number of sepals, number of stamens, symmetry type and ovary position.

Answer 19

• 4-5 petals
• 4-5 sepals
• Many stamens (usually >10)
• Actinomorphic
• Inferior ovary

Question 20

Myrtaceae flowers are pollinated by a range of different animals. What are white, open Myrtaceae flowers usually pollinated by?

Answer 20

Flies, beetles or bees.

Question 21

The fleshy fruits of Myrtaceae members are dispersed by _____.

Answer 21

birds.

Question 22

Myrtaceae flowers can sometimes have their stamens grouped together in bundles/fascicles which often sit in front of their petals. True or false?

Answer 22

True.

Question 23

What is the name of the tallest flowering plant in the world?

Answer 23

Eucalyptus regnans.

Question 24

Eucalyptus flowers have protective ‘caps’ (opercula) homologous to sepals and petals. True or false?

Answer 24

True!

Question 25

Eucalyptus flowers have a female phase first. True or false?

Answer 25

False! A male phase comes first.

Question 26

Some eucalypts retain their juvenile-looking foliage until throughout their whole life. True or false?

Answer 26

True! Some do, some do not.

Question 27

Name the three genera within the Eucalypts.

Answer 27

• Eucalyptus
• Angophora
• Corymbia

Question 28

Name three characteristics of Angophora that help to distinguish it from other Eucalypts.

Answer 28

• free sepals and petals
• opposite leaves
• sepals persist as teeth on fruit

Question 29

Name two characteristics of Corymbia that help to distinguish it from other Eucalypts.

Answer 29

• many side veins at wide angle

- often have terminal, compound inflorescences