Field Guide to Plants of Tanzania: Etymology and Eponyms for Understanding Botanical Names

By John E. Makunga

This fully revised second edition of the plant field guidebook, was written in Tanzania by an experienced author in the field of conservation. The book is well researched and prepared to suit the demand of lecturers, students, researchers, conservationists, tour guides, tourists, horticulturalists, environmental Impact assessment (EIA) experts and natural resources consultants among others. The guidebook contains plants of different growth forms, both aquatic and terrestrial ecosystems, and therefore, it provides a good platform for considerate, understanding and conserving Tanzania's flora and hence, its sustainable utilization. Up to 387 plant species from 81 families have been identified and represented by coloured photographs, also furnished by glossaries of botanical terms, illustrations of leaf types, shapes, phyllotaxy, types of inflorescence and fruits.

 

Some of the plants included in this field guidebook are rare, endemic, threatened and invasive lien species. Knowing these species, therefore, helps in augmenting management efforts to conservation authorities, individual users and other stakeholders. Etymology and eponyms are the key concepts intended to help readers in understand in a simple, fascinating and instructive way, plants' scientific names presented in this field guidebook, which basically have their roots from the Latin and Greek languages. The guidebook is well organized with valuable contents, which surely enlightens readers' understanding in plant science. The author of this field guidebook is an experienced lecturer, researcher and consultant in a variety of fields, in particular, disaster risk management, environment, climate change and nature conservation.

• Language: English
• Publisher: white falcon publishing
• Release date: Mar 20, 2024
• ISBN: 9798224129102

John E. Makunga

The author of this book, Mr. John Elias Makunga, is a Tanzanian currently working as Lecturer at Pasiansi Wildlife Training Institute in Mwanza, under the Ministry of Natural Resources and Tourism, Tanzania.  He has also served as a Wildlife Warden since 2003 to 2012 at the Anti-poaching Unit Southern Zone in Songea, Ruvuma Region. He was born on 1st September, 1977, in Nyamagana District, Mwanza Region, Tanzania. Currently, Mr.  Makunga is pursuing PhD in Disaster Risk Management at Ardhi University, Tanzania. He holds a Master's of Science degree in Climate Change and Sustainable Development   attained   from   the   University   of   Dar   es   Salaam, Tanzania, from 2013 to 2016.  He pursued his Bachelors of Arts degree in Environmental Disaster Management at the University of Dodoma, from 2008 to 2011.   Prior   to   attainment   of   University   education, Mr.   Makunga pursued a Certificate in Wildlife Management at the College of African Wildlife Management - Mweka, in Kilimanjaro Region from 2007 to 2008, and a Basic Certificate in Wildlife Management at Pasiansi Wildlife Training Institute from 2003 to 2004.  Mr. Makunga is a licenced professional consultant in the fields of disaster and conservation. He has also been involved in a number of research assignments since 2014 and has published several papers and books. Moreover, he had served as a freelance journalist since 2001, in a number of local media houses, including the Tanzania Wildlife Magazine, supported by the Tanzania Wildlife Protection Fund (TWPF). Currently, Mr. Makunga is serving as a Quality Assurance and Control Officer, along with his teaching responsibilities.     

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Field Guide to Plants of Tanzania: Etymology and Eponyms for Understanding Botanical Names

John Makunga

Published by John Makunga, 2024.

While every precaution has been taken in the preparation of this book, the publisher assumes no responsibility for errors or omissions, or for damages resulting from the use of the information contained herein.

FIELD GUIDE TO PLANTS OF TANZANIA: ETYMOLOGY AND EPONYMS FOR UNDERSTANDING BOTANICAL NAMES

First edition. March 20, 2024.

Copyright © 2024 John Makunga.

Written by John Makunga.

I would like to dedicate this work to my lovely parents. With their heartfelt support, care, prayers and endless love, I have successfully trekked to the peak of academic authorship recognition. This work is also dedicated to my family for their inspiration, vital support, tolerance and true love. I also dedicate this book to my teachers from primary school to universities, for equipping me with knowledge and skills, which have directed me to this professional writing destination. I further Dedication my book to an Optometrist (retired), Ereneo Rwelamila Kalisa of Sekou Toure Referral Hospital; Rev. Antony D'Souza, a former Parish Priest of St. Francis Xavier, Nyakahoja Parish; and Joseph W. Butiku, Executive Director of the Mwalimu Nyerere Foundation for their financial support during my Advanced Secondary School Studies. 

Field Guide to Plants of Tanzania

Etymology and Eponyms for Understanding Botanical Names

John E. Makunga

Published by White Falcon Publishing

Chandigarh, India

All rights reserved

First Edition, 2022

Second edition, 2024

© John E. Makunga, 2024

Cover design by White Falcon Publishing, 2024

Cover image by John E. Makunga

No part of this publication may be reproduced, or stored in a retrieval system, or transmitted in any form by means of electronic, mechanical, photocopying or otherwise, without prior written permission from the author.

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Dedication

I would like to dedicate this work to my lovely parents. With their heartfelt support, care, prayers and endless love, I have successfully trekked to the peak of academic authorship recognition. This work is also dedicated to my family for their inspiration, vital support, tolerance and true love. I also dedicate this book to my teachers from primary school to universities, for equipping me with knowledge and skills, which have directed me to this professional writing destination. I further dedicate my book to an Optometrist (retired), Ereneo Rwelamila Kalisa of Sekou Toure Referral Hospital; Rev. Antony D’Souza, a former Parish Priest of St. Francis Xavier, Nyakahoja Parish; and Joseph W. Butiku, Executive Director of the Mwalimu Nyerere Foundation for their financial support during my Advanced Secondary School Studies.

Contents

Dedication

AUTOBIOGRAPHY

ACKNOWLEDGEMENT

PREFACE

PLANTS TAXONOMY

1. Typhaceae (Cattail family)

2. Rutaceae (Rue or Citrus family)

3. Asphodelaceae (Aloe family)

4. Asparagaceae (Asparagus family)

5. Agavaceae (Agave or Century plant family)

6. Tiliaceae (Linden or Basswood family)

7. Ebenaceae (Persimmon or Ebony Family)

8. Myrtaceae (Myrtle family)

9. Rhamnaceae (Buckthorn family)

10. Verbenaceae (Verbena family)

11. Lythraceae (Lawsonia or Loosestrife family)

12. Convolvulaceae (Bindweed or Morning glory family)

13. Pontederiaceae (Pickerelweed family)

14. Araceae (Arum family)

15. Malvaceae (Hibiscus or Mallow family)

16. Lauraceae (Laurel family)

17. Onagraceae (Evening primrose or Willowherb family)

18. Cannabaceae (Hemp family)

19. Solanaceae (Nightshade or Tomato/Potato family)

20. Sapindaceae (Soapberry family)

21. Arecaceae (Palm family)

22. Amaranthaceae (Amaranth or Pigweed Family)

23. Boraginaceae (Borage or Forget-me-not family)

24. Salvadoraceae (Salvadora family)

25. Loganiaceae (Logania family)

26. Apocynaceae (Dogbane family)

27. Phyllanthaceae (Leafflower family)

28. Rubiaceae (Madder family)

29. Zygophyllaceae (Caltrop or Bean Caper Family)

30. Nyctaginaceae (Four o’clock family)

31. Cochicaceae (Colchicum family)

32. Polygonaceae (Buckwheat family)

33. Anacardiaceae (Cashew or Sumac family)

34. Cappparaceae (Caper family)

35. Olacaceae (Olive family)

36. Cupressaceae (Cypress family)

37. Papaveraceae (Poppy family)

38. Moraceae (Mulberry family)

39. Vitaceae (Grape family)

40. Burseraceae (Torchwood family)

41. Celastraceae (Staff-vine family)

42. Simaroubaceae (Quassia family)

43. Bignoniaceae (Bignonia, Trumpet creeper or Catalpa family)

44. Combretaceae (Combretum or Terminalia family)

45. Commelinaceae (Dayflower or Spiderwort family)

46. Lamiaceae (Mint family)

47. Poaceae (Grass family)

48. Euphorbiaceae (Spurge family)

49. Cactaceae (Cactus family)

50. Fabaceae (Legume, Pea, or Bean family)

51. Meliaceae (Mahogany family)

52. Asteraceae (Aster or Daisy family)

53. Cucurbitaceae (Gourd family)

54. Cyperaceae (Sedge family)

55. Annonaceae (Custard-apple family)

56. Salicaceae (Willow and Poplar family)

57. Crassulaceae (Feltbush, Stonecrop or Orpine family)

58. Pinaceae (Pine family)

59. Casuarinaceae (Beefwood family)

60. Bombacaceae (Bombax, Baobab or Kapok family)

61. Araucariaceae (Araucaria family)

62. Strelitziaceae (Bird-of-paradise plants)

63. Amaryllidaceae (Amaryllis or Narcissus family)

64. Portulacaceae (Furslane family)

65. Acanthaceae (Acanthus family)

66. Brassicaceae (Mustard or Cabbage family)

67. Nymphaeaceae (Water lilies family)

68. Hypericaceae (St. John’s wort family - formerly Clusiaceae)

69. Chrysobalanaceae (Coco plum family)

70. Orobanchaceae (Broomrape family)

71. Sterculiaceae (Cacao family)

72. Musaceae (Banana family)

73. Molluginaceae (Carpetweed family)

74. Oxalidaceae (Wood Sorrel family)

75. Urticaceae (Nettle family)

76. Hypericaceae (St. Johnswort family)

77. Melastomataceae (Melastoma family)

78. Aristolochiaceae (Birthwort family)

79. Rosaceae (Rose family)

80. Orchidaceae (Orchid family)

81. Loranthaceae (Showy Mistletoe family)

GLOSSARY OF BOTANICAL TERMS

ILLUSTRATED GLOSSARIES

SUGGESTED READINGS

INDEX

AUTOBIOGRAPHY

Mr. John Elias Makunga, the author of this book, is a Tanzanian employed in the Ministry of Natural Resources and Tourism, currently working as an academic staff at Pasiansi Wildlife Training Institute in Mwanza, Tanzania since October 2012. He has also served as a Wildlife Warden at the Anti-poaching Unit Southern Zone in Songea, Ruvuma Region, from 2003 to 2012. Mr. John Elias Makunga was born on 1 st September 1977 in Nyamagana District, Mwanza Region, Tanzania. In terms of academic profile, Mr. Makunga is currently pursuing a PhD in Disaster Risk Management at Ardhi University, Tanzania, specializing in Wildfire Risk and Social-ecological Resilience.

The author holds a Master’s of Science degree in Climate Change and Sustainable Development obtained from the University of Dar es Salaam, Tanzania, from 2013 to 2016. He pursued his Bachelor of Arts degree in Environmental Disaster Management at the University of Dodoma from 2008 to 2011. Mr. Makunga obtained his Ordinary Secondary School Education from 1993 to 1996 and Advanced-Level Secondary Education from 1999 to 2001 at Mwanza Secondary School. Additionally, he attended primary school at Nyakato Primary School located in Mwanza Municipality, Tanzania, from 1986 to 1992.

Prior to attaining his university education, Mr. Makunga pursued a Certificate course in Wildlife Management at the College of African Wildlife Management, Mweka, in the Kilimanjaro Region from 2007 to 2008. He also obtained a Basic Certificate in Wildlife Management at Pasiansi Wildlife Training Institute from 2003 to 2004. Both of these wildlife colleges are located in Tanzania. In addition, Mr. Makunga has attended several short courses in Geographic Information System (GIS) and Remote Sensing (RS) at the University of Dar es Salaam and Nelson Mandela African Institution of Science and Technology in Tanzania. These courses have enhanced his expertise in Land Use/Cover Change detection and Modeling, particularly in relation to Climate Change and Disaster Risk Management. Mr. Makunga possesses a wide range of management, professional, and research experience.

During his stay at the University of Dodoma, Mr. Makunga was the founder of the University’s Environmental Club (abbreviated as ESCUDOM) and became the first chairperson until 2011. He was gazetted as a Public Prosecutor by the Office of Public Prosecutions (DPP) in Tanzania to prosecute wildlife-related crimes since 2012 and was registered as a Technical Teacher by the National Council for Technical Education (NACTE) in 2017. At Pasiansi Wildlife Training Institute, Mr. Makunga has taught a number of modules, predominantly Wildlife Law Enforcement, Mammalogy and Botany, for several years, and has become one of the few experienced plant identification professionals at the Institute and beyond.

Moreover, he embarked on a freelance journalism career in 2001, working for various local media houses, including the Press Service of Tanzania (PST), Sahara Media Group (SMG), formerly known as Sahara Communication & Publishing Company Ltd (SCPC) and Tanzania Wildlife Magazine, which is supported by the Tanzania Wildlife Protection Fund (TWPF). Due to his exceptional writing and communication skills, Mr. Makunga was appointed as a Public Relations Officer at Pasiansi Wildlife Training Institute, for five years from 2016 to 2020. In addition to his teaching and research responsibilities, Mr. Makunga also served as a Quality Assurance and Control Officer. Currently, he is supervising the Training Support Service Unit, which includes the Library and Biological Laboratory at Pasiansi Wildlife Training Institute.

ACKNOWLEDGEMENT

The accomplishment of this field guidebook was not easy without support from other people. Their heartfelt devotion of time, mindset, and financial assistance was the secret to the success achieved. The foremost gratitude is given to Almighty God, who inspired me with the idea of embarking on the endeavor of writing this book with a focused mind on plant identification. Truly, without God’s mercy and love, nothing would have progressed. On the other hand, my family members made an enormous contribution to this work. My parents, the lovely Mama Teresia Mchella Fungo and my lovely father Mzee Elias Makunga Marwa, deserve immense gratitude for their invaluable care, guidance, and prayers since my childhood.

Notwithstanding the miserable economic hardships my family faced during my absence, the budget for my subsistence remains intact. More importantly, my family members continued praying for me during my absence, which was manifested by frequent trips in the wilderness and elsewhere for plant identification. I am therefore utterly grateful to my gorgeous and superego wife, Veronica Alfredy Maboko (Wildlife Conservationist), the mother of my lovely children, for enduring my tiresome reading and writing responsibilities, which demanded much of my time on the computer. Regardless of her child-caring and official assignments, my wife kept devoting her time to advice and encouragement.

Financial support was of paramount importance for achieving the accomplishment of my field guide project. Again, I candidly convey my intense gratitude to my wife for being passionate about my book project and providing positive advice and support. Her heartfelt willingness to effortlessly support my pursuits to get this revised edition published is truly appreciated. At this point, I remember and sincerely thank my children: Innocent, Bryan, and Rayton (my youngest) for their love. Their happiness and recognition of both me and their mother as their parents is more significant than any tangible contribution they could have made. They all deserve my deepest gratitude.

My writing concepts would not have been converted into reality without the publisher, White Falcon Publishing Solutions LLP, playing a major role in translating my knowledge and skills into publication. This has led me to global recognition in the field of Botany. Therefore, I would like to express my gratitude to all the company personnel including the management team, book designers and editors for their incredible professionalism and experience in shaping my ideas into a substantial academic and scientific approach.

I will not be fair if I overlook the momentous positive thoughts, considerations and encouragement of my young brother, Lawyer, Sospeter Mateso Elias Makunga (famously known as Imani), towards the focus of this book. He regularly communicated to me to know the progress of the entire process of my book project. Lastly, I thank my fellow lecturers and other co-workers for their best wishes during the activities I undertook to accomplish this work. Finally, yet most importantly, I am indebted to Professor Abiud Kaswamila of the University of Dodoma (Department of Geography and Environmental Studies) for his valuable academic advice. Along with this acknowledgement, I also remember those who assisted me in understanding Local name of plant species included in this guide book, including Mr. Kengere Magegebu and Rogatus Charles Ntenganija, both residents of Mwanza in Tanzania.

To all of these people, I say thank you and may you be blessed.

PREFACE

Tanzania is blessed with vast biological diversity, encompassing a wide range of plants and animals, including some that are unique to the region, endemic, rare, or at risk. It is essential to implement wise management practices to safeguard the country’s biodiversity. Regardless of any specific strategy employed in managing plants, the identification of resources is of utmost importance. Plant identification for example , plays a critical role in effective management of invasive species, which pose a significant threat to our precious biological diversity.

As a result, ecological monitoring and overall management budgets in protected areas must acknowledge the significance of plant identification. To date, approximately 390,900 plant species are known to science, including 462 families of flowering plants and vascular plants worldwide. It has also been reported that around 2,000 new plant species are discovered or described each year, many of which are already on the brink of extinction. Despite this achievement, numerous individuals remain unfamiliar in diverse ecosystems.

The use of complex botanical names, derived from Greek and Latin scientific terms, further complicates matters and hinders the interest of many people in identifying plants. Lack of knowledge in plant identification can, therefore, upsurge risks to both biodiversity conservation and people’s lives. Among other things, knowing the location of the plant helps in understanding the status of that particular plant, can expedite plants identification efforts and enhance rational ecological management decisions. For this reason, botanists, researchers, conservationists, agriculture professionals, and university or college students in plant-related professions need to be acquainted with sufficient knowledge in plant identification for efficient management of plant resources.

Different plant growth forms, including trees, shrubs, graminoids (grasses and sedges), forbs, herbs, climbers (lianas or vines), succulents, epiphytes and parasitic plants, are included in this revised edition. This field guidebook is user-friendly and simplified in terms of coherence and intelligibility. It has taken on board the challenges associated with the use of Latin and Greek names in botanical studies by tracing their origin and translating their meaning into English, allowing users to effortlessly understand plant species.

A total of 387 plant species from 81 plant families are included in this revised edition. The author identified these species from a variety of aquatic and terrestrial ecosystems in Tanzania, primarily from five wildlife protected areas: Burigi-Chato National Park, Serengeti National Park, Ikorongo/Grumet Game Reserve, Loliondo Game Controlled Area, and Ngorongoro Conservation Area. Additionally, plants were identified in various regions of Tanzania outside of the protected areas, including Mwanza, Shinyanga, Mara, Kagera, Arusha, Kilimanjaro, Ruvuma, Coast (Pwani), and Dar es Salaam. Furthermore, some plants were identified near the borders of Kenya, Uganda, Mozambique, and Rwanda justifying similarity and relevance in terms of plant distribution in neighbouring countries.

The information used in this field guidebook is unique and fascinating, as very few field guidebooks available in Tanzania and East Africa generally have such similar information. Therefore, it is anticipated that this book will inspire conservation practitioners, researchers, students, tour guides, farmers (including gardeners), and other people interested in plant identification and management (taking into consideration the challenges and/or uniqueness of invasive species, weeds, rare, and other valuable plant species). I hope that this field guidebook will increase interest among plant professionals in plant identification, research, ecological monitoring, and management in protected areas and elsewhere globally.

PLANTS TAXONOMY

In science, the practice of classifying organisms is called taxonomy. The word originates from two Greek words, namely; taxis and nomia. Taxis means arrangement or orders and Nomia means method or system. Therefore, taxonomy refers to the method of arrangement or the system of classification. The primary criterion for grouping plants in taxa is evolutionary relationship. Classification of living organisms is called Natural Classification when it describes relationships that taxonomists think are real in nature. A distinctive feature of this type of classification is the use of as many characters as possible to establish a solid evolutionary basis.

The natural classification differs from Artificial Classification, which is based on non-evolutionary, special-purpose criteria. Carolus Linnaeus (1707 - 1778) introduced the concept of binomial nomenclature in his significant work called Systema Naturae (first edition in 1735). In this work, nature was divided into three kingdoms: minerals, vegetables, and animals. Linnaeus established five ranks: class, order, genus, species, and variety.

There are a number of classification levels below the species, with the most commonly used levels being subspecies and variety, abbreviated to subsp. (or less usefully ssp.) and var., respectively. This allows for further subdivision of plant groups to reflect the variation in form and distribution we see in nature. Whenever a subspecies, variety, or any other subdivision below the rank of species is published, an additional name called an autonym is automatically generated.

Scientific names

The scientific name of a plant is considered to be in Latin. However, many scientific names are in Greek, some are a combination of Latin and Greek, while others are derived from many other languages. The International Code of Botanical Nomenclature, also called the Botanical Code or ICBN, governs the formation and use of botanical names of plants in Latin form. The ICBN deals with the naming of taxonomic groups (abbreviated to taxa; singular taxon) and arranges them in a hierarchical order in consecutively subordinate ranks.

The scientific name of a plant is composed of three names: the genus name, the specific epithet, and, if needed, an infra-specific epithet is added (mainly to recognize variation within a species). At the simplest level of scientific classification, each plant has a name made up of two parts: a genus name and a specific epithet. Together, these two names are referred to as a binomial. The genus name describes the type of plant, such as millet. The species name describes the individual plant within the genus, such as finger millet.

Genus Name

The genus starts with a capital letter and represents a group of plants (like other living organisms) with similar characteristics. All plants in a genus will share a recent common ancestor and look similar to each other. They are all likely to need similar growing conditions and will have similar pest and disease tolerance. The genus name is written with a capital initial letter, e.g. Pinus, Lantana, etc., and when written in connection with a specific epithet, it is placed in parentheses.

Genus names that end in -us, -er, or -on are usually masculine. However, the genera of trees ending in -us (e.g. Pterocarpus, Prunus, Cataranthus, Pinus, Cissus) are considered feminine. For example, the names of most rivers and mountains are masculine, unless they end in -a or -e. Genus names that end in -a, -ago, -ix, -odes, -oides, -is, and -es are usually feminine. The names of most countries, islands, cities, and trees are feminine. Genus names that end in -um and -dendron are neuter (a plant having neither functional pistils nor functional stamens, i.e. both male and female reproductive organs are absent).

Species

Some definitions of species have been documented. Species are the basic unit of biological classification, consisting of organisms that share similar physical and molecular characteristics and are capable of reproducing successfully. Species can also be defined as a group of similar organisms sharing a common gene pool and interbreeding freely, producing fertile offspring. Species occur in the form of many interbreeding groups called populations. The group of similar organisms which can breed among themselves is therefore called a species.

The component populations of a species, however, have the capacity, either directly or indirectly, to interbreed with one another. Such interbreeding is not a property of the component organisms. It is the exchange of genetic material, or gene flow, throughout the population as a whole. The scientific name of a species is a binomial combination (binomen) in Latin form consisting of a name of the genus followed by a single specific epithet, such as Lilium candidum, where Lilium is the genus name and candidum is the specific epithet. Specific epithets are written with a lowercase initial letter.

Subspecies Name

A subspecies (ssp. or subsp.) is often useful for recognising variation within a species. Sometimes, within a species, small groups of plants can be found that are slightly different from the norm, having evolved in a distinct geographical area. The subspecies were conceived of as genetically distinct, geographically separate populations belonging to the same species and, therefore, interbreeding freely at the zones of contact. This difference is noted using subsp. after the main scientific name. For example, Cannabis sativa subsp. Indica (a subspecies of hemp/marijuana).

The full name of a subspecies is composed of three name components (genus name, species epithet, and infra-specific epithet), followed by the subspecies/infra-specific marker subsp., the species author string (e.g. L. or Linn. for Linnaeus), and the subspecies author string (infra-specific author string). An exception is when the subspecies epithet is the same as the species epithet (an autonym), in which case there is no subspecies author. For example, Pisum sativum L. subsp. arvense Poir. This is a subspecies of a pea.

Variety

Variety, that is, a botanical variety, is a rank in the taxonomic hierarchy below the rank of species and subspecies and above the rank of form - form/variety/subspecies/species. Variety names are given when the mutation occurs in nature. The term var. is placed after the specific epithet and is not underlined or italicised (Meche & Wm, no date), e.g. Eleusine coracana var. alba, Eleusine coracana var. fusca, Eleusine coracana var. stricta, which are some of the varieties of finger millet grown in Tanzania.

Given below are some examples that include a variety in the scientific name: Arachis hypogaea var. hypogaea (a variety of groundnut), Euphorbia bussei var. kibwezensis (a variety of pawnbroker tree); Cannabis sativa var. sativa (a variety of marijuana/hemp), and Sansevieria trifasciata var. Laurentii (a variety of snake plant).

A Difference between Variety and Cultivar in Plant Taxonomy

A variety refers to a variation within a plant species that develops naturally in the environment. Unlike a cultivated plant, a variety does not require human intervention to grow and reproduce. Seeds from a specific variety will often grow true to type, meaning that their offspring will retain the parent plant’s unique characteristics. When writing a variety name within a plant’s full scientific name, the species name comes first, followed by the abbreviation var. and then the variety name, all lowercase and italicised.

On the contrary, a plant cultivar refers to a variation within a plant species that has been developed by a human horticulturist through controlled plant breeding, as opposed to occurring naturally. The term cultivar is a portmanteau of cultivated variety. The cultivar name is added after the genus or specific epithet and is put in single quotes without italicisation, e.g. Tradescantia pallida ‘purpurea’.

Common or Vernacular Names

Common, or sometimes called, vernacular names have evolved over centuries in different languages and are used within a particular geographical region. One plant species may be known by several different common or Local name and one name may apply to several different plants. Common names are not universal, therefore, many common names assigned to a single plant are confusing and may lead to misidentification. However, there is no international convention or guildeline governing the way common names can be written or used is species identification.

Family Names

Family names are neither italicised nor abbreviated, such as subsp. or sp. These names end with the letters -aceae and are derived from the name of a genus. For example, Apiaceae (derived from the genus Apium) and Rosaceae (derived from the genus Rosa). However, there is an exception to this rule for long-standing family names that are descriptive and not based on genus names. In such cases, their use as alternative names is authorised.

For example, although Apiaceae is based on the genus Apium, the long-standing name Umbelliferae is permitted as an alternative. Likewise, Poaceae, based on Poa, is better known by some as Gramineae. Additionally, Asteraceae is frequently known as Compositae. Eight well-known families (Table) also have older descriptive names, which are still in use and approved by the Botanical Code.

Table: Traditional Plant Families

Principles of Botanical Nomenclature

The science of naming plants, or ‘nomenclature’, is governed by a series of internationally accepted rules and regulations, contained in two codes: The International Code of Botanical Nomenclature (ICBN or Botanical Code) and the International Code of Nomenclature for Cultivated Plants (ICNCP or Cultivated Plant Code). The International Code of Botanical Nomenclature sets out the rules for giving and using the scientific names of plants at all ranks in the taxonomic hierarchy, including the familiar family, genus, and species.

The International Code of Nomenclature for algae, fungi, and plants (ICNafp) deals with the naming of taxonomic groups (abbreviated to taxa; singular taxon), which are arranged in a hierarchical order with consecutively subordinate ranks. The levels of classification, from highest to lowest, include Kingdom, Phylum (plural: Phyla) or Division (when used for plant classification), Class, Order, Suborder, Family, Genus (plural: Genera), Species (plural: Species), and Subspecies.

There are six principles that guide the decisions concerning the International Code of Botanical Nomenclature.

Principle I: Straightforward Principle: Botanical nomenclature is independent of zoological and bacteriological nomenclature. If an organism is considered a plant, then it must be named in accordance with the Botanical Code. If it is considered a bacterium, it must be named according to the Bacteriological Code, etc.

Principle II: Type Principle: The application of names of taxonomic groups is determined by means of nomenclatural types. For vascular plants, such as grasses, a nomenclatural type is a herbarium specimen that has been deposited in a herbarium. A nomenclatural type anchors the meaning of a name. If there is an argument as to what kind of plant the author of a name meant by a particular name, one examines the type specimen.

No matter which taxonomic treatment is followed, the name must be used in a sense that includes its type specimen. If, as occasionally happens, the author of a new name provides a description that does not match the type specimen, it is the type specimen, not the description, that determines which kind of plant is referred to by the name in question.

Principle III: Priority Principle: If a taxonomic group has been given two or more names, the correct name is the first name that meets the Code’s standards for publication. This means that the priority of a name dates from the time it was first published and made known to other botanists. Writing the name in a letter (or an email) to a colleague does not count, nor do notes made on herbarium sheets.

Principle IV: Uniqueness Principle: There is only one correct name for a particular taxonomic group within a given taxonomic treatment. It is the central principle upon which all the rest of the code is based. If people disagree on the taxonomic treatment, they will consider different names to be correct. However, within any treatment, each taxonomic group has only one correct name.

Principle V: As-it-should-be Principle: Scientific names of taxonomic groups are treated as Latin regardless of their derivation.

Principle VI: Retroactivity Principle: The Rules of nomenclature are retroactive unless expressly limited. The Retroactivity Principle means that anyone proposing a change in the Code needs to consider the effect that the proposed change will have on names published in a wide range of literature and over a considerable period. This is an intimidating requirement, which is why all