| ECOTYPE | Distinct species (in a particular habitat) |
| BIODIVERSITY | The variety of plant and animal life in the world or in a particular habitat (12) |
| BIOMASS | Form of energy produced from organisms that once lived. It's also the term for the weight or total quantity of living organisms of one animal or plant species or of all the species in a community. (7) |
| APES | Earth's ruling species, in a 1968 science fiction movie |
| REAGENT | Chemical species in a reaction |
| FLORA | Plants of a particular habitat; girl's name |
| AVIFAUNA | The birds of a particular habitat |
| MEGAPODE | There are a dozen species of these ground-living birds found in Australia and some Pacific Islands. One species in Tonga makes a nest of hot volcanic ash, which keeps its eggs warm. |
| SYCAMORE | Deciduous tree with doublewinged samaras in autumn; a naturalised species in Britain (8) |
| SPARROW | With two species in the UK, a finch-like bird known collectively as a host, quarrel or tribe (7) |
| SEAWEED | Conjured into a ship by Gwydion in The Mabinogion, marine algae with species in shades of brown, green or red, including carrageen, dulse, laver, oyster thief, peacock's tail, sargasso, tangle and wra |
| OSPREY | Bird of prey that used to be common in Mallorca but is now one of the most endangered species in Spain, a resident bird it can still be seen on the island (6) |
| KLINGON | One of a warlike species in Star Trek (7) |
| SPHERE | Round body of a species in this spot (6) |
| CHANTERELLE | Yellow fungus, a popular edible species in Europe (11) |
| MINK | Weasel-like mammal, a non-native species in the UK |
| COYPU | Rodent eradicated as a non-native species in the UK |
| PEPO | A cucurbit species in Europe (Poland) (4) |
| WATERVOLE | Ratty's species in The Wind in the Willows |
| LOBSTER | The most important commercial crustacean in Europe and the only extant species in the genus Nephrops (6,7) |
