Ok, lets keep it poisonous. Here some nice animal names:
Cascabel (Tropical rattlesnake: Crotalus durissus)
Large with diamond-shaped marks, two dark stripes on the neck and a rattle on the tail. Nocturnal and found in drier areas from eastern South America to Mexico. Aggressive. One of the worlds most dangerous!
Katipo (Latrodectus katipo)
The New Zealand relative of the Black Widow, found on beaches of North Island and the western coast of South Island. Lurks under driftwood, stones or well-sheltered plants. Can be fatal
Candiru (Vandellia cirrhosa)
Not much thicker than a pencil lead, a scaleless, parasitic catfish of South America. Said to enter the you-know-what openings of the body, their rear-pointing spines causing great pain.
Too wild? Ok, try these plant names:
Lobelia (Lobelia erinus)
Bell flower family. Native to South Africa and a garden ornament. Height 4-9. All parts are poisonous. Poison causing numbness, tingling in the mouth, abdominal pains and vertigo and affecting the heart. Can cause paralysis.
Croton (Codiaeum variegatum pictum)
Native to Pacific Islands and the Malay Peninsula. Also an ornamental in warm regions and a houseplant in temperate zones. Evergreen shrub with bright colored leaves. Height 4-7 All parts poisonous. Purgative action. Member of the Spurge family. Irritant poisons inducing abdominal pains, vomiting, nerve symptoms such as dilated pupils, headaches and, occasionally, convulsions. Sap causes blisters.
Laburnum (Laburnum anagyroides)
Native to south and central Europe and a common ornamental. Deciduous tree with pendulous bunches of yellow pea-like flowers. Height 5-10. All parts poisonous, including the roots, bark and wood. May be fatal. Causing a range of effects from loss of coordination and muscular movements, to double vision and deep sleep. Affects the nervous system, sometimes leading to death.
Lantana (Yellow sage: Lantana camara)
Native to the West Indies, naturalized throughout the tropics, a very common tropical ornamental and a houseplant. Evergreen shrub with domed flower heads in a wide color range, followed by black fruits. Height 18-39. Dangerously poisonous fruits. Irritant poison, causing burning pains in the throat and stomach, thirst, nausea, vomiting, fatigue and shock.
Mezereon (Daphne mezereum)
Native to Europe, Anatolia and Siberia, and a very common ornamental. Deciduous shrub with clusters of pale purple-pink to violet-red flowers on bare stems, followed by scarlet berries. Height 35-39. All parts a poisonous, especially the bark and berries. Can be fatal. Irritant poisons, causing burning pains in the throat and stomach, thirst, nausea, vomiting, fatigue and shock.
Still to negative? What about the following?
Malanga (Xanthosoma saggittifolium)
Native to the West Indies and an ornamental in southern US. Also a food plant. Tuberous-rooted perennial with large arum-like leaves. Height 30-48 All parts poisonous, especially the uncooked tubers.
Dasheen (Colocasia esculenta)
Native to Java, a garden ornamental and a food plant. It is a cormous-rooted parennial, with large arum-like leaves. Height 35-71. All parts poisonous if eaten raw, especially the corms.
Pangi (Pangium edule)
Native to the Malay Peninsula. Quick growing, spreading tropical tree, with large heart-shaped leave and reddish-brown, edible fruits. Height 20-25. Poisenous seeds, edible after cooking.
Well, that's nature,
Ralf