Avicennia marina vs blackwood

Avicennia marina and blackwood both are nouns.

Word	Noun	Adjective	Verb	Adverb
Avicennia marina	Yes	No	No	No
blackwood	Yes	No	No	No

As nouns, blackwood is a hypernym of Avicennia marina; that is, blackwood is a word with a broader meaning than Avicennia marina:

Avicennia marina: a mangrove of the West Indies and the southern Florida coast; occurs in dense thickets and has numerous short roots that bend up from the ground
blackwood: any of several hardwood trees yielding very dark-colored wood

Other hypernyms of Avicennia marina include blackwood tree.

Avicennia marina (noun)	blackwood (noun)
a mangrove of the West Indies and the southern Florida coast; occurs in dense thickets and has numerous short roots that bend up from the ground	any of several hardwood trees yielding very dark-colored wood
	very dark wood of any of several blackwood trees