Staghorn coral (Acropora cervicornis) Staghorns are some of the fastest growing and most exceptional reef building corals. The number of staghorn species is unknown at this time, but it is estimated that there could be as many as 400 of various shapes and colours. Small, soft-bodied coral polyps, related to jellies and anemones, are the reef builders. Nematocysts or stinging cells help them capture prey. These corals are found in warm, sunny, clear tropical waters. They have a unique symbiotic relationship with zooxanthellae (photosynthetic algae) living within their tissues. Considered environmentally sensitive, these corals are affected by pollution, silting, ocean warming and ocean acidification.