Spear phishing

Spear phishing is a phishing message written for one person, using real details about them.

Ordinary phishing goes to a million people and hopes. This goes to you, mentions the project you are actually working on, names your actual manager, and arrives at a plausible moment. The advice that works against bulk phishing, look for the odd spelling and the strange address, does much less here, because somebody has taken the time to get those right. What still works is verifying through a route you chose rather than one the message gave you.