SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a41bd26158a8fe94b93be8393d0c98781e661c923df65fa145fb8d9b8fd03c36' 
  AND token = 'hq+r1G5IUa7vRZroZkK22XCFvQy/w44GMUjMWmwTnwY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}