SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c579a1059dc1ef6f87310da5176fc49f49b007ef2a8bee48cd34c9334a8c7573' 
  AND token = 'LZCYv311XILyYSXK+MIu+yg8wqFKzf9F4uyZE+PT94g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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