SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fb312e3d6dad31d8bdc84a42887856171145dc7765b52a1865868e1e95dc013d' 
  AND token = '1gojzpJCkuB4dQSmFjtO6nuhaA5T7hOXZF2yo8M3pm8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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