SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6a2d9192347fc6bc3406e332c0e86838f81d6ac48e36aac16e4ebacb78b56f93' 
  AND token = '8VzOkNitvj3Fgr/0mBLWdzj0htyYp0/g7lpuB9iwUJA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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