SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2289ce273ce7904aea448d9dc17ee4b5aa7b46e842f27097c5fdb00a31970097' 
  AND token = 'nByeqMj3TTz41IKtVZdY3Gdh4/MPWkbaqBoA/lbSf5M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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