SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd817156e8a966bb482d7ee25517677bfcc57411ca1d041cc5b8ab30fd58e280e' 
  AND token = 'iFgpU6Xo7hVZ/WzbZGuFIy5oLb4WgZCwqugq3NrQnCU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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