SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5dbaf6f562ec896e477ec48aa17be23bd7b81861c38b39e6d68eb1dc46d98418' 
  AND token = 'TxCCyesRi5qjD3Fc2Gl/GH12BTRMiR8hVLbcZ+yHIRU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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