SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aea3b7963f72ce6b59ecfcbd27eb0219065bf9454b573c13ae74eb2f230696f1' 
  AND token = 'F8mX6cfiY3mMo5QYxY/W1pGVT4MrjPyxM/pOQFn6XmM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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