SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e9abbcb5edfa89fadc8abb4360b9eb40a900765688b6419898f41397df3ce091' 
  AND token = 'FaWR/LwYxdcqzZvRT761c8Tt0CgjmLxuZU6r4yvVMMY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}