SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7eaf8958946ced4c4edd2ef1e9f5bb5e3a583f8be1e084f644f875933ab87931' 
  AND token = 'OKJ1DeGH2W6/PtEjrbDCT/PU9cHbRzxHq4bQ9BiWZcA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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