SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7496ae6eb2f134c1a356759cf3890339efc733955305bc0881c8590c6be570e6' 
  AND token = 'FpJD26fbpSdGip/p4/oZyEMlRLhR8eGa2VTkUBntN5c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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