SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dc416b317951418dcc5b26bfe3bbc17ee8920aa82a525ad5903f5ee91af0b18f' 
  AND token = 'ORTk3l4IQntIGAO5Sd1Wqe1k5A7UMNtaWNGmcPt28Uw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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