SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a0c632b5c424d41f34fcc55a12992128760ae993e71f0d30aad521a79cfcb51' 
  AND token = 'FbHLgbtUWKpVDvN0GfsobS5m0QaTZbn8ynVWFpjO1EE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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