SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '18b4b130aa0d67ff73b7feea64560acb556223e995c2a5aafe5da50b17f62acd' 
  AND token = 'vJGRlRFGggRfJniJi7vBgWnJAYtxv3oc7IR5flSMxKk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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