SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60ad50f3951b6dd02d759d24eb95795609232152e466e9a6a0e6dd7d65357d98' 
  AND token = '6oIEDyi+x0a8PluL6RKeXzO0hugBA5pH0Ei3rKl9Q9A=' 
  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"
    }
  }
}