SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '00452847eeaeee34a57fdf3173a023b91c60ef95ff17f01d78b344dc86c811ee' 
  AND token = 'K/VhtZjkH5J9u7oz4eLXgmhafmy6v56xxt2RUOYG3j8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}