SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '4fb0062a524f8833a8a398d5158729a90b1a85af69b165648e78556176195a0f' 
  AND token = 'kwbd7V8kpglPveeBKMlHf2PMjc4q8OGRGI/BL/rPFDs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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