SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4b2add2967872b61f9ccdd8071876e5c6ab3d275da6b2aa7751fc07564082181' 
  AND token = '5ONRH//MMHPd635WQ4wCX0Fw9wDnFNr1ZiX9MXlKsTU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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