SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9ccd47118e23f8f234007c00e251a20c5b30c626c5d23502271ff4d6a7b872ff' 
  AND token = 'kgBGLbauRGA+6ekGUBnSWOtPsi218PmdVkpIlqFz3Gc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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