SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2ab8b408dc32760ec8e6fd5e929c5d2487aad78a9bd3f755d8d5a5888135614d' 
  AND token = 'fHV21PtFCmWqcfzMXDtGTn4iI7lLP+xRYJcY8Q9WXSU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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