SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5f08a577c5edd7f094a35fd34732d598e915bfd5f6c6cdc60e608a07c63b1bd8' 
  AND token = 'Fz9BrtSOtGr2hKCHoiDWGlaHvyMDve3qq3QnQeXhsbE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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