SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '88d0cedd8423443992b44f39a8dc2f5a6d04a1e113fb15d97d994bacca7da9de' 
  AND token = 'MdJLJLwE2V8yM6GZBQpCUFvcsZB9v6IKlVJ8Ym+n6bg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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