SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fa9a3682afd1c3fbc7ed541d66ee647ad678bd8c04baf7208992baef67b4fee8' 
  AND token = 'RT1joC316gLYutisDZsrUUauTo41cuQMKYW4emKzQfY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00487

JSON explain

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