SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a8cc371f4d89cf0f6d2f2d4091d41ca57c6c5df37aa202a69b1f3caf837bd1b5' 
  AND token = 'Uj1GkFur+NZO9d2EHUMGF9yRRIrm6BuvSzBuGzuCViI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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