SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7bfc60c98259e59ff26b798fff1b6b80d5ccd3f94cf5bb160543a013c045e314' 
  AND token = 'fMoB5kpRiW+zVT53d1Gx/UpNx1BiyWTYej3bxktxEZ0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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