SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c67ebe8b7e13255609e23b7459890411d03f99ac284d7af475e95c389ded8ad2' 
  AND token = 'uJ98Und5Bs2Anwqa1X9WEC0543bqy6h5aKumneax5O0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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