SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '88010fc5d5e68cc1c437afbc4e9f6eb898e519d62b518018d56de65e7e95eb4f' 
  AND token = 'IwpUJFAUacl6DMT6dCbNvTDcGKIU5Fh1eMFq45MQt1o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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