SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0b0c24a3ddd32c278a230a59ccd59b096c15f4a7544b7de8b3bd2f1fd1a28532' 
  AND token = 'z+JxJtSHO8VEjiE7PR+w62jGK7gv4XyYhbEDSWq0kr0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00067

JSON explain

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