SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '23a4ab3a2d8cb97fb3122c61a7d1fd2af346d700d49e24d55f463d3d8ed4be69' 
  AND token = 'Gx85Vb/zbBe8Dp87W0oho6m6j0Yaw1Ji/VLkT+AETB4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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