SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ae785f01386d5e409b6dba41b6664434c01ef24a145be752dc5ca606be69244' 
  AND token = 'ANezgfXIdbUTpm8h0NmougW2pqLh+CzAKblYGfFShto=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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