SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '70f9e7111b789cb19eb3d512546a117f58aa8b1344dcf5972b44aa1aa1a1db4f' 
  AND token = 'hgC5ykMnzC9/twtRoruLytKZ/qmQ9aw45bw2UyjaOzs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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