SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c3d88ae1d9606f76064e3a4805c59d1a4ed563642992e8835c0a2b23f859dd4b' 
  AND token = '80xwvH4gFTgQt9YBVa/TYBCioO1icsH7KbMk4hKeia4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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