Are there any Pokémon that lose overall base stats when they evolve?

Most Pokémon become more powerful when they evolve, gaining a higher base stat amount in all their stats (HP, attack, defense, special attack, special defense and speed), and a higher base stat total. Are there any Pokémon in any of the mainline games that, after evolving, instead have an equal or lower base stat total as their evolution than as their pre-evolution?

Solution 1:

A Pokémon's base stat total not increasing after evolution happens in only two cases:

• Scyther evolving into Scizor, which trades 40 base Speed for 20 base Attack and 20 base Defense. Scizor has the same base stat total as Scyther, making Scizor the only "side evolution" in Pokémon.
• Nincada "evolving" into Shedinja, which trades 30 base HP and 45 base Defense for 45 base Attack. Thanks to Shedinja's Wonder Guard ability and its fixed 1 HP, its Defense and Special Defense stats are essentially not used. Shedinja still loses 30 base stat total compared to Nincada, however