For example: Gyarados is mainly a physical attacker, but its Sp. Def is higher than its regular Defense. Similarly, Magnezone is mainly a special attacker, but its regular Defense is higher than its Sp. Def.
What other Pokemon have a similar stat distribution?
Mega Venusaur Def>SpD Mega Blastoise Def>SpD Beedrill And Mega Beedrill SpD>Def Raticate SpD>Def Arbok SpD>Def Dugtrio & Alolan Dugtrio SpD>Def Persian SpD>Def (Regular Only) Primeape SpD>Def Machamp SpD>Def Victreebel SpD>Def Rapidash SpD>Def Slowbro And Mega Slowbro Def>SpD (Mega has a big differnce btw) Farfetch'd SpD>Def Muk And Alolan Muk SpD>Def Hitmonlee SpD>Def Hitmonchan SpD>Def Seaking SpD>Def Gyarados and Mega Gyarados SpD>Def Flareon SpD>Def Lord Helix (Omastar) Def>SpD Aerodactyl And Mega Aerodactyl SpD>Def Moltres Def>SpD Dragonite SpD>Def Umbreon SpD>Def Heracross SpD>Def (Regular Only) Magcargo Def>SpD Stantler SpD>Def Hitmontop SpD>Def Ho-Oh SpD>Def Pelipper Def>SpD Ninjask SpD>Def Volbeat SpD>Def Kecleon SpD>Def Gorebyss Def>SpD Lopunny and Mega Lopunny SpD>Def Chatot Def>SpD Weavile SpD>Def Magnezone Def>SpD Tangrowth Def>SpD Electivire SpD>Def Yanmega Def>SpD Glaceon Def>SpD Gallade and Mega Gallade SpD>Def Dialga Def>SpD Samurott Def>SpD Excadrill SpD>Def Whimsicott Def>SpD Cofagrigus Def>SpD Pyroar Def>SpD Gogoat SpD>Def Furfrou SpD>Def (However Fur Coat balances it) Slurpuff Def>SpD Trevenant SpD>Def Volcanion Def>SpD Decidueye SpD>Def Vikavolt Def>SpD Araquanid SpD>Def Palossand Def>SpD Komala SpD>Def Turtonator Def>SpD Togedemaru SpD>Def Mimikyu SpD>Def Celesteela Def>SpD Necrozma (Regular) Def>SpD Marshadow SpD>Def Zeraora (Its Not Released Yet) SpD>Def
Btw this took me almost a hour to make so I hope you would benefit from it. And Note: This is only fully evolved Pokemon and its also order from first to last dex number. Peace!