Most common here (all of them found at levels 31-34) are Skorupi, followed by Spoink (in Black 2) and Numel (in White 2) as well as Drifblim.  Less common are Trapinch, the evolved form of the game-specific pokemon (Grumpig and Camerupt), and at a one-in-twenty chance, Skarmory. 

Skorupi is a Poison/Bug pokemon that evolves at a late level 38 into Drapion.  Drapion is itself a bit of a curiosity, being one of the two Poison/Dark pokemon that exist.  Unlike Skuntank, Drapion has a fairly high speed and a top-rate Defense, while carrying only mediocre Special Defense and slightly more than decent Attack.  This wouldn’t make it too remarkable if not for its list of very solid attacks and the potential to learn Swords Dance via TM.  Even without Swords Dance, it has access to the curious move Acupressure, which randomly selects a boostable stat each time it is used and improves it by two stages- or 100% of its original value. 

Drifblim is an odd Ghost/Flying pokemon with a high Speed and massive Health value, often used to open battles for teams by dropping and Baton Passing Substitutes, though its Special Attack certainly isn’t anything to scoff at and its potential to use both Stockpile (which improves both Defenses) and Unberden (an Ability that doubles its speed when it consumes or drops its held item) can allow it to be both blisteringly fast and startlingly tough. 

Trapinch, while not terribly impressive overall (having only a strong Attack stat to recommend it) evolves eventually into the original Dragon/Ground pokemon, Flygon, which is a rather well-balanced Dragon-type that can perform offensively with either physical or special attacks.  While not as all-around awesome as Dragonite, the different typing of Flygon and its resulting access to a different pool of attack moves means that it holds its own very well with a slightly different use, stunting the efforts of opponents that don’t have Ice attacks and ruining virtually anything with a Ground weakness. 

Skarmory is one of the premier tanks of Pokemon, combining its Steel and Flying types to leave it weak to only Electric and Ground attacks.  Its Defense is top-notch, its Special Defense is quite all right, and its Speed is fairly good, though it leaves a lot lacking in its Attack stat.  Thankfully for those who use it, it has access to a wide array of hindering moves (including Spikes and Stealth Rock) and a few powerful attacks (most notably Brave Bird) that enable it to still mess up most of the things that it pops into battle to frustrate.