Florida's always had a knack for unleashing heavy music on the unsuspecting world: Marilyn Manson, Limp-freaking-Bizkit, death metal. Now the suburban and rural areas of Tampa Bay crank out metalcore, also called screamo, a youth-driven subgenre developed in the hardcore punk underground.

In the late '90s, budding musicians took notice of the more metal-influenced emo bands coming to their towns from the Miami/Fort Lauderdale area (Poison the Well, Shai Hulud) and Jacksonville (Evergreen Terrace). Other bands were inspired when a brutal little group from Polk County, just inland from Tampa Bay, started to make waves with Christian and secular audiences alike.

"When we first started out, I was 15, 16, and I would listen to all these other bands and say I wanted to be in a band like that," says Chris Dudley, keyboardist and programmer for the Lakeland, Fla., metalcore act Underoath. "To know how much of an impact those bands have on what I'm doing, and then to have someone come up and tell me they're starting a band and they want to be like us, I just feel -- whoa."

Underoath's galvanizing effect on its local scene has been evident.

"When I moved here in '95, the only all-ages shows I knew at first were at [St. Petersburg's] State Theatre," says Tom Stevens, owner of Tampa Bay punk label Significant Records. "And when Underoath started playing, every time they played, they played to a bigger audience."

These days, Underoath is one of the most popular bands on kid-beloved Christian imprint Tooth & Nail. Though Underoath has begun exploring sonic turf outside of metalcore, neighboring Pinellas, Pasco and Polk counties remain littered with younger acolytes.

A MySpace.com search for bands self-described as screamo within 50 miles of Pinellas County ZIP code 33713 turns up 39 pages of sites -- at 10 bands per page. Some of those bands -- St. Petersburg's Anam Cara, Clearwater's Now Soldiers, Safety Harbor's Shed for You -- stand out. Many more are simply attempting to emulate their heroes, without the skills or character.

Tampa Bay musicians and fans like to carp that their hometown is five years behind major American cities in terms of sounds and trends. But thanks to the Internet, things seem to be looking the same all around the country.

"Oh yeah, it's totally everywhere," Dudley says of metalcore. "It's weird, because when kids are in their own city and don't get out a lot, they think things are only going on in their town."

So in this case, the Tampa-area metalcore swarm serves as an archetypal style-driven music scene -- a great band or two gets in on the ground floor of a nationally emerging sound and then captures the hearts and ambitions of a multitude of hopefuls. And chances are, a few years on, it'll serve as the archetypal death of a trend, as well.

"If you turn on MTV2, the style is pretty pervasive," Stevens says. "In five years it could be played out."

Dudley adds, "There are a lot of kids that are 18, 19, 20 that are hearing bands not much older than them doing something they like. But as those kids grow up and mature as musicians, they're gonna realize that you can't play the same song over and over again.

"I'm really interested to see where the music goes in the next five, six, 10 years. Even five years ago, music that had screaming in it, people were totally turned off by it. Now, it's perfectly acceptable."

For Your Ears (and Eyes)

• Underoath: They're Only Chasing Safety (Tooth & Nail)

• Now Soldiers: Sick World EP (Significant)

• www.underoath777.com; www.myspace.com/significantrecords; www.nowsoldiersdestroy.com; www.purevolume.com/anamcara