Exerpts from:
United States Code Annotated Currentness. Title 16. Conservation. Chapter 53. Control of Illegally Taken Fish and Wildlife.
Citation: 16 USC 3371 - 3378
Citation: 95 Stat. 1073
Summary: The Lacey Act provides that it is unlawful for any person to import, export, transport, sell, receive, acquire, or purchase any fish or wildlife or plant taken, possessed, transported, or sold in violation of any law, treaty, or regulation of the United States or in violation of any Indian tribal law whether in interstate or foreign commerce.
(a) The term “fish or wildlife” means any wild animal, whether alive or dead, including without limitation any wild mammal, bird, reptile, amphibian, fish, mollusk, crustacean, arthropod, coelenterate, or other invertebrate, whether or not bred, hatched, or born in captivity, and includes any part, product, egg, or offspring thereof.
(b) The term “import” means to land on, bring into, or introduce into, any place subject to the jurisdiction of the United States, whether or not such landing, bringing, or introduction constitutes an importation within the meaning of the customs laws of the United States.
(1) Taken
The term “taken” means captured, killed, or collected and, with respect to a plant, also means harvested, cut, logged, or removed.
(2) Taking
The term “taking” means the act by which fish, wildlife, or plants are taken.
(k) The term “transport” means to move, convey, carry, or ship by any means, or to deliver or receive for the purpose of movement, conveyance, carriage, or shipment.
It is unlawful for any person--
(1) to import, export, transport, sell, receive, acquire, or purchase any fish or wildlife or plant taken, possessed, transported, or sold in violation of any law, treaty, or regulation of the United States or in violation of any Indian tribal law;
(2) to import, export, transport, sell, receive, acquire, or purchase in interstate or foreign commerce--
(A) any fish or wildlife taken, possessed, transported, or sold in violation of any law or regulation of any State or in violation of any foreign law;
(b) Marking offenses
It is unlawful for any person to import, export, or transport in interstate commerce any container or package containing any fish or wildlife unless the container or package has previously been plainly marked, labeled, or tagged in accordance with the regulations issued pursuant to paragraph (2) of section 3376(a) of this title.
So, Here is the deal:
The Lacey Act makes it a federal offense to posses, sell or ship ANY plant or animal that is illegally collected from anywhere on the planet in the United States and it's territories. The law also applies to any captive bred progeny of illegally collected plants or animals. It is also illegal to mislabel or otherwise misrepresent the plant or animal as other for the purpose of sale and shipping. There are exceptions, permits and the like are available in some cases. The key words here are "illegally taken".
I will use Ambystoma texanum here in Nebraska as an example: A. texanum is a protected species Nebraska, my state of residence. If I caught some and sold and shipped them to you, not only would I be violating Nebraska Law, I would be violating Federal Law. The Lacey Act re-enforces applicable state, territory and tribal laws.
Now, If you caught some A. texanum in a state it is legal to do so and sold and shipped them to me, this would be legal federally only if you included a certified affidavit stating that the source of the animal is NOT Nebraska and it was legally collected with Fishing Permit blah-blah-blah (as this fulfills the Nebraska Law).
The shipping box would have to be clearly labeled Ambystoma texanum. We would both have to maintain the affidavit on file for the life span of the animal AND its progeny to comply with Nebraska Law and the Lacey Act as the Act re-enforces the state law.
The Lacy Act's applicability varies greatly based on all the other amphibian related laws, and varies from state to state!
The current revision of the act adds in applicability to logging and timber products.