Incorrect spelling, explanation: the most common way of creating regular past simple/past participle forms (and also the adjective participles) is adding a specific suffix (-d or -ed) to an unchanged root (the verb). It’s worth remembering that sometimes we must do one other thing: double the last consonant of the root when there is a single (and stressed) vowel before the last consonant in a word. That is the reason why this word should be spelled as spotted, not spoted.

Correct spelling, explanation: the word spotted is a derivative of the verb spot. As you can see, it contains a double -t letter. If you’re wondering why, here’s the crucial rule: we need to double the final letter when a one-syllable verb ends in consonant + vowel + consonant. Many English users tend to forget about this principle and spell this kind of verb with just one consonant. Spoted is not correct.

Definition of spotted:
adjective, marked or decorated with spots
The Dalmatian is a popular breed of dog known for its spotted coat.
The spotted lanternfly is an invasive insect species that is causing damage to crops and trees in many parts of the United States.

Collocations with spotted:
Some most commonly used collocations include:
1. Spotted cow: a type of beer brewed in Wisconsin, United States.
The Spotted Cow is a popular local beer in Wisconsin.
2. Spotted dick: a traditional British dessert made with suet and dried fruit.
Spotted dick is often served with custard or cream.