SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed7ddbc6e1175225254ae460e49408d64c36c65f1037a788a23df4170763fdb5' 
  AND token = 'y8c6KazWKy9prpPG7TFEybmGbU8pPxdLSKi5kkhy3oU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}