SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c2aa2f6151567e2d05a09c5ddb320d89caa2f4d9e359a888abb182f60b6a827a' 
  AND token = 'ATXR2lnXwrkYM2c5GxehktPFWY7FQLYTNIm2H3C+flU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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