SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '01f7f7bc7cbd8a8fa3f2de245cba199457c6671c773987b57509b3d13f1e866a' 
  AND token = '/HOQuSYiNroNiKLqDJzfJkLIgwRQJTdZm2C6oK/lnCU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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