SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '958c79156a3139463ea5f50192b7ade28d069b3bbdd460f6c433ec29b69b560b' 
  AND token = 'v2B1yFKk8/Klg+oJqayazksNWcwdJ94rq57M8G9Qqjo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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