SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '47dabbbf6a09bfa33e2a0f93160ff41bf491ed40291b60443e6fbfc5dd8e1d79' 
  AND token = 'lmROLoEH/vrrfkbpGzElD7xO1g2o5IGHKGWUvlIJFkY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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