SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '55580f75cbfd1e3319a1f5689f42cb28dad156aa00b8d174878960264b97cfd6' 
  AND token = 'fqmUoPuW/GZf19Chc8mbeOGh3sQ6+5uIBRZfNKuKCe0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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