SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae63d9ab4dcc9824372669d5136946a4ae41941686a554e85ef2f340fe30a32a' 
  AND token = 'l0wTz/NtqrGhw8aWpK9CBTRbtLgFvEUAhX3c8DWd66A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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