SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'ab8aaf2938ed12981357ebf693700ac8d6e4fff0161cb957914e166e4b02e5d5' 
  AND token = 'zrZK91KWfMOz2DnrKzqHucbqZbKPO+W+fdTsBDhuOLI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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