SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'd8ceffd3be0c17dae6fb12cfc14e4f43076ac94b7e956d793fe0928772c2544a' 
  AND token = 'x9xIy/7dovcOVDUHqQ+CCWMi+QZ1lkTsy2qH4yGNebI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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