SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '5c86e9a746f9e7b71d88d9c4cefe393afa20fddb595c920ad34d03629d082d5e' 
  AND token = 'eaXv+/vd5y4ahdZIBuv0rgPJsR4dvivyPl7qwCIKcsg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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