SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'f1eb9382c65f36c8782f7dd3708272d22964be5cc7ec5682ee1e0f1bff7a732e' 
  AND token = 'qYSFrdVwb+wsf7IqG0ZXC9XoPAmuFgPWEyUFHkWi6hc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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