SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '317ccfbf1a3d01bbd476e895ef89b875762e5bc85b929bc1ad8fe963f8af98c6' 
  AND token = '6ohPx/p9CYLH3LTLzOiTfAZ2hbpYhzYkbuAvyrNpMUw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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