SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0b235d9975c0410df4a4b292799a833d969ca69238aa162e0c0584627622f1c3' 
  AND token = 'R8Dw9MjaOA6jpoVucXiKy3ddeBiwZGvX5KAIOFwYqGU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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