SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3c96e67cbc0d90aa828d3516596d5f8a26b93d2033b7c3bde40cb94b0e74fd40' 
  AND token = 'JCYpHXa8xg/XGnhsZxG/raIb0zY1npYKAJnVCLwKt6w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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