EDIT

    static public String concat(CharSequence separator, String... strings){

				 Set<HybridRelationship> existingRelations = new HashSet<>();

				 Set<HybridRelationship> notToBeDeleted = new HashSet<>();

				 firstNameString = firstNameString.trim();

				 secondNameString = secondNameString.trim();

				 INonViralName firstName = this.parseFullName(firstNameString, code, rank);

				 if (secondNameString.matches(abbrevHybridSecondPart)){

				     secondNameString = extendSecondHybridPart(firstName, secondNameString);

				 }

				 INonViralName secondName = this.parseFullName(secondNameString, code, rank);

				 if (firstRank == null || (secondRank != null && firstRank.isHigher(secondRank))){

     * @param firstName

     * @param secondNameString

     * @return

     */

    private String extendSecondHybridPart(INonViralName firstName, String secondNameString) {

        //first letter of genus given

        if (secondNameString.matches("^" + abbrevHybridGenus + ".*")){

            if (StringUtils.isNotBlank(firstName.getGenusOrUninomial())){

                if (secondNameString.substring(0,1).equals(firstName.getGenusOrUninomial().substring(0, 1))){

                    secondNameString = secondNameString.replaceAll("^" + abbrevHybridGenus, firstName.getGenusOrUninomial() + " ");

                }

            }

        }else if (secondNameString.matches(abbrevHybridSecondPartOnlyInfraSpecies)){

            secondNameString = CdmUtils.concat(" " , firstName.getGenusOrUninomial(), firstName.getSpecificEpithet(), secondNameString);

        }else if (true){  //there will be further alternatives in future maybe

            secondNameString = CdmUtils.concat(" " , firstName.getGenusOrUninomial(), secondNameString);

        }

        return secondNameString;

    }

    /**

    protected static String infraSpeciesMarkerNoNotho = "(subsp\\.|convar\\.|var\\.|subvar\\.|f\\.|subf\\.|f\\.\\ssp\\.|f\\.spec\\.|f\\.sp\\.|\\[unranked\\]|tax\\." + fWs + "infrasp\\.)";

    protected static String infraSpeciesMarker = "(n|notho)?" + infraSpeciesMarkerNoNotho;

    protected static String abbrevHybridGenus = "([A-Z](\\.\\s*|\\s+))";

    protected static String abbrevHybridSecondPartWithSpecies = abbrevHybridGenus + "?" + nonCapitalEpiWord + "(" + oWs + infraSpeciesMarkerNoNotho + oWs + nonCapitalEpiWord + ")?";  //#5983 first step but still to strict

    protected static String abbrevHybridSecondPartOnlyInfraSpecies = infraSpeciesMarkerNoNotho + oWs + nonCapitalEpiWord;

    protected static String abbrevHybridSecondPart = "(" + abbrevHybridSecondPartWithSpecies + "|" + abbrevHybridSecondPartOnlyInfraSpecies + ")";

    protected static String hybridSecondPart = "(" + anyFullName  + "|" +  anyBotanicName + "|" + anyZooName + "|" + abbrevHybridSecondPart + ")";

    protected static String hybridFullName = "(" + anyFullName  + "|" +  anyBotanicName + "|" + anyZooName + ")" + hybridFormularSeparator + hybridSecondPart ;

        //hybrids with authors  //happens but questionable

        //abbreviated genus hybrid formula #6410 / #5983

        String nameStr = "Nepenthes mirabilis \u00D7 N. alata";

        name1 = parser.parseFullName(nameStr, botanicCode, null);

        assertTrue("Name must have hybrid formula bit set", name1.isHybridFormula());

        assertEquals("Name must have 2 hybrid parents", 2, name1.getHybridChildRelations().size());

        //could also be N. or no genus at all, depends on formatter

        assertEquals("Title cache must be correct", "Nepenthes mirabilis \u00D7 Nepenthes alata", name1.getTitleCache());

        orderedRels = name1.getOrderedChildRelationships();

        assertEquals("Name must have 2 hybrid parents in ordered list", 2, orderedRels.size());

        firstParent = orderedRels.get(0).getParentName();

        //to be discussed as usually they should be ordered alphabetically

        assertEquals("Name must have Nepenthes mirabilis as first hybrid parent", "Nepenthes mirabilis", firstParent.getTitleCache());

        secondParent = orderedRels.get(1).getParentName();

        assertEquals("Name must have Nepenthes alata as second hybrid parent", "Nepenthes alata", secondParent.getTitleCache());

        assertEquals("Hybrid name must have the lower rank ('species') as rank", Rank.SPECIES(), name1.getRank());

        //missing genus hybrid formula #5983

        nameStr = "Nepenthes mirabilis \u00D7 alata";

        name1 = parser.parseFullName(nameStr, botanicCode, null);

        assertTrue("Name must have hybrid formula bit set", name1.isHybridFormula());

        assertEquals("Name must have 2 hybrid parents", 2, name1.getHybridChildRelations().size());

        //could also be N. or no genus at all, depends on formatter

        assertEquals("Title cache must be correct", "Nepenthes mirabilis \u00D7 Nepenthes alata", name1.getTitleCache());

        orderedRels = name1.getOrderedChildRelationships();

        assertEquals("Name must have 2 hybrid parents in ordered list", 2, orderedRels.size());

        firstParent = orderedRels.get(0).getParentName();

        //to be discussed as usually they should be ordered alphabetically

        assertEquals("Name must have Nepenthes mirabilis as first hybrid parent", "Nepenthes mirabilis", firstParent.getTitleCache());

        secondParent = orderedRels.get(1).getParentName();

        assertEquals("Name must have Nepenthes alata as second hybrid parent", "Nepenthes alata", secondParent.getTitleCache());

        assertEquals("Hybrid name must have the lower rank ('species') as rank", Rank.SPECIES(), name1.getRank());

        //#5983 subsp. with species and missing genus

        nameStr = "Orchis coriophora subsp. fragrans \u00D7 sancta";

        name1 = parser.parseFullName(nameStr, botanicCode, null);

        assertTrue("Name must have hybrid formula bit set", name1.isHybridFormula());

        assertEquals("Name must have 2 hybrid parents", 2, name1.getHybridChildRelations().size());

        //could also be N. or no genus at all, depends on formatter

        assertEquals("Title cache must be correct", "Orchis coriophora subsp. fragrans \u00D7 Orchis sancta", name1.getTitleCache());

        orderedRels = name1.getOrderedChildRelationships();

        assertEquals("Name must have 2 hybrid parents in ordered list", 2, orderedRels.size());

        firstParent = orderedRels.get(0).getParentName();

        assertEquals("Name must have Orchis coriophora subsp. fragrans as first hybrid parent", "Orchis coriophora subsp. fragrans", firstParent.getTitleCache());

        secondParent = orderedRels.get(1).getParentName();

        assertEquals("Name must have Orchis sancta as second hybrid parent", "Orchis sancta", secondParent.getTitleCache());

        assertEquals("Hybrid name must have the lower rank ('subspecies') as rank", Rank.SUBSPECIES(), name1.getRank());

        //2 subspecies with missing genus part #5983

        nameStr = "Orchis morio subsp. syriaca \u00D7 papilionacea subsp. schirvanica";

        name1 = parser.parseFullName(nameStr, botanicCode, null);

        assertTrue("Name must have hybrid formula bit set", name1.isHybridFormula());

        assertEquals("Name must have 2 hybrid parents", 2, name1.getHybridChildRelations().size());

        //could also be N. or no genus at all, depends on formatter

        assertEquals("Title cache must be correct", "Orchis morio subsp. syriaca \u00D7 Orchis papilionacea subsp. schirvanica", name1.getTitleCache());

        orderedRels = name1.getOrderedChildRelationships();

        assertEquals("Name must have 2 hybrid parents in ordered list", 2, orderedRels.size());

        firstParent = orderedRels.get(0).getParentName();

        assertEquals("Name must have Orchis morio subsp. syriaca as first hybrid parent", "Orchis morio subsp. syriaca", firstParent.getTitleCache());

        secondParent = orderedRels.get(1).getParentName();

        assertEquals("Name must have Orchis papilionacea subsp. schirvanica as second hybrid parent", "Orchis papilionacea subsp. schirvanica", secondParent.getTitleCache());

        assertEquals("Hybrid name must have the lower rank ('subspecies') as rank", Rank.SUBSPECIES(), name1.getRank());

        //subspecies and variety with missing genus part

        nameStr = "Orchis morio subsp. syriaca \u00D7 papilionacea var. schirvanica";

        name1 = parser.parseFullName(nameStr, botanicCode, null);

        assertTrue("Name must have hybrid formula bit set", name1.isHybridFormula());

        assertEquals("Name must have 2 hybrid parents", 2, name1.getHybridChildRelations().size());

        //could also be N. or no genus at all, depends on formatter

        assertEquals("Title cache must be correct", "Orchis morio subsp. syriaca \u00D7 Orchis papilionacea var. schirvanica", name1.getTitleCache());

        orderedRels = name1.getOrderedChildRelationships();

        assertEquals("Name must have 2 hybrid parents in ordered list", 2, orderedRels.size());

        firstParent = orderedRels.get(0).getParentName();

        assertEquals("Name must have Orchis morio subsp. syriaca as first hybrid parent", "Orchis morio subsp. syriaca", firstParent.getTitleCache());

        secondParent = orderedRels.get(1).getParentName();

        assertEquals("Name must have Orchis papilionacea var. schirvanica as second hybrid parent", "Orchis papilionacea var. schirvanica", secondParent.getTitleCache());

        assertEquals("Hybrid name must have the lower rank ('variety') as rank", Rank.VARIETY(), name1.getRank());

        //2 subspecies with missing genus and species part #5983

        nameStr = "Orchis morio subsp. syriaca \u00D7 subsp. schirvanica";

        name1 = parser.parseFullName(nameStr, botanicCode, null);

        assertTrue("Name must have hybrid formula bit set", name1.isHybridFormula());

        assertEquals("Name must have 2 hybrid parents", 2, name1.getHybridChildRelations().size());

        //could also be N. or no genus at all, depends on formatter

        assertEquals("Title cache must be correct", "Orchis morio subsp. syriaca \u00D7 Orchis morio subsp. schirvanica", name1.getTitleCache());

        orderedRels = name1.getOrderedChildRelationships();

        assertEquals("Name must have 2 hybrid parents in ordered list", 2, orderedRels.size());

        firstParent = orderedRels.get(0).getParentName();

        assertEquals("Name must have Orchis morio subsp. syriaca as first hybrid parent", "Orchis morio subsp. syriaca", firstParent.getTitleCache());

        secondParent = orderedRels.get(1).getParentName();

        assertEquals("Name must have Orchis morio subsp. schirvanica as second hybrid parent", "Orchis morio subsp. schirvanica", secondParent.getTitleCache());

        assertEquals("Hybrid name must have the lower rank ('subspecies') as rank", Rank.SUBSPECIES(), name1.getRank());

        //subspecies and variety with missing genus and species part #5983

        nameStr = "Orchis morio subsp. syriaca \u00D7 var. schirvanica";

        name1 = parser.parseFullName(nameStr, botanicCode, null);

        assertTrue("Name must have hybrid formula bit set", name1.isHybridFormula());

        assertEquals("Name must have 2 hybrid parents", 2, name1.getHybridChildRelations().size());

        //could also be N. or no genus at all, depends on formatter

        assertEquals("Title cache must be correct", "Orchis morio subsp. syriaca \u00D7 Orchis morio var. schirvanica", name1.getTitleCache());

        orderedRels = name1.getOrderedChildRelationships();

        assertEquals("Name must have 2 hybrid parents in ordered list", 2, orderedRels.size());

        firstParent = orderedRels.get(0).getParentName();

        assertEquals("Name must have Orchis morio subsp. syriaca as first hybrid parent", "Orchis morio subsp. syriaca", firstParent.getTitleCache());

        secondParent = orderedRels.get(1).getParentName();

        assertEquals("Name must have Orchis morio subsp. schirvanica as second hybrid parent", "Orchis morio var. schirvanica", secondParent.getTitleCache());

        assertEquals("Hybrid name must have the lower rank ('variety') as rank", Rank.VARIETY(), name1.getRank());

//    @Test

//    public final void testTemp(){

////        String nalata = "N. alata";

////        if (! nalata.matches(NonViralNameParserImplRegExBase.abbrevHybridSecondPart)){

////            throw new RuntimeException();

////        }

//

//        //abbreviated hybrid formula #6410

//        String nameStr = "Orchis morio subsp. syriaca \u00D7 papilionacea subsp. schirvanica";

//        INonViralName name1 = parser.parseFullName(nameStr, botanicCode, null);

//        assertTrue("Name must have hybrid formula bit set", name1.isHybridFormula());

//        assertEquals("Name must have 2 hybrid parents", 2, name1.getHybridChildRelations().size());

//        //could also be N. or no genus at all, depends on formatter

//        assertEquals("Title cache must be correct", "Orchis morio subsp. syriaca \u00D7 Orchis papilionacea subsp. schirvanica", name1.getTitleCache());

//    }