The mostly cavernicolous millipede genus Stygiiulus Verhoeff, 1929, stat. nov.: taxonomy, distribution and phylogenetic relationships (Diplopoda, Julida, Julidae) Author Vagalinski, Boyan CF6A5691-5C32-4CFF-9EB6-045DEB16F289 Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin Street, 1113, Sofia, Bulgaria. boyanv84@gmail.com Author Borissov, Simeon C035E1AC-D4FB-4A3F-8B38-5D38A9665E88 Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin Street, 1113, Sofia, Bulgaria. borissovsb@gmail.com Author Bobeva, Aneliya 0F4EA315-46BE-49AC-8FB4-CF710C5B2451 Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 2 Gagarin Street, 1113, Sofia, Bulgaria. aneliabobeva@gmail.com Author Canciani, Giacomo 4BB21FD2-15C8-44BD-907A-4498D7D02A15 Jamarski Klub Kraški Krti / G. S. Talpe del Carso, loc. San Michele del Carso / Vrh, I- 34070 Savogna d’Isonzo (GO), Italy. & Associazione Speleologica Forum Julii Speleo, Via Carraria 99, I- 33043 Cividale del Friuli (UD), Italy. giacomo.canciani90@gmail.com Author Antić, Dragan Ž. 2368C980-2042-4137-998D-8C91E4337185 University of Belgrade - Faculty of Biology, Institute of Zoology, Studentski Trg 16, 11000 Belgrade, Serbia. & Serbian Biospeleological Society, Trg Dositeja Obradovića 2, 21000 Novi Sad, Serbia. dragan.antic@bio.bg.ac.rs text European Journal of Taxonomy 2022 2022-02-28 798 30 69 http://dx.doi.org/10.5852/ejt.2022.798.1669 journal article 20422 10.5852/ejt.2022.798.1669 31fec661-5dac-4626-856d-4ba4680efee7 2118-9773 6323002 50692D26-A41C-4F85-B207-A6747FD07470 Typhloiulus ( Typhloiulus ) strictus (Latzel, 1882) Fig. 11H Material examined BULGARIA • 1 ♀ ; Lovech District , Kunino , at the entrance of Samuilitsa 2 Cave ; 30 Oct. 2020 ; B. Vagalinski leg.; under large stones with moss ; IBER . Descriptive notes Vulva ( Fig. 11H ). Slender, of nearly equal width in both the sagittal and the transverse planes, mostly symmetric; bursa with a rather broad and deep median cleft; each valve with up to ten, mostly vertically arranged setae; several setae in a vertical row on each side sclerite; operculum (op) with broadly rounded, somewhat coarsed, apical margin, exceeding bursa by nearly 1 ⁄ 3 of total height of vulva, distally with a few long setae each side. Receptaculum seminis consisting of a narrow, partly twisted posterior tube (pt) ending in a medium-sized piriform/lemon-shaped ampula (pa), and a much broader, mostly straight anterior tube (at), not forming an ampulla at bottom. Phylogeny A total of 37 taxa (1 outgroup) were included in the analyses. The 28S rRNA dataset included 499 bp and 20 gaps. Of these there were 61 variable and 41 parsimony-informative sites. The 16S rRNA dataset included 488 bp with 69 gaps, 350 variable and 295 parsimony-informative sites. Maximum likelihood and Bayesian inference analyses showed similar topology, but ML did not obtain strong bootstrap support. The two matrices, analyzed separately, resulted in similar topology but did not resolve deeper nodes (trees not shown). The best resolution was shown by the BI tree, inferred from the concatenated 16S rRNA+28S rRNA dataset ( Fig. 12 ). Our analyses reproduced the results of previous studies and show agreement with published trees (see Enghoff et al. 2011 , 2013 ; Makarov et al. 2017 ). The deep nodes did not receive strong support, although some monophyletic clades were strongly supported.These include the tribes Brachyiulini and Pachyiulini, as well as the clade Leucogeorgia + ( Pteridoiulus + Heteroiulus ) (see Enghoff et al. 2013 ). Members of the dubious tribe Typhloiulini formed a strongly supported monophyletic clade with the following topology: Rhodopotyphlus mitovi + (( Typhloiulus orpheus + ( T. lobifer + T. gracilis ))+ ( T. bureschi + T. georgievi + ( T. nevoi + ( Serboiulus deelemani + Serboiulus lucifugus )))). The newly represented species Stygiiulus fimbriatus comb. et stat. nov. grouped with Xestoiulus imbecillus ( Latzel, 1884 ) , the two forming a sister clade to the monophyletic (julinine/leptoiulinine) group: Ophyiulus pilosus + ( Pacifiiulus amurensis + ( Leptoiulus trilineatus + ( Leptoiulus proximus + Julus scandinavius ))).