Balkanopetalum bulgaricum, Stoev & Enghoff, 2003

Stoev, Pavel & Enghoff, Henrik, 2003, Systematics, phylogeny and biogeography of genus Balkanopetalum Verhoeff, 1926 (Diplopoda: Callipodida: Schizopetalidae), Zootaxa 272 (1), pp. 1-26 : 14-16

Balkanopetalum bulgaricum sp. n.

Figs 13­15 .

Material examined (all from Bulgaria): Holotype: adult M; 54 pleurotergites, length 57 mm, width ca. 4 mm; NMNH­Sofia, Callipodida collection; southern slopes of the Pirin Mts. , Gotse Delchev District , Goleshevo Village, Starshelitsa Cave, 1,000 m, 17.04.1992, B. Petrov leg. — Paratypes: 1 M, 1F, 2 subad., 2 juveniles, Goleshevo Village , Starshelitsa Cave, 29.11.1992, B. Petrov leg. ; 1F, 3 subad (1F, 1 subad., ZMUC), same locality, 02.05.1994, B. Petrov leg. ; 1 M, Slavyanka (= Orvilos ) Mts., Tsarev Peak, 08.06.1936, P. Drensky leg.

Etymology. Self­evident.

Description. Length ca. 57 mm. Width ca. 4 mm., 53­54 body pleurotergites.

Head and anterior pleurotergites are dark brown, speckled with irregular yellow spots. Mid body pleurotergites paler brown­yellowish, posterior pleurotergites ­ whitish­grayish.

Head concavity in males hairless; numerous bristles forming an irregular row between the concavity and the labrum.

Collum with dark brown posterior stripe, extending anteriad in the middle.

Antennomeres all dark brown.

Chaetotaxy see Table 5.

Male gonopods: coxa with two anterior and one subanterior coxal processes, corresponding to the two­tined anterior process seen in congeners, and the subanterior process in armatum ; the subanterior process almost twice longer than the other two, apically unevenly rounded. Posterior coxal process as long as the main stem of the femoroid, apically bifurcate, distalmost branch shorter than the other. Femoroid elongate, apically curving anteriad, tip shallowly bifurcate. Distal process long, sigmoid, apically with two tines. Ovoid plate is rectangular, dark, reaching to about the middle of the femoroid. Solenomerite bifid, the middle part of its stem bearing a small distal prominence ( Figs 13, 14 ). Coxa of male 7th leg­pair with a mesal prominence, forming a sharp angle with main body of coxa. Prefemur of male 7th leg­pair strongly swollen mesally ( Fig. 15 ).

Remarks. This species resembles B. armatum , having a similar gonopod structure and the 7th male prefemur strongly swollen. In particular, it agrees with B. armatum in having a spatulate subanterior gonopodal coxal process, and in having the distal gonopodal process hook­shaped and sigmoid. The two species are also the only ones having modified 7th male leg coxae. B. bulgaricum differs from armatum , however, by having the subanterior gonopodal process long and slender (instead of short, mushroom­like), in having the main femoral process pointing downward and divided in its apical part (instead of pointing upward and not divided). So far, B. bulgaricum has been found in a single cave, which is situated in the southern slopes of the Pirin Mts. near to the junction with the Slavyanka (Orvilos) Mts. and also superficially in Slavyanka Mts. It seems restricted to the region of Slavyanka ­ Pirin only and could be expected in yet unexplored caves in the highland zone of the Slavyanka. It has been collected near to the border with the Republic of Greece and might be found there also. In the Starshelitsa Cave it coexists with other troglomorph invertebrates like Illyrionethes sp. (Isopoda) , Lithobius lakatnicensis Verhoeff, 1926 (Chilopoda) and Centromerus acutidentatus Deltshev, 2002 (Araneae) .

Figures

FIGURES 13­15. Balkanopetalum bulgaricum sp.n. Figs. 13­14. Male gonopods, mesal (Fig. 13) and lateral (Fig. 14) view. Cx ­ Coxa; ACxPr ­ Anterior coxal processes; SubACxPr ­ Subanterior coxal process; PCxPr ­ Posterior coxal process; Fe ­ Femoroid; FePr ­ Femoroidal process; DPr ­ Distal process; OP ­ Ovoid plate; ST ­ Solenomerite; SG ­ Seminal groove; DProm ­ Distal prominence of solenomerite. Fig. 15. Coxa, trochanter, prefemur and femur of male 7th leg­pair. Cx ­ Coxa; CxMP ­ Coxal mesal prominence; Tr ­ Trochanter; PFe ­ Prefemur; Fe ­ Femur.