Balkanodesmus biokovensis Antić and Reip, 2014

Antić, Dragan Ž., Reip, Hans S., Dražina, Tvrtko, Rađa, Tonći & Makarov, Slobodan E., 2014, Three new monotypic genera of Trichopolydesmidae from Croatia, Balkan Peninsula (Diplopoda, Polydesmida), Zootaxa 3884 (2), pp. 101-121 : 102-106

Balkanodesmus biokovensis Antić and Reip , sp. n.

Figs. 1 –12

Material examined: Holotype male: Amfora Pit, Saint Jure, Mt. Biokovo, Croatia, 43.341°N, 17.050°E, 14.VII.2008, leg. J. Bedek (IZB, VHD BB 100-2). Allotype female: same data as holotype, but 17.VII.2008, leg. M. Lukić (IZB, VHD BB 100-3). Paratype juvenile female: same data as holotype (IZB, VHD BB 100-4).

Etymology: After Mt. Biokovo, the type locality.

Description. Body with 19 segments (including telson) in adults (paratype juvenile female with 18 segments). Measurements: holotype male 17.8 mm long, width of midbody pro- and metazonites (segment nine) 1.0 mm and 1.4 mm; allotype female 17.9 mm long, width of midbody pro- and metazonites (segment nine) 1.0 mm and 1.4 mm; paratype juvenile female 12.9 mm long, width of midbody pro- and metazonites (segment nine) 0.8 mm and 1.1 mm, respectively.

Coloration: Body whitish, slightly translucent, with a visible gut; head light brownish with whitish antennae.

Head: Broader than collum, covered with fine short and some longer setae. Occipital suture distinct. Labrum with only one long, medial, laterally flattened and ventrally curved tooth; two paramedian, short, blunt setae, one on each side of the tooth. Tooth significantly darker than labrum (Fig. 12). Gnathochilarium (in allotype female) densely setose. Setae robust. Promentum almost triangular, with four setae in one medial row. Stipites with more than 30 setae each. Lingual plates with about 20 setae each, with a long, paramedian, subapical seta on each plate and with one long, paramedian, apical, setiform, distally branching process on each plate. External palps with 18+18, medial palps with 15+15, internal palps with 4+4 papillae. Internal palps bearing one long seta crossing medially. Hypopharynx with strongly developed, long and thin fringes ( Fig. 11 ). Antennae elongated; in holotype male 2.5 mm long. Antennomeres II–VI club-like, elongated; antennomere VII cylindrical and shorter. Antennomeres V and VI with few longer setae; antennomere VI with a distodorsal pit with numerous bacilliform sensilla. Antennomere VII with one longer seta and a distodorsal pad with few setiform setae. Apical part of antennae with four large apical cones. Length/width ratios of antennomeres I–VII: I (0.7), II (3.1), III (3.5), IV (2.5), V (2.1), VI (1.7), VII (1.7), respectively.

Collum: Transversely subovoid; one caudal incision on lateral sides, with three rows of setae on small tubercles, setal formula: 8+8+8.

Body segments: Segments II–IV with three rows of medium-sized trichoid setae on small tubercles while segments V–XVIII with mainly four, partly five, irregular transverse rows of setae. Pleurosternal carinae with welldeveloped triangular teeth present on each side of segments II–XVII. Apodous (XVIII) segment without pleurosternal carinae. Number of teeth variable not only between specimens and segments of same specimen, but also between right and left sides of same segment. Number of teeth in holotype male: segments II and III (6/6); IV (5/5); V and VI (7–9); VII (5/7); VIII–XI (8–10); XII–XIV (10–12); XV–XVII (8–9), respectively. Prozonite slightly punctate. Stricture distinct. Paraterga with three dorsolaterally positioned, laterally directed cones; each bearing one seta. Last cone on each poriferous metazonite enlarged and bearing an ozopore and 3–4 setae. These enlarged cones also contain reactivation chambers of the defense mechanism. Pore formula normal: V, VII, IX, X, XII, XIII, XV–XVIII. Epiproct short, but protruding beyond paraprocts, slightly curved caudoventrally; subtriangular in dorsal view, truncate at tip, dorsally with long setae. Tip of epiproct with 2+2 spinnerets. Paraprocts semi-circular, smooth, each with two setae. Hypoproct subtrapeziform, with four long apical setae. Sterna unmodified. Epigynal ridge elevated.

Walking legs: Long and slender, without modified setae. Femora and tarsi elongated, claws medium-sized and clearly infuscate.

Gonopods: Gonopod aperture large, transverse-oval, taking up circa 2/3 of ventral part of metazonite VII. Gonocoxa large, exposed, subglobose, with two distofrontal setae and one distocaudal seta, with neither additional processes nor protruding parts. Prefemoral part (pf) slender, held transversely to body axis, curved caudally, with almost straight margins. First 1/3 smooth, second 1/3 only with apical setae, remaining 1/3 densely setose. Acropodite (a) erect, long, unipartite and parallel-sided; directed frontally. Basal part with setae and a narrow, longitudinal, mesal lamella (ll) reaching the first, most shallow and widest (basal) lamella (bl) in middle part of acropodite. A second, deeper and narrower (middle) lamella (ml) above bl and the narrowest and deepest (apical) lamella (al) above ml. Seminal canal probably opening at base of al. Solenomere absent. Apart from ml, middle part of acropodite bearing characteristic, short, triangular denticles (d) associated with ml and al. Apical part of acropodite long and slender, with two apical lobes (lo) and a mesally directed, triangular, acute tip (tp).

Habitat: Amfora Pit, where Balkanodesmus biokovensis was collected, is a 788-meter deep. The entrance of the pit is situated at an altitude of 1,620 m. All three specimens were collected between a depth of 100 to 400 meters. The almost stable air temperature ranged from 5.1 to 5.4°C ( Lukić et al. 2010). This pit hosts another endemic troglobitic diplopod, Biokoviella mauriesi Mršić, 1992 . Amfora Pit is also the type locality for the interesting, highly troglomorphic collembolan, Tritomurus veles Lukić, Houssin & Deharveng, 2010 ( Lukić et al. 2010) . Furthermore, other notable troglobitic taxa are present in the pit ( Lukić et al. 2010), such as: Zospeum sp.

(Gastropoda), Protoneobisium biocovense (Müller, 1931) , Neobisium peruni Ćurčić, 1988 (both Pseudoscorpiones ), Speoplanes giganteus biocovensis Müller, 1934 , Radziella styx Casale & Jalžić,1989 (both Coleoptera , Leiodidae ) and Biokovoaphaenopsis radici Jalžić, 1993 ( Coleoptera , Carabidae ).

Figures

FIGURES 1 – 6. Balkanodesmus biokovensis gen. n., sp. n., holoype male (1 – 5). 1: habitus, lateral view, 2: body segments VIII – X, dorsal view, 3: body segments VI – VIII, lateral view, 4: gonopods, lateral view, 5: gonopods, in situ. Paratype juvenile female. 6: body end, lateral view. Scale line: 1 mm (1 – 3), 0.2 mm (4 – 5) and 0.5 mm (6).

FIGURES 11 and 12. Balkanodesmus biokovensis gen. n., sp. n., allotype female. 11: dorsal view of gnathochilarium and hypopharinx, 12: labrum. Scale line: 0.3 mm