Heterolatzelia karlstrasseri Antić and Makarov, 2015

Antić, Dragan Ž., Tomić, Vladimir T., Rađa, Tonći, Lučić, Luka R., Dudić, Boris D. & Makarov, Slobodan E., 2015, A new species of the family Heterolatzeliidae from the Balkan Peninsula (Diplopoda, Chordeumatida), Zootaxa 3904 (1), pp. 147-150 : 147-149

Heterolatzelia karlstrasseri Antić and Makarov , new species

Figs. 1–4

Material examined. Holotype: male from the Đatlo Cave (43°03'42.01"N, 18°29'40.87"E), Kobilja Glava, village of Korita, boundary of the municipalities of Bileća and Gacko, Bosnia and Herzegovina, collected on July 14, 2013 by T. Rađa (IZB, HTL HK 100-1). Paratypes: four juveniles, same data as holotype (IZB, HTL HK 100-2). The type material is deposited in the collection of the Institute of Zoology, Faculty of Biology, University of Belgrade, Serbia (IZB).

Etymology. In honor of the late Dr. Karl Strasser, one of the greatest European diplopodologists, whose contribution to our knowledge of the Balkan millipede fauna is invaluable.

Description. Body with 30 segments (including telson) in holotype male. Juveniles with 28 segments (including telson). Dorsal and ventrolateral side of metazonites brownish, prozonites, lateral keels, and anterior part of metazonites yellowish. Body length 12.64 mm (holotype male). Vertical diameter of the largest pleurotergites 0.92 mm (holotype male).

Head (holotype male): With five rows of 22 ocellae. Occipital axial suture short and clear. Labrum with three labral teeth, and with 5+6 labral and 2+2 supralabral setae. Ventral margins of stipes densely denticulated. Each stipe with one prominent anterior tooth with two setae. Gnathochilarium without any peculiarities. Promentum triangular; stipites with 4+4 long marginal setae, 1+1 long apical setae, and 7+7 basal microsetae; lingual plates with two rows of 5+7 setae (2+2 inner setae, and 3+5 outer setae). Antennal length 2.1 mm. In length: antennomeres I <VII <VI <II ~ IV <V ~ III. Length/breadth ratios of antennomeres I–VII: 1 (I), 2.27 (II), 8.14 (III), 3.57 (IV), 4.90 (V), 2.09 (VI), and 1.88 (VII), respectively. Antennomeres IV, V and VI with a few long sensitive setae.

Collum: Narrower than head, with six macrochaetae.

Pleurotergites: Lateral keels well developed, with two rounded lobes, becoming larger from pleurotergite V, poorly developed on pleurotergites XXVI and XXVII, disappearing on pleurotergites XXVIII and XXIX. Macrochaetae short, trichoid. Macrochaetal index CIX (pleurotergite 15), i.e., distance between exterior and median macrochaetae/distance between interior and median macrochaetae = 0.58. Median index MIX (pleurotergite 15) i.e., distance between interior macrochaetae and axial suture/distance between interior and median macrochaetae = 0.74. Paratergal index PIX (pleurotergite 15), i.e., (width of metazonite - width of prozonite)/(2 x length of paratergum) = 0.95. The macrochaetal angle between the arm created by the median and exterior macrochaetae and the arm formed by the median and interior macrochaetae, MA (pleurotergite 15) ~120˚.

Telson: Epiproct with expanded apical part (dorsal view), and with pair of spinnerets. Each paraproct with three short marginal setae. Hypoproct subquadrangular with two long apical setae.

Walking legs (holotype male): Coxae and prefemores with denticles. Tarsi with papillae, and with two additional tarsal claws (one long and thin subapical accessory claw and one rudimentary claw situated at the base of the main claw).

Male sexual characters: Head with concave frontal side. Leg-pairs 1 and 2 slightly reduced, with tarsal brushes ventrally. Leg-pairs 3–7 somewhat enlarged, with tarsal papillae, and with more or less swollen podomeres. Leg-pairs 10 and 11 with coxal glands, without any additional processes.

Anterior gonopods ( Figs. 1–3 ): With a single, wide subquadrangular part (e) on the oral side. Anterior part with three elements. Angiocoxites (a) are the most dominant and the longest elements; apically curved mesad; basal part wide in lateral view; with caudal bulges (cb). Large areas of angiocoxites are covered with papillae. Colpocoxites (c) shorter than angiocoxites, orally connected to each other by lamella (l). Basal halves wide, subquadrangular in caudal view, and clearly separated from each other. Caudo-mesal sides of apical parts of colpocoxites with lobuses covered by papillae. From the widest parts of colpocoxites to their apical parts there are thin sutures. The third element is a comb-like process (b), starting from the oral side of anterior gonopods and slightly curving to the posterior part. These elements are sigmoid from the oral side, and 2/3 of their total length is covered with thin sutures. Apical parts are in the form of combs with 8+9 teeth (f) on the caudal side. Lateral sides of apical parts are devoid of teeth. Posterior part of anterior gonopods consists of large spoon-shaped coxal cavity (d).

Posterior gonopods ( Fig. 4 ): Massive, ovoid, consist of unique ladle-shaped coxites. Apical parts covered with short setae; orally with 2+2 setae (1+1 shorter and 1+1 longer). Posterior gonopods with telopodital remnants (t), each with nine long setae.

MAP. Distribution of the family Heterolatzeliidae Verhoeff, 1897 .

Taxonomic note. Within the genus Heterolatzelia , two species are closely related to each other: H. durmitorensis and H. karlstrasseri sp. n. These species clearly differ from H. nivalis by the presence of long angiocoxites and short colpocoxites (these elements are almost the same length in H. nivalis ). Apart from similarities in habitus and gonopodial structures, H. durmitorensis and H. karlstrasseri sp. n. are also geographically close (Map).

In our description of the new species, we referred to the drawing of H. durmitorensis given in the paper of Mršić (1992), where he indicated that he examined numerous individuals of this species. Heterolatzelia karlstrasseri sp. n. and H. durmitorensis differ clearly from each other in some structures of the gonopods, such as the presence of a wide subquadrangular part on the oral side of the anterior gonopods in the new species vs. absence of this part in H. durmitorensis ; apically curved mesad angiocoxites vs. almost straight aniocoxites; colpocoxites with wide, subquadrangular basal halves vs. almost triangular colpocoxites; colpocoxites connected to each other by lamella on the oral side vs. absence of such connecting lamella; absence of small medial fimbriate processes on the inner edges of colpocoxites vs. presence of these processes; and ovoid vs. subquadrangular posterior gonopods.

Figures

FIGURES 1 – 4. Heterolatzelia karlstrasseri sp. n., holotype male gonopods. 1. anterior gonopods, oral view; 2. anterior gonopods, caudal view; 3. anterior gonopods, lateral view; 4. posterior gonopods, oral view. Designations: a: angiocoxite; b: comb-like process; c: colpocoxite; d: coxal cavity; e: wide subquadrangular part; f: teeth of comb-like process; l: connecting lamella between colpocoxites; t: rudimentary telopodites; cb: caudal bulges of angiocoxite. Scale line: 0.4 mm.