Brachychaetosoma turbanovi

Antić, Dragan Ž. & Makarov, Slobodan E., 2016, The Caucasus as a major hotspot of biodiversity: Evidence from the millipede family Anthroleucosomatidae (Diplopoda, Chordeumatida), Zootaxa 4211 (1), pp. 1-205 : 23-28

Brachychaetosoma turbanovi gen. et sp. nov.

Figs 15–17

Diagnosis. As for the genus.

Etymology. The new species is named after Ilya Turbanov, a member of the “Zelenye Kamneyedy” Speleological Club, Sevastopol, Crimea, the collector.

Material studied (total: 1 male, 1 female). Holotype. ABKHAZIA: male, Ochamchire District, near Otap , Cave Marshania , 12 Sep. 2014, I. S. Turbanov leg. ( ZMUM ρ3227).

Paratype (total: 1 female). ABKHAZIA: 1 female, same data as holotype ( ZMUM ρ3228).

Type locality. ABKHAZIA: Ochamchire District, near Otap , Cave Marshania.

Description. Body with 30 segments (including telson) in adults.

MEASUREMENTS. Holotype male 15.5 mm long, vertical diameter of the largest pleurotergite 1.3 mm. Paratype female 14.5 mm long, vertical diameter of the largest pleurotergite 1.3 mm.

COLORATION ( Fig. 15 ). Uniformly greyish to yellowish white.

HEAD. Frons slightly concave in male. Labrum with three medial teeth and 4+4 labral and 2+2 supralabral setae. Promentum triangular, without setae. Lingual plates with 7+7 setae, on each plate arranged in two irregular rows. Stipites with ca 27+27 setae. Antennae 2.4 mm long in holotype. Length of antennomeres (in mm): I (0.1), II (0.27), III (0.63), IV (0.32), V (0.63), VI (0.23), VII (0.2) and VIII (0.02). Length/breadth ratios of antennomeres I– VII: I (1), II (1.7), III (5.2), IV (2.3), V (4.2), VI (1.5) and VII (2). Antennomeres II, IV, V, VI and VII with one, three, one, four and one sensillum, respectively. Number of ocelli 6, arranged in 2–3 irregular rows in holotype; 5– 6 in 3 rows in paratype female.

COLLUM. Narrower than head, with six macrochaetae. Anterior edge semi-circular, posterior margin gently concave.

BODY SEGMENTS ( Fig. 15 ). Lateral keels like lateral swellings. Macrochaetae very short and blunt. CIX (pleurotergite 15) ~ 0.7; MIX (pleurotergite 15) ~ 0.5; PIX (pleurotergite 15) ~ 0.5; MA (pleurotergite 15) ~ 150˚.

TELSON. Epiproct with a pair of spinnerets and 3+3 setae (1+1 paramedian, 2+2 marginal). Hypoproct with 1+1 apical setae. Paraprocts with 3+3 marginal setae.

WALKING LEGS. In both sexes, leg-pairs 1 and 2 with tarsal combs; prefemora with several long and robust setae; femora and postfemora with a group of several long and robust setae.

MALE SEXUAL CHARACTERS ( Fig. 16 ). Leg-pairs 3–7 enlarged, leg-pairs 3, 4 and 7 especially so. Leg-pairs 3 and 4 each with a basal exterior protrusion on prefemur; all podomeres enlarged, femora especially so. Leg-pair 5 with a basal oral protrusion on prefemur. Leg-pair 6 without peculiarities. Leg-pair 7 with an unusual posterior coxal process, this being wide and rounded, at base with nipples on posterior side, then acuminate; prefemora with two well-developed horns, one apical, the other basal, placed opposite to each other, basal one curved dorsad, apical one curved ventrad and showing nipples. Leg-pair 10 with coxal glands and with two coxal processes, mesal process with nipples, lateral one acuminate, subtriangular. Leg-pair 11 with coxal glands, without other peculiarities.

ANTERIOR GONOPODS ( Fig. 17 A–C). Sternal plate (sp) with a well-developed, medial, hairy sternal sac (ss) with a hairless and concave cental part. Coxal processes (ap) wide, shield-like, distal half with U-shaped rift, basal half fused. A medial, unpaired, distally bifurcated process (bp) placed anteriorly and fused basally to shields is the most characteristic structure of the anterior gonopods Both shields and medial bifurcated process orientated posteriorly. Posterior side characterized by longitudinal lamellae (l1) starting from apices of shields (a). Apicall third of lamellae narrowing, with small nipples and denticulate edges, remaining parts of lamellae wider with denticulate edges. One more, shorter lamella (l2) starting with a densely denticulate upper part and placed under apical, nippled part of longitudinal lamellae. Mesal egdes of shields folded inside and forming a pair of lamellar posterior projections (ppr) on posterior side, clothed with small setules. A row of long setae (rs) can be observed on posterior side between these lamellar projections and the wider part of longitudinal lamella.

POSTERIOR GONOPODS ( Fig. 17 D). Coxites (c) divided. Telopodites (t) two-segmented, with few short setae present on posterolateral side. Coxal processes (cp) simple, rounded apically, curved posteriorly. Coxal vesicles (cv) present on anteromesal side.

Notes. This species is known only from a cave and shows some troglomorphic features such as reduced pigmentation and number of ocelli.

Figures

FIGURE 15. Brachychaetosoma turbanovi gen. et sp. nov., paratype female. A. Habitus. B. Pleurotergites with short macrochaetae. Scale lines = 1 mm.

FIGURE 16. Brachychaetosoma turbanovi gen. et sp. nov., holotype male. A. Leg 3. B. Leg 4. C. Leg 7. D. Leg 10. Scale lines = 0.4 mm.

FIGURE 17. Brachychaetosoma turbanovi gen. et sp. nov., holotype male gonopods. A. Anterior gonopods, anterior view. B. Anterior gonopods, lateral view. C. Anterior gonopods, posterior view. D. Posterior gonopods, posterior view. a = apex of the shield; c = coxite; t = telopodite; bp = bifurcated process; cp = coxal process; cv = coxal vesicle; l 1 = longitudinal lamella; l 2 = shorter lamella; rs = row of setae; sp = sternal plate; ss = sternal sac; ppr = posterior projection. Scale line = 0.3 mm.