Spelaeobates (Spelaeobates) coriniensis Curcic , Vesovic , Vrbica & Rađa, 2023

Curcic, Srecko, Vesovic, Nikola, Vrbica, Maja, Popovic, Slađana, Radovanovic, Zeljko, Curcic, Nina B., Yamashkin, Anatoliy A., Radovic, Dejan, Yamashkin, Stanislav A., Vranic, Sofija & Rađa, Tonci, 2023, The surprising discovery of two new subterranean Leptodirini of the genus Spelaeobates Mueller, 1901 (Coleoptera, Leiodidae, Cholevinae) from Croatia after more than a century, Subterranean Biology 46, pp. 21-46 : 21

publication ID	https://dx.doi.org/10.3897/subtbiol.46.104548
publication LSID	lsid:zoobank.org:pub:17340FB7-14C8-4903-B1E4-8B209FE73C93
persistent identifier	https://treatment.plazi.org/id/2F317FC3-634B-4EDB-886C-5BC4C008639A
taxon LSID	lsid:zoobank.org:act:2F317FC3-634B-4EDB-886C-5BC4C008639A
treatment provided by	Subterranean Biology by Pensoft
scientific name	Spelaeobates (Spelaeobates) coriniensis Curcic , Vesovic , Vrbica & Rađa
status	sp. nov.

Treatment

Spelaeobates (Spelaeobates) coriniensis Curcic, Vesovic, Vrbica & Rađa sp. nov.

Figs 2 View Figure 2 , 3 View Figure 3 , 6 View Figure 6

Type material.

Holotype: male (SSM) labeled as follows: "CROATIA, NORTHERN DALMATIA: town of Benkovac, settlement of Gornji Karin, village of Popovići, Jamurka ( Rnjakuša II) Pit, 216 m a.s.l., 44°04'44.1"N, 15°41'00.3"E, 8.II.2019, TR" (white label, printed) / "Holotypus Spelaeobates (Spelaeobates) coriniensis sp. nov. Ćurčić, Vesović, Vrbica & Rađa det. 2022" (red label, printed).

Paratypes (three males and five females). The same data as for HT (IZFB). All paratypes are labeled with white, printed locality labels and with red printed labels "Paratypus Spelaeobates (Spelaeobates) coriniensis sp. nov. Ćurčić, Vesović, Vrbica & Rađa det. 2022" (Fig. 2 View Figure 2 ).

Etymology.

Spelaeobates (Spelaeobates) coriniensis sp. nov. is named after Corinium, a Roman town in the area of today’s Gornji Karin, a settlement close to its type locality.

Diagnosis.

The new species is most closely related to another species of Spelaeobates s. str., S. novaki , by the rimmed lateral pronotal margins, the presence of a dilated first protarsomere in males, a low, unangled mesoventral carina, the presence of its apically attenuated median lobe of the aedeagus, and by the presence of four parameral setae (Figs 2 View Figure 2 , 3 View Figure 3 , 7 View Figure 7 , 8 View Figure 8 ) ( Müller 1901; Jeannel 1924; Guéorguiev 1976).

Spelaeobates (S.) coriniensis sp. nov. is easily distinguished from S. (S.) novaki in terms of TL (R 2.37-2.50 mm vs. R 2.50-2.80 mm), length of antennae when stretched backwards (reaching end of elytra vs. not reaching end of elytra), length of first two antennomeres (antennomere II longer than antennomere I vs. antennomeres I and II approximately equal in length), A6L/A3L (M 0.93, R 0.88-1.00 vs. M 0.79, R 0.76-0.82), A8L/A3L (M 0.85, R 0.75-0.93 vs. M 0.65, R 0.59-0.71), A11L/A8L (M 1.94, R 1.77-2.08 vs. M 2.27, R 2.09-2.40), maximum width of head (between first quarter and third vs. between first third and middle), punctuation on pronotum (fine, punctures separated vs. strong, punctures merged), EL/EW in males (R 1.56-1.71 vs. R 1.53), maximum width of elytra (before middle vs. around at middle), EW/PW (R 2.15-2.34 vs. R 2.37-2.50), width of first protarsomere in males (less broadened vs. more broadened), and shape of median lobe of aedeagus in dorsal view (more narrowed distally, pointed apically vs. gradually narrowed distally, almost sub-parallel, rounded apically) and in lateral view (less curved basally, almost straight apically vs. more curved basally, slightly bent downward apically) (Table 1 View Table 1 , Figs 2 View Figure 2 , 3 View Figure 3 , 7 View Figure 7 , 8 View Figure 8 ) ( Müller 1901; Jeannel 1924; Guéorguiev 1976).

Description.

Small-sized leptodirine. TL M 2.42 mm (2.43 mm in males, 2.41 mm in females), R 2.37-2.50 mm (2.37-2.50 mm in both males and females).

Habitus: Body shape leptodiroid (Fig. 2A, B View Figure 2 ), colour yellowish.

Integument: Lustrous, microsculptured both dorsally and ventrally (Fig. 2C, D, F-L View Figure 2 ). Sparsely distributed deep punctures present on head, while densely distributed, fine and separated on both pronotum and elytra (Fig. 2C, D, F, G, K, L View Figure 2 ). Entire body dorsally covered with yellow pubescence of short length (erect on head, while recumbent on both pronotum and elytra) (Fig. 2A, B View Figure 2 ).

Head: About one and a half times as long as wide (HL/HW M 1.49, R 1.37-1.65), more elongate in males (HL/HW M 1.52 in males, M 1.46 in females), with no eyes, occipital carina in the shape of a curved concave line (Fig. 2A, C View Figure 2 ). Head widest between first quarter and third. Frons roundly impressed between antennal insertions. Labrum transverse, with a few long setae. First maxillary palpomere of similar length and width, shorter than second maxillary palpomere. Maxillary palpomeres II and III of similar length (M3L/M2L M 1.02, R 0.85-1.09). Penultimate maxillary palpomere widened apically. Ultimate maxillary palpomere short, slender, gradually narrowing apically. Antennae inserted in basal quarter of head, thin, narrow proximally (except for first two antennomeres, which are thickened), slightly widened distally, longer in males, AL M 1.83 mm, R 1.71-1.97 mm (1.88-1.97 mm in males, 1.71-1.82 mm in females), reaching end of elytra in males (Fig. 2A, B, E View Figure 2 ). Antennomeres I and II short and wide, second of which slightly longer and narrower. Following four antennomeres thinner and slightly longer than antennomere II. Antennomere III longer than adjacent antennomeres (A3L/A2L M 1.26, R 1.15-1.33; A3L/A4L M 1.09, R 1.00-1.15). Antennomeres VII, IX, and X quite expanded distally. Antennomere VIII relatively short and narrow, shorter and narrower than anatennomeres VII, IX, X, and XI. Ultimate antennomere slender, widened sub-distally, then narrowing apically, narrower than penultimate one (A11W/A10W M 0.78, R 0.67-0.83). Antennomere I shortest, while antennomeres IX and XI longest. Other ratios of length of certain antennomeres: A6L/A3L M 0.93, R 0.88-1.00; A8L/A3L M 0.85, R 0.75-0.93; A11L/A8L M 1.94, R 1.77-2.08.

Prothorax: Pronotum bell-shaped, elongate, longer than wide (PL/PW M 1.24, R 1.21-1.28; M 1.26, R 1.24-1.28 in males; M 1.23, R 1.21-1.27 in females), widest around anterior third, broader (HW/PW M 0.89, R 0.87-0.92) and shorter than head (PL/HL M 0.95, R 0.89-0.98) (Fig. 2A, F View Figure 2 ). Lateral margins rounded anteriorly, after which they constrict towards posterior end, slightly concave posteriorly. Pronotal base straight, somewhat shorter than elytral base. PB/AM M 0.86, R 0.81-0.93. Anterior margin barely convex medially, almost straight. Lateral margins and pronotal base rimmed. Fore pronotal angles weakly expressed, rounded, obtuse. Hind pronotal angles well-expressed, obtuse, not protruding backwards. Pronotal disc moderately convex (Fig. 2B View Figure 2 ).

Mesothorax: Mesoventral carina very low, barely noticeable, with a few setae (Fig. 2H View Figure 2 ). No tooth, anterior and posterior margins observed. Mesoventrite with a long process between mesocoxae, which is gradually narrowing apically (Fig. 2I View Figure 2 ). Scutellum large, sub-triangular (Fig. 2K, J View Figure 2 ).

Metathorax: Metaventrite without carina.

Elytra: Wide, ovoid, almost of same width in males and females (EL/EW M 1.64, R 1.56-1.71 in males; M 1.64, R 1.60-1.69 in females), markedly wider than pronotum (EW/PW M 2.25, R 2.15-2.34) (Fig. 2A, K View Figure 2 ). Maximum width a little before middle. Lateral margins arcuate. Marginal furrows not visible from above. Shoulders barely visible, obtuse, covered by hind pronotal angles. Elytral disc markedly convex, steeply declining both basally and apically in lateral view (Fig. 2B View Figure 2 ). Parasutural stria absent. Elytral apex slightly attenuated, rounded. Pygidium covered by elytra.

Legs: Elongate and slender (Fig. 2A, B View Figure 2 ). Femora widened basally, constricted in distal half. Tibiae thin, gently curved, gradually widening distally. Each protibia with a very fine comb over entire apical third of outer margin. Fore tarsi four-segmented in both sexes, only first protarsomere in males dilated (P1W/P2W M 1.75, R 1.50-2.00). Tarsal claws thin, elongate, curved, pointed apically.

Male genitalia: Aedeagus elongate, slender, small, well chitinised (Fig. 3A, B View Figure 3 ). Median lobe in dorsal view straight, gradually narrowing distally, with a sharp apex, markedly longer than parameres (Fig. 3A View Figure 3 ). Median lobe in lateral view quite flattened, curved basally, almost straight proximally, narrowing apically (Fig. 3B View Figure 3 ). Basal bulb small, narrow, sub-parallel, slightly widened distally and bilobed in dorsal view (Fig. 3A View Figure 3 ), while elongate and widened basally in lateral view (Fig. 3B View Figure 3 ). Tegmen wide from above (Fig. 3A View Figure 3 ), in the shape of a ring around basal bulb (Fig. 3B View Figure 3 ). Parameres elongate, slender, arcuate, sub-apically curved exteriorly, each with a moderately widened rounded apex in dorsal view (Fig. 3A View Figure 3 ), while straight, sub-parallel in lateral view (Fig. 3B View Figure 3 ). Each paramera bearing four apical close-set setae, two of which longer, while two shorter (Fig. 3A View Figure 3 ). No copulatory piece observed within inner sac (Fig. 3A, B View Figure 3 ).

Female genitalia: Spermatheca small, chitinised, curved, markedly constricted medially, spherical both basally and apically (Fig. 6A View Figure 6 ). Gonostyli short, straight, moderately widened, gradually narrowing distally, pointed apically (Fig. 6B View Figure 6 ). Each gonostylus carrying one long apical seta.

Male abdominal sternite IX (urite): Small, narrowing apically, sub-triangular.

Female abdominal ventrite VIII: Small, transverse, with no anterior process, hairy, especially posteriorly.

Sexual dimorphism.

Some degree of sexual dimorphism was noted in this new species. Namely, it was found that: (i) antennae are longer in the males than in the females; (ii) antennomeres VIII-X are more elongate in the males than in the females; (iii) head is more elongate in the males than in the females; (iv) pronotum is slightly more elongate in the males than in the females; (v) first protarsomere is wider in the males than in the females.

Type locality.

Jamurka ( Rnjakuša II) Pit, village of Popovići, close to the settlement of Gornji Karin and the town of Benkovac, northern Dalmatia, Croatia.

Geographic distribution.

The new species inhabits a few pits in the vicinity of the town of Benkovac and the city of Šibenik in northern Dalmatia (Croatia). Its type locality, the Jamurka ( Rnjakuša II) Pit, represents the northernmost location of a Spelaeobates species. At the same time, this is the first official finding of a species of the genus Spelaeobates on the mainland, which confirms that this genus is distributed both on the islands and on the mainland of Dalmatia ( Jalžić 1982). It is possible that the new species also inhabits the surrounding subterranean habitats in northern Dalmatia.

Bionomy and habitat.

Individuals of S. (S.) coriniensis sp. nov. were collected by hand from the walls and floor in the innermost part of the Jamurka ( Rnjakuša II) Pit, in places that were in complete darkness, with a high degree of humidity and the presence of trickling water.