Telestes dabar, Telestes miloradi, Telestes metohiensis, Telestes croaticus, and Telestes fontinalis are distinguished from all congeners by having the pharyngeal teeth in one row, 5–4 or 5–5 (vs. usually 2.5–5.2 or 2.5–4.2), having the preoperculo-mandibular canal terminating in a free pore at the upper margin of the opercular antedorsal process and not communicating with the infraorbital canal (vs. communicating), and in lacking a postcleithrum (vs. postcleithrum present). All five species possess a dark midlateral stripe from the head to the caudal peduncle that forms the ventral border of the darkly pigmented area on the back. This feature is similar to that in some other Telestes species (Kottelat and Freyhof 2007: 282–289). Within this group, Telestes dabar, Telestes miloradi, and Telestes metohiensis differ from Telestes croaticus and Telestes fontinalis in having an additional black lateral stripe occurring on the otherwise pale ventral portion of the trunk. This character was considered unique for Telestes metohiensis (Kottelat and Freyhof 2007: 284). In Telestes dabar and Telestes miloradi this ventral stripe (Fig. 1a, 2a, 7) is narrow and extends from just behind the operculum maximally to a vertical through the origin of the anal fin. In Telestes metohiensis, the stripe (Fig. 1b, 2b–c) is wide and usually extends posteriorly to the caudal peduncle where it merges with the main pigmented area. The pale area between the dark area on the back and the ventral stripe varies in length and depth, being the smallest in females (Fig. 1b, 2b–c).

Besides the presence of the ventral stripe, Telestes dabar and Telestes miloradi are further distinguishable from Telestes croaticus and Telestes fontinalis by usually having 8½ branched dorsal-fin rays (vs. usually 7½). Telestes dabar differs from Telestes croaticus by usually having 40 total vertebrae (vs. usually 39) (Table 4); a maximum head width of 42–52% HL (averaging 50% HL in females and 48% HL in males), which is considerably smaller than the head depth at nape, 61–71% HL (averaging 67% HL in females and 65% HL in males) (vs. the maximum head width only slightly smaller than the head depth or about equal to it); and a smaller size, up to 82 mm SL (vs. up to 160 mm). Telestes dabar can befurther distinguished from Telestes fontinalis by having 5–4 pharyngeal teeth (vs. 5–5); a usually long, though slightly incomplete and narrowly interrupted, lateral line that reaches the posterior half of the caudal peduncle and has 24–69, usually 54–65, total scales (vs. a short, incomplete, and widely interrupted lateral line terminating in the area between the pectoral and anal fins with usually 23–37 total scales); usually 17 or 18 caudal vertebrae (vs. 16); usually 13 or 14 predorsal vertebrae (vs. 15) (Table 4); 3 or 4 intermediate vertebrae (vs. 5); and a moderately compressed body without any ventral keel (vs. a markedly laterally compressed body and a scaled ventral keel in front of the pelvic fins).

Telestes miloradi further differs from Telestes croaticus and Telestes fontinalis in usually having a long, complete lateral line with 55–67 scales vs. an often incomplete and interrupted lateral line with (18–45)51–70 and (17)23–37(56) scales, respectively. The new species further differs from Telestes croaticus in having 8–10, most frequently 9, gill rakers, (vs. 8–9, most frequently 8); usually 40 or 41 total vertebrae (vs. 38 or 39); 22–23, mode 23, abdominal vertebrae (vs. 21–23, mode 22); and 17–19, mode 18, caudal vertebrae (vs. 16–17, mode 17) (Table 4). Telestes miloradi can befurther distinguished from Telestes fontinalis by having 5–4 pharyngeal teeth (vs. 5–5); usually 40 or 41 total vertebrae (vs. 38–40, usually 39); 17–19, usually 18, caudal vertebrae (vs. 16–17, often 16) (Table 4); 3 or 4 intermediate vertebrae (vs. 5); and a moderately compressed body without a ventral keel (vs. a markedly laterally compressed body and a scaled ventral keel in front of the pelvic fins).

Telestes miloradi differs from Telestes croaticus, Telestes fontinalis, Telestes metohiensis, and Telestes dabar in having comparatively well-overlapped scales, especially on the anterior part of the flank and on the caudal peduncle; and scales of about the same size in the lateral line and above and below it (vs. scales usually non-overlapping on most of the body, and scales above and below the lateral line smaller than the lateral-line scales). The scale pattern in Telestes miloradi is very similar to the pattern found in most leuciscine fishes, e.g. Telestes karsticus Marčić & Mrakovčić, 2011 (Fig. 8), Telestes turskyi (Heckel, 1843), Telestes ukliva (Heckel, 1843). The presence of overlapping scales is a plesiomorphic feature for the Leuciscinae (Bogutskaya 1990, 1991), as is an interconnection of CPM and CIO (e.g., Telestes karsticus). In addition to overlapping scales, a few specimens of Telestes miloradi exhibit interconnected CPM and CIO.

In this study, we compared specimens of Telestes metohiensis from Gatačko, Cerničko, and Nevesinjsko poljes and found that specimens from the Nevesinjsko Polje (labeled as affinis by Steindachner although the name affinis was never published), though somewhat different in usually having smaller and more scattered scales, are similar to Telestes metohiensis from the Gatačko and Cerničko poljes in all other aspects examined by us (Tables 1c–d, 2–4). We suppose that a reason for Steindachner’s opinion could be the differences evident between the NMW specimens of Telestes metohiensis from the Gatačko Polje (Mušnica River, Gacko) and those from the Nevesinjsko Polje (Zalomka River) (Fig. 6). Additional material examined by us revealed that the differences noted above in scales may be size-dependent: larger specimens of Telestes metohiensis in both poljes usually have more densely set scales. A specimen of Telestes metohiensis from Gatačko Polje, NMW 51176:3 (87.9 mm SL) is designated here as lectotype to ensure taxonomic stability in the event that Telestes metohiensis from the Nevesinjsko Polje is recognised as taxonomically distinct in the future.

Both Telestes dabar and Telestes miloradi are distinguishable from Telestes metohiensis by usually having 8½ branched dorsal-fin rays (vs. usually 7½: 7½ found in 192 specimens and 8½ in 22); 39–41, modes 40 and 41, total vertebrae (vs. 38–40, rarely 41, mode 39); 16–19, modes 17 and 18, caudal vertebrae (vs. 15–17, usually 16 or 17) (vs. 15–17, usually 16 or 17) (Table 4; differences are statistically significant at P<0.0001); and more numerous gill rakers, 9 or 10 (vs. (7)8–9(10), most frequently 8) (Table 2). Telestes dabar further differs from Telestes metohiensis in usually having an interrupted lateral line with 24–69, usually 54–65, total scales (vs. usually complete with 58–65 scales) (Table 3; difference is statistically significant at P<0.0001). The scale pattern also distinguishes Telestes dabar from Telestes metohiensis. In Telestes dabar, the scales (Fig. 3a) are densely set, but they do not overlap on most parts of the body except behind the pectoral girdle and on the caudal peduncle; the scales above and below the lateral line are only slightly smaller than the lateral-line scales; and the scales are oval, somewhat deeper than long, on the flanks and elongated, longer than deep with a prominent posterior attenuation, on the caudal peduncle. In Telestes metohiensis the scales are more or less widely spaced and do not overlap on the entire body except for the lateral line; this feature can be seen in live specimens, Fig. 2b); the scales (Fig. 3b) above and below the lateral line usually are considerably smaller than the lateral-line scales; and the scales are almost circular on both the flanks and the caudal peduncle. Telestes dabar is further distinguished from Telestes metohiensis by having a black-and-white general colouration except for yellowish-orange pigmentation of the fin bases and yellow pigmentation in the iris and along the operculum in adults (vs. yellowish-green or greenish-bronze pigmentation of the whole body and fins in both young and adults, Fig. 2b–c). With regard to the morphometric features, Telestes dabar is rather similar to Telestes metohiensis,differing only in having a narrower head, maximum head width 12–15% SL or 43–52% HL and maximum cranial width 60–73% cranium roof length (vs. 13–17% SL or 51–59% HL, and 64–80% cranium roof length) (Table 1; differences are statistically significant at P<0.0001).

Besides the characters mentioned above, Telestes dabar differs from Telestes miloradi in having the lateral-line scales larger than the scales above and below it (vs. of about equal size); usually an interrupted lateral line making a sharp curvature upward above the anal-fin base (vs. complete and making no sharp curvature); the length of lower jaw 10–12% SL, 36–41% HL, 102–132% depth of operculum (vs. 8–10% SL, 33–38% HL, 96–107% depth of operculum) (Table 1; differences are statistically significant at P<0.0001).

The three Telestes species are known from four of the 13 main karst poljes located in Eastern Herzegovina (Bosnia and Herzegovina) and in Dubrovnik littoral area (Croatia) (Fig. 4). These karst poljes are part of a high-karst geotectonic unit known as Dinaric Karst, which consists of Mesozoic carbonate formations. The depth of soluble and highly karstified rocks here exceeds 3000 m (Milanović 1981, 2006). A polje (means “field” in many Slavic languages) is a large closed depression draining underground with a flat floor. Its streams may be permanent, intermittent and perennial, and, in natural conditions, a polje is subject to periodic flooding and becomes a lake. In Eastern Herzegovina and in the Dubrovnik littoral area stepwise poljes are distributed from 60 m up to 1,080 m above sea level (Fig. 4). Streams and rivers appear from temporary or permanent springs and sink underground through swallow holes called ponors. In general, hydro-systems of all poljes under consideration (Fig. 4), except for the Konavosko Polje with direct connection to the Adriatic Sea and the Polje Gradac with no springs or surface flows, belong to the Neretva drainage area and form a complex net of underground flows. Within the Neretva drainage, the poljes belong to catchments of the Buna River (Slato and Nevesinjsko), the Bregava River (Lukavačko and Dabarsko), and the Trebišnijca River (Gatačko, Fatničko and others). At present, no one polje has a direct groundwater (surface) flow connection with Neretva or its tributaries. Historically, interconnections between variable surface streams and between them and the main Neretva course occurred during different geological epochs. Fish distributions can provide some evidence of this. Conversely, very local distribution of some fishes may indicate the isolation of some surface drainage systems for a long time.

Slato [Zlato] Polje (1,020‒1,080 m above sea level) is situated at the highest elevation of all Eastern Herzegovina poljes. Ćurčić (1915a) reported finding no fishes at Slato Polje, and no fishes are known from later literature or from museum collections. The Slato Polje is connected with Nevesinjsko Polje through a narrow valley that is now dry. The Nevesinjsko Polje, the largest polje in Eastern Herzegovina, has a surface area of 170 km² and is located at an elevation from 870 m to 800 m above sea level. The lowest point is Biograd Ponor, which is the terminus of the Zalomka River that starts at Raščelica near the Gatačko Polje. This river has a permanent flow only between Fojnica and Črni Kuk. Along the river bed downstream from Črni Kuk there are a lot of ponors. The most prominent leakage zone is in the Rilja section where the Zalomka is active only 213 days per year, on average (Milanović 1981, 2006). In the warm season almost the entire river bed of the Zalomka within the Nevesinjsko Polje is dry, and fishes are found in its upper section only. Only four species are known from there: Salmo sp., Squalius cf. squalus, Squalius svallize Heckel & Kner, 1858, Phoxinus sp. (PZ personal observations). Ćurčić (1915a) reported that Paraphoxinus metohienis was the most numerous species around Fojnica, but at present only Phoxinus sp. was found there by PZ. Further downstream, Telestes metohiensis occurs in those very short river sections that are adjacent to permanent springs such as Ljeskovik. This species also occurs in upper reaches of the Zavidolka River that temporarily flows to the Zalomka in the east from the Biograd Ponor (our data). Delminichthys ghetaldii is absent from the Nevesinjsko Polje and the Zalomka system.

Dabarsko Polje, about 20 km long and 1 to 3 km wide, is located close to the Nevesinjsko Polje but isolated from it. The Dabarsko Polje lies more than 400 m of elevation below the Nevesinjsko Polje. At present, the Dabarsko Polje is a closed basin without a possibility for surface runoff. All waters of the Dabarsko Polje catchment flow through underground karst conduits toward the springs of the Bregava River, though historically the Polje drained to the Bregava River canyon that is now dry. The lowest point is the Ponikva Ponor (471 m above sea level), the terminus of a single permanent stream in the polje, the Vrijeka River, which is only 2.5 km long (Milanović 1981, 2006). The Opačica River located in the northwestern part of the polje is longer but intermittent. Only two native species occur in Dabarsko Polje: Delminichthys ghetaldii and Telestes dabar (recorded earlier under the name Phoxinellus metohiensis) in Vrijeka and only Telestes dabar in Opačica (our data). Delminichthys (as Phoxinellus) ghetaldii was first recorded in Sušica and Ljelješnica cave springs by Ćurčić (1915a) and then confirmed by PZ’s findings in a stream flowing from the Ljelješnica Cave (Zupančič and Bogutskaya 2002) and in the Vrijeka. It is relatively less abundant in Vrijeka than Telestes dabar. A trout has been introduced into Vrijeka.

The small Lukavačko Polje (2.5 km²) is located at an elevation of 852–880 m east from the Dabarsko Polje. The two poljes are divided by about 400 m of elevation. Fatničko Polje is also a small closed basin (5.6 km²) located southeast from the Dabarsko Polje at a much lower elevation, 462–470 m above sea level. The Fatničko Polje is divided from the Dabarsko Polje by an extremely karstified limestone ridge which is about 2 km wide. The most prominent karst features of the Fatničko Polje are the Obod temporary spring and the Pasmica Ponor. About 85% to 90% of the Fatnicko Polje water flows to the Trebišnjica springs and 10% to 15% to the Bregava springs (Milanović 1981, 2006). Ćurčić (1915a, 1915b), Taler (1953a, 1953b), Sabioncello (1967) and Vuković (1977) reported Paraphoxinus metohiensis from the Lukavačko and Fatničko poljes. However, no extant samples confirm these reports. In 1998–2001, PZ found only Delminichthys ghetaldii in Fatničko Polje and no Delminichthys ghetaldii or Telestes metohiensis in the Lukavačko Polje (Zupančič and Bogutskaya 2002). No other data have been received since then.

Gatačko Polje (37.6 km²) consists of two geomorphologically and hydrogeologically interconnected units: Gatačko Polje itself and Small Gatačko Polje. The largest ponor zone is situated in Small Gatačko Polje along the 8 km long tectonic contact between flysch sediments and karstified limestone, from Srdevići to the Šabanov Ponor (936 m above sea level). The entire Gatačko Polje belongs to the catchment area of the Trebisnjica River, except a very small eastern part. The longest underground flow (35 km) in Eastern Herzegovina is between the Srdevići Ponor and the Trebisnjica Springs. The main flow in the Gatačko Polje is the Mušnica River with its tributary Gračanica. The Mušnica is formed by three streams, Vrba, Ulinjski Potok and Jasenički Potok. They flow from the Cemern and Lebršnik mountains. The Mušnica goes from the eastern to the western border of the polje and along its western border southwards before it completely sinks in the Šabanov Ponor. The flow of the Mušnica River re-appears in the Cerničko Polje where it is named the Ključka River. It originates in a large cave, Vilina Pećina and terminates about 300 m downstream in a ponor that has a recharge capacity of approximately 20 m³ s^−l (Milanović 2006). Telestes metohiensis (in Paraphoxinus or Phoxinellus by earlier authors), Phoxinus sp. and Alburnus neretvae Buj, Sanda et Perea 2010 are known to occur in Mušnica. Phoxinus sp. and, probably, Salmo sp. occur in Gračanica. Many literature sources (see in Zupančič and Bogutskaya 2002) reported Paraphoxinus metohiensis from the Gračanica River at Gacko, but we know of no extant samples. Only Telestes metohiensis was found (PZC) in short karstic streams of the Cerničko Polje.

Telestes metohiensis or close species are absent from other poljes except for the Konavosko Polje. This polje is located rather far in the south from poljes inhabited by Telestes metohiensis and Telestes dabar. The Konavosko Polje or Polje Konavliis the lowermost polje in the region (elevation 60 m above sea level) with surface of 48 km². It is developed along the most important overthrust of the entire dinaric karst region (“High Karst Overthrust”). The largest spring Konavoska Ljuta is located at this contact. In natural conditions it was a temporary flooded polje. Main flows are Ljuta and its tributaries Konavočica and Opačica. At present, a tunnel between the polje and the sea coast drains the polje (Milanović 2006). No recent records exist of a Telestes species in the Ljuta or other springs of the Konavosko Polje. However, we think that efforts are worth trying to find Telestes miloradi, a new species, described here from the Konavoska Ljuta before it is finally considered extinct. It is known that many species from Phoxinellus, Telestes and Delminichthys genera are able to enter karstic underground waters during droughts and dramatic water table level fluctuation (Milanović 2006; Jelić, 2008; Marčić et al. 2011). However, this phenomenon probably depends considerably on the degree of development, size and depth of caverns, siphonic lakes and pools of estavelles.

The ranges of Telestes metohiensis and Telestes dabar are extremely small at least during the dry season and in surface water bodies. The recognition of Telestes dabar as a distinct species will require its Red List evaluation and a re-evaluation of Telestes metohiensis (now considered as Vulnerable) because of the loss of a part of its former presumed range. Telestes dabar would probably deserve the Critically Endangered status because of its very restricted distribution (IUCN 2010). Both species are threatened by habitat destruction, in particular by construction of tunnels for the draining of poljes and controlling their inundations, lining of river beds to obstruct water flow into ponors and reversible communication with estavelles.

Telestes karsticus. PZC 577, 7, 547–750 mm SL, CROATIA: Sušik River at Tomići, Dobra River system (Danube drainage), 24 June 2005, coll. Zupančič.

Telestes metohiensis. All from BOSNIA AND HERZEGOVINA. Gatačko Polje: NMW 51176:3, lectotype, mm SL, 87.9 mm SL, ‘Mušica bei Imotski’ [misspelling, should be Mušnica River, Gatačko Polje; Imotski is probably an error because Steindachner (1901: 198) clearly indicated that the specimens had been received from karst waters and streams near Gacko, a town in the north of Gatačko Polje (43°09.4'N, 18°31.8'E); see also Zupančič and Bogutskaya 2002], 1899, coll. Redel, Sturani [Sturany]; NMW 51176:1–2, 72.2–82.5 mm SL, same data as holotype; NMW 12972, 1 paralectotype, 92.2 mm SL, same data as holotype; NMW 12973–75 (in one jar with 12972), 3 paralectotypes, 59.2–95.3 mm SL, same data as holotype; NMW 51172, 2 paralectotypes, 92.0–97.8 mm SL, same data as holotype; NMW 51174, 2 paralectotypes, 76.4–88.5 mm SL, same data as holotype; NMW 51175, 3 paralectotypes, 66.8–75.9 mm SL, same data as holotype; SMF 805, 2, 53.2–65.6 mm SL, Gacko; ZMH 15137, 7, 51.2–64.4 mm SL, Gacko, Herzegovina; Cerničko Polje: PZC 223, 9, 45.0–90.6 mm SL, source of Ključka River in Vilina Pečina (cave), 43°5.6'N, 18°29'E, 16 May 2003, coll. Zupančič; PZC 330, 9, 46.0–88.7 mm SL, same locality and collector, 23 May 2001; PZC 337, 4, 73.7–85.4 mm SL, same locality and collector, 20 Aug. 2000; PZC 368, 4, 49.0–62.2 mm SL, spring at Ključ, 43°5.6'N, 18°29.6'E, 23 May 2000, coll. Zupančič; PZC 503, 7, same locality and collector, 3 Aug. 2000. Nevesinjsko Polje: (NMW syntypes [now paralectotypes] of Paraphoxinus metohiensis labeled as Paraphoxinus affinis [handwritten by Steindachner; never published], nomen museale) NMW 9368–9372, 5, Zalomska [Zalomka River], 1896, coll. Hawelka; NMW 51088, 10, 47.6–57.9 mm SL, same data as above; NMW 51089, 10, 49.6–58.1 mm SL, same data as above; NMW 51092, 5, 51.9–65.5 mm SL, same data as above; NMW 51093, 8, 47.4–58.7 mm SL, same data as above; NMW 51094, 10, same data as above; NMW 51090, 5 (not labeled as syntypes of Paraphoxinus metohiensis though exclusion of these specimens from the type series is not evident from the original description), 47.6–57.9 mm SL, same data as above; NMW 51091, 4 (not labeled as syntypes, as above), 63.5–87.1 mm SL, same data as above; PZC 206, 3, 50.4–73.6 mm SL, Batuša River (Zalomka system), 43°19.3'N, 18°7.1'E, 9 May 2000, coll. Zupančič; PZC 355, 17, 39.6–63.8 mm SL, same locality and collector, 21 May 2001; PZC 356, 6, 53.2–66.1 mm SL, same locality and collector, 5 May 2000; PZC 312, 19, 50.1–79.8 mm SL, spring Ljeskovik in Zalomka River near Rast and Odžak, 43°12.1'N, 18°12.4'E, 21 May 2001, coll. Zupančič; PZC 313, 14, 49.1–78.7 mm SL, same locality and collector, 1 July 2002; PZC 567, 7, 45.1–86.2 mm SL, same locality and collector, 8 July 2011; PZC 358, 2, 38.2–42.0 mm SL, spring in Zalomka River at Budisavlje, 43°13.3'N, 18°13.1'E, 22 May 2011, coll. Zupančič; PZC 523, 15, 39.5–90.9 mm SL, Zovidolka [Zavodoka, Zovidolska] River at Udbine, 43°8.6'N, 18°14.7'E, 15 Sept. 2006, coll. Zupančič; PZC 293, 12, 49.1–99.2 mm SL, Zovidolka [Zavodoka, Zovidolska] River at Udbine, 43°8.6'N, 18°14.7'E, 29 Aug. 2006, coll. Zupančič; PZC 315, 17, 57.8–81.4 mm SL, same locality and collector, 16 July 2002; PZC 523, 15, 39.5–90.9 mm SL, same locality and collector, 15 Sept. 2006; PZC 524, 13, 39.5–90.9 mm SL, same locality and collector, 15 Sept. 2006; PZC 566, 45, same locality and collector, 8 July 2011.

Telestes polylepis. NMW 18931–41, 11, paralectotypes, 93.6–107.2 mm SL, CROATIA: Josefsthal [Josipdol], 1866; NMW 49713, 3, syntypes, 86.7–90.7 mm SL, CROATIA: Dobra River, 1866; NMW 49714–1, lectotype, 85.9 mm SL, CROATIA: Mresnitza [Mrežnica] River, 1866; NMW 49715, 2, paralectotypes, 80.8–84.1 mm SL, same data as lectotype.

Telestes turskyi. NMW 49629-1, lectotype, 129.5 mm SL, CROATIA: Čicola River [tributary of Krka], Dernis [Drniš] “Heckels Reise, 1840”; 17, paralectotypes, 55.3–102.3 mm SL.

Telestes ukliva. NMW 49639-1, lectotype, 85.0 mm SL, CROATIA: Sign “[aus der Cettina]”, “Heckels Reise, 1840”; NMW 49639-2 and 3, 2, 83.3–84.8 mm SL, same data as lectotype; NMW 49635, 3, paralectotypes, 58.0–75.8 mm SL, same data as lectotype; ZMH 15095, 1, CROATIA: Cetina.

Other extensive comparative material is listed in Zupančič and Bogutskaya (2002) and Bogutskaya and Zupančič (2003).