Bidessus anatolicus adiyaman, Aykut & Taşar & Fery, 2021

Aykut, Medeni, Taşar, Gani Erhan & Fery, Hans, 2021, Bidessus anatolicus adiyaman ssp. n. from Adıyaman province, southern Turkey (Coleoptera, Dytiscidae, Bidessini), Zootaxa 5027 (4), pp. 563-575 : 564-574

Bidessus anatolicus adiyaman ssp. n.

Type locality: Turkey, Adıyaman province, Gölbaşı district, near İnekli Lake , ca. 37.73N 37.50E (see Fig. 7 , red star, and Fig. 8 ) .

Type material: Holotype: ♂, “ 24.05.2017 Turkey / Adıyaman prov. / Gölbaşı district, near İnekli Lake / small puddles / 37.725N 37.500E / 875 m (Google-Earth), Taşar, G.E. leg.” [printed], “ Holotype / Bidessus / anatolicus adiyaman ssp. n. / Aykut, Taşar & Fery det. 2021” [red, printed] ( NMW) . Paratypes: 1 ♂, 4 ♀, 4 exs, same first la- bel as holotype; 1 ♂, 7 exs, “ 16.7.2013 Turkey / Adıyaman prov. / Gölbaşı district, near Azaplı Lake / small puddles / 37.744N 37.536E / 875 m ( Google-Earth ), Taşar, G.E. leg.” [printed]; all paratypes with a respective red paratype label ( CGT, CHF, CMA) .

Description of the holotype. Habitus very broadly oval, sides of elytra centrally appearing almost inflated ( Fig. 1a ); maximum width of body before midlength of elytra, here outline of body strongly curved; posteriorly, in weakly curved line converging to shortly rounded apex. Body outline at junction of pronotum and elytra with weak discontinuity because outline of elytra not following outline of pronotum, instead being slightly convex at base of elytra ( Figs 1a , 2a , 3a ). Dorsal surface shiny, brownish yellow on head and pronotum and dark brownish with brownish yellow pattern on elytra. Ventral surface ( Fig. 1c ) shiny and light brownish to large extent.

Dorsal surface: Head with anterior margin almost evenly rounded; posterior to margin with two distinct clypeal grooves above insertion of antennae; grooves connected by a weak impression, thus clypeus behind anterior margin appearing somewhat vaulted. Transverse occipital (cervical) line connecting hind margins of eyes ( Figs 1a , 3a ). Punctation generally sparse, behind occipital line absent; diameter of punctures on clypeus and frons equalling more or less that of meshes of reticulation, distance between punctures about 4–5x that of diameter, in clypeal grooves punctures denser; here and near eyes interspersed with a few very small punctures; alongside inner margin of eyes with distinct line of larger punctures. Reticulation generally polygonal, but behind anterior margin (on slightly vaulted part) and behind occipital line (on vertex) with very narrow elongate transverse meshes. Surface brownish yellow with diffusely delimited more brownish areas above insertion of antennae and near eyes. First four antenno- meres brownish yellow, others brownish. Setation on dorsal surface almost imperceptible, only faintly recognisable in SEM photographs ( Figs 2a , 3a ).

Pronotum with distinct basal striae ( Figs 1a , 3a ), reaching anteriad beyond mid-length of pronotum; between striae not impressed; lateral sides of pronotum almost straight in posterior 3/4, converging anteriad, near anterior corners curved inwards; margins rimmed, rim near anterior corners becoming narrower. Punctation between striae very sparse and fine, only before base with coarser punctures, these more numerous and larger near striae; punctures between striae and lateral sides also sparse, but larger than finer punctures between striae; narrow stripe behind anterior margin with several small and densely arranged punctures. Reticulation on pronotum absent. Surface brownish yellow, lighter (more yellowish) than on head. Between striae before base dark brownish, in particular near striae.

Elytra with distinct basal striae ( Figs 1a , 2a , 3a ); these somewhat longer than pronotal striae, not reaching until midlength of elytra; sutural puncture lines present, posteriad reaching beyond midlength of elytra. Sides of elytra distinctly projecting over faintly rimmed side margin of elytra; thus, in dorsal view actual side margin only visible at shoulders and before apex. In lateral view elytral margin moderately ascending towards shoulders; epipleuron not visible until shoulders. Punctation between discal striae rather dense, distance between punctures more or less equal to their diameter, punctures more or less as large as punctures near pronotal striae; punctures between striae and elytral outline smaller and sparser. Reticulation absent on entire elytra. Surface blackish brown with three yellow bands; one band before midlength of elytra, second band short behind midlength, and third band short before apex; all bands interrupted medially ( Fig. 1a ).

Ventral surface: Colour and reticulation: Predominantly brownish ( Fig. 1c ); head, prosternum, propleuron, hypomeron (= pronotal epipleuron), elytral epipleuron and legs more yellowish brown; surface shiny. Reticulation only on pro- and mesotibiae as well as on pro- and mesofemora recognisable, else absent. Setation generally sparse, on most parts of surface absent (cf. Figs 1c , 2b ).

Head: Gula laterally with very few punctures. Genae with crease behind eyes, anteriorly with line of few small punctures. First and second antennomeres relatively long, third shorter and distinctly narrower, fourth much shorter than third, more or less as long as wide, fifth to ninth distinctly larger than fourth, tenth again narrower, eleventh slender and longer ( Figs 2b , 3b ).

Prothorax: Prosternum anteromedially (before procoxae) somewhat vaulted and coarsely sculptured; laterally (before propleuron) smooth and shiny, without punctures. Hypomeron in anterior half laterally narrowly flattened, becoming broader anteriad; flat region with some coarse lengthy punctures and long setae ( Fig. 3b ); rest of hypomeron and propleuron smooth and shiny. Prosternal column ascending posteriad (as viewed if beetle turned upside down), between procoxae with a few transverse ridges. Prosternal process weakly inclined, broadly lanceolate, apex broadly rounded ( Fig. 2b ); with distinct broad longitudinal parallel-sided furrow; furrow formed by a few very coarse and closely arranged punctures, sides of furrow strongly rimmed; right and left of furrow process strongly descending. Apex of process reaching between mesocoxae and here touching anteromedial process of metaventrite.

Pterothorax: Metepisternum triangular, before anterior margin deeply impressed and with a few coarse punctures. Anteromedial process of metaventrite broad (more or less 1/3 of maximum width of mesocoxa), anteriorly reaching beyond middle of mesocoxae; distally with short broad furrow for reception of prosternal process. Suture between metaventrite and metacoxal plates almost imperceptible; metaventrite behind mesocoxae strongly rimmed; directly behind rim with line of punctures; rim with very distinct backwards directed extension, reaching anterior part of metacoxal plate and separating central part of metaventrite from its lateral wing. Metaventrite right and left of midline with line of coarse punctures, lines diverging posteriad, reaching until anterior margin of metacoxal plates; another line of coarse punctures alongside border to metacoxal plates. Metacoxal plates centrally with sev- eral coarse punctures. Metacoxal lines diverging anteriad, relatively short, maximum distance between lines about as long as midline; some coarse punctures alongside metacoxal lines. Posterior margin of metacoxal processes obliquely incised, each process postero-laterally without lobes, and thus not covering bases of metatrochanters ( Fig. 2b ).

Epipleura anteriorly rather broad (broader than mesotibiae), becoming narrower at level of first abdominal ven- trite ( Fig. 1c , 2b ); with some small punctures alongside margins; without transverse carina at humeral angle ( Fig. 2b ). Elytral surface between lateral outline and actual margin of elytra (alongside epipleura, where sides of elytra projecting over rimmed margin; see Fig. 1c ) with only very few punctures except a line of small punctures alongside actual margin of elytra ( Fig. 2b ). Notes: According to Miller & Bergsten (2016: 219) most genera of Bidessini have the metacoxae fused to the first visible abdominal ventrite; this character was not checked as it would have damaged a specimen. We can, however, state that the suture between the two structures is easily visible (see Figs 1c , 2b ).

Abdomen ( Fig. 2b ) with first three ventrites rigidly connected; first and second laterally with coarse punctures, second behind metacoxal processes with several small setiferous punctures; third to fifth without large punctures but with several sparsely distributed small setiferous punctures, this same type of puncture being denser on last ventrite. Fourth and fifth ventrite centrally with a tuft of long setae (which can easily be rubbed off). Apex of last ventrite weakly pointed.

Legs: Protibiae broadened distally; inner margin curved. First two pro- and mesotarsomeres with distally broad- ly enlarged sucking setae ( Fig. 4a ). Protarsal claws simple. Metatibiae slender and slightly curved. First metatarso- mere slightly shorter than second and third tarsomere together.

Measurements: TL: 1.65–1.8 mm (1.75 mm), MW: 1.0– 1.1 mm (1.05 mm), MW prot: 0.8–0.85 mm (0.85), TL/ MW: 1.62–1.67 (1.67), MW/MW prot: 1.26–1.34 (1.27); n = 8 (values of the holotype in brackets). For comparison values of the nominotypical ssp.: TL: 1.65–1.7 mm, MW: 0.95–1.0 mm, MW prot: 0.75–0.8 m, TL/MW: 1.68–1.76, MW/MW prot: 1.25–1.31; n = 6.

Males: median lobe in ventral and lateral view as in Figs 5a, 5b ; parameres two-segmented ( Fig. 5c ).

Females: Gonocoxosternum and gonocoxae as in Figs 6a, 6b . First three pro- and mesotarsomeres slightly narrower than in males and without distinctly enlarged sucking setae ( Fig. 4b ); other external morphological differences to males not found.

Variability: Apart from size the only variation observed was in the elytral pattern: in a few specimens the yel- lowish bands are somewhat more developed than in the holotype and the first band is connected with the second band by a narrow longitudinal strip (more or less in prolongation of the elytral striae).

Collecting circumstances: On 24.5.2017 paratypes of the new taxon were found in small puddles near the İnekli Lake (altitude according to Google Earth ca. 877 m) together with three specimens of Bidessus exornatus (Reiche & Saulcy, 1855) . The puddles result from peat cutting which leaves holes that fill with water (see Figs 8a–8d ). The other collecting site (near Azaplı Lake; altitude ca. 878 m) is very similar and the distance between both is only about 3.8 km; both sites are connected by a small river slowly running in marshy ground (largely used for peat cutting) and a man-made canal connecting both lakes.

Differential diagnosis. We compared specimens of the new taxon with the following specimens of the other subspecies of B. anatolicus (all specimens in CHF, except that from Kızılot: CAP):

- Bidessus a. anatolicus : 6 exs from near Kumluca ( Fig. 7 , green circle 1), 28.7.1983, Wewalka leg.; 1 ex. from near Kızılot ( Fig. 7 , green circle 3), VII. 2008, Pütz leg.; the type locality of this subspecies is near Antalya, ca. 36.89N 30.71E, 26.5.1968, Wewalka leg. ( Fig. 7 , green circle 2) .

- Bidessus a. kadmos: 2 exs from Park Ha’ Yarden, Israel, 12.4.1986, Jäch leg.; 1 ex. En Jezer , Jordan delta, Israel, 27.8.1985 , Jäch leg.; 1 ex. from En Jalabina , north of Lake Tiberias, Israel, 16.7.1985 , Jäch leg. (all localities near yellow circle 4 in Fig. 7 ).

- Bidessus a. phoenix: 1 ex. from Or Aguira, S Haifa, Israel, 5.8.1985, Jäch leg. ( Fig. 7 , blue circle 5) ; 1 ex. from En Tamar , Dead Sea area, Israel, 24.4.1985, Jäch leg. ( Fig. 7 , blue circle 6) .

Differences between the new subspecies and B. a. kadmos and B. a. phoenix are easily recognisable—the latter two have a distinctly less broadened habitus and are even more slender than B. a. anatolicus (see figs 2a–2c in Wewalka 1989); they need not to be dealt with here in further detail.

Differences between the new ssp. and the nominotypical ssp. are present, but are less obvious. Both can be best separated by the body shape which is considerably broader in the new ssp. and the sides of elytra centrally appear much more inflated (compare Figs 1b and 1b ). This is well reflected by the ratios “total length/maximum width” which differ considerably: 1.62–1.67 in the new ssp. and 1.68–1.74 in the nominotypical ssp. The maximum width of body is in both ssp. situated before the midlength of elytra, but the outline of the body is here more strongly curved in the new ssp. In B. a. anatolicus the sutural lines are less impressed, the punctures on the disc (mainly between sutural line and stria) are less coarse (in B. a. kadmos and B. a. phoenix lines still less impressed and punctures less coarse). In B. a. anatolicus the sides of of the pronotum are less converging forwards and form with the sides of the elytra an almost straight line and, thus, the discontinuity of the body outline at the junction of pronotum and elytra is negligible.

The male genitalia also show differences. Firstly, however, some notes on the figures of the median lobe in We- walka (1972 and 1989) are necessary. The figures of the ventral view of the median lobe of the new ssp. ( Fig. 5a ) and the nominotypical ssp. ( Fig. 5d ; adopted from fig. 2 in Wewalka 1972) show considerable differences in the shape of the apex (see also the median lobe in ventral view of B. a. phoenix in Wewalka 1989: 150, fig. 3a). However, this discrepancy can be easily resolved: if the median lobe is oriented as in Fig. 5b and is observed from the right side (arrow) then a ventral view results which is given in Fig. 5a . If, however, the median lobe is oriented as in Figs 5e or 5f and is observed from the right side (arrow) then the apex of the lobe is hidden and it results a broadly rounded apex as given in Fig. 5d . Notes: Figs 5f and 5g belong to a specimen of B. a. anatolicus from Kumluca (see above). Having noted these special circumstances, we can give that in the new ssp. the dorsal outline of the median lobe in lateral view is almost evenly curved at the base and distinctly less bent ( Fig. 5b ). Additionally, the lobe is more curved in distal half and the apex slightly bent dorsally. Differences in ventral view are less obvious. The paramere ( Fig. 5c ) is somewhat broader in the new ssp. (for B. a. anotolicus see Figs 5g and 5h ); however, we suspect that this feature cannot be used for a safe separation of the two taxa.

Finally, our present knowledge of the distribution of the two ssp. indicates that B. a. anatolicus is a more coastal taxon (altitudes less than 300 m) whilst the new ssp. was found far away from the coast and at much greater altitudes (almost 900 m).

Figures

FIGURES 1a–1c. a, c: Habitus of Bidessus anatolicus adiyaman ssp. n. (holotype): (a) in dorsal view; (c) in ventral view (left hind-leg and last abdominal ventrites removed); b: Habitus of Bidessus anatolicus anatolicus Wewalka.

FIGURES 2a–2b. Habitus of Bidessus anatolicus adiyaman ssp. n. (paratype): (a) in dorsal view; (b) in ventral view.

FIGURES 3a–3b. Bidessus anatolicus adiyaman ssp. n. (paratype): (a) oblique view on head, pronotum and anterior part of elytra; (b) ventral view on parts of head and prosternum (propleuron and hypomeron).

FIGURES 4a–4b. Ventral view on protarsomeres of Bidessus anatolicus adiyaman ssp. n. (paratypes): (a) male; (b) female.

FIGURES 5a–5h. Male genitalia of: a–c: Bidessus anatolicus adiyaman ssp. n. (holotype): (a) median lobe in ventral view; (b) median lobe in lateral view; (c) left paramere; d–h: Bidessus a. anatolicus: (d) median lobe in ventral view; (e) median lobe in lateral view; (h) left paramere (all adopted from Wewalka 1972: 73); f, g: Bidessus a. anatolicus (specimen from Kumluca): (f) median lobe in lateral view; (h) left paramere (arrows indicate direction of view on ventral surface of median lobe).

FIGURES 6a–6b. Bidessus anatolicus adiyaman ssp. n. (female paratype): (a) gonocoxosternum; (b) gonocoxae.

FIGURE 7. Distribution of Bidessus anatolicus adiyaman ssp. n. (red star), Bidessus a. anatolicus (green circles), Bidessus a. kadmos (yellow circle) and Bidessus a. phoenix (blue circles) (map adopted from Microsoft Encarta World Atlas 2000).

FIGURES 8a–8d. Around the type locality of Bidessus anatolicus adiyaman ssp. n. at the northern part of the İnekli Lake).