Takobia shughnonica Sroka & Gattolliat, 2021

Sroka, Pavel, Yanai, Zohar, Palatov, Dmitry & Gattolliat, Jean-Luc, 2021, Contribution to the knowledge of the genus Takobia Novikova & Kluge, 1987 (Ephemeroptera, Baetidae) in Central Asia, ZooKeys 1071, pp. 127-154 : 127

Takobia shughnonica Sroka & Gattolliat sp. nov.

Figs 1C, F ; 7 , 8

Material examined.

Holotype. mature female nymph (in EtOH): Tajikistan, Roshtqal'a District . Spring near Sezhd village, 2966 m a.s.l., 37°12.65'N, 72°04.44'E, 2.7.2016, Palatov leg., locality code: 243 Tj . Paratypes. 39 nymphs (33 in EtOH, 2 on slides with HydroMatrix mounting medium, 2 on SEM stubs, 2 DNA voucher specimens): same data as holotype. 13 nymphs (in EtOH): Tajikistan, Shughnon District , unnamed river, right tributary of Gunt Riv., ca. 500 m S from Dehmiyona village , 2700 m a.s.l., 37°42.88'N, 71°53.61'E, 23.5.2012, Palatov leg., locality code: 15Tj. 28 nymphs (in EtOH): Tajikistan, Shughnon District . Vuzh-dara Riv., 3 km upstream Dehmiyona village, 2500 m a.s.l., 37°42.47'N, 71°57.29'E, 24.5.2012, Palatov leg., locality code: 31Tj. 2 nymphs (in EtOH): Tajikistan, Shughnon District , unnamed river, tributary of Gunt Riv. near Shitam village , 2500 m a.s.l., 37°44.30'N, 72°2.19'E, 31.5.2012, Palatov leg., locality code: 76Tj. 54 nymphs (in EtOH): Tajikistan, Shughnon District , stream on the slope of Gunt Riv. valley , ca. 3 km downstream from Ver village, 2875 m a.s.l., 37°43.27'N, 72°1.85'E, 5.6.2012, Palatov leg., locality code: 93Tj. 1 nymph (in EtOH): Tajikistan, Shughnon District , unnamed river near Tong village , 2480 m a.s.l., 37°35.78'N, 71°43.79'E, 8.6.2012, Palatov leg., locality code: 113Tj. 1 nymph (in EtOH): Tajikistan, Shughnon District, spring on slope of the Bogev-dara gorge. 2578 m a.s.l., 37°31.13'N, 71°41.98'E, 9.6.2012, Palatov leg., locality code: 120Tj. 17 nymphs (in EtOH): Tajikistan, Shughnon District, right source of the Bogev-dara Riv., 2928 m a.s.l., 37°29.89'N, 71°44.36'E, 10.6.2012, Palatov leg., locality code: 123 Tj .

Holotype and 34 paratypes are deposited in IECA, 5 paratypes including DNA voucher specimens are deposited in MZL, 118 paratypes are deposited in ZMMU. The inventory numbers for the MZL specimens are GBIFCH 00829875 for the specimens in alcohol, GBIFCH00895421 and GBIFCH00895422 for the specimens used for DNA extraction. GenBank accession numbers in Table 1 .

Differential diagnosis.

Takobia shughnonica sp. nov. can be separated from other related species by the combination of the following characters: 1) maxillary palp highly developed with the segment I straight and segment II slightly sinusoidal; 2) labrum dorsally covered with numerous setae, one central and two lateral forming the traditional disto-lateral arc of setae; 3) right prostheca reduced, basally bifid; 4) labial palp segment III symmetrical and almost conical; 5) claw with one row of teeth increasing in size toward the apex, subequal to 1/3 of corresponding tarsus; 6) paraproct with a short bent prolongation.

Description of nymph.

Length. Female body 6.4-7.4 mm; cerci 4.2-5.1 mm; median caudal filament 3.4-4.2 mm; male body 5.6-6.6 mm; cerci 3.5-3.6 mm; median caudal filament 2.7-3.0 mm.

Coloration and texture. General coloration brown (Fig. 1C, F ). Head uniformly brown, darker in areas between compound eyes and between ocelli. Turbinate eyes in male nymphs dark brown. Legs light brown with patches of pale whitish color on lateral margin of femora. Thorax dorsally brown without markings or pattern, thin pale longitudinal line medially. Abdominal tergites I-VIII medium brown, lateral portions slightly paler. Tergites IX and X pale brown. In some specimens, two pale dots observable submedially on tergites VII and VIII. Abdominal sternites II-XIII light brown, sternite IX slightly paler, sternite I whitish. Gill plates whitish with dark margins. Cerci ecru to light brown without bands or pattern. Surface of body shagreened, most pronounced on head capsule and thorax (Fig. 8C ).

Head. Antennae close to each other, with a narrow interantennal carina; scape and pedicel with V-shaped scale insertions and sparse setae. Dorsal surface of labrum (Fig. 7A ) evenly covered with numerous long setae and scattered small fine setae, in place of distolateral arc of prominent setae only two long setae, one promiment long seta submedially, almost no setae present along midline; ventral surface with row of submarginal small, pointed setae laterally; distal margin fringed with ca. 20-23 short, followed by 13-15 long, feathered setae. Right mandible (Figs 7C, D ; 8A ) with sparse fine setae; incisors composed of eight apically pointed denticles (in nymphs long after molting, denticles become worn out and rounded), outer and inner incisor group with four denticles each (outermost denticle of inner incisor group often worn out and indistinct); row of short fine setae along inner margin of incisors present; prostheca inserted on elevated projection, reduced, consisting of two prominent setae, accompanied by several shorter ones, all conspicuously feathered; margin between prostheca and mola with tuft of fringed setae. Left mandible (Fig. 7B, E ) with sparse fine setae; incisors composed of seven apically rounded denticles, outer and inner incisor group not distinctly separated; prostheca with denticles and comb-shaped structure; margin between prostheca and mola with short, fringed setae. Hypopharynx apically covered with thin setae; lingua with central small protuberance; superlingua of approximately same length as lingua. Maxilla (Fig. 7F ) with incisors composed of three elongated and curved teeth; crown with two rows of setae, ventral one with only small setae, dorsal row with three long stout dentisetae (apical dentiseta similar to maxillary teeth, relatively broad); maxillary palp very long, nearly 2 × longer than galeolacinia, two-segmented, length of segment II approximately equal to segment I; segment I straight, not distinctly widened apically; segment II slightly sinusoidal, apically rounded; both segments with numerous thin setae. Labium (Fig. 7G ) with glossae subequal to paraglossae; both inner and outer margins of glossae with row of pointed setae, dorsal surface of glossae with well-defined group of fine setae subapically; ventral surface of glossae with group of long setae extending from basal part of glossa along its inner margin to apex; paraglossae with two rows of long, stout setae apically; labial palp three-segmented; segment I slightly shorter than segments II and III combined; segment II with very small medioapical protuberance and irregular dorsal oblique row of ca. seven or eight long setae; segment III symmetrical, elongated, narrowing towards apex, without any projection; all segments of labial palp with hair-like setae, present only sparsely on segments I and II, most dense on ventral surface of segment III; several distinct stout pointed setae present along inner margin of segment III.

Thorax. Forelegs (Fig. 7H ). Trochanter with ca. six marginal spine-like setae. Femur dorsally with one row of 18-23 medium, stout setae; additionally, dorsoapical setal patch formed by another 7-9 stout, medium setae; ventral margin with numerous stout, pointed short setae, some of these setae on lateral margin subparallel to ventral margin, villopore absent; lateral margin with occasional short hair-like setae and V-shaped scale bases with scales (not figured in Fig. 7H ). Tibia with many setae along ventral margin and group of setae apically; fewer setae also elsewhere on surface of tibiae and along dorsal margin; tibiopatellar suture present; lateral margins with scales and numerous scale bases. Tarsus with row of ca. 25-30 small, pointed setae on ventral margin; lateral margins with numerous scale bases. Tarsal claw (Fig. 8B ) hooked, with single row of 12-15 well developed teeth, increasing in size distally; apical setae present, very minute; length of tarsal claw ca. 1/3 of tarsus length; Mid and hindleg (Fig. 7I, J ) similar to foreleg, except setae along ventral margin of femora, less robust and more scarce in mid and hindlegs compared to forelegs. Hindwing pads present.

Abdomen. Tergites (Fig. 8D ) slightly shagreened, with numerous V-shaped scale bases, scales (rounded apically), and thin hair-like setae; distal margin of tergite I without triangular spines, tergites II-X with well-developed row of triangular spines, slightly longer than wide; row of triangular spines on tergite X not interrupted in middle. Sternites with scales, scale bases and setae similar to tergites; distal margin of sternites IV-IX with row of triangular spines, this row interrupted in middle in sternite IV and also interrupted in places of emerging gonostyli in male nymphs; triangular spines in lateral parts of sternite generally narrower than in central part of same sternite. Gills (Fig. 7K-Q ) on segments I-VII, slightly asymmetrical, margins serrated mainly in distal 1/2, dorsal surface with scales and scale bases submarginally, tracheation faintly visible; gill I oval-shaped, rounded apically, ca. 3 × wider than long; gills II to VII widened in distal portion, pointed apically, ca. 2.1-2.6 × wider than long. Paraproct (Fig. 8F ) with abundant scales and scale bases (of same shape as on tergites and sternites); distinct prolongation bent dorsally; paraproct margin with ca. 3-5 triangular spines laterally from prolongation and numerous slightly smaller spines medially from prolongation; prolongation margined with ca. 15 elongated medium spines, with only minor spines on ventral surface; cercotractor with scales and scale bases, margin with triangular spines.

Etymology.

The species is named Takobia shughnonica after the local ethnicity and the historical region of Shughnon, where the species was discovered.

Distribution and ecology.

So far known from several localities in the Pamir Mountains (Tajikistan). Nymphs were collected from stones and boulders sometimes covered with algae and moss in mountain springs and streams located at altitudes of 2480-2928 m a.s.l., at flow rates of 0.5-1.0 m/s, with water temperatures ca. 10-12°C (Fig. 9C-E ).

Figures

Figure 1. Takobia nymphs, habitus photographs A T. maxillare, habitus in dorsal view B T. sinusopalpata sp. nov., habitus in dorsal view C T. shughnonica sp. nov., habitus in dorsal view D T. maxillare, habitus in lateral view E T. sinusopalpata sp. nov., habitus in lateral view F T. shughnonica sp. nov., habitus in lateral view. Scale bar: 1 mm.

Figure 7. Takobia shughnonica sp. nov., nymph A labrum (left side dorsal view, right side ventral view) B left mandible (dorsal view) C right mandible (dorsal view) D right mandible, detail of incisors and prostheca (dorsal view) E left mandible, detail of incisors and prostheca (dorsal view) F maxilla (dorsal view) G labium (left side ventral view, right side dorsal view) H foreleg (dorsal view) I middle leg (dorsal view) J hind leg (dorsal view) K-Q gill plates.

Figure 8. Takobia shughnonica sp. nov., nymph A detail of right prostheca B tarsal claw C pronotum texture D posterior margin of abdominal tergite VI E posterior margin of abdominal sternite VI F paraproct. Scale bars: 10 μm (A); 100 μm (B, F); 50 μm (C-E).

Figure 9. Takobia spp., examples of habitats A locality of T. sinusopalpata sp. nov. (Otmek Riv., locality code: 65 Kyrg) B type locality of T. sinusopalpata sp. nov. (left tributary of the Adygene Riv., code: 17 Kyrg) C locality of T. shughnonica sp. nov. (right tributary of Gunt Riv., code: 15 Tj) D locality of T. shughnonica sp. nov. (stream on the slope of Gunt Riv. valley, code: 93 Tj) E locality of T. shughnonica sp. nov. (right source of the Bogev-dara Riv., code: 123 Tj).