Leptopus gakalae, Khazaei & Polhemus & Tahami, 2020

Khazaei, Zohreh, Polhemus, Dan A. & Tahami, Mohadeseh S., 2020, A new species of Leptopus (Heteroptera: Leptopodidae) from caves in Iran, with notes on other cavernicolous Iranian Heteroptera, Zootaxa 4763 (2), pp. 246-258 : 248-251

Leptopus gakalae n. sp.

( Figs. 2–5 )

Type material examined. Holotype, male, IRAN, Kohgiluyeh and Boyer-Ahmad Prov., Gakal Cave, 30°18’44”N, 51°9’28”E, 1100 m elev., 18 October 2015, Zohreh Khazaei ( BPBM) . Paratypes: IRAN, Kohgiluyeh and Boyer- Ahmad Prov.: 4 males, 5 females (one apterous), same data as holotype (1 female BPBM, remainder ZM-CBSU).

Description. Winged male: Body length (from head to apical tip of forewings) 2.5–3.5 mm; maximum width (across hemelytra) 1.0 mm ( Fig. 1 ).

General coloration pale whitish-tan, with thorax and broad maculae on hemelytra yellowish-brown, appendages pale ( Fig. 1 ); entire dorsal surface bearing moderately long, erect, stout, pale setae.

Structural characters: Head length 0.60, width across eyes 0.90, brown; frons declivent, nearly vertical, bearing three long, stout, gold setae basally at junction with vertex; width of vertex 0.50, with semi-spherical protuberance medially bearing 2 ocelli; a pair (1 + 1) of whitish setae set at a short distance from each other immediately behind ocelli; two whitish setae anteriorly on midline of vertex; suture present at midline of vertex next to mid-projection of vertex; clypeus yellowish; posteroventral margins dark; three long, whitish spines ventrally to either side of longitudinal midline on post-genal sclerites. Eyes red, prominent, semi-circular, bearing short, pale ocular setae, inner margins bi-concave. Rostrum attaining fore coxae, segment II yellowish, longest, with two pairs (2+2) of long spines located on tubercles ( Fig. 2 ); segment III yellowish, with two pairs of long tuberculate spines; segment IV shortest, dark brown at apex. Antennae with segment I short, 0.4× as long as segment II, thickened in the middle and narrowed proximally and apically; segment II 1.25× length of segment III, yellowish, clavate, and thickened apically; segments III and IV dark brown, segment IV 0.28× as long as segment III, with recumbent dark brown setae; lengths of segments I–IV = 0.15, 0.40, 0.80, 0.45.

Pronotum length 0.60, maximum width 0.75, yellowish-brown, punctate, with scattered spines; pronotum partitioned into anterior and posterior parts near middle by prominent transverse furrow; anterior lobe with longitudinal furrow along midline, separating calli, each callus with two small angular processes; lateral margins very narrowly explanate, with scattered erect, spine-like pale brown setae. Scutellum length 0.25, width 0.35, brown with a pale tip, bearing a pair (1+1) of erect, spine-like pale brown setae on either side of midline; central section depressed.

Elytra coleopteriform, completely sclerotized and lacking membrane; clavus and corium well defined, punctate, set with scattered erect, spine-like, pale brown setae, ground color whitish-tan, with prominent X-shaped, yellowish-brown fascia traversing center of corium ( Fig. 2 ); hind wings reduced, half as long as forewings; basal section of hemelytra inside of medial fracture raised; hemelytral margin narrowly explanate, embolium only very weakly expanded.

Abdomen brown dorsally, with 7 visible segments including medio- and laterotergites.

Venter with mesosternum and metasternum brown, tumescent; abdomen yellowish-brown, bearing sparse inconspicuous pale setae.

Legs yellowish-white with a preapical dark spot on femora; foretibia with three spines dorsally originating from tubercles ( Fig. 3 ), apical 3 rd spine shorter, plus three light brown spines ventrally, the middle one longer; fore femur yellowish-white with a preapical dark spot, four fine tuberculate spines dorsally, the proximal one shorter, five tuberculate spines ventrally, the proximal 2 nd one and the apical 5 th one shorter; middle and hind femora yellowishwhite with a preapical dark spot; tarsi yellowish-white, middle and hind tarsi brown apically, claws also brown; apices of fore tibia and fore tarsus brown, fore tarsus also bearing long pale setae. Lengths of leg segments as follows: fore femur–tibia–tarsomere 1– tarsomere 2–tarsomere 3 = 0.85/0.85/0.05/0.10/0.10; middle femur–tibia–tarsomere 1– tarsomere 2–tarsomere 3 = 0.75/1.00/0.05/0.10/0.15; hind femur–tibia– tarsomere 1– tarsomere 2– tarsomere 3 = 0.95/1.45/0.05/0.15/ 0.20.

Male genitalia with parameres symmetrical, elongate, apices broadly rounded ( Fig. 4 ).

Winged female: Similar to winged male in general structure and coloration ( Fig. 2 ); length 3.20, maximum width 1.20.

Etymology. The specific name “gakalae” refers to the Gakal Cave, where the type series was collected.

Remarks. Our new species clearly belongs to the clade containing Leptopus , Leptopoides J. Polhemus & D. Polhemus, 1991 , and Patapius Horvath, 1912 , due to the presence of stout spines on both of the first two visible rostral segments (J. Polhemus & D. Polhemus 1991, Linnavuori & van Harten 2002). It runs to the genus Leptopus in the key of J. Polhemus & D. Polhemus (1991), based on the presence of short, slender ocular setae, and the presence of two divergent rows of stout spines on the fore tibia ( Fig. 3 ).

Seven species of Leptopodidae have been previously recorded from Iran ( Hoberlandt 1983, Schuh et al. 1987, Ghahari et al. 2013): Erianotus lanosus Dufour, 1834 ; Patapius sentus Drake & Hoberlandt, 1951 ; Patapius spinosus (Rossi, 1790) ; Valleriola assouanensis (Costa, 1875) ; Leptopus decus Drake, 1955 ; Leptopus hispanus Rambur, 1840 ; and Leptopus marmoratus (Goeze, 1778) . The Iranian records for L. marmoratus provided by Sakenin et al. (2010) and Samin et al. (2011) have, however, been called into question (see subsequent discussion under that species). Most of the above species records also lack information on ecological context, although Patapius spinosus was noted as having been taken from the margins of a small stream near Ramhormoz in Khuzestan ( Linnavuori 2009).

In addition to the two widespread species L. hispanus Rambur ( Fig. 7 ) and L. marmoratus ( Fig. 10 ), which occur primarily to the west of Iran from southern Europe through the Balkans to trans-Caucasia, three additional species, L. travancorensis Distant , L. scitulus Drake ( Fig. 8 ) and L. decus Drake , have been described from the western areas of India; the latter taxon was described from Punjab, and its range extends westward to the Sistan & Baluchestan Province of Iran. Given that no overall revision of Leptopodidae has been undertaken since that of Horváth (1911), which is now taxonomically incomplete, it has been necessary to accurately determine that our new species from Iranian caves is indeed discrete from those previously described. The second author examined specimens of all the taxa noted above during a visit to the collections of the Smithsonian Institution in Washington, DC, and was able to verify that L. gakalae is distinct from all of them (see key).

Another species of Leptopus , L. markusiki Vinakurov, 2012 , has been described from moderate elevation in the Himalayan foothills of Himanchal Pradesh state ( Vinokurov 2012) but has not been examined by the authors. However based on the figures provided by Vinokurov (2012), this species is easily separated from L. gakalae by its blotched rather than fasciate color pattern on the hemelytra, and the distinctive, club-like structure of the male paramere.

Habitat notes. Gakal Cave is located in the Zagros Mountains woodland, where Persian oak is the dominant tree ( Fig. 1 ). In the dark zone of the cave, there is a puddle of water supplied with a spring and fed by water dripping down into the puddle from the cave’s ceiling ( Fig. 6 ). The Zohreh River is the nearest surface water feature, lying about 10 km east of the cave. The specimens were collected in the entrance zone, where they could be seen clearly with the amount of sunlight coming in. The leptopodids were observed adjacent to a population of Collembola, which may provide a food source.

Figures

FIGURE 1. Locations of caves from which aquatic and semi-aquatic Heteroptera have been collected in Iran.

FIGURE 2. Leptopus gakalae n. sp., female, dorsal habitus photo. Specimen from Gakal Cave, Iran.

FIGURE 3. Leptopus gakalae, male eye and foreleg, ventral view.

FIGURE 4. Leptopus gakalae n. sp., male abdomen, ventral view, showing symmetrical parameres.

FIGURE 5. Leptopus gakalae n. sp., male paramere.

FIGURE 6. Photograph of the interior of Gakal Cave, type-locality for Leptopus gakalae n. sp.

FIGURE 10. Leptopus marmoratus Goeze, 1778, dorsal habitus photograph, appendages omitted. Specimen from agricultural quarantine intercept at Baltimore, Maryland, USA.

FIGURES 7, 8. Leptopus species, dorsal habitus photos, appendages omitted. 7. Leptopus hispanus Rambur, 1840, specimen from Cyprus. 8. Leptopus scitulus Drake, 1954, specimen from India, Dehra Dun.X