Ctenolepisma (Sceletolepisma) kermanshanum Molero, Kahrarian & Gaju

Kahrarian, Morteza, Molero, Rafael & Gaju, Miquel, 2016, The genus Ctenolepisma (Zygentoma: Lepismatidae) in Western Iran, with description of three new species, Zootaxa 4093 (2), pp. 217-230 : 225-228

Ctenolepisma (Sceletolepisma) kermanshanum Molero, Kahrarian & Gaju , new species

Figs. 21‒30

Type material. Holotype: one male from Bistoon Mountain, under rocks, (N34°23’ E47°26’,elev. 1116 m), Harsin County, Kermanshah, Iran, June, 2013, mounted on a slide, deposited in MNCN, Cat. Types N. 2607. Paratype: one male from the same sample, deposited in UCO (Ref. Z2503).

Description. Body length 5.5 mm in the holotype, 5.1 mm in the paratype. Body subcylindrical; thorax very slightly wider than the abdomen base, width 1.5 mm). Epidermic pigment light brownish in specimens preserved in alcohol, more intense in appendages. Macrosetae hyaline or light yellowish to brown. Dorsal scales with dark pigment. Some scales of the lateral parts of nota are larger than the others, and some show an indentation corresponding with bare spots.

Eyes and setation of the head typical of the genus. Antennae broken (maximum length preserved 2.4 mm). Maxillary palp with long articles, the distal article 4.5‒5 times longer than wide and as long as the penultimate segment ( Fig. 21 ). Apical article of the labial palp 1.1 times longer than wide, with three sensory papillae arranged in a single row ( Fig. 22 ). A group of basiconic sensilla are visible in the outer side of the apical article; one more basal, one more distal and three in a row, one sensillum larger, the other two sharing area of insertion.

Median brush of the anterior margin of the pronotum with 2 rows of macrosetae; anterolateral row 6‒7 short setae and, after a gap of the length of a scale, 3 progressively longer plumose setae in the anterolateral corner, close to the first lateral comb ( Fig. 23 ). Pronotum with 5 lateral combs, meso- and metonotum with 6 lateral combs with 1–3 (usually 2) macrosetae. Posterolateral combs with 2‒3 macrosetae. Some macrosetae of the lateral combs longer than half the length of a thoracic segment. Anterior trichobothrial areas of the pronotum and mesonotum situated on lateral comb N-2 (antepenultimate). Anterior trichobothrial areas of the metanotum associated with comb N-1 (penultimate). Posterior trichobothrial areas of the nota associated with the last lateral combs (N).

Prosternum and mesosternum subtriangular, slightly wider than long at their bases ( Fig. 24 ). Metasternum clearly wider than long (ratio length/width of prosternum 0.9, of metasternum about 0.84). All thoracic sternites with relatively acute hind margins ( Figs. 24‒26 ), bearing macrosetae only in their apical part, concentrated on the margins and not clearly arranged in defined combs; 2+2 poorly defined combs visible on the prosternum and mesosternum, composed of 2‒4 macrosetae. Combs of metasternum (also 2+2) with 3‒5 macrosetae and more clearly defined ( Fig. 26 ). Distance between the pair of subapical combs about 3 times the width of a comb.

Protibiae approximately 2.6 times longer than wide; mesotibiae 2.8‒2.9 times longer than wide and 1.25 times longer than the protibiae; metatibiae about 3.75 times longer than wide and 1.75 times longer than the protibiae. Apart from the usual setae, plumose macrosetae on the tibiae as follows: on tibia I, 2‒3 dorsal and 4 ventral, on tibia II, 3 dorsal and 4‒6 ventral, and on tibia III 2 dorsal and 6‒8 ventral ( Fig. 27 ); all macrosetae shorter than the diameter of the article. Scales of femora rounded. Tibiae without scales.

Urotergite I with 1+1 bristle-combs. Urotergites II–VI with 3+3 combs; urotergites VII and VIII with 2+2 combs. Lateral bristle-combs with 3‒6 macrosetae, sublateral combs with 3 macrosetae in urotergites II‒VI and 4‒5 macrosetae in urotergites VII and VIII; submedian combs usually with 2‒3 macrosetae, this comb asymmetrically absent on urotergite II of holotype ( Fig. 28 ). Urotergite X trapezoidal, short, the trapezoidal process about 0.32 times longer than wide at the base, with straight or slightly concave hind border, ( Fig. 29 ) and 1+1 combs of 5 macrosetae each. Urosternite I without setae, urosternites II–VI with small median comb of 3‒4 macrosetae. Urosternites III‒VIII with 1+1 lateral combs of 5‒7 macrosetae.

One pair of abdominal styli. Inner process of coxite IX shorter than wide at its base (ratio length/width about 0.86) and 2.5 times longer than the outer process ( Fig. 30 ). Styli 2.25 times longer than the inner process of the coxite. Caudal filaments broken; maximum length of a cercus 1.3 mm, (of the paracercus 1.5 mm).

Etymology. This new species is named for the Iranian province where it was collected, Kermanshah.

Discussion. This new species, like the previous one, belongs to the “villosa” group of the subgenus Sceletolepisma sensu Irish (1996) . Inside this diverse group, the new species can be compared with those sharing the following characters: urotergites II‒VI with 3+3 combs, 2+2 combs on urotergite VII, absence of a transverse comb on coxite IX, and 3 papillae on the apical segment of the labial palp. Four species share this combination of characteristics: C. canariense Mendes, Molero, Bach & Gaju, 1993 , from the Canary Islands, C. roszkowskii Stach, 1935 from NE Africa and SW Asia, C. halophilum Kaplin, 1981 and C. kuhitangicum Kaplin, 1993 (the two latter from Turkmenistan).

Ctenolepisma kermanshanum n. sp. differs from C. canariense in several characters. C. kermanshanum n. sp. has a mesosternum that is wider than long and has two pairs of combs on the metasternum, and has longer tibiae (length/width ratio 3.75). In C. canariense the mesosternum is longer than wide and has only one pair of combs, and the tibia ratio is 3.25. The holotype of C. canariense has two pairs of styli, while C. kermanshanum n. sp. has just one pair, but this is not a comparable character since the former is a female and the latter are males.

Ctenolepisma halophilum differs from the new Iranian species in lacking posterolateral combs on the nota, which is an unusual character state for Ctenolepisma , suggesting that this Turkmenian species could be placed in another subgenus or genus after a deeper study of characters not considered in traditional descriptions. This revision would need to include comparison with another taxon that shares this character state: Ctenolepisma calvum (Ritter, 1910) , described as Peliolepisma calva and included posteriorly in Ctenolepisma by Paclt (1967).

Ctenolepisma kuhitangicum appears to be closely related to C. kermanshanum n. sp. The number of combs is the same in both species, but the number of setae per comb is generally higher in C. kuhitangicum . As setal presence could correspond with the smaller size of the Iranian specimens, it could be argued that this number might increase in later moults and that C. kuhitangicum and C. kermanshanum n. sp. could be conspecific. However, significant differences exist, for example, in the shape of the apical part of the thoracic sternites. In C. kermanshanum n. sp. the apical parts of the mesosternum and the metasternum are more acute and, apparently, all these sternites are longer than they are wide in the species from Turkmenistan (slightly wider than long in C. kermanshanum n. sp.). The tenth urotergite of C. kuhitangicum has a slightly convex hind margin, while in C. kermanshanum n. sp. it is slightly concave; moreover, the ratio length/width of the trapezoidal process of the tergite is 0.27 in the species from Iran and higher (about 0.34) in C. kuhitangicum , based on illustrations in Kaplin (1993). Following the same method, the ratio length/width of the inner process of coxite IX of the male is about 0.69 in C. kuhitangicum and about 0.86 in C. kermanshanum .

C. roszkowskii , described from Egypt and Libya and later reported from Palestine (Wygodzinsky, 1942), Israel (Wygodzinsky, 1952; Mendes, 1995) and Turkey (Wygodzinsky, 1959) has, in common with C. canariense , only one pair of large combs on the metasternum, but C. kermanshanum n. sp. also has two pairs of small, clearly separated combs. Urotergite X in C. roszkowskii is clearly longer than in C. kermanshanum n. sp., based on the illustrations in Stach (1935). The number of lateral notal combs is greater in C. roszkowskii (7‒9 on meso- and metathorax) than in C. kermanshanum n. sp., (5‒6), and the number of setae in the thoracic and abdominal combs is also greater in C. roszkowskii . The prosternum has 3‒4 pairs of well-defined combs with up to more than 10 macrosetae in C. roszkowskii , but in C. kermanshanum n. sp. there are only 2 pairs of poorly defined combs with no more than 4 or 5 macrosetae. The specimens on which Stach based his original description were larger (length 10 mm) and the specimens of the new species are clearly smaller (5.5 mm).The type specimens of both species bear only one pair of styli, which suggests they could be juveniles, but otherwise they seem to be mature specimens, and the previously mentioned characters are sufficient for separation.

Figures

FIGURES 21 ‒ 26. Ctenolepisma kermanshanum n. sp. Holotype. 21. Maxillary palp. 22. Labial palp, apical article with detail of the basiconic sensilla of the outer part of the article. 23. Anterolateral corner of the pronotum. 24. Prosternum. 25. Apical part of the mesosternum. 26. Metasternum. Scales: 0.1 mm.

FIGURES 27 ‒ 30. Ctenolepisma kermanshanum n. sp. Holotype. 27. Hind tibia showing the arrangement of macrosetae. 28. Urotergite II with asymmetric setation. 29. Urotergite X. 30. Coxite IX and stylus. Scales: 0.1 mm.