Lepidospora (Brinckina) momtaziana Molero, Tahami, Sadeghi & Gaju

Molero, Rafael, Tahami, Mohadeseh Sadat, Gaju, Miquel & Sadeghi, Saber, 2018, A survey of basal insects (Microcoryphia and Zygentoma) from subterranean environments of Iran, with description of three new species, ZooKeys 806, pp. 17-46 : 17

Lepidospora (Brinckina) momtaziana Molero, Tahami, Sadeghi & Gaju sp. n. Figs 9, 10, 11, 12, 13, 14, Table 3

Type material.

Holotype (MNCN): male, body length = 7 mm, mounted on slide, labelled "Momtaz cave, Marvdahst, Fars Province, Iran. 11-XI-2016, Cat. Types N. 2836"; "HOLOTYPE ♂ Lepidospora (Brinckina) momtaziana sp. n., des. Molero, Tahami, Sadeghi & Gaju, 2018". Paratypes (2 ex.): One female, collected in the same locality and date (preserved in alcohol and deposited in ZM-CBSU #C2638). One female from the same locality, 18-II-2015, mounted in slide and reported as Lepidospora (Brinckina) sp. in Tahami et al. (2018), deposited in UCO (Ref. Z2513).

Diagnosis.

Light yellowish nicoletiid; adults about 7 mm long, antennae slightly longer. Body covered with scales except on head (typical in the subgenus Brinckina ). Pedicel of male antennae with slightly asymmetrical apophyses; this asymmetry involves shape and chaetotaxy. Dorsally with few setae, those inserted on the disc of nota very small and sparse, their length about 1/20 of the respective notum. Male urotergite X with 7+7 pegs, 3+3 of them inserted on the posterolateral projections. Subgenital plate of female widely triangular. Male cerci with 6 pegs arranged in a single row, the basal division with 1-2 pegs.

Description

. Body length of the male (holotype): 6.8 mm. Length of the female (paratype): 7.7 mm.

Thorax length: 2.5-2.6 mm. Thorax width: 1.4-1.7 mm. Shape of the body subcylindrical, the thorax nearly as wide as the abdomen. Epidermal pigment light yellowish, slightly darkened in the abdomen; gut contents are visible because transparency of the teguments. Head completely devoid of scales, thorax and abdomen covered dorsally and ventrally by scales. Scales as in Figure 9A, a little longer than wide, thoracic scales about 40-50 µm long, with 6-8 rays which extend slightly beyond the margin, abdominal scales slightly larger, with 8-15 rays.

Head prognathous, with some bifid macrosetae inserted in the lateral margins of the cephalic capsule, frons and in the middle of clypeus and labrum. Some dispersed setae are irregularly arranged in the cephalic capsule (Fig. 9B).

Antennae slightly longer than body; in the holotype they are 7.6 mm long. Scape 1.5 times longer than wide and almost twice longer than pedicel (3 times longer in the female), with 3 bifid macrosetae inserted on its apical half, and some additional thin setae of variable length (Fig. 9C). Pedicels of the male with apophyses that appear to be asymmetric. They are subcylindrical but the left apophysis is broader basally and narrower in its apical half (ratio length/width at the base: 1.6), with a blunt apex and the right apophysis is slightly longer (ratio length/width at the base: 2.4), without abrupt narrowing in its distal half and apically more acute. Both apophyses are similar in length (their distal end reaches the level of the third annuli); so it can be thought that this different shape could be explained by a different angle of vision because their different position in the slide, but the chaetotaxy of both apophyses does not match; the left apophysis has two insertions of setae nearly at the same level in its apical part and the right apophysis shows two acute setae in the apical part but they are inserted in different positions. Both apophyses have a glandular seta inserted subapically and the right apophysis has a more prolonged apex beyond the insertion of the seta. In the basal part of the apophyses, there is a fovea with several small setae. Three additional long macrosetae are inserted in the distal part of the trunk of the pedicel, just under the limit with the flagellum (compare Figs 9D and 10A with Figs 9E and 10B). Pedicel of the female without apophysis and with five long macrosetae. Basiconic sensilla long, abundant on the flagellum, especially in T-joints, i.e., those annuli bearing trichobothria. Mandibles and maxillae without distinctive features. Last article of maxillary palps only preserved in the holotype, with several (usually 5) apical sensory rods and a subcircular sensilla apically. The three distal articles of these palps (last, penultimate and antepenultimate) with scattered long basiconic sensillae. Apical article of the maxillary palp about 6.8 times longer than wide and 1.15 times longer than the penultimate (Fig. 11A); this latter of similar length than the antepenultimate. Galea with two apical conules (Fig. 11B). Apical article of the labial palp about 1.5-1.7 times longer than wide and 1.5-1.6 times longer than the penultimate, with 6 sensory papillae arranged as usual in the genus (Fig. 11C). Inner side of this article with 5-6 thin-walled basiconic sensilla; outer side with 4-5 similar sensilla, most slightly curved basally and inserted in the basal half of the article.

Most thoracic and abdominal macrosetae are lost in both available specimens and only their insertions are visible; when preserved, their length is about 1/4 - 1/5 of the length of the respective tergite. Nota (Figs 11D, 12A, B) with several bifid macrosetae of variable length irregularly inserted on their lateral and posterior borders; the pronotum also bears these setae (10-14) on its anterior margin, although most of them are lost and only their insertions are visible (Fig. 11D). Moreover, there are a lot of small simple setae over the lateral margins of the nota and in the anterior margin of the pronotum and the posterior margin of the metanotum (Fig. 12B). These thin and short setae (considered as microchaetae) are very scarce in the disc of the nota but there is a significantly higher number in the anterior part of the pronotum of the holotype (Fig. 11D).

Protibiae about 4.2-4.4 times longer than wide, with 2 dorsal and 4-5 ventral spines (apart from a row of 5-7 short spines in the ventro-apical angle of the tibiae (Fig. 12C). Mesotibiae about 4.5-4.75 times longer than wide, with the same number of distribution of spines than protibiae. Metatibiae about 5.3-5.4 times longer than wide (Fig. 12D) and 1.75 times longer than protibiae, with 1 small dorsal spine (which can be absent) and 4 ventral, two of them inserted very apically on the article. Ventral spines shorter than or as long as the diameter of the tibiae. Tibiae about 1.5-1.6 times longer than the first article of the metatarsi. Metatarsi about 1.3-4.0 times longer than tibiae. Praetarsi with 3 simple claws, the median one shorter than the lateral ones.

Urotergites covered by scales; dorsal and ventral scales similar. Dorsal scales make difficult to discern a faint suture between the tergite and the paratergite. Some abdominal tergites are damaged in the holotype and the urotergal chaetotaxy is more visible in the paratype. First urotergite (Fig. 12E) with several small setae inserted in the disc, the remaining urotergites with very few, or completely devoid of, discal setae. The posterior margin of urotergites with 4-5 + 4-5 isolated bifid macrosetae (most of them lost and only their insertions are visible) and with some thin and short acute setae, those of the infralateral region longer (Fig. 13A).

Urotergite X of the male (Fig. 13C) with concave and rounded hind margin and two posterolateral projections which are curved downwards. The posterior part of the tergite bears ventrally 7+7 pegs (on each side, 3 inserted in the posterolateral projection and 4 near the lateral margin of the tergite; on the left side the anterior peg is smaller and thinner than the others, tending to a spiniform shape). Disc of the tergite nearly devoid of setae, only some insertions are visible near the posterior notch and in lateral margins. There are some small and thin setae in these margins, one of them near the apex of the posterolateral projections.

Urotergite X of the female without pegs, its hind margin with a shallow concavity and 1+1 macrosetae inserted in the posterolateral angles (Fig. 13B); the disc, as in the male, nearly without setae.

Urosternite I broken in both available specimens, but the sutures delimiting laterocoxites are visible in the holotype, as well as the setation of the hind margin, consisting in few small setae in the median region and some others in the lateral part (Fig. 13D). Eight pairs of styli, inserted on urosternites II-IX. Eversible vesicles present in urosternites II-VI and pseudovesicles in the urosternite VII. Setation of urosternites II-VII as in Fig. 13E, with 1+1 discal macrosetae, some small setae on the disc, and the hind margin with 1+1 submedian macrosetae (between both vesicles), 1+1 sublateral macrosetae (inserted between vesicles and the basis of the styli) and several acute setae in the outer part, more lateral than styli.

Urosternite VIII of the male entire, of females divided in free coxites. Subgenital plate of the female triangular, with acute hind margin, wider than long (ratio length/width about 0.75), with 1+1 short discal macrosetae (bifid) and several setae on the lateral margins (Fig. 13F).

The genital region of both specimens is damaged, so in the male the hind margin of the urosternite VIII is not visible and the penis and the paramera are lost, and the ovipositor of the female is broken basally, so the length, number of divisions (only 5 are preserved) and the characteristics of the apices of gonapophyses are not known. Terminal filaments probably long but broken basally in the available specimens; maximum preserved length is 0.5 mm. Cerci with 5 acute pegs, longer and thinner than those on the urotergite X (Fig. 14A, B), 1-2 on the proximal division, 3 on the second division and 0-1 on the third division, arranged in a single row. The short basal part of the paracercus that is preserved shows one spiniform small peg in the apical limit of the basal division, the second division is lost (Fig. 14C).

Discussion.

This new species of Lepidospora can be assigned to the subgenus Brinckina Wygodzinsky, 1955 because the absence of scales on the head, so it is compared with the previously described species of this subgenus. Unfortunately, some characters considered important in the taxonomy of Nicoletiidae cannot be used for this comparison because of the damaged state of the abdominal regions of the two available specimens. In spite of this, the characters described above are enough to state that Lepidospora (Brinckina) momtaziana sp. n. differs from all previously known species of the subgenus Brinckina . We present a comparison with seven well distinguished and taxonomically non-problematic species, since the status of L. (B.) “meridionalis” var. Silvestri, 1913 and L. (B.) hemitricha var. progressa Silvestri, 1942 remains doubtful and requires further studies, as Mendes (2002) discussed.

With the previously mentioned limitations, three characters have been considered significant to distinguishing between the new Iranian species and the remaining taxa of the subgenus: the shape and length/width ratio of the pedicellar apophyses of males, the setation of the disc of the nota and the number and arrangement of pegs in terminal filaments (mainly in cerci). The comparison based on these characters is summarized in Table 3. More details about the comparison with each of the species are given below.

It worth mentioning that the shape and length/width ratio of the pedicellar apophysis, a distinctive character that can be used only in adult male specimens, should be described carefully. As Molero et al. (2013) stated, "similar antennae placed in different positions could be interpreted as different shapes, but upon rotating the antennae, similar structures can be recognized". Antennae that are presumably considered as symmetrical show different appearances when illustrated in different positions; for example, see the drawings of Smith and McRae (2016) of the left and right pedicellar apophyses of two male specimens of the same species: are they different because an intraspecific variability or because of being drawn in different positions? If we consider the form that can be interpreted from the drawings of the left apophysis, the length/width ratio is about 2.3, but this parameter is approximately 3 in the drawing of the right apophysis. They are similar in length at the same scale; our experience suggests that both apophyses are identical, but the shape of the transversal section of the apophysis is not circular but elliptical; if the left apophysis seems to be wider it is because it is drawn in a different position (seen from the wider diameter of the ellipse) than the right (seen from the narrower diameter). In the new species from Iran, differences between both pedicellar apophyses are not completely explained by different positions (in the slide), so we conclude that they are actually asymmetrical; the difference is not based only in the length/width ratio but also on the shape of the apical part (narrower than the basal in the left apophysis) and on the different chaetotaxy (being aware of the fact that insertions of detached setae must be accounted for).

The following comparisons of other previously described species are based on illustrations from their original descriptions.

Lepidospora (B.) makapaan Wygodzinsky, 1955 from South Africa (Transvaal) has a lot of pegs on the paracercus but lacks pegs on cerci, a character not shared with any other species of the subgenus, including the new species. Moreover, the chaetotaxy of the head and urosternite I is denser in the South African species and the subgenital plate of females is more rounded apically. Adult specimens of L. (B.) makapaan are clearly bigger than adults of the Iranian species, since females of the South African species can reach 16 mm length and their tibia are more than 7 times longer than wide (less than 6 in the new species).

Lepidospora (B.) relicta Smith & McRae, 2016 from northwestern Australia is probably the representative of the subgenus that shows more affinities with the new species from Iran. It is similar because it has pegs on cerci and paracercus and sparse setulae on discs of nota, but males show symmetrical and longer pedicellar apophyses. The number of pegs of the urotergite X is higher (20 against 14 in the new species) and the paracercus (=appendix dorsalis) has 2+2 pegs in the two basal divisions (the Iranian species has only one spiniform seta that can be considered as a peg since it is modified in respect to the remaining setae of the appendix, but nothing can be said about the second division because it is lost).

Males of L. (B.) hamata Mendes, 2002 from Congo has a shorter pedicellar apophysis, which is near to the length/width ratio of L. (B.) momtaziana sp. n., but the shape is different and apophyses seem to be symmetrical; the glandular seta is almost apical in the African species and more subapical in L. (B.) momtaziana sp. n. Moreover, the urotergite X of the male is quite distinct and the species from Congo lacks pegs in the paracercus and the new species shows, at least, one spiniform peg.

Lepidospora (B.) garambensis Mendes, 2002, described from Congo too, is also devoid of pegs in the paracercus and the apophysis of males is longer. Moreover, mesotibiae of L. (B.) garambensis have short strong ventral spines which are absent in the new species.

Males of L. (B.) alticola Wygodzinsky, 1965 (from Kenya) are not known. Comparing females of this species with the new one, the labial palp of this African species is stouter, as long as wide (at least 1.5 times longer than wide in L. (B.) momtaziana sp. n.) and the discal setae of nota are more abundant and longer (about 1/8 of the total length of the nota in the African species and 1/20 in the Iranian species).

Lepidospora (B.) hemitricha Silvestri, 1942 and L. (B.) hemitrichoides Wygodzinsky, 1962 (from China and Afghanistan, respectively) are similar in bearing pegs on cerci and paracercus, and their apophysis have a similar length/width ratio (approximately 2), but the setation of the disc of their nota is stronger (high number of setae and most setae are longer). Additionally, their urotergites X have a higher number of pegs (12+12 in L. hemitricha and about 17+17 in L. hemitrichoides ) and the pegs on cerci are more spiniform (long and acute) in shape. In L. hemitricha , the length/width ratio of their tibiae is lower (about 4 in metatibiae) than in the new species from Iran and males of L. hemitrichoides have longer (finger-like) posterolateral angles of the urotergite X, surrounding a deeper median notch, and the number and distribution of spiniform pegs in the basal division of the paracercus is clearly different from the new species (a lot of pegs in three rows in the Afghan species).

Considering the limitations derived from the lack of information about males of L. alticola and the doubtful status of some species (see above), Lepidospora momtaziana sp. n. can enter in the key of Lepidospora made by Mendes (2002) in at step 34 with the following modifications:

Distribution.

Known only from the type locality, Momtaz Cave, in Fars province, Iran.

Etymology.

The specific name refers to the cave where specimens have been collected. Momtaziana refers to Momtaz, in genitive case, with a feminine ending (-iana) that means "belonging to".

Habitat.

This new species has been collected in the hypogean zone (complete darkness) of Momtaz Cave.