Oncopodura moghanensis Mehrafrooz Mayvan & Kováč, 2024

Mehrafrooz Mayvan, Mahmood, Parimuchová, Andrea & Kováč, Ľubomír, 2024, A new subterranean species of Oncopodura Carl & Lebedinsky, 1905 (Collembola, Entomobryomorpha, Oncopoduridae) from a cave in Northeastern Iran, Subterranean Biology 49, pp. 31-51 : 31-51

Oncopodura moghanensis Mehrafrooz Mayvan & Kováč sp. nov.

Figs 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , Table 1

Diagnosis.

PAO with 6 long, subequal lobes, each lobe secondarily divided into 3–6 fingers. Unguis normal, not elongated, untoothed; unguiculus acuminate. Dorsal side of manubrium with 11 + 11 setae. Dens at basal part with 1 dorsoexternal and 2 dorsointernal hooks, at the distal part with 1 dorsoexternal and 3 dorsointernal hooks. Mucro with 4 teeth.

Type locality.

Iran, Razavi Khorasan province, Mashhad city, Moghan village, Moghan Cave, Coordinates: 36 ° 06 ' 59 " N, 59 ° 22 ' 06 " E, 2193 m a. s. l.

Type material.

Holotype: female on slide [ MoCa 101 ], dark zone, the end part of the cave, 2 nd cave floor, collected from water pond surface, 28. ix. 2022, temperature = 11.9 ° C, RH 73.0 %, leg. M. Mehrafrooz. Paratypes: 4 specimens on slides [ MoCa 102 , MoCa 103 , MoCa 104 , MoCa 105 ] , ibidem, hand collecting on a stalagmite, 30. iv. 2022, temperature = 12.0 ° C, RH 73.4 %, leg. M. Mehrafrooz . Holotype and one paratype deposited in UPJŠ; three paratypes deposited in ZMFUM.

Description.

Body appearance. Length 1.05 mm on average (n = 5, max. length 1.2 mm). Colour white without traces of pigment, body covered by hyaline scales.

Antenna. Antenna nearly as long as head, without apical bulb and scales (Fig. 4 A – E ). length of Ant I: II: III: IV as 0.02: 0.04: 0.06: 0.08 mm respectively. Ant I with 7 thick dorsal setae and 11 normal setae (smaller than those of Ant II – III). Ant II with 1 broad wrinkled apical sensillum similar to those of Ant III, 1 apical blunt sensillum, 11 dorsal and 6 ventral setae and 4 dorsolateral microsetae. Ant III with sensory organ formed by 2 expanded wrinkled sensilla with 1 blunt, basal sensillum, 8 thick setae at their base, and 10 slender, long setae covered by very soft cilia (Fig. 4 B ). Ant IV not elongated, with a row of 4 thick and pointed sensilla (Fig. 4 C – E ), equally distant from each other, and 2 subapical modified setae (Fig. 4 D ). Ventral side of Ant IV with normal setae, dorsal part with normal and elongated setae.

Head. Eyes absent. PAO well developed and located near base of Ant I, very distinct and large, about 24 µm in diameter, with 6 subequal lobes formed around a central circle, each lobe secondarily divided into 3–6 irregular finger-like lobes (Fig. 5 A ). Labrum with 4 prelabral setae and 4 rows of 2, 3, 5, 4 setae on papillae (Fig. 6 A ). Left mandible with 4 teeth and right mandible with 3 teeth.

Ventral head without scales, chaetotaxy (setal pattern) as in Fig. 5 C , all ventral setae smooth. Head dorsally with 4 + 4 inter-antennal and 5 lateral macrosetae on each side placed around PAO; 1 short and thick seta posterior to PAO. Two rows of 5 and 6 macrosetae, respectively, in front of prelabral setae. Head with scales, dorsal microsetae as in Fig. 6 B . Labial triangle with 7 smooth macrosetae (Fig. 5 B ).

Body chaetotaxy. As in Fig. 7 A, B . The chaetotaxy follows the general pattern described for the genus ( Szeptycki 1977; Jordana et al. 2012). Mesothorax extended forward slightly over the head, distally with a row of smooth spine-like setae, laterally with 1 ciliated spine-like seta and 1 trichobothrium and 1 + 1 medial pseudopores. Metathorax with 2 + 2 trichobothria, 2 + 2 lateral spine-like setae and 1 + 1 medial pseudopores. Abdomen I with 1 + 1 ciliated spine-like setae and 1 + 1 medial pseudopores, Abd. II with 1 + 1 lateral smooth spine-like microsetae, medially with 1 + 1 ciliated spine-like setae, 1 + 1 trichobothria and 1 + 1 medial pseudopores, Abd. III laterally with 1 + 1 smooth spine-like microsetae, medially with 1 + 1 ciliated spine-like setae and 1 + 1 pseudopores. Abd IV with 4 + 4 ciliated macrosetae and 1 + 1 pseudopores. Abd V with 2 + 2 anterior sensilla, 5 + 5 ciliated macrosetae (shorter than Abd IV macrosetae) and 1 + 1 smooth spine-like microsetae. Abd VI: epiproct with 9 + 9 ciliated and 1 + 1 smooth setae, paraproct with 12 ciliated macrosetae and 8 smooth setae.

Legs. Legs without scales. Chaetotaxy as in Fig. 8 A – C . Leg I: trochanter with 6 setae, femur with 3 whorls of 4, 4, 4 setae, respectively; whorl 2 with 1 microseta and whorl 4 with 2 microsetae; Ti with 5 whorls of 4, 4, 5, 4, 7 setae, respectively. Leg II: trochanter with 5 setae, femur with 3 whorls of 4, 3, 5 setae, respectively; whorl 3 with 2 microsetae; Ti with 5 whorls of 4, 4, 4, 4 and 6 setae, whorl 2 with 1 stout, clavate (apically expanded) macroseta. Leg III: trochanter with 4 setae, femur with 3 whorls of 3, 3, 5 setae; Ti with 5 whorls of 4, 4, 4, 5, 6 setae respectively, whorl 5 with 1 microseta. Most Ti setae large, acuminate, and extremely finely ciliated; tenent hair slender and acuminate. Unguis (Fig. 9 A – C ) normal, not elongated, untoothed; inner pretarsal setae long, slightly shorter than the unguiculus, about 1 / 2 length of internal side of unguis; outer pretarsal setae shorter; unguiculus acuminate.

Ventral tube (collophore) without prominent papillae, with 3 + 3 setae (2 + 2 dorsolateral and 1 + 1 frontal). Tenaculum with 4 + 4 teeth, setae absent.

Furca. length of manubrium: dens: mucro as 0.046: 0.040: 0.031 mm respectively. Ventral side of manubrium with scales, dorsal side with 3 + 3 long and 1 + 1 short smooth setae, 6 + 6 ciliated axial macrosetae; 1 + 1 long, feather-like distal macrosetae reaching half of the dens (Fig. 10 A ). Ventral side of dens with scales; chaetotaxy of dorsal side of dens subdivided into basal and distal part. Basal part with 2 dorsointernal ciliated hooks, 1 dorsointernal smooth conical spine (broad at the base and strongly tapered at the top), 1 dorsoexternal ciliated hook and 5 dorsal ciliated macrosetae (basal tubercle with 2 ciliated macrosetae, of which inner 1 feather-like and thinner than outer one). Distal part of dens with 3 dorsointernal ciliated hooks (1 medial, 2 distal), 1 dorsoexternal ciliated hook, 2 dorsal ciliated macrosetae and 2 dorsal short, smooth medial spine-like setae. Dens apically with 5 smooth ventral setae (Fig. 11 A, B ). Mucro with 4 teeth: 2 apical, 1 medial and 1 basal; 2 scales at its basal half (Fig. 10 B ).

Etymology.

The name of the new species is derived from the Moghan Cave in Kopet Dag Mountains in northeastern Iran, i. e. the locality where the species was discovered.

Taxonomic remarks.

So far, 50 species of Oncopodura have been described. Based on shape of PAO, Oncopodura moghanensis sp. nov. is similar to O. dethieri Janssens & De Bruyn, 2010 , O. egerszogensis Loksa, 1961 and O. reyersdorfensis Stach, 1936 . The new species is characteristic with 3–6 finger-like lobes in PAO vesicles, while O. dethieri has 2–3 fingers, O. egerszogensis has 3 fingers and O. reyersdorfensis has 1–2 fingers in PAO. Based on dorsal chaetotaxy of dens, O. moghanensis sp. nov. is similar to O. crassicornis Shoebotham, 1911 , O. pelissiei Deharveng, 1988 and O. itatiaiensis Arlé, 1961 . However, Szeptycki (1977) mentioned more complex chaetotaxy of manubrium for O. crassicornis , when comparing it with O. yosiiana Szeptycki, 1977 . The new species has 6 long and subequal lobes in PAO with each lobe secondarily divided into 3–6 fingers, while O. crassicornis and O. pelissiei has 6 simple lobes and O. itatiaiensis 5 simple lobes in PAO. Among other species, O. yosiiana differs from the new species by 6 simple lobes in PAO, manubrium with numerous dorsal setae (16 + 16 feather-like setae, 6 + 6 smooth mesosetae, 1 + 1 smooth microsetae and 1 + 1 ciliated macrosetae), and dens without basal external hook.

Deharveng (1988) recognized two basic groups of Oncopodura congeners:

O. crassicornis – group: Ant IV with 4 short and thick sensilla (S-setae) arranged in a curved line, thickened sensilla at the base of segment absent; PAO large with 6 elongated lobes; unguis without large basal lamella (external tooth); pretarsal setae long; dental hooks finely scaly-ciliated, lacking strong denticles.

O. tricuspidata – group: Ant IV with 4 thick sensilla (S-setae) arranged in a line, and one thickened sensillum at the base of segment (sometimes absent); PAO small, with 3–4 rounded lobes, or they are absent; unguis with large basal lamella, dental hooks smooth, but with strong denticles on their outer surface.

Recently, numerous species have been described with various combinations of the group-specific characters. In many species of O. crassicornis – group, Ant IV sensilla are in a line and in some species Ant IV basal sensilla is present, such as in O. ambigua Christiansen, 1957 and O. hubbardi Christiansen & Bellinger, 1996 . Also, PAO in O. hubbardi , O. itatiaiensis and O. tunica Christiansen & Bellinger, 1980 have 5 lobes and in O. pegyi Gruia, 1994 has 6–8 lobes. Unguis basal lamella is present in species including O. ambigua , O. hubbardi , O. itatiaiensis and O. tunica .

In some species of O. tricuspidata – group, ant IV basal sensilla is absent such as O. cruciata Bonet, 1943 , O. equatoriana Thibaud & Najt, 1987 , O. hoffi Christiansen & Bellinger, 1980 , O. iowae Christiansen, 1961 , O. mala Christiansen & Bellinger, 1996 , O. meridionalis Cassagnau, 1959 , O. puncteola Yosii, 1956 and O. subhoffi Christiansen & Bellinger, 1998 . Also, there are some species with 1 single lobe PAO including O. cavernarum Stach, 1934 , O. gledensis Baquero et al., 2007 , O. mala , O. siquierae Seminario-Cordova et al. 2018 and O. vioreli Gruia, 1989 . On the other, ungual basal lamella is absent in some species including O. cruciata , O. equatoriana , O. hoffi , O. iowae , O. mala , O. meridionalis , O. puncteola and O. subhoffi . Thus, practical use of sorting of Oncopodura congeners to tricuspidata - and crassicornis - group has become questionable.

The new species was collected in the deep cave zone but, nevertheless, it does not show morphological adaptations to subterranean environment such as elongation of unguis or increase in the number of sensilla on antennae and body or augmentation of setae over the head, characteristic for some troglomorphic congeners (e. g. Deharveng 1988).

Figures

Figure 1. A Razavi Khorasan province in Iran is marked with an orange color; location of the Moghan Cave, where the new Oncopodura species was collected, is marked with an asterisk B cave entrance and surroundings of Moghan Cave in autumn (Photo: M. Mehrafrooz).

Figure 2. Moghan Cave, northeast Iran A main entrance of the cave in spring (Photo: M. Mehrafrooz) B second entrance (Photo: M. Mehrafrooz) C two cave entrances, view from inside the cave (Photo: M. Mehrafrooz) D pool at the end of the cave located on the second floor (Photo: Vahid Ashrafi).

Figure 3. Ground plan of the Moghan Cave (Sketched by V. Ashrafi).

Figure 4. Oncopodura moghanensis sp. nov. A antennal segments I – III B detail of finely ciliated seta C antennal segment IV D detail of two subapical modified setae near the apical sensillum E detail of thick, pointed sensillum. Scale bars: 0.02 mm.

Figure 5. Oncopodura moghanensis sp. nov. A postantennal organ B labium and labial triangle C ventral head chaetotaxy. Scale bars: 0.01 mm (A, B); 0.02 mm (C).

Figure 6. Oncopodura moghanensis sp. nov. A labrum B dorsal head chaetotaxy (dotted circle = inter-antennal macrosetae). Scale bars: 0.01 mm (A); 0.02 mm (B).

Figure 7. Oncopodura moghanensis sp. nov. A dorsal chaetotaxy of thorax and abdomen B abd V & VI (S = anterior sensilla; circles with a slash represent pseudopores). Scale bars: 0.096 mm (A), 0.01 mm (B)

Figure 8. Oncopodura moghanensis sp. nov., chaetotaxy of legs A leg I B leg II C leg III. Scale bars: 0.02 mm.

Figure 9. Oncopodura moghanensis sp. nov., detail of foot complex A leg I B leg II C leg III. Scale bar: 0.01 mm.

Figure 10. Oncopodura moghanensis sp. nov. A manubrium dorsal side B mucro with basal scale. Scale bars: 0.01 mm.

Figure 11. Oncopodura moghanensis sp. nov., dorsal side of dens A dens with dorsolateral hooks and spines B dens with ciliated dorsal macrosetae. Scale bars: 0.01 mm.