Hymenaphorura kalindera, Weiner & Fiera, 2020

Weiner, Wanda Maria & Fiera, Cristina, 2020, Two new species of Hymenaphorura Bagnall, 1948 (Collembola, Onychiuridae) from Romania and an updated key to the genus, ZooKeys 960, pp. 17-38 : 17

Hymenaphorura kalindera sp. nov. Figures 1A-H , 2A-H , Table 1

Material examined.

Holotype: female (IBB: RO-Hym1-IBB): Romania, Prahova County, Bucegi Massif, Buşteni near Kalinderu ski slope, 45.4212N, 25.52458E, 1000 m a.s.l., fir and beech forest, litter sample, 14.XI.2017, coll. C. Fiera. Paratypes: female stored in Poland (ISEA: RO-17-1) and juvenile in Romania (IBB: RO-Hym2-IBB) same data as holotype.

Diagnosis.

Body with distinct areas of coarser granules. Dorsal pso formula as 10/011/11112, ventral pso absent. PAO with 9-12 simple vesicles, parallel or oblique in relation to the long axis of this organ and one border seta. Abd. terga I-III with setae p2 and p3 subequal. Abd. tergum V granular area with 4+4 distinct macrosetae. Distal tibiotarsal whorl with 11 setae.

Description.

Measurements (in mm). Holotype female length 0.81, paratype female: 0.78, paratype juvenile 0.71.

Body. Body elongate, cylindrical (Fig. 1C ). Colour in alcohol white. Distinctive areas of granulation on dorsal side of the body of c2 type (sensu Arbea and Jordana 1994). Usually 12-13 grains around each pseudocellus (Fig. 1B ).

Antennae and head. Antennae almost as long as head. Antennal segment I with 8 setae, antennal segment II with 15 setae. AIIIO consisting of four guard setae, five papillae, two smooth sensory rods, two granulated sense clubs: granulated and bent (Fig. 1A ), ventro-lateral microsensillum present. Second external papilla in AIIIO forked in holotype, simple in two other specimens. Antennal segment IV with one distinct sensillum, small subapical organite in deep, narrow pit and latero-external microsensillum in the last posterior row of setae (Fig. 1A ).

PAO with 8-12 beanlike vesicles, parallel or oblique in relation to the long axis of this organ in: holotype 10/12, paratypes 8/11 and 10/10 simple; PAO groove border with 1 seta (Fig. 1B ). Labral formula of setae: 4/3,2,2. Maxillary palp simple with two sublobal sensory hairs. Labial type A (sensu Fjellberg 1999) with four papillae, papilla E absent (Fig. 1E ). Guards a1, b1-2 and d2 (not well visible) as long as half of terminal sensilla of papillae. Five other guards as long as terminal sensilla.

Pseudocellar formula. Pseudocellar formula per half tergum dorsally: 10/011/11112 (Fig. 1C ), ventrally and on subcoxae 1 absent. Parapseudocelli and pseudopores not visible.

Dorsal chaetotaxy. Dorsal chaetotaxy as in Figs 1C , 2A-H always with some asymmetry. Seta d0 on the head absent. Body with macro-and meso/microsetae, sensory setae s well distinguished on head, abdominal terga I, IV and V, their formula per half tergum: 2/000/10012.

Thoracic terga II and III with strong lateral microsensilla (ms). Thoracic tergum I with 7(6)+7(6) setae. Thoracic terga II and III with 5+5 macrosetae and 4+4 microsetae along midline. Abdominal terga I-III with 5+5 macrosetae and 3+3 microsetae along midline. Setae p2 and p3 on abdominal terga I-III subequal. Granulated area of abdominal terga I-III with 4+4 setae, in row p of abdominal tergum V with 4+4 macrosetae as p2, p5, m4, a4. One macroseta in the set of setae on subcoxae 1 and abdominal pleura I-IV and 2 macrosetae on abdominal pleurum V. Abdominal tergum V with medial seta p0 (absent in juvenile), VI with medial setae a0 and p0. Anal spines as long as inner edge of claw III and 2.5 times as long as their basal diameter. Basal papillae low.

Ventral chaetotaxy, furcal rudiment. Thoracic sterna II and III with 1 + 1 setae. Ventral tube with 7-9+7-9 setae. Male unknown. Abdominal pleurae II-V with 1, 2, 2, 2 macrosetae respectively. Abdominal sternum IV (Fig. 1F ) with furcal rudiment as small finely granulated area and with two manubrial rows of setae: row ma with two setulae and row mp (irregular) with two macrosetae and 3-4 microsetae between them. Anal valves with numerous acuminate setae; each of lateral valves with three setae in a-row (a1-a0-a1) and five setae in b-row (b2-b1-b0-b1-b2), upper valve with one seta in a-row (a0), with four setae in b-row (b2-b1-b1-b2) and with three subequal setae in row c (c2-c0-c2) (Fig. 1H ).

Legs. Chaetotaxy of legs I, II and III as follows: subcoxae 1 with 4, 4, 4 setae, subcoxae 2 with 1, 4, 4 setae, coxae with 3, 9-10, 12 setae, trochanters with 8, 8, 9 setae, femora with 16, 14, and 14 setae, tibiotarsi with 3 whorls of setae: 20 (1,8,11), 20 (1,8,11), 19 (1,7,11) setae respectively (Fig. 1D ). Seta M present. Claw without internal denticle. Empodial appendage with short basal lamella, length of empodium is about 2/3 of inner edge of claw III (Fig. 1D ).

Ecology.

This species is found in litter samples in mixed fir and beech forest.

Etymology.

The name of the new species is inspired by the name of the ski slope: Kalinderu, Bușteni town, Prahova county, Romania.

Remarks.

Hymenaphorura kalindera sp. nov. belongs to the group of species with 4+4 macrosetae on the granulated area of the abdominal tergum V (Table 1 ). Hymenaphorura maoerensis Sun, 2014, H. rafalskii Weiner & Szeptycki, 1997, and H. wusuliensis Sun & Wu, 2011 are different from this and other species by two border setae on the PAO. Hymenaphorura rafalskii and wusuliensis have 2+2 anterior pso on the head and 3+3 pso on the Abd. tergum V.

The other species: H. anatolii Pomorski 2001 (Russia, northern Palearctic), H. gamae Arbea & Jordana, 1994 (Spain), H. ioni Busmachiu, Popa & Weiner, 2014 (Romania), H. palaearctica Pomorski, 2001 (Russia), and H. subsimilis Bagnall, 1948 (Romania) form a group of more similar species with 11 setae in the tibiotarsal distal whorl, with the pso formula 10/011/11112, and with one setae on the border of the PAO. The new species differs from these species by the number of s-setae on Abd. V (2+2 vs 1+1), by the presence of four setae on each of the granulated areas of Abd. I-III and by its smaller size (Table 1 ). A comparison with H. subsimilis , a species described from the same county (Prahova), is rather difficult because only one type specimen is not in good condition (see Remarks for H. subsimilis ). These species differ in their size: H. subsimilis is larger than H. kalindera sp. nov. (1.01 mm vs 0.81 mm), and H. subsimilis has Th. I with 4+4 setae (juvenile specimens?) in one row vs 7+7 or 6+7 setae in two rows in the new species. Abd. V has 1+1 s-setae in H. subsimilis vs with 2+2 s-setae in the new species. The shape of vesicles in PAO are transversally lobed in H. subsimilis vs bean-like in shape in the new species. The upper anal valve setae in c-row are equal in the new species and, in H. subsimilis , seta c0 is longer than setae c2.

Figures

Figure 1. Hymenaphorura kalindera sp. nov. A antennal segment III and IV B postantennal sensory organ and anterior cephalic pseudocellus C habitus and dorsal chaetotaxy D leg III: tibiotarsal chaetotaxy and claw E labial palp F abdominal sternum IV with furcal rudiment G abdominal terga V and VI H abdominal sternum VI: anal valves. Scale bars: 0.05 mm (A, B, F-H); 0.01 mm (B, E); 0.1 mm (C).

Figure 2. Hymenaphorura kalindera sp. nov.: dorsal chaetotaxy. A head B thoracic tergum I C thoracic tergum II D abdominal tergum II E abdominal tergum III F abdominal tergum IV G abdominal tergum V H abdominal tergum VI.