Lepidocyrtus semicoloratus Mateos, 2022

Mateos, Eduardo & Álvarez-Presas, Marta, 2022, Integrative taxonomy reveals three new species of European Lepidocyrtus lignorum-group (Collembola, Entomobryidae), Zootaxa 5100 (4), pp. 451-481 : 472-479

Lepidocyrtus semicoloratus Mateos sp. nov.

Figs 41–56 , Tabs 1–2

Zoobank: urn:lsid:zoobank.org:act:4C8EF42F-8A89-4A7E-AAE5-5B23D310C405

Type material. Holotype: Female on one slide (CRBA-90748), Montseny Natural Park , Aiguafreda, Barcelona ( Spain), 917 m above sea level, lat/long coordinates N41.7892 E2.3113, on herbaceous vegetation, 10.ii.2007, leg. E. Mateos. Paratypes: 6 specimens (1 male, 2 female, and 3 without visible sexual plate) on slides and 18 specimens preserved in absolute alcohol, same data as holotype . Holotype and paratype slide CRBA-90749 saved in the collection of the Centre de Recursos de Biodiversitat Animal , Faculty of Biology, University of Barcelona (http://www. crba.ub.edu); other paratypes kept in the E. Mateos’ collection (lot LP108 ) .

Other material. 5 specimens on slides and 1 specimen preserved in absolute alcohol, Las Hoyuelas , Sinarcas, Valencia ( Spain), 840 m above sea level, lat/long coordinates N39.765328 W1.226981, on herbaceous vegetation, hand collecting, 02.iv.2007, leg. E. Mateos, all material kept in the E. Mateos’ collection (lot LP122 ) .

Diagnosis. With dark blue pigment on Ant.II–IV, dorsal and ventral sides of Th.III to Abd.III (and with pale pigmentation on Abd.IV–V), coxae I–III, and ventral tube. Th.II sligthly projecting over head. Ant.I–II, legs, ventral tube and posterior region of manubrium with scales. Labial chaetotaxy M 1 M 2 REL 1 L 2, R shortened. Dorsal cephalic and body macrochaetae formula as A 0 [A]A 2 A 3 Pa 5 /00/0101+3. Abd.IV without chaeta s. Unguiculus lanceolate and with serrated outer margin.

2a

Molecular diagnosis. This species includes all populations that cluster with CoxII and EF sequences of the individuals LP108-1 to LP108-5 ( Table 1 ), with significant support in an adequate molecular delimitation model.

Etymology. The species name refers to the dark blue colour present only on part of the body. In Latin “semi” means half, and “coloratus” means pigmented.

Description. Holotype body length (without head nor furca) 1.5 mm, paratypes 1.5–1.8 mm. Body colour pattern ( Fig. 41 ) with dark blue pigment on the dorsal and ventral sides of Th.III to Abd.III (and with pale pigmentation on Abd.IV–V), Ant.II–IV (on Ant.II only in apical portion), coxae I-III, and ventral tube; densely black pigmented ocular areas. Mesothorax slightly projected over the head.

Antenna with scales on dorsal region of Ant.I–II. Ratio antenna:cephalic diagonal = 1.8–1.9, ratio Ant.I:II:III: IV as 1:1.8:1.8:2.7. Basis of Ant.I dorsally with three microchaetae arranged in triangle (Ant.I-organ); apex of Ant.I with a short curved S-chaeta in the membranous area of the ventral region. Ant.III organ composed of two subcilindrical and curved sensory rods. Ant.IV without apical bulb. 8+8 eyes; eyes A–F of equal size, eyes G and H a little bit smaller, ratio A/F and A/G = 1.2.

Clypeus ( Fig. 42 ) with three prefrontal chaetae (1 pf0 and 2 pf1), five facial chaetae (central one shorter), and four lateral chaetae (2 L1 and 2 L2), all these chaetae ciliated. Prelabral and labral chaetae in typical number 4/554 ( Fig. 42 ), prelabral chaetae ciliated, labral setae smooth, apical row branched ( Fig. 43 ), inverted U-shaped labral apical intrusion, four rounded labral papillae with a central very small pointed expansion (difficult to see in several specimens, Fig 43 ). Maxillary palp outer lobe with smooth apical appendage and basal chaeta, and three smooth sublobal appendages ( Fig. 44 ). Lateral process of outer labial papilla finger-shape, slightly curved, tip not reaching apex of papilla ( Fig. 45 ).

Labial and postlabial chaetotaxy as in Fig. 46 ; with five smooth proximal chaetae at the base of labial palp; labial anterior row formed by smooth chaetae (a1–a5), posterior row formed by ciliated chaetae with formula M 1 M 2 REL 1 L 2; chaeta R half in length of chaeta M 2, ratio M / R ≈ 2; postlabial chaetotaxy with all chaetae ciliated, row I (along ventral cephalic groove) with 4 chaetae.

Dorsal cephalic macrochaetae formula A 0 A 2 A 3 Pa 5, but also with pair of smaller supplementary macrochaetae A 2a between A 0 and A 2; maximum number of macrochaetae An on head 13+13 ( Fig. 47 ). Interocular chaetotaxy with s, t, p ciliated chaetae and 2–3 scales..

Dorsal body macrochaetae formula 00/0101+3 (macrochaetae m3 on Abd.II, and Sm+B4, B5, B6 on Abd.IV). Dorsal chaetotaxy of Th.II–III and Abd.I as in Figs 48–50 . Th.II with 2 lateral S-chaetae (al and ms) and without macrochaetae in dorsal position. Th.III with a lateral sensillum (al) close to several ciliated chaetae. Abd.I with a lateral S-microchaeta (ms) external to a6. Chaetotaxy of Abd.II–III as in Figs 51–52 . Abd.II chaeta ml present or absent depending on the specimens, chaeta p5p present; macrochaeta m3 with socket diameter 1.3 times higher than macrochaeta m5. Abd. III chaetae mi and d3 present in all specimens, with S-chaetae as and ms. All chaetae associated with the trichobothria on Abd.II–III strongly ciliated and partially fan-shaped (widened in the center). Chaetotaxy of Abd.IV as in Fig. 53 ; macrochaetae Sm, B4, B5, B6, D3, E2, E3, E4, F1, F2, F3 broader and with broad socket; macrochaetae T6, T7, D2, De3, E1, E4p, Fe4, F3p shorter or longer but always thinner and with socket of minor diameter; macrochaeta F2 inserted above macrochaeta E3; the ratio of distances between macrochaetae Sm–B4 / B4–B6 is 0.7–0.9; the ratio of distances between macrochaetae B4–B5 / B5–B6 is 1.3–1.8; accessory chaeta s associated with trichobotrium T2 absent; chaetae a, D1, m, pe and pi associated with trichobotria T2 and T4 strongly ciliate and widened in the center; sens chaetotaxy composed of 2 anterior dorsomedial elongate S -chaetae, and short chaetae as and ps; posterior margin with 5+5 smooth mesochaetae; lateral region without pseudopori on BP4. Dorsal chaetotaxy of Abd.V with S-chaetae as, acc.p4 and acc.p5 ( Fig. 54 ).

Legs with scales except in claws. V-shaped trochanteral organ formed by a maximum of 15 smooth straight chaetae ( Fig. 55 ). Unguis with basal pair of teeth at 50% from base of the inner edge, and with two inner unpaired teeth at 64% and 82% from base of the inner edge respectively; one external tooth and a pair of lateral teeth also present. Unguiculus lanceolate with finely serrated outer margin. Tibiotarsal tenent hair spatulate and smooth ( Fig. 56 ); ratio of tibiotarsal tenant hair / unguis inner edge ≈ 1; ratio of supra-empodial chaeta / unguiculus ≈ 1.

Ventral tube with 6+6 ciliated chaetae on anterior side (4+4 proximal, 2+2 distal) and 11+11 weakly ciliated chaetae on posterior side; scales present on anterior and posterior sides; lateral flap with a maximum of 23 laterodistal chaetae (17–21 ciliated and 2 smooth).

Manubrium with scales on anterior and posterior surfaces, with 2+2 ciliated apical chaetae on anterior side. The ratio manubrium:dens:mucro is 15:17:1. Manubrial plate with 3 inner chaetae and a maximum of 9 outer chaetae. Dental tubercle absent. Mucro with the two teeth of the same size, without spinelet on basal spine.

Pseudopores distribution on dorsal and ventral positions as in Figs 23a–b .

Ecology and distribution. All specimens were obtained by beating the herbaceous vegetation.

Discussion. Morphological characters clearly assign Lepidocyrtus semicoloratus sp. nov. to the Lepidocyrtus lignorum -group (sensu Mateos 2011). By the characteristic body colour pattern, L. semicoloratus sp. nov. clearly differs from all the other species of the L. lignorum -group except L. instratus , with which the new species shares the same colour pattern design. With the current information about L. instratus , the only characters useful for differentiating this species and L. semicoloratus sp. nov. are 1) the dark pigmented buccal area in L. instratus (not pigmented in the new species), 2) the size and position of the basal pair teeth on the inner edge of the unguis (tiny and at 40% in L. instratus vs. higher and at 50% in the new species), and 3) the shape of the unguiculi (smooth in L. instratus vs. serrated in the new species). On the other hand, the type locality and the habitat of both species are so different that they could hardly be the same species. L. instratus comes from the Swiss Alps, at altitudes above 1600 m above sea level, and inhabiting under stones in snowy areas and in groundhog droppings. L. semicoloratus sp. nov. comes from Eastern Spain (with marked Mediterranean climate), at altitudes below 1000 m above sea level, inhabiting herbaceous vegetation (although it must also live in the soil and under stones) in areas dominated by holm-oak and pine forests. Other differences between all species included in the lignorum -group are summarized in Table 2 .

The three molecular species delimitation analyses carried out ( Fig. 1 ) suggest that the two populations studied of this new species (populations LP108 and LP122) may represent two different species. The detailed morphological study carried out with the specimens of these two populations has not detected any relevant difference that allows assigning each population to a different species. For this reason, we consider both populations as the same morphological species. The geographical distance that separates the two populations is about 375 km, so it is very likely that there has been no contact between them for quite some time, which would explain the genetic differentiation found between both populations.

Figures

FIGURE 1. Phylogenetic tree inferred with Maximum Likelihood (ML) using the Concatenated dataset. Stars at nodes correspond to ultrafast bootstrap values, and their size is proportional to the value, showing only values> 70%. Vertical bars to the right of the phylogeny correspond to the molecular species delimitation methods results (ASAP, bPTP and mPTP from left to right). Scale bar represents number of substitutions per site.

FIGURE 23. Lepidocyrtus fuscocephalus sp. nov, L. milagrosae sp. nov. and L. semicoloratus sp. nov.: Pseudopores distribution: a, dorsal pseudopores; b–c, ventral pesudopores.

FIGURE 41. Lepidocyrtus semicoloratus sp. nov.: Habitus lateral (specimen in alcohol, without scales).

FIGURES 42–46. Lepidocyrtus semicoloratus sp. nov.: 42, clypeal and labral chaetotaxy; 43, apical labral chaetae and papillae; 44, maxillary palp (right side); 45, outer labial papilla (right side); 46, labial and postlabial chaetotaxy (right side). Black dots––ciliated chaetae, cross––scales.

FIGURE 47. Lepidocyrtus semicoloratus sp. nov.: Dorsal head chaetotaxy (left side). Broad circles––long ciliated macrochaetae, small circles––short ciliated macrochaetae.

FIGURES 48–50. Lepidocyrtus semicoloratus sp. nov. dorsal chaetotaxy (left side): 48, Th.II, 49; Th.III; 50, Abd.I. Circles–ciliated chaetae.

FIGURES 51–52. Lepidocyrtus semicoloratus sp. nov. dorsal chaetotaxy (left side): 51, Abd.II; 52, Abd.III. Broad circles–broad ciliated macrochaetae, small circles––thin ciliated macrochaetae.

FIGURE 53. Lepidocyrtus semicoloratus sp. nov.: Abd.IV chaetotaxy (left side). Broad black circles––broad ciliated macrochaetae, small black circles––thin ciliated macrochaetae.

FIGURES 54–56. Lepidocyrtus semicoloratus sp. nov.: 54, Abd.V chaetotaxy (left side), broad circles––long ciliated chaetae, small circles––short ciliated or smooth chaetae; 55, trochanteral organ; 56, third leg unguis and unguiculus.