Entomobrya grisacea, Jordana & Greenslade, 2020

Jordana, Rafael & Greenslade, Penelope, 2020, Biogeographical and ecological insights from Australasian faunas: the megadiverse collembolan genus, Entomobrya (Entomobryidae), Zootaxa 4770 (1), pp. 1-104: 34-37

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Entomobrya grisacea

sp. nov.

Entomobrya grisacea   sp. nov.

( Figs 1N View FIGURE 1 , 4I View FIGURE 4 , 17 View FIGURE 17 A–F)

Holotype. Female, TAS, Cadbury Factory, Claremont, labelled as E. marginata   , - 42.792°S, 147.267°E, 12m asl, under vinyl tiles, 4.viii.1966 [ SAMA 22646–01 View Materials 01]. GoogleMaps  

Paratypes. Female, [ SAMA 2646–02 View Materials ]; male, [ SAMA 22646–03 View Materials ]; 9 specimens   in alcohol, same data as holotype, [ SAMA 22646–04 View Materials ] GoogleMaps   .

Description. Size. Length up to 1.52 mm excluding antennae, (n=3, males smaller than females at 1.3 vs 1.6). See for the measurements of the segments.

Colour. Granulated grey with dark grey antennae and anterior part of the head ( Figs 1N View FIGURE 1 , 4I View FIGURE 4 ).

Head. Eight eyes, G and H smaller than E and F size. Antennal length 620 μm (n=2), 1.74 times the length of the head (n=2). Ant IV with bilobed apical vesicle with pin chaeta beside it; relative length of Ant I/II/III/ IV=1/1.7/1.4/2.4 (n=2). Sensory organ of Ant III with straight rod–like small sensilla (8 µm) in addition to the normal guard sensilla (only two seen). Four labral multispinate papillae ( Fig. 17A View FIGURE 17 ). External process of papilla E reaching to the tip. Labral Mc formula: 4/554, 4 prelabral ciliated chaetae, labral chaetae smooth. Labial chaetae MREL 1 L 2 all appear smooth, only with one Mc M. Maxillary palp bifurcate with three sublobal chaetae.

Thorax and abdomen. Length ratio of Abd IV/III=4 (n=3). Tibiotarsus without differentiated chaetae, with exception of the presence of the smooth terminal chaetae on legs 3, characteristic for the genus. Unguis internal edge length 40 μm and 50 μm externally. Unguis ( Fig. 17F View FIGURE 17 ) with 4 teeth: paired two at 50 % from base, first unpaired tooth at 75 % from the base, the terminal one minute; lateral teeth below the level of paired ones, dorsal tooth more basal. Unguiculus lanceolated with external serrated lamella. Tenent hair clavate, longer than internal unguis edge. Trochanteral organ near to 20 spiny chaetae. Length of manubrium and dens 265 + 360=625 μm (n=3). Manubrial plate with 3 chaetae and 2 pseudopores. Mucro bidentate with apical tooth of similar size to subapical one, and with mucronal basal spine reaching the tip of subapical tooth. Mucronal length 11 μm. Length of smooth apical portion of dens 23 μm.

Macrochaetotaxy. Simplified Mc formula: 3,1,0,1,2/0,1/1,2/0,0,1/0,0,2,0,2. Head chaetotaxy ( Fig. 17B View FIGURE 17 ) Mc An 1, An 2, An 3a1 and An 3 present and with A 5 Mc on A2 area. M 1 to M 4 present as Mc. In sutural row present S 0, S 2, S 3, S 4, S 5i and S 5. Ps 2 and Ps 5 present.

Thoracic chaetotaxy of Th II ( Fig. 17C View FIGURE 17 ) only with Mc a 5 on T2 area present.

Abdominal chaetotaxy, a 2 and a 3 present on A1 area (has 1 or 2 mesochaeta or microchaetae) at Abd II, m 3 and m 3e Mc present on A2 area of Abd II ( Fig. 17D View FIGURE 17 ). On Abd III only m 3 Mc present on A5 area. Abd IV ( Fig.17E View FIGURE 17 ) with Mc B 4 and C 2a on A8 area; area A9 only with the pseudopore and A10 area with two Mc B 6 and A 6. Sensillary formula seen in some segments and as normal for the genus.

Remarks. The colour of the new species is not unique for the genus. It has been confused with E. marginata ( Tullberg, 1871)   . Its chaetotaxy is similar on Th II, Abd II and III with E. assuta   : 0,1/0(1mes),2/0,0,1 Mc respectively, but on Abd IV the new species has 4 Mc: A 6, C 2a, B 4 and B 6 while E. assuta   has 3: A 6, B 5 and B 6.

Etymology. The species name refers to its colour.