Bagnallella sedecimoculata (Salmon, 1943)

Potapov, Mikhail, Deharveng, Louis & Janion-Scheepers, Charlene, 2021, Taxonomy of the Proisotoma complex. VI. Rediscovery of the genus Bagnallella Salmon, 1951 and epitoky in Bagnallella davidi (Barra, 2001), comb. nov. from South Africa, ZooKeys 1072, pp. 185-204 : 185

Bagnallella sedecimoculata (Salmon, 1943)

Figure 2

Folsomia sedecimoculata Salmon, 1943

Holotoma sedecimoculata (Salmon, 1943)

Proisotoma sedecimoculata (Salmon, 1943)

Material examined.

South Africa, Western Cape, Stellenbosch, Jonkershoek Nature Reserve, canyon to waterfall, SAF-086, 34.005570°S, 18.992067°E, 15/03/2008, forest litter, Berlese, L.D. and A.B. leg.; Somerset , Helderberg , SAF-107, SAF-109, SAF-116, 34.040883°S, 18.873649°E, alt. 600 m, 04/03/2009, native forest litter, L.D. and A.B. leg.; Cape Town, Wynberg, Table Mountain , second collapse, SAF-141, 33.987637°S, 18.405750°N, alt. 725 m, 10/03/2009, native forest litter, L.D. and A.B. leg.; Constantia, Silvermine, in a small forest patch above Tokai, SAF-235, 34.038273°S, 18.395478°E, alt. 390 m, 06/11/2010, dead wood, D. Porco leg.; Kalk Bay , Echo Valley , Spes Bona forest, SAF-555, 01/03/2019, Afromontane forest , moss on rock, L.D. and A.B. leg .

New Zealand. NZL-049, Rotoiti: Lakes Rototongata and Rotoatua, 08/01/1996, primary forest, litter, L.D. and A.B. leg.

Australia. Victoria, July 2010, University Ballarat, St. Helens , 37.629979°S, 143.890801°E, Eucalyptus plantation, moss, P. Greenslade. leg.

Macquarie Island, Bauer Bay , 54.5549°S, 158.8760°E, April 2016, Turf sample, Berlese extraction, L. Phillips leg.

Diagnosis.

Maxillary palp bifurcate, two prelabral chaetae. Dens slender, with 16-20 anterior chaetae. Mucro bidentate. Anterior side of manubrium with 1+1 chaetae. 33/22235 s and 10/100 ms on body. Without ventral chaetae on Th.III.

Description.

Colour grey. Cuticle outwardly smooth. 8+8 ocelli, G and H smaller. PAO about as long as 0.8 Ant. I and as 1.1-1.3 Claw III. Maxillary outer lobe with four sublobal hairs and bifurcate maxillary palp. Labral formula as 2/554. Labium full set of guards (e7 present), three proximal and four basomedian chaetae. Ventral side of head with 4-5+4-5 postlabial chaetae. 11 chaetae on Ant.I, with three basal micro s-chaetae (bms), of which one bms large, and two ventral s-chaetae (s), Ant.II with three bms and one laterodistal s, Ant.III with one bms and six distal s (including two lateral). Thorax without ventral axial chaetae.

Macrochaetae weakly differentiated, medial ones on Abd.V as long as 0.4-0.5 of tergal midline. S-chaetae weakly differentiated. S-formula as 43/22235 (s), 10/100 (ms). S-chaetae on Abd.I-III in mid-tergal position. General pattern of chaetotaxy as in B. dubia (Fig. 4 ). Ti.1-2 with 21 chaetae, Ti.3 with few additional chaetae. Tibiotarsal tenent chaetae not developed. Ventral tube with 4+4 laterodistal and usually with six posterior chaetae (four in a transversal row). Retinaculum with 4+4 teeth and two chaetae. Anterior furcal subcoxae with 11-15, posterior ones with 7-9 chaetae. Anterior side of manubrium with 1+1 distal chaetae (Fig. 2 ). Dens with 17-19(16-20) anterior chaetae, posterior side of dens with crenulation and seven chaetae (Fig. 2 ). Mucro bidentate. Ratio of manubrium: dens: mucro = 5.3-6.3: 5.9-6.7: 1.

Discussion.

Bagnallella sedecimoculata was described from New Zealand and was designated as type species for the genus Bagnallella (see the discussion to the genus above). The type specimen from New Zealand was studied ( Potapov and Janion-Scheepers 2017), although only one generic character (separation of two abdominal segments) was proven. The redescription given above is based mostly on the South African material which looks conspecific to one individual in hand from New Zealand (L.D. and A.B. leg.). Bagnallella sedecimoculata resembles B. dubia and differs by ventral chaetae on Th.III (absent vs present) and a few more anterior chaetae on dens (16-20 vs 12-16). The latter character is not stable enough to separate the two species.

Distribution.

Probably widely distributed. So far with scattered records in the South Hemisphere (New Zealand, Australia, South Africa, Macquarie Island).

Figures

Figures 1 - 4. S-patterns of Abd. IV-VI in the genera Cryptopygus Bagnallella and Scutisotoma (1) B. sedecimoculata (2) and B. dubia (3, 4) 2, 3 furca, anterior view 4 macrochaetae and s and ms-chaetae on body. s = s-chaetae, ms = ms-chaetae.