Cryptopygus bulbus, Potapov & Janion-Scheepers & Deharveng, 2020

Potapov, Mikhail B., Janion-Scheepers, Charlene & Deharveng, Louis, 2020, Taxonomy of the Cryptopygus complex. III. The revision of South African species of Cryptopygus and Isotominella (Collembola, Isotomidae), ZooKeys 945, pp. 99-127 : 99

Cryptopygus bulbus sp. nov. Figures 1 , 2 , 4 , 6-14

Type material.

Holotype and thirteen paratypes: South Africa • Western Cape, Cederberg Wilderness Area, Wolfberg Crags; 32.471507S, 19.278397E; 19 Feb 2011; C. Janion-Scheepers leg.; litter, Tullgren extraction; RSA11_CED002, deposited at SAMC • six paratypes on four slides and seven paratypes in ethanol; same locality • sixteen paratypes; Western Cape, Cederberg Wilderness Area; 32.310167S, 19.175183E; Oct. 2008; C. Janion-Scheepers leg.; pitfall trap; RSA08_CED001. Four paratypes deposited in ethanol at SAMC, five paratypes on three slides deposited at SMNG, seven paratypes on three slides at MSPU.

Other material.

South Africa • Western Cape, Mont Rochelle Nature Reserve, Franschoek; 33.902967S, 19.158950E; 06 Oct. 2008; C. Janion-Scheepers leg.; Erica site with Erica-Protea ( Ericaceae and Protacea ) mixed litter, litter trap; MR644, MR648 • Western Cape, Kogelberg Nature Reserve; 34.328083S, 18.962250E; 29 Aug. 2008; C. Janion-Scheepers leg.; Erica Site, Litter trap (K467), with Galenia litter.

Diagnosis.

With a globular retractile bulb on Ant. IV. Organite on Ant. IV chili-like. 6+6 ocelli. Maxillary palp simple. Two sublobal hairs. Anterior side of manubrium without chaetae. Tenaculum with one chaeta.

Description.

Body size 0.7-0.9 mm, habitus as in Figs 1 , 2 . Body with rather regular blue pigmentation, slender. Abd. V well separated from Abd. IV and fused with Abd. VI (Fig. 4 ). Cuticle “smooth”, with orthogonal primary granulation. Ocelli 6+6 arranged in anterior and posterior groups (Fig. 8 ), three in each. PAO more than twice as long as ocellus, 0.6-0.7 as long as width of Ant. I and 1.0-1.3 as long as inner unguis length. Maxillary head with unmodified lamellae. Maxillary outer lobe with two sublobal hairs, maxillary palp simple. Labral formula as 2/5,5,4, edge of labrum not reduced (Fig. 7 ). Labium with five usual papillae (A-E) and labial formula A1B3C0D4E6, guard chaetae e7 and b4 absent, three proximal and four basomedian chaetae. Ventral side of head with 4+4 chaetae. Ant. I with two ventral s-chaetae (s) and three small bms, two dorsal and one ventral, Ant. II with three bms and one latero-distal s, Ant. III with one bms and five distal s (including one lateral), without additional s-chaetae. S-chaetae on Ant. IV weakly differentiated. Organite long, of chili-like shape, set apart from subapical micro s-chaeta (Figs 9 , 10 ). A globular retractile bulb embedded at tip of antennae, near pin-chaeta (Figs 9 , 10 ).

Common chaetae often slightly serrated at the posterior part of Abd. V. S-formula as 4,3/2,2,2,3,5 (s), 1,0/1,0,0 (ms) (Fig. 7 ). Tergal s-chaetae much shorter than common chaetae and well distinguishable (Fig. 4 ). Medial s-chaetae on Th. II-Abd. III situated in mid-tergal position. On Abd. V, three dorsal s-chaetae (al, accp1, accp2) and two lateral ones slightly shorter (Fig. 6 ). Macrochaetae smooth and short, 1,1/3,3,3 in number, medial ones on Abd. VI 1.6-2.0 times longer than dens and 2.8-4.1 times longer than mucro. Foil chaetae at the tip of abdomen absent. Axial chaetotaxy as 5-6,4/3,3(4),3-4,4-6. Th. I and II without ventral chaetae, Th. III with 2+2 ventral chaetae (Fig. 1 ).

Unguis of normal shape, without teeth. Empodial appendage 0.5-0.7 as long as unguis. Tibiotarsi without additional chaetae on Leg I and II (21 chaetae), and with few ones on Leg III (>25), adult males with short thickened spurs on tibiotarsi III (Fig. 11 ). Tibiotarsal tenent hairs clavate, 1,2,2 on Tibiotarsi 1,2,3. Ventral tube with 3+3 laterodistal and 4-6 posterior chaetae, anteriorly without chaetae (Fig. 12 ). Tenaculum with 4+4 teeth and one chaeta. Anterior furcal subcoxa with 5-7, posterior one with three chaetae. Anterior side of manubrium without chaetae, posterior side with 4+4 laterobasal and 8-10 chaetae on main part, without lateral chaetae (Figs 13 , 14 ). Dens short, without crenulation, with one rigid and short anterior and three posterior chaetae. Mucro bidentate. Ratio manubrium: dens: mucro = 2.5-4.1: 1.7-2.2: 1.

Etymology.

The name is derived from the presence of apical bulb on Ant. IV.

Distribution and ecology.

Currently known to occur in the southern part of the Western Cape Province of South Africa, including Kogelberg, Franschoek and the Table Mountain area (Cape Town). All specimens were collected from leaf litter in indigenous vegetation.

Discussion.

The species differs from other representatives of the Cryptopygus complex, if not from all Isotomidae of the Southern Hemisphere, by the presence of a globular bulb at tip of the antennae. The taxonomical value of this character is not fully clear. In the Northern Hemisphere several unrelated genera also possess an apical bulb which is embedded on the tip of the antennae, for example Anurophorus Nicolet, 1842 (most of the species), Sibiracanthella Potapov & Stebaeva, 1994, Tuvia Grinbergs, 1962 and Vertagopus Börner, 1906 (few species). The antennal bulb of C. bulbus sp. nov. is set apart from the apex, which is unlike in the aforementioned taxa. The only exception found was in specimens observed from Orangekloof (Cape Town), where the apical bulb was less developed.

For other differences of the new species from congeners see the Discussion of C. abulbus sp. nov.

Figures

Figures 1 - 3. Appearance and macrochaetotaxy of C. bulbus sp. nov., ventral (1) and lateral (2) views, and C. abulbus sp. nov. (3).

Figures 4 - 5. Macrochaetotaxy and s-ms-pattern of C. bulbus sp. nov. (4) and C. abulbus sp. nov. (5). Abbreviations: msms-chaeta, ss s-chaeta.

Figures 6 - 14. C. bulbus sp. nov. 6 Abd. IV and fused Abd. V and VI 7 labrum, lateral view 8 ocelli, PAO and Ant. I 9, 10 apical part of Ant. IV, different views 11 tibiotarsus and claw of Leg III in adult male 12 ventral tube, ventral view 13 furcal area, ventral view 14 furca, lateral view. Abbreviations: ab apical bulb, org organit, sms subapical ms-chaeta, bms basal ms-chaeta, ss s-chaeta.