Americanura denisi, Palacios-Vargas & Mejia-Recamier & Vázquez, 2017

Palacios-Vargas, José G., Mejia-Recamier, Blanca E. & Vázquez, M. Magdalena, 2017, Two new species of Americanura (Collembola: Neanuridae) from Belize, Central America, Florida Entomologist 100 (2), pp. 310-310 : 310-

Americanura denisi sp. nov. ( Figs. 4–6 )

TYPE MATERIAL

HOLOTYPE female: 4 paratype females, 1 paratype male. All the type material will be kept at senior authors’ institution. Type Locality: BELIZE, Chikibul National Park, ex litter, 12 Nov 1998, ex litter, col. M. Vázquez, H. Klompen, C. Chargoy.

DESCRIPTION

Length 1.2 mm (range 1.3–1.6 mm; n = 3). Color white in alcohol. Granulations fine, about half size of 1 eye. Tubercles well developed, cephalic tubercles B not coalesce, and those of Abd IV, De, DL, and L fused. Head seta F short (93 µ m). Four kinds of body setae, relatively short and slightly barbulated macrosetae ( BM on Di tubercle / Th II, III; Abd I and IV) 119, 111; 111 and 128 µ m, short barbulated mesosetae (bme) 83 µ m (range 67–86 µm), and M 122 µ m (range 109–130 µm) nearly smooth with few barbulations, microsetae 38 µm (range 33–45 µm) besides sensorial seta (ss) around 100 µm ( Fig. 5 ).

Ant I with 7 setae, 3 are dorsal BM, Ant II with 11 setae, 4 dorsal weakly barbulated. Ant III sensorial organ with 2 globular sensilla in a cuticular fold, and 2 guard sensilla. Sgd slightly curved and as long as Sgv, 1 microsensillum ventro-external. Ant IV typical for genus ( Fig. 4 ) with sensilla S7 hypertrofied and S1 and S2 subequal to others.

Eyes 2 + 2 with dark pigment. Setae Ocm and Ocp short (99 µm). Mandibles with 3 teeth, maxillae styliform. Head with tubercles well developed, chaetotaxy in Fig. 2 and Table 3.

Tibiotarsi I, II and III without tenent hairs, with 18, 18, and 17 setae, respectively. Thoraxic and abdominal chaetotaxy in Figs. 5 and 6 . The total chaetotaxy is shown in Tables 3 and 4.

Ventral tube with 4 + 4 setae, the 2 distal setae subequal in size. Female genital plate with 3 + 3 pregenital seate, 20 to 23 circumgenital, 2 eugenital setae. Furcal vestige without microsetae.

ETYMOLOGY

Species is named afer Dr. Edouard Denis, for his contributions to the Collembola of Central America.

REMARKS

Americanura denisi sp. nov. has short and not heavily barbulated setae, Di setae formula 011/1111, presents cephalic setae “A”, has 2 ocular setae and there is not any fusion of DL and L tubercles on Abd III and IV. In addition, it has 2 setae between the ss of Abd V.

Americaura denisi sp. nov. is very closely related to one group of species that share a similar reduced chaetotaxy of the thorax and abdomen: A. banksi ( Denis, 1933) , A. bara ( Christiansen and Bellinger, 1980) , A. castagnorum Palacios-Vargas, Simón Benito, Paniagua Nunca- mendi, 2009, A. interrogator ( Cassagnau and Palacios-Vargas, 1983) , A. setafoliacea ( Cassagnau and Palacios-Vargas, 1983) , and A. sotanophila ( Cassagnau and Palacios-Vargas, 1983) . It differs very clearly from A. setafoliacea from Los Tuxtlas, Veracruz ( Mexico), which has palmate setae on head and thorax, and from A. sotanophila from Querétaro ( Mexico), which is much smaller (0.9 mm) and has only 1 + 1 seta be- tween the ss on Abd V. Americaura denisi sp. nov. differs from A. castagnorum from Panama in having a more abundant cephalic chaetotaxy (with head seta A and Ocp). Head tubercles Di, De and L are not well developed and are fused. Differences among these new species and the most similar taxa are shown in Table 5.

Variation: The presence of 2 abdominal bifurcate setae in 1 speci- men was the most outstanding variation observed.

Figures

Figs. 4–6. Americanura denisi sp. nov. 4, antennal dorsal chaetotaxy; 5, head and thorax chaetotaxy; 6, abdominal chaetotaxy.

Figs. 1–3. Americanura belicensis sp. nov. 1, antennal dorsal chaetotaxy; 2, head and thorax chaetotaxy; 3, abdominal chaetotaxy.