Dicranocentrus amazonicus, Bellini, Bruno Cavalcante, Morais, José Wellington De & Oliveira, Fábio Gonçalves De Lima, 2013

Bellini, Bruno Cavalcante, Morais, José Wellington De & Oliveira, Fábio Gonçalves De Lima, 2013, A new species of Dicranocentrus Schött (Collembola, Entomobryidae, Orchesellinae) from Brazilian Amazon, Zootaxa 3709 (3), pp. 296-300 : 296-297

publication ID	https://doi.org/ 10.11646/zootaxa.3709.3.8
publication LSID	lsid:zoobank.org:pub:FCF94D38-A4A6-4F3A-95E9-4091CFB6D2C2
DOI	https://doi.org/10.5281/zenodo.6151555
persistent identifier	https://treatment.plazi.org/id/0B1487C9-FFEC-6D28-FF66-BFA5300BF97C
treatment provided by	Plazi
scientific name	Dicranocentrus amazonicus
status	sp. nov.

Treatment

Dicranocentrus amazonicus sp. nov.

Figs. 1–3 View FIGURE 1 View FIGURE 2. D View FIGURE 3. D

Type material. Holotype female, Brazil, Amazonas, Manaus, Reserva Ducke, 07-xi-2010. Oliveira, F.G.L. col. Paratypes 7 females and 5 males, same data as Holotype. Type material deposited at INPA Entomological Collection, ZIP Code 96067-375, Manaus, AM, Brazil.

Description. Total body length of Holotype excluding antennae and furca 1.73 mm. Entomobryid habitus ( Figs. 1 View FIGURE 1 , 2 View FIGURE 2. D A). Colour of alcohol fixed and mounted specimens pale yellow with dark blue pigment covering antennae, eye patches, and diffuse blue pigment on legs and lateral borders of Abd. IV ( Fig. 1 View FIGURE 1 ). Apically rounded or truncated brownish scales covering antennae, head, dorsal Th. II, III, dorsal Abd. I–V, legs and ventral furcula none on legs or antennae. Antennae divided into six antennomeres, Ant. V and VI annulated ( Figs. 2 View FIGURE 2. D B and 2C), without apical bulb or pin setae ( Fig. 2 View FIGURE 2. D C). Eye patches oval with 8+8 lenses, the largest A and smallest G ( Fig. 2D View FIGURE 2. D ). Presence of three interocular multiciliated mesochaetae ( Fig. 2D View FIGURE 2. D ). Pre-labral and labral setae normal, not bifurcated, smooth (one row of setae showed in Fig. 2 View FIGURE 2. D E). Labral papillae as shown in Fig. 2 View FIGURE 2. D E. Maxillary palp as shown in Fig. 2 View FIGURE 2. D F. Labial triangle setae M1 and E multiciliated others smooth, setae r shorter than E but not reduced ( Fig. 2 View FIGURE 2. D G). Meta-trochanteral organ with approximately 30 short spines ( Fig. 3 View FIGURE 3. D A). All ungues with two internal unpaired teeth ( Fig. 3 View FIGURE 3. D C). Unguiculi acuminate, with smooth edges ( Fig. 3 View FIGURE 3. D C). Tenent hairs capitate with smooth edges ( Fig. 3 View FIGURE 3. D C). Ventral manubrium region with 9+9 subapical setae.

Ventral tube without scales, bearing 18+18 smooth setae on posterior face ( Fig. 3 View FIGURE 3. D B).Two rows of short spines at internal proximal dens (19+19 spines) ( Fig. 3D View FIGURE 3. D shows only). Dens crenulate ( Fig. 3 View FIGURE 3. D E). Mucro typically bidentate bearing a mucronal spine ( Fig. 3 View FIGURE 3. D E). Dorsal head and body covered by few macrochaetae ( Fig. 3 View FIGURE 3. D F).

Etymology. The species is named after its type locality, Brazilian Amazonian rainforest.

Discussion. Dicranocentrus amazonicus sp. nov. has a more uniform colour pattern than other species recorded in Brazil, especially D. heloisae . These two species also have dissimilar patterns of dorsal chaetotaxy ( Arlé & Mendonça 1982). Dicranocentrus amazonicus sp. nov. has small number of spines on dens, hile Dicranocentrus silvestrii , D. termitophilus and D. heloisae have more than 50 spines, distributed in three or more rows, while D. amazonicus sp. nov. has approximately 19 spines, arranged in only two short rows.

The overall dorsal chaetotaxy D. amazonicus sp. nov. has similarities with other two Neotropical species of the genus, D. marias Wray and D. paramoensis Mari-Mutt, 1983 ( Mari-Mutt 1979, 1983). These three species have a small number of macrochaetae dorsally on head, especially on the posterior half, combined with few macrochaetae on each thoracic and abdominal segment. Dicranocentrus amazonicus sp. nov. is distinguished by an absence of macrochaetae on the posterior half of dorsal head and a combination of few macrochaetae on Th. III and Abds I–III, which are especially uncommon on Abd. II, where the new species has only 1+1 macrochaetae, compared to the more common 2+2 or more macrochaetae in other species of the genus ( Mari-Mutt 1979, 1983).

The resemblance of D. amazonicus sp. nov. to D. marias , in particular in head chaetotaxy, puts the new species in the marias- group, as proposed by Mari-Mutt (1979) which has only been reported so far from Central America. Dicranocenterus amazonicus sp. nov. and D. paramoensis , from Venezuela, expand the distribution of marias -group ( Mari-Mutt 1979, 1983).

Habitat. Dicranocentrus amazonicus sp. nov. was collected in the wet season from dead foliage and soil samples in the Reserva Ducke, approximately 20 km from the urban centre of Manaus municipality, State of Amazonas. The area is approximately 100 km ² and a conservation unit of the Brazilian Amazon rainforest. The climate is “Am” (Equatorial monsoonal or Tropical wet climate) following Koeppen’s system, which is represented by a hot equatorial climate with high rainfall during a longer wet season ( Kottek et al. 2006).