Two new species and new records of Neanuridae (Hexapoda: Collembola) from Brazilian central Amazonia
Author
Carolina da Rocha Neves, Ana
Author
Cleide de Mendonca, Maria
Author
Costa Queiroz, Gabriel
text
Zoologia
2019
36
1
8
http://dx.doi.org/10.3897/zoologia.36.e23269
journal article
http://dx.doi.org/10.3897/zoologia.36.e23269
1984-4689-36-1
BF0A73B54F694B36B822D66EA8BD859D
Friesea multiclavata
sp. nov.
Figs 1-6, 7-9, Tab. 1
Description
Body length: 0.51 mm (Holotype). Habitus cylindrical and robust, typical of
Friesea
. Color bluish-gray with ventral of head, legs and sternites white. Secondary granules moderately developed. Antennae shorter than cephalic diagonal. Ratio antenna: cephalic diagonal = 1: 1.4. Ant IV with apical bulb simple and subapically displaced on ventral side; subapical organite, dorsolateral S-microchaeta and 6 S-chaetae present dorsally (Fig. 1). Sensory organ of Ant III formed by five S-chaetae: two internal S-microchaetae bent externally and freely exposed; two subcylindrical guard S-chaetae and one smaller ventral S-microchaeta (Fig. 2). Ant I with 7 simple chaetae and Ant II with 11 chaetae, of which 10 are simple and one is strongly spatulate dorsoexternally (see detail in Fig. 7).
Head with 8+8 eyes in heavily pigmented eye-patch. Mandible strong with 5 unequal teeth; basal tooth measuring approximately twice the size of the others; maxilla head typical of the genus, with three lamellae; internal lamella with about 6 denticles (Fig. 3). Buccal cone short; Pre-labral/labral chaetae arranged according to the formula: 2/5,5,4. Labium typical of the genus, with papillated chaeta L, chaeta F about twice the length of E (Fig. 4).
Chaetotaxy of legs I, II, III. Subcoxae I 1,3,3; Subcoxae II 0,2,2; Coxae 3,6,7; Trochanters 5.4,4; Femora 11,10,10; Tibiotarsi 18,18,17, without M chaeta. Tibiotarsi I-III with 4,5,5 clavate tenent hairs, respectively (2 dorsal and 2 ventral on Tita I; 3 dorsal and 2 ventral on Tita II and III) (Figs 5, 6). Subcoxa I of legs I-III and lateral region of Abd V with hemispheric tegumentary protuberance constituted of primary granules (see detail of Fig. 7). Ungues toothless.
Dorsal body. Composed of short ordinary chaetae, slender S-chaetae, slightly longer than ordinary, and strongly clavate chaetae laterally on head and abdominal tergites IV-VI (Fig. 7). Head chaetotaxy composed of a0, d0, d2-5, sd1-5, oc1-3, c1-2, p1-2. Th I with 2+2 simple chaetae. Abd IV with 2+2 small clavate dorsolateral chaetae; Abd V with 2+2 long clavate dorsal chaetae; Abd VI with 10 strongly clavate chaetae arranged in three linear rows, as 4,4,2 (Fig. 7 and detail). Formula of S-chaetae by half tergite: 022/11111.
Ventral tube with 3+3 chaetae. Abdominal sternites II-V with 4+4, 5+5, 12+12, 5+5 chaetae, respectively (Fig. 8). Tenaculum and furca absent; furcal area with 2+2 microchaetae. Anal valves with 11-12 chaetae and one hr chaeta. Male genital plate with 2+2 pregenital chaetae, 4+4 eugenital and 9 circungenital chaetae (Figs 8, 9).
Material examined
Holotype male. BRAZIL, Amazonas State: Presidente Figueiredo municipality, forest leaf litter of Amazon Rainforest, coordinates
02°02'56"S
,
60°06'08"W
, 23.IV.2008, Hamada, Azevedo, Neiss, Silva & Meneses leg. (CM/ MNRJ slide number 2538).
Etymology
The specific name multiclavata is derived from Latin, meaning bearing nails, and is an allusion to the numerous clavate chaetae arranged along the tergites.
Remarks
Friesea multiclavata
sp. nov. can be included in the reducta-group, which is composed of 14 species, according to
Queiroz and
Mendonca
(2015)
, based on the following characters: 8+8 eyes and absence of furca and anal spines (Table 1). Despite the absence of anal spines, most species in this group, with the exception of
Friesea africana
Delamare Deboutteville, 1953, have some degree of chaetae modification on Abd VI. In this sense, the new species is unique within this group since it also presents modified chaetae on head and antennae.
Friesea multiclavata
sp. nov. is very similar to
Fr. albithorax
Massoud & Thibaud, 1980 (Antilles),
Fr. lobulata
Palacios-Vargas &
Diaz
, 1986 and
Fr. mucumontana
Palacios-Vargas &
Diaz
, 1986 (Venezuela) mainly for sharing the 2+2 chaetae on Th I, clavate chaetae on body and 18,18,17 chaetae on tibiotarsi I-III. However,
Fr. multiclavata
sp. nov. has a simple apical bulb, 4,5,5 tenent hairs on tibiotarsi and ungues without teeth while
Fr. lobulata
has a trilobed apical bulb, only two clavate tenent hairs on legs I-III and toothed unguis.
Friesea multiclavata
sp. nov. is uniformly bluish-gray colored, while
Fr. albithorax
presents white thoracic tergites and the rest of the body is grey. Moreover,
Fr. multiclavata
sp. nov. is unique among the four species here referred, by the 10 strongly clavate chaetae on Abd VI, while the others have six (
Fr. lobulata
and
Fr. mucumontana
) or eight (
Fr. albithorax
) clavate chaetae.
Friesea multiclavata
sp. nov. has an inconspicuous tegumentary protuberance on subcoxa I of legs I-III and ventrolaterally on Abd V (Fig. 7), also found in
Fr. reducta
and
Fr. boitata
. This structure was first mentioned by
Massoud and Thibaud (1980)
in specimens of
Fr. reducta
from Lesser Antilles. Later on,
Fr. boitata
was also found to possess the same structures on subcoxae I and Abd V. According to
Queiroz and
Mendonca
(2015)
, it is possible that these structures were not mentioned in other descriptions as they may have not been properly visualized.
Although there are no phylogenetic studies for Neotropical species of
Friesea
, the proposition of a group relying on morphological similarities, such as reducta-group, represents the first step towards a better understanding of the
genus'
morphological diversity in the biogeographical region. As proposed by
Queiroz and
Mendonca
(2015)
, it is possible to distinguish
"subgroups"
of species within this group based on the number of chaetae on Th I, being 2, 3 or 4 by half tergite. Despite that, we believe that the striking resemblance of these species, especially those
previously
mentioned with 2+2 chaetae on Th. I, suggests close relationship between them.
While further studies may clarify phylogenetic relationships, comparative morphological studies are still the mainframe for species recognition. In this sense, all described species in the mentioned subgroup can be distinguished mainly based on body chaetotaxy, especially chaetae morphology, such as clavate chaetae. This character is considered to be consistent and, therefore, it is widely used, especially for recently described species.
Figures 1-6.
Friesea multiclavata
sp. nov. holotype male: (1) Ant III-IV in dorsal view; (2) Ant III-IV in ventral view; (3) maxillae in dorsal view; (4) half labium in ventral view; (5) Tita II in ventrolateral view; (6) Tita II in dorsolateral view.
Table 1. Main characters of species of
Friesea
, belonging to reducta-group. Modified from
Queiroz and
Mendonca
(2015)
.
Th |
Tita |
Abd |
Fr. africana
|
Fr. albithorax
|
Fr. boitata
|
RJ |
Fr. bonariensis
|
Fr. josei
|
Fr. jurubatiba
|
RJ |
Fr. lobulata
|
Fr. marianoius
|
Fr. mucumontana
|
Fr. reducta
|
Fr. sensillata
|
Fr. steineri
|
Fr. tepetlana
|
Fr. tzontli
|
Fr. xitlensis
|
Fr. multiclavata
|
AM |