Cryptopygus tingus , Gabriel C. Queiroz & Maria Cleide De Mendonça, 2010

Gabriel C. Queiroz & Maria Cleide De Mendonça, 2010, Two new Isotomidae species (Collembola) from Espírito Santo State, Brazil, Zootax 2480, pp. 37-44: 37-42

publication ID

http://doi.org/ 10.5281/zenodo.893964

persistent identifier

http://treatment.plazi.org/id/03D987A7-C146-0062-4ED9-F897FCE9FECA

treatment provided by

Plazi

scientific name

Cryptopygus tingus
status

sp. nov.

Cryptopygus tingus  sp. nov.

Figs 1–13View FIGURES 1 – 13, Tab. 1

Type material. Holotype female. Brazil, Espírito Santo State, Sooretama municipality, Sooretama Biological Reserve (ICMBio), forest litter of the Atlantic Forest , about 200 m above the sea level and 40km from the coast line. Local coordinates: 19°3'8.53"S, 40°8'56.12"W, 25.iv.2008, collection number CM 1958, Gabriel C.GoogleMaps 

Queiroz coll. Paratypes: 9 (Nº 1958 CM/ MNRJAbout MNRJ) on slides, same date as holotype. Deposited at Museu Nacional do Rio de Janeiro, Brasil.

Description. Body length of holotype 0.58 mm, paratypes 0.35–0.65 mm. Color white, no trace of pigment. Tegumentary granulation very fine, without craters.

Body chaetotaxy. Common setae smooth and acuminate. Macrosetae stiff, becoming increasingly longer towards the last abdominal tergites ( Figs 1, 2View FIGURES 1 – 13). Formula of macrosetae per half tergite as: 11/33347. Macrosetae of abdominal segments V –VI measuring about 50 µm, almost as long as antennal segment IV (55 µm). Axial setae per half tergites as: 75/33334, abdominal tergite V –VI with unpaired setae a0, m0 and p0 measuring 20, 40 and 15 µm, respectively ( Fig. 2View FIGURES 1 – 13). Sensillar formula per half tergites as: 22/12232 (s), 10/ 00000 (ms); microsensillum on thorax II almost indistinguishable from nearby sensilla. Dorsal sensilla on abdominal segment V –VI smooth and oval ( Fig. 1View FIGURES 1 – 13); ventral sensilla (1+1) near genital opening ( Fig. 13View FIGURES 1 – 13).

Antennae. Slightly longer than head diagonal, with common, acuminate setae of different sizes. Ratio antennae: head diagonal = 1.2:1. Antennal segment I with about 16 setae, 2 basal microsetae (one ventral and one dorsal) and 2 sensilla in ventroapical position ( Fig. 4View FIGURES 1 – 13). Antennal segment II with about 23 setae, 4 basal microsetae (one dorsal, one ventral and 1+1 lateral), and one long lateral external sensillum. Antennal segment III with about 25 setae; sensory organ consisting of 2 small freely exposed sensilla, 2 guard sensilla and one external microsensillum; no basal microseta ( Fig. 5View FIGURES 1 – 13). Antennal segment IV with subapical organite protected by one curved setae, 7–8 cylindrical sensilla; without apical papilla ( Figs. 5, 6View FIGURES 1 – 13). Ratio of antennal segments I:II:III:IV= 1:1.5:1.8:2.8.

Head. Without eyes. Postantennal organ large and oval, as long as the width of antennal segment I, surrounded by 6 guard setae ( Fig. 3View FIGURES 1 – 13). Mouth parts of chewing-type. Labrum with 3 prelabral and 5,5,4 labral setae. Maxillary capitulum with six fringed lamellae and two subequal teeth. Maxillary outer lobe bifurcated, with three sublobal hairs and one basal seta. Labial palp with 5 papillae and 15 setae (a1, b1–4, d1–4, e1–6), one lateral process smaller than half of papilla E. Hypostomal setae distinct, H thick blunt, smaller than others, h1 and h2 long and curved (h2 with enlarged base) ( Fig. 7View FIGURES 1 – 13). Head with 5+5–4+4 setae along linea ventralis.

Appendages. Unguis small, without internal tooth. Unguiculus toothless, short and lanceolate. Tibiotarsi I –III with 24, 24, 30 setae, respectively; tenent hair pointed, not differentiated from other setae; distal whorl with 7 setae on tibiotarsi I –III ( Fig. 8View FIGURES 1 – 13). Tibiotarsus II with B4 and B5 setae.

Ventral tube with 4+4 apical and 3+3 posterior setae, without anterior setae ( Fig. 9View FIGURES 1 – 13). Retinaculum with 4+4 teeth and one seta on corpus ( Fig. 10View FIGURES 1 – 13). Anterior furcal subcoxa with about 12 setae, posterior with 5 setae. Manubrium with 1+1 distal long seta on anterior side, 14+14 setae on posterior side and 2+2 small lateral setae. Dens long and crenulated, with 24 anterior and 6 posterior setae ( Fig. 11View FIGURES 1 – 13). Mucro bidentate, very small, without setae ( Fig. 12View FIGURES 1 – 13). Ratio manubrium:dens:mucro = 12:18:1. Male genital opening as in Fig. 13View FIGURES 1 – 13.

Discussion. Cryptopygus tingus  sp. nov. belongs to a group of species without eyes and pigment (sensu Thibaud 1996), which includes C. albaredai (Selga, 1962)  , C. axayacatl Palacios-Vargas & Thibaud, 2001  , C. benhami Christiansen & Bellinger, 1980  , C. bibasiosetis Potapov & Stebaeva, 1999  , C. delamarei Poinsot, 1970  , C. caussaneli Thibaud, 1996  , C. debilis (Cassagnau, 1959)  , C. exilis (Gisin, 1960)  , C. scapelliferus (Gisin, 1955)  and C. tribasiosetis Potapov & Stebaeva, 1999  . Among these species, C. benhami  is the only that presents an internal tooth on unguis. Table 1 lists the characters that distinguish these species.

In the group of blind species Cryptopygus tingus  sp. nov. is more related to C. debilis  due to similarities in the shape and size of the sensillum on abdominal segment V –VI, the number of dorsal and lateral manubrial setae, the shape and size of the mucro, according to the redescription of C. debilis  by Ellis (1976). Nevertheless, C. debilis  has craters on abdominal segment V –VI, 2+2 anterior setae in the manubrium, a longer dens bearing 30 setae, and the macrosetae of body not so well developed. Unfortunately, the whole sensillar chaetotaxy of C. debilis  is unknown. Comparing the sensillar pattern of C. tingus  sp. nov. to some species of the mentioned group, which are included in Fjellberg (2007), it is possible to verify that C. scapelliferus  and C. albaredai  share a similar pattern with the new species by presence of the lateral sensilla (al) from thoracic segment II to abdominal segment I. However, C. scapelliferus  does not have the accp sensillum on abdominal segment II and both, C. albaredai  and C. scapelliferus  , have a microsensillum between the 2 sensilla on the abdominal segment III and 7 sensilla in the abdominal segment V –VI. One of these sensilla on abdominal segment V –VI of C. scapelliferus  and C. albaredai  is ventral, located near the base of manubrium and probably near to the genital opening of adults. Palacios-Vargas & Thibaud (2001), in the description of C. axayacatl  , also make reference to the presence of a ventral “microsensillum” in the abdominal segment V –VI which is close to the genital opening of an adult. The same sensillum was also observed in the new species. It is also worth noting that C. tingus  sp. nov. shares some other similarities with C. scapelliferus  like shape and size of mucro, number of anterior manubrial setae, number and position of setae on dens and also the fact that the macrosetae become longer towards the tip of the abdomen. According to Fjellberg’s drawing (2007: Fig. 46 F), C. scapelliferus  does not have the a0 seta on sixth abdominal segment, while p0 and m0 are present. In C. tingus  sp. nov. all 3 unpaired setae are present.

Etymology. From the indigenous brazilian language Tupi: tinga is a word that means “white”, in a reference to the absence of pigment of the new species.

MNRJ

Museu Nacional/Universidade Federal de Rio de Janeiro