Matta pititinha,

Brescovit, Antonio D. & Cizauskas, Igor, 2019, Seven new species of the spider genus Matta Crosby from caves in the State of Minas Gerais, Brazil (Araneae, Tetrablemmidae), Zootaxa 4559 (3), pp. 401-444: 411-416

publication ID

https://doi.org/10.11646/zootaxa.4559.3.1

publication LSID

lsid:zoobank.org:pub:10CDA291-A32F-4954-9B80-E33579AF46E3

persistent identifier

http://treatment.plazi.org/id/038887C8-E760-FF82-FF0D-D675FBD21DE7

treatment provided by

Plazi

scientific name

Matta pititinha
status

sp. n.

Matta pititinha  sp. n.

Figures 6View FIGURE 6 ̄9, 30B.

Types. Male holotype from Cave HOL_014 (44°03'54"W, 21°10'58"S) and female paratype from Cave HOL_020 (44°03'59"W, 21°11'06"S), Prados, Minas Gerais, Brazil, 13-16/III/2017, Eq. Spelayon et al. col., deposited in IBSP 196139 and IBSP 196140, respectively.

Other material examined. Brazil. Minas Gerais: Prados, Cave HOL_017 (44°03'55"W, 21°11'04"S), 13-16/ III/2017, Eq. Spelayon et al. col., 1♂ ( IBSP 196141View Materials; photo)GoogleMaps  ; Cave HOL_020 (44°03'59"W, 21°11'06"S), 13-16/III/ 2017, Eq. Spelayon et al. col., 1♀ ( IBSP 196142View Materials; photo)GoogleMaps  ; Cave HOL_020 (7657089 596891), 19-26/IX/2017, 1♂ 1♀ ( IBSP 196145View Materials — SEM ♂ ♀)  ; Cave S3_HOL_004 (44°3'55''W 21°11'4''S), 22-30/VII/2014, 1♂ ( IBSP 186367View Materials)GoogleMaps  ; Cave S3_HOL_003 (44°3'55''W 21°11'4''S), 22-30/VII/2014, 1♀ ( IBSP 186368View Materials)GoogleMaps  ; Cave S3_HOL_002 (44°03'56"W, 21°11'04"S), 22-30/VII/2014, 1♀ ( IBSP 186369View Materials)GoogleMaps  ; Cave S3_HOL_021 (44°3'53''W 21°11'1''S), 22- 30/VII/2014, 1♀ ( IBSP 186370View Materials)GoogleMaps  ; Cave S2_HOL_008 (44°3'54''W 21°10'58''S), 22-30/VII/2014, 1♀ ( IBSP 186371View Materials)GoogleMaps  ; Cave HOL_021 (19-26/IX/2017), 1♂ 1♀ ( IBSP 196143View Materials)  ; Cave HOL_025 (7657253 597004), 19-26/IX/ 2017, 1♀ ( IBSP 196144View Materials)  ; Cave HOL_016 (7657150 597014), 19-26/IX/2017, 1♀ ( IBSP 196146View Materials)  , all collected by Eq. Spelayon; Conceição do Mato Dentro, Cave SERP _0135 (43°23'21''W 19°2'42''S), 04/XII/2013, M.T.M. Souza col., 1♀ ( IBSP 186379View Materials)GoogleMaps  ; Morro do Pilar, Cave SERP _0043 (43°15'49''W 19°11'0''S), 31/VIII/2 0 13, 1♀ ( IBSP 186380View Materials)GoogleMaps  ; Cave SERP _0050 (43°23'20"W, 19°02'08"S), 2013, 1♀ ( IBSP 186381View Materials)GoogleMaps  ; Cave SERP _0013 (43°20'34''W 19°5'55''S), VII/2013, 1♀ ( IBSP 186382View Materials)GoogleMaps  , all collected by L.G.S. Soares col.; Santo Antônio do Rio Abaixo, Cave SERP _0032 (43°16'31''W 19°9'58''S), 06/VII/2013, L.G.S. Soares col., 1♂ ( IBSP 186378View Materials)GoogleMaps  .

Etymology. The specific name is a noun in apposition that refers to an interjection used by people who live in the Brazilian State of Minas Gerais meaning “very small”, being the smallest described species of this genus.

Diagnosis. Matta pititinha  is distinguished from other Matta  species by having a combination of males with a retrolateral projection on leg I consisting of four conspicuous setae in large sockets ( Fig. 7EView FIGURE 7 ̄F) and an oval dorsal fold of the uterus externus in females ( Fig. 6FView FIGURE 6).

Description. Male (holotype, cave HOL_14, Barroso, Minas Gerais, Brazil). Cephalothorax and abdomen orange. Legs and palps yellow. Total length 0.96. Carapace projected, 0.42 long, 0.37 wide, with rugose surface ( Figs 6AView FIGURE 6, 7AView FIGURE 7 ̄D). Sternal surface reticulate ( Fig. 7DView FIGURE 7). Clypeus long, oblique, four times the diameter of the vestigial eyes ( Fig. 7DView FIGURE 7). Two vestigial frontal eyes ( Fig. 7A, DView FIGURE 7). Cheliceral apophysis short and rounded, with long hairs and translucent median lamina ( Fig. 7AView FIGURE 7 ̄D). Leg measurements: I—femur 0.26/ patella 0.11/ tibia 0.24/ metatarsus 0.13/ tarsus 0.22/ total 0.96; II—0.22/ 0.1/ 0.22/ 0.12/ 0.2/ 0.86; III—0.18/ 0.08/ 0.2/ 0.11/ 0.17/ 0.74; IV—0.36/ 0.11/ 0.31/ 0.19/ 0.21/ 1.18. Leg formula 4123. Leg I, spination absent; metatarsus narrowed at base ( Fig. 7EView FIGURE 7). Abdomen ovoid, large sclerotized plate covering dorsal surface ( Figs. 6AView FIGURE 6, 8HView FIGURE 8); ventrally covered by four sclerotized plates. Abdominal plates: large pulmonary plate with rounded anterior margin, surrounding pedicel and bearing oval book-lung plates, followed posteriorly by narrow and suboval postgenital plate, rectangular preanal plate, and conical anal plate surrounding spinnerets; laterally with four pairs of narrow plates, most ventral pair very short than others ( Fig. 8HView FIGURE 8), and a line of the four epiandrous spigots.

Male palp: femur with three long setae, with median short and projected salient plates ( Fig. 8GView FIGURE 8); tibia strongly swollen, rounded posteriorly; cymbium small; bulbus pear-shaped, with conductor with elevated border in the retrolateral side, involving the base of the long and sinuous embolus, enlarged at apex, with acute and coiled basally laminar projection ( Figs 6BView FIGURE 6 ̄C, 8A–F).

Female (Paratype; HOL_020, Barroso, Minas Gerais, Brazil). Coloration pattern as in male, except legs orange ( Fig. 6DView FIGURE 6). Total length 1.11. Carapace as in male ( Fig. 9AView FIGURE 9 ̄B), 0.43 long, 0.37 wide. Clypeus and sternum as in male. Eyes as in male. Chelicerae as in male and with inconspicuous apophysis ( Fig. 9A, CView FIGURE 9). Endites and labium as in male. Leg measurements: I—femur 0.34/ patella 0.12/ tibia 0.26/ metatarsus 0.17/ tarsus 0.21/ total 1.1; II— 0.28/ 0.11/ 0.23/ 0.16/ 0.24/ 1.02; III—0.27/ 0.1/ 0.2/ 0.16/ 0.21/ 0.94; IV—0.38/ 0.11/ 0.33/ 0.21/ 0.28/ 1.31.

Leg formula 4123. Leg spination absent. Pedipalpal tarsus ending in acuminate, smooth pit ( Fig. 9DView FIGURE 9). Abdomen with plates as in males ( Fig. 9EView FIGURE 9). Vulvae externally with ᴗ-shaped receptacle, visible by transparency ( Fig. 9FView FIGURE 9); narrow post genital plate and thin copulatory opening ( Fig. 6EView FIGURE 6). Internally with straight receptaculum and copulatory ducts; central process narrow, with half the length of the receptaculum ( Fig. 6FView FIGURE 6).

Natural history. Matta pititinha  sp. n. has morphological characteristics (ocular reduction/vestigial eyes) consistent with isolation to a subterranean environment, and we hypothesize that this species is a troglobite. Specimens were only found in the aphotic regions of caves among mixed lithological formations of iron and carbonate.

Distribution. Known from caves in the State of Minas Gerais, Brazil ( Fig. 30BView FIGURE 30).

Kingdom

Animalia

Phylum

Arthropoda

Class

Arachnida

Order

Araneae

Family

Tetrablemmidae

Genus

Matta