Matta pititinha, Brescovit & Cizauskas, 2019

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

DOI

https://doi.org/10.5281/zenodo.5934735

persistent identifier

https://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 6 View 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 196141 View 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 196142 View Materials ; photo) GoogleMaps ; Cave HOL_020 (7657089 596891), 19-26/IX/2017, 1♂ 1♀ ( IBSP 196145 View Materials — SEM ♂ ♀) ; Cave S3_HOL_004 (44°3'55''W 21°11'4''S), 22-30/VII/2014, 1♂ ( IBSP 186367 View Materials ) GoogleMaps ; Cave S3_HOL_003 (44°3'55''W 21°11'4''S), 22-30/VII/2014, 1♀ ( IBSP 186368 View Materials ) GoogleMaps ; Cave S3_HOL_002 (44°03'56"W, 21°11'04"S), 22-30/VII/2014, 1♀ ( IBSP 186369 View Materials ) GoogleMaps ; Cave S3_HOL_021 (44°3'53''W 21°11'1''S), 22- 30/VII/2014, 1♀ ( IBSP 186370 View Materials ) GoogleMaps ; Cave S2_HOL_008 (44°3'54''W 21°10'58''S), 22-30/VII/2014, 1♀ ( IBSP 186371 View Materials ) GoogleMaps ; Cave HOL_021 (19-26/IX/2017), 1♂ 1♀ ( IBSP 196143 View Materials ) ; Cave HOL_025 (7657253 597004), 19-26/IX/ 2017, 1♀ ( IBSP 196144 View Materials ) ; Cave HOL_016 (7657150 597014), 19-26/IX/2017, 1♀ ( IBSP 196146 View 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 186379 View Materials ) GoogleMaps ; Morro do Pilar, Cave SERP _0043 (43°15'49''W 19°11'0''S), 31/VIII/2 0 13, 1♀ ( IBSP 186380 View Materials ) GoogleMaps ; Cave SERP _0050 (43°23'20"W, 19°02'08"S), 2013, 1♀ ( IBSP 186381 View Materials ) GoogleMaps ; Cave SERP _0013 (43°20'34''W 19°5'55''S), VII/2013, 1♀ ( IBSP 186382 View 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 186378 View 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. 7E View FIGURE 7 ̄F) and an oval dorsal fold of the uterus externus in females ( Fig. 6F View 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 6A View FIGURE 6 , 7A View FIGURE 7 ̄D). Sternal surface reticulate ( Fig. 7D View FIGURE 7 ). Clypeus long, oblique, four times the diameter of the vestigial eyes ( Fig. 7D View FIGURE 7 ). Two vestigial frontal eyes ( Fig. 7A, D View FIGURE 7 ). Cheliceral apophysis short and rounded, with long hairs and translucent median lamina ( Fig. 7A View 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. 7E View FIGURE 7 ). Abdomen ovoid, large sclerotized plate covering dorsal surface ( Figs. 6A View FIGURE 6 , 8H View 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. 8H View 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. 8G View 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 6B View FIGURE 6 ̄C, 8A–F).

Female (Paratype; HOL_020, Barroso, Minas Gerais, Brazil). Coloration pattern as in male, except legs orange ( Fig. 6D View FIGURE 6 ). Total length 1.11. Carapace as in male ( Fig. 9A View 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, C View 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. 9D View FIGURE 9 ). Abdomen with plates as in males ( Fig. 9E View FIGURE 9 ). Vulvae externally with ᴗ-shaped receptacle, visible by transparency ( Fig. 9F View FIGURE 9 ); narrow post genital plate and thin copulatory opening ( Fig. 6E View FIGURE 6 ). Internally with straight receptaculum and copulatory ducts; central process narrow, with half the length of the receptaculum ( Fig. 6F View 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. 30B View FIGURE 30 ).

Kingdom

Animalia

Phylum

Arthropoda

Class

Arachnida

Order

Araneae

Family

Tetrablemmidae

Genus

Matta