Matta nuusga, 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 : 431-432

Matta nuusga sp. n.

Figures 22 ̄25, 30C.

Types. Male holotype and female paratype from Pains, Minas Gerais, Brazil, R. Zampaulo col., deposited in IBSP 186406.

Other material examined. BRAZIL. Minas Gerais: Matozinhos, Cave MOC-N5, 01-08/VIII/2011, F.P. Franco & C.A.R. Souza et al. col., 1♀ ( IBSP 180289 ) ; Pains, Cave no name, 2013, A.P. Bueno et al. col., 1♀ ( IBSP 196135 ) ; Cave no name, no date, R. Zampaulo col., 1♀ ( IBSP 186402 ) ; Cave no name 2013, A. P. Bueno et al. col., 1♂ 1♀ ( IBSP 196129 ) ; Cave (no data), R. Zampaulo col., 2♂ ( IBSP 186401 ) ; Cave AMG-025 (20°22'29''S; 45°37'7''W) 17-29/ VI /2013, A. P. Bueno et al. col., 1♀ ( IBSP 186536 ) ; Cave AMG-05 (20°22'4''S; 45°37'0''W), 14/I-02/II/2013, A.P. Bueno et al. col., 2♂ ( IBSP 186537 ) ; Cave C6a, 4/XI/2005, M.E. Bichuette col., 1♀ ( IBSP 196168 ) ; Cave GE_32 (20°21'42''S; 45°36'26''W) 18/III-6/IV/2013, A.P. Bueno et al. col., 1♂ ( IBSP 196130 ) ; Cave GE_34 (20°22'6''S; 45°36'14''W), 15-27/VII/2013, A.P. Bueno et al. col., 2♀ ( IBSP 196136 ) ; Cave Gruta 13, IV/2008, E. O. Machado & J.P.P. Barbosa col., 1♀ ( IBSP 186392 ) ; Cave Gruta Arcaica (20°17'11''S; 45°47'34''W), 25/I/2008, E. O. Machado & J.P.P. Barbosa col., 1♂ ( IBSP 196169 ) ; Cave Gruta do Angico (20°25'4''S; 45°40'42''W), 25/ VI /2009, R.A. Zampaulo col., 1♀ ( IBSP 196125 ) ; Cave Gruta do Carlinhos (20°24'7''S; 45°40'22''W) 30/III/2013, M.P.A. Oliveira col., 1♀ ( IBSP 181830 ) ; Cave Gruta G-26 (20°22'48''S; 45°37'16''W), 04/ VI /2011, 1♀ ( IBSP 186012 ) ; Cave Gruta Trincheira do Vietnã (20°17'9''S; 45°47'35''W), 25/I/2008, E. O. Machado & J.P.P. Barbosa col., 1♂ ( IBSP 196170 ) ; Cave ICPA _170, 2013, A.P. Bueno et al. col., 1♀ ( IBSP 196128 ) ; Cave ICPA _777 (20°21'59''S; 45°36'27''W), 18/III-6/IV/2013, 1♂ ( IBSP 196132 ) ; Cave ICPA _794 (20°21'36''S; 45°36'37''W) 18/III-6/ IV/2 0 13, 1♂ ( IBSP 196133 ) ; Cave ICPA _811 (20°21'40''S; 45°36'41''W) 18/ III-06/IV/2013, 1♀ ( IBSP 196137 ) ; Cave ICPA _834, 2013, 1♂ 1♀ ( IBSP 196138 ) ; Cave ICPA _837 (20°22'46''S; 45°35'59''W) 01-06/IV/2013, 1♀ ( IBSP 196134 ) ; Cave ICPA _838 (20°22'46''S; 45°35'59''W) 01-06/IV/2013, 2♂ 2♀ ( IBSP 196127 ) ; Cave ICPA _841, 2013 1♂ ( IBSP 196126 ) ; Cave ICPA _841 (20°22'49''S; 45°35'60''W) 01-06/ IV/2013, 1♀ ( IBSP 196131 ) ; Cave ICPA-148 (20°22'22''S; 45°36'31''W) 18/II- 09/III/2 0 13, 1♀ ( IBSP 186511 ; SEM) ; Cave ICPA-152 (20°22'18''S; 45°36'52''W) 29/VII-10/VIII/2013, 1♂ 1♀ ( IBSP 186539 ) ; Cave ICPA-588 (20°22'7''S; 45°36'60''W) 14/I-02/II/2013, 1♀ ( IBSP 186534 ) ; 1♀ ( IBSP 186538 ) ; Cave ICPA-620 (20°22'41''S; 45°36'28''W) 29/I-08/II/2013, 1♂ ( IBSP 186520 ; SEM) ; Cave ICPA-675 (20°22'28''S; 45°36'30''W) 18/II-09/III/ 2013, 1♂ ( IBSP 186512 ; SEM) ; Cave ICPA-692 (20°22'9''S; 45°36'15''W) 18/II-09/III/2013, 1♂ ( IBSP 186513 ) , all collected by A. P. Bueno et al. col., Cave IM _002 (20°18'8''S; 45°47'40''W), 15/V/2013, M.T.M. Souza col., 1♂

(IBSP 186390); Cave IM_011 (20°18'10''S; 45°47'33''W), 06/XI/2013, M. Barcelos et al., 1♀ ( IBSP 184306 ); Cave IM _025 (20°18'6''S; 45°47'26''W), 23/IV/2013, M.T.M. Souza col., 1♀ ( IBSP 186391 ); Cave SM _163 (20°22'26''S; 45°35'13''W), 13/II/2014, Equipe Spelayon col., 1♀ ( IBSP 186389 ); Cave SM _216 (20°21'45''S; 45°35'36''W), 12/II/2014, Equipe Spelayon col., 1♂ ( IBSP 186386 ); Cave SM _246 (20°21'51''S; 45°35'46''W), 20/ II/2014, Equipe Spelayon col., 1♂ ( IBSP 186387 ); Cave SM _257 (20°21'52''S; 45°35'44''W), 20/II/2014, Equipe Spelayon col., 1♂ 1♀ ( IBSP 186385 ; photo); Cave SM _261 (20°22'21''S; 45°35'14''W), 20/II/2014, Equipe Spelayon col., 1♂ ( IBSP 186384 ); Cave SM _290 (20°22'2''S; 45°35'20''W), 20/II/2014, Equipe Spelayon col., 1♂ ( IBSP 186383 ); Cave SPA_012/013 (20°17'58''S; 45°37'4''W) , 27/VIII/2 0 13, F. O. Borges col., 1♀ ( IBSP 186375 ); MIC _091 (20°25'59''S; 45°37'10''W) 9-15/VI /2015 , Equipe Spelayon et al col., 1♀ ( IBSP 196164 ); Piunhi, Cave ICCA-571 (20°20'45''S; 45°50'52''W), 13-21/I/2014, A.P. Bueno et al. col., 1♀ ( IBSP 186416 ); Santa Bárbara, Cave GAND _0033 (20°05'23''S; 43°39'9''W), 10/II- 20/III/2 0 14, Equipe Carste col., 1♀ ( IBSP 186508 ) 1♂ 1♀ ( IBSP 186509 ) 2♀ ( IBSP 186510 ) .

Etymology. The specific name is a noun in apposition that refers to an expression used by people in the Brazilian State of Minas Gerais meaning “astonishment”, due to the unusual grouped eye arrangement and internal morphology of the female genitalia.

Diagnosis. Matta nuusga is distinguished from other Matta species by having a combination of anterior medial eyes together on a common base ( Fig. 23A, C ) in both sexes, the laminar projection, with enlarged base forming a side flap ( Figs 22C , 24C ̄E) in the male palp and diamond piriform dorsal fold of the uterus externus in females ( Fig. 22F ).

Description. Male (holotype, IBSP 186406). Carapace, chelicerae, labium, endites, sternum and abdomen orange. Legs yellowish white ( Fig. 22A ). Total length 1.25. Carapace projected, 0.53 long, 0.42 wide, with rugose surface laterally, dorsally almost smooth ( Fig. 23A ). Sternal surface tenuously reticulate. Clypeus long, oblique, seven times the length of ocular area ( Fig. 23A ). Eye diameters and interdistances: AME vestigial, contiguous ( Fig. 23A, C ). Cheliceral apophysis robust, large and occupying almost the frontal area, with great number of long hairs and translucent median lamina ( Fig. 23A, C ). Leg measurements: I—femur 0.36/ patella 0.13/ tibia 0.31/ metatarsus 0.2/ tarsus 0.23/ total 1.23; II—0.37/ 0.15/ 0.26/ 0.22/ 0.21/ 1.21; III—0.33/ 0.11/ 0.23/ 0.21/ 0.18/ 1.06; IV—0.41/ 0.13/ 0.36/ 0.25/ 0.28/ 1.43. Leg formula 4123. Leg spination: absent, metatarsus narrowed at base ( Fig. 23E ̄F), leg I with a strong spine on an elevated base ( Fig. 23E ̄F). Abdomen ovoid, large sclerotized plate covering dorsal surface ( Fig. 22A ); 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 half-moon 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, and a line of the four epiandrous spigots. Male palp with femur projected medially, with three long setae and small number of projected, salient and globose thin plates ( Fig. 24F ); tibia strongly swollen, oval, rounded posteriorly; cymbium small; bulbus pearshaped, with short and poor elevated conductor, involving partially the base of the embolus long, flattened, lightly sinuous, and very enlarged at apex, with short and acute basal laminar projection, with enlarged base forming a side flap ( Figs 22B ̄C, 24ĀE).

Female (Paratype, IBSP 186406). Coloration pattern as in male ( Fig. 22D ). Total length 1.23. Carapace as in male, 0.52 long, 0.4 wide. Clypeus and sternum as in male. Eyes as in male. Chelicerae with reduced apophysis, shorter than male, with ventral translucent hyaline keel ( Fig. 25B ). Leg measurements: I—femur 0.42/ patella 0.13/ tibia 0.31/ metatarsus 0.21/ tarsus 0.25/ total 1.32; II—0.37/ 0.12/ 0.25/ 0.17/ 0.23/ 1.14; III—0.29/ 0.12/ 0.21/ 0.18/ 0.21/ 1.01; IV—0.43/ 0.14/ 0.39/ 0.28/ 0.23/ 1.47. Leg formula 4123. Leg spination as in male. Pedipalpal tarsus ending in acuminate, smooth pit.

Abdomen with plates as in male ( Fig. 25D ̄E). Vulvae externally with large V-shaped receptacle, visible by transparency ( Fig. 22E ); Ʌ-shaped post genital plate and enlarged copulatory opening ( Fig. 25F ). Internally with enlarged receptaculum and narrow basal area of the copulatory ducts; central process 8-shaped, with one third of the length of the receptaculum ( Fig. 22F ).

Natural history. All specimens of Matta nuusga sp. n. were collected in limestone caves in the karst region of Arcos-Pains and surroundings. Individuals were located on the cave floor below rocks in aphotic zones of the caves. Based in the eye modification and long hairs of trichobothria we hypothesize that this species is a troglobite.

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

Figures

FIGURE 22. Matta nuusga sp. n., male IBSP 186385 (A–C), female IBSP 186385 (D‒F) A habitus, dorsal view B palp, prolateral view C same, retrolateral view D habitus, dorsal view E abdomen, ventral view F vulva, cleared, dorsal view.

FIGURE 23. Matta nuusga sp. n., male IBSP 186512 A carapace, frontal view B chelicerae, frontal view C carapace, ocular area, dorsal view D chelicerae, detail, lateral view E leg I, prolateral view F same, retrolateral view.

FIGURE 24. Matta nuusga sp. n., male palp IBSP 186520 A prolateral view B detail, prolateral view C retrolateral view D detail, retrolateral view E frontal view F palp tibiae, prolateral view (Abbreviations: F, flap).

FIGURE 25. Matta nuusga sp. n., female IBSP 186511 A carapace, frontal view B same, chelicerae, detail, frontal view C same, lateral view D abdomen, lateral view E same, ventral view F same, vulva plate.

FIGURE 30. A Matta nuusga = pentagon white, M. cambito = yellow star; B M. teteia = red star, M. humrrum = pentagon blue, M. pititinha = yellow spangle; C M. zuiuda = close white circle, M. humhum = yellow square.