Kryptochroma gigas Machado & Viecelli, 2021

Machado, Miguel, Viecelli, Rafaela, Guzati, Catherine, Grismado, Cristian J. & Teixeira, Renato A., 2021, Kryptochroma: a new genus of bark-dwelling crab spiders (Araneae, Thomisidae), European Journal of Taxonomy 778, pp. 26-70 : 32-34

Kryptochroma gigas Machado & Viecelli gen. et sp. nov.

urn:lsid:zoobank.org:act:6DC79758-A014-4D6F-960B-4C63ACB17982

Figs 3 , 9 , 21A

Diagnosis

The female of Kryptochroma gigas gen. et sp. nov. resembles those of K. quadrata sp. nov. and K. pentacantha by its large body size, which is significantly larger than in the other species here described. Kryptochroma gigas gen. et sp. nov. can be distinguished by the elevated and short opisthosoma and by the heart-shaped epigynal plate with a short and stout projection over a wide median septum, which divides the median field in two longitudinal gutters reaching the copulatory openings ( Figs 3C–F , 21A ).

Etymology

The epithet is a Latin feminine noun that means giant, referring to the bigger size of this species compared to other species of the genus.

Material examined

Holotype BRAZIL • ♀; Minas Gerais, Simonésia, Estação Biológica da Mata do Sossego ; 20°04′25″ S, 42°04′13″ W; 28–30 Nov. 2010; M.T.T. Santos leg.; UFMG 4734 .

Additional material

None.

Description

Female (holotype, UFMG 4734)

PROSOMA. Anterior eye row very recurved and posterior slightly procurved; prosoma dark yellow with large lateral black taints, median region and posterior slope yellow, contoured by black lines ( Fig. 3A– B ). Chelicerae dark yellow with black stains, endites and labium black, sternum black with a median yellow taint.

LEGS. Femora I and II dorsally enlarged and with many setiferous tubercles, femora III and IV bicolor, half black, half yellow.

OPISTHOSOMA. Predominantly dark-yellow, black on the back of the abdominal projections and on the sides, rough surfaced and slightly concave on the anterior border ( Fig. 3A–B ).

MEASUREMENTS. Eye diameters and eye interdistances:AME 0.09,ALE 0.14, PME 0.12, PLE 0.12, AME– AME 0.08, AME–ALE 0.12, PME–PME 0.24, PME–PLE 0.06, MOQ length 0.43, MOQ width 0.48; leg formula: 1-2-4-3: leg I – femur 4.66/ patella 2.59/ tibiae 3.10/ metatarsus 2.17/ tarsus 1.29/ total 13.81; II – 3.83/ 2.07/ 2.84/ 1.86/ 1.29/ 11.89; III – 2.07/ 1.29/ 1.86/ 1.19/ 0.82/ 7.23; IV – 2.59/ 1.19/ 1.86/ 1.29/ 0.82/ 7.75. Total body length 9.62; prosoma 4.40 length, 4.04 width; opisthosoma

length 4.62; clypeus 0.37 height; sternum 1.45 length, 1.20 width; endites 0.69 length, 0.40 width; labium 0.48 length, 0.53 width.

Male

Unknown.

Distribution

Central Brazil (Minas Gerais) ( Fig. 9 ).

Figures

Fig. 3. Female of Kryptochroma gigas Machado & Viecelli gen. et sp. nov. Holotype (UFMG 4734). A. Habitus, dorsal view (arrows indicate the pair of circular taints on the posterior slope of the prosoma). B. Front. C, E. Epigynal plate, ventral view. D, F. Spermathecae, dorsal view.

Fig. 9. Distribution records of species of Kryptochroma Machado gen. nov.

Fig. 21. Illustrations of epigynum in ventral and dorsal view. A. Kryptochroma gigas Machado & Viecelli gen. et sp. nov., holotype (UFMG 4734). B. K. hilaris Machado & Teixeira gen. et sp. nov., holotype (MPEG 13322). C. K. parahybana (Mello-Leitão, 1929) gen. et comb. nov. (MPEG 30339).