Platycynorta depressa (Sorensen, 1932)

Kury, Adriano B. & Medrano, Miguel, 2023, Once upon a time in America: recognition of the species of Libitioides from USA, with comments on other American Cosmetidae (Opiliones, Laniatores), European Journal of Taxonomy 875 (1), pp. 101-141 : 106-109

[7] The striped Texan morph ( Platycynorta depressa )

Sørensen (in Henriksen 1932) described the new species Cynorta depressa Sørensen, 1932 from “America centralis” based on males and females in the Dresden Museum. The arachnid collection in Dresden has been destroyed during World War II, but a subsample survived in ZMUC, which has been examined by ABK ( Fig. 4 ). Henriksen (the editor of Sørensen’s notes posthumously published) placed this species in the subgenus Cynorta , into which he synonymized a great number of generic nomina by Roewer, including Libitioides . He commented: “This species is nearly [sic] related to C. ornata Wood , described above, and is thus to be referred to the genus Libitioides in the Roewerian system in spite of the different armature of the third and fourth abdominal somites.”

Mello-Leitão (1933) made this Cynorta depressa the type of his new genus Platycynorta ( Fig. 2c ). The rationale for the separation of both genera was given as: “Area III tuberculis rotundis areae primae similibus munita” [ Platycynorta ] X “Area III processis conicis duobus armata” [ Libitioides ].

Roewer (1947: 8) described Platycynorta secunda from Cuba. Our colleague Abel Pérez-González kindly shared his images of the holotype, and to our astonishment, we could not find any difference with Sørensen’s species C. albolineata from USA. We do not know if under more thorough examination this species proves different from L. albolineata (or even if the locality was mislabeled), therefore we simply associate this species with the Cuban Vonones modestus and make the transfer to Libitioides leaving it otherwise undisturbed.

Roewer (1952: 42) described the new species Platycynorta transversalis Roewer, 1952 from Seagoville near Dallas, Texas. Roewer’s illustration is surprisingly faithful (showing the sinuous omega-stripe) and his text clearly mentions the typical granulated retrolateral patch on femur IV of male. Cokendolpher & Jones (1991: 86) commented about the unsatisfactory state of the taxonomy of American cosmetids and synonymized Platycynorta transversalis with Vonones sayi .

Finally, Roewer (1957: 89) described yet another Platycynorta , P. clavifemur Roewer, 1957 from Peru. It does not have anything to do with any of the species treated here and is referred below to the genus Ambatoiella Mello-Leitão, 1943 , to which we herein give an extended diagnosis.

Figures

Fig. 4. Libitioides sayi (Simon, 1879), morph C, syntype, ♂ (ZMUC). a. Habitus, dorsal view. b. Same, sinistrolateral view. c. Same, ventral view. d. Same, detail of carapace, dorsal view. e. Labels.

Fig. 2.Libitioides spp. from USA, in vivo. a. L. ornata (Say, 1821) (morph A), ♂ and ♀, Florida, Orange, Orlando Wetlands Park (©Mary Keim). b. L. sayi (Simon, 1879) (morph B, “clean”), ♂, Texas, Sherman Co. (©Kate Farkas). c. L. sayi (morph C, “depressa”), ♂, Texas, Kleberg Co., Padre Island National Seashore (©Meghan Cassidy). d. L. albolineata (Sørensen, 1884) (typical morph D), ♂, Georgia, Fulton Co. (©E. Christina Butler). Photos are somewhat cropped.All images used here under written permission.