Turonychus Derkarabetian, Prieto and Giribet, 2021

Derkarabetian, Shahan, Baker, Caitlin M., Hedin, Marshal, Prieto, Carlos E. & Giribet, Gonzalo, 2021, Phylogenomic re-evaluation of Triaenonychoidea (Opiliones: Laniatores), and systematics of Triaenonychidae, including new families, genera and species, Invertebrate Systematics 167 (1), pp. 277-288 : 145

Genus Turonychus Derkarabetian, Prieto and Giribet , gen. nov.

( Fig. 7 B , 9 , 10 )

ZooBank LSID: urn:lsid:zoobank.org:act:A8BBEC1D-7252-4F82-ADF9-7A0816D28080

Type species: Turonychus fadriquei Derkarabetian, Prieto & Giribet , sp. nov., by monotypy.

Diagnosis

This genus can be distinguished from all other Buemarinoidae species based on the number of tarsal segments of leg I: Turonychus has 4+ segments whereas all others have three. Additionally, Turonychus can be distinguished from Buemarinoa by the number of spines on the retrolateral surface of the pedipalp tibia: Turonychus has two spines, whereas Buemarinoa has three ( Fig. 9 B ). The type locality of Turonychus is in the Levantine region of Spain, ~ 300 km south of the Pyrenees Mountains, a region with a broad distribution of Travunioidea with many local cave-obligate species. Turonychus can be diagnosed from Travunioidea based on male genitalia, as noted for the family above ( Fig. 7 B ).

Description

Troglomorphic species with unpigmented and uniformly granulated body ( Fig. 9 A ). Eye mound highly reduced in size, smooth, rising from the anterior margin of the carapace ( Fig. 9 A , 10 A, B ), eyes and retinae completely lacking. Dorsal scutum outline Eta H of Kury and Medrano (2016) ( Fig. 9 A , 10 A ). Sternum thin and elongate ( Fig. 10 C ). Genital operculum wide, bearing small tubercles ( Fig. 10 C ). Pedipalps thin, elongate, lacking pigment, with elongate spines bearing setae ( Fig. 9 B , 10 E, F ). Legs extremely long, thin, lacking pigment. Tarsal formula: 4 – 5,13 – 15,4,4. Penis with ventral plate modified into two elongate articulated lobes each of which have two superior and three inferior spines ( Fig. 7 B ).

Comments

We describe Turonychus as a new genus, as opposed to a second species of Buemarinoa , as it differs from the latter in multiple morphological characters noted above. Other differences may become more apparent with additional specimens of Buemarinoa (e.g. spine-bearing tubercles at lateral margins of scutal segments). Additionally, the divergence between these two genera is likely ancient, as Sardinia began separating from the mainland (now the north-eastern part of the Iberian Peninsula) beginning ~30 MA ( Schettino and Turco 2006).

Etymology

The genus prefix is derived from the demonym for the province of Teruel (‘turolense’) where the type locality is found, and the suffix is derived from Latin onyx and Ancient Greek ó ’ n u j (ónux) meaning ‘claw’, a common suffix applied to many travunioid and triaenonychoid genera. The prefix turol- may be more accurate; however we prefer tur- as it is more euphonious.

Figures

Fig. 7. Morphology of male genitalia. (A) Abaddon despoliator, gen. nov., sp. nov., ventral and ventrolateral views of male paratype (MCZ:IZ:132893_3). (B) Turonychus fadriquei, gen. nov., sp. nov., ventral and lateral views of male holotype.

Fig.9. General morphology of Turonychus fadriquei, gen. nov., sp. nov.: (A) dorsal habitus of female paratype (UPV/EHU Col. Arachnida #5122); (B) retrolateral view of pedipalp of female paratype (UPV/EHU Col. Arachnida #5122). Scale bars: 1 mm; figures at same scale.

Fig. 10. Turonychus fadriquei, gen. nov., sp. nov. Scanning electron micrographs of paratype UPV/EHU Col. Arachnida #5122: (A) dorsum (scale bar: 500 Mm); (B) detail of ocularium (scale bar: 50 Mm); (C) sternal prosomal region (scale bar: 250 Mm); (D) left chelicera, retrolateral view (scale bar: 200 Mm); (E) left palp, retrolateral view (scale bar: 500 Mm); (F) right palp, prolateral view (scale bar: 500 Mm).