Socotracris Desutter-Grandcolas
Creators: name: Desutter-Grandcolas, Laure
name: Felix, Rob P. W. H.
Publisher: name: Zenodo
Year: 2012
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Orthoptera
Haglotettigoniidae
Socotracris

description: Socotracris Desutter-Grandcolas n. gen.
Type species: Socotracris kleukersi n. sp. by monotypy.
Distribution. Known from Socotra (Yemen) only.
Diagnosis. Genus characterized by the shape of the head (face concave, fastigium twice as long as wide, ocelli not distinct, eyes reduced but protruding, maxillary palpi very elongate), its transverse, slightly saddle-shaped pronotum with raised lateral anterior angles, the armature (2 outer and 3 / 4 inner small subapical spurs, strong serrulation over the whole tibia length) and thin shape of its hind tibiae. Males characterized by their FW venation (harp with numerous oblique, parallel veins, mirror not distinct, apical field very reduced; limit between dorsal and lateral fields made by MA), glandular metanotum, tergites without glandular structures, and genitalia (pseudepiphallic sclerite longer than wide, with parallel lateral margins and two small, membranous apical lophi, pseudepiphallic parameres as a concave plate, endophallic sclerite with three distal prongs, endophallic apodeme lamellar). Females characterized by their very small, not overlapping FWs with few veins, the curved ovipositor with a smooth, only slightly widened apex, and the small, ring-shaped copulatory papilla.
Description. Large phalangopsid cricket (Fig. 1). Head. Eyes very small, but protruding (Fig. 2 A), their inner margins with many smaller ommatidia. Ocelli not distinct. Fastigium nearly twice as long as wide, not separated from the vertex by a furrow, but clearly below vertex level (Fig. 2 C). Face concave at the level of the epistemal suture. Maxillary palpi very long and thin, especially joints 3 to 5; joint 3 smaller than joint 4; joint 5 the longest, only slightly widened in apical fourth. Scapes longer than wide. Pronotum. Transverse, hemmed over its whole margin. Dorsal disc raised in distal third, slightly saddle-like (Fig. 2 C); anterior margin concave; distal margin straight (Fig. 2 E). Lateral lobe anterior angles raised. Legs. All long and thin, the tarsomeres more than half the length of the tibiae. TI with a small, inner tympanum. TI and TII with 2 apical spurs each. FIII (Fig. 3 D) with a filiform apical part. TIII with 3 small, outer apical spurs, the median the longest; 3 inner apical spurs, the median the longest, less than half the length of hind basitarsomere; inner ventral apical spur longer than the outer one; 2 outer and 3 / 4 inner subapical spurs located in lower half of tibiae, all small, the inners longer than the outers. TIII serrulated over their whole length, with small but thick spines, located on the raised margins of the tibiae. Terminalia. Cerci very long and thin, longer than the body.
Male: Metanotum glandular, with a wide median pit full of long setae (Fig. 2 F), but tergites not glandular. FWs well developed, but not covering half of the abdomen. Stridulum ressembling that of some Paragryllodes species, with a large harp crossed by many oblique, parallel veins but without a distinct mirror (Fig. 3 B). Additional venation: diagonal bifurcated toward the file; chords 2 and 3 fused near their base; a wide area between MA and CuA, flat, including a short, incomplete MP and a false vein made of a yellow fold; apical field reduced. Limit between lateral and dorsal fields made by MA. Lateral field (Fig. 3 A) narrowed distally; R bifurcated several times in an irregular way, only the distal bifurcations reaching FW lower margin; area between R and MA very wide.
Male genitalia: Pseudepiphallic sclerite (Fig. 4 A–C) longer than wide, its lateral margins almost parallel; median part less sclerotized than the lateral ones; distal margin slightly concave between two membranous lateral lophi bearing small setae; anterior margin greatly concave. Rami longer than pseudepiphallic sclerite and at right angle from it; two distinct contractions in their distal half. Pseudepiphallic parameres having the shape of a short concave plate, directly prolonging the ectophallic apodemes. Ectophallic apodemes long and quite thick, going beyond the anterior margin of pseudepiphallic sclerite; no ectophallic arc proper, but the base of ectophallic fold reinforced by a sclerotization of the epi-ectophallic invagination and connected to ectophallic apodemes; ectophallic fold otherwise membranous, except for a sclerite on its ventral side. Endophallic sclerite with three distal prongs. Endophallic apodeme lamellar; no endophallic crest. Endophallic cavity lacking.
Female: FWs very short and not overlapping (Fig. 3 C); venation reduced on both dorsal and lateral fields (Fig. 3 C). Subgenital plate short; distal margin concave (Fig. 4 J). Ovipositor arcuate; valves apex only slightly widened, without ornamentation (Fig. 4 K).
Female genitalia: Copulatory papilla small and apically rounded (Fig. 4 D–F); sclerotization circular, wider ventrally than dorsally (Fig. 4 F). Spermathecal duct very thin.
Relationships. To our knowledge, the combination of characters present in Socotracris n. gen. has never been observed in Phalangopsidae crickets, and the relationships of this taxon are hard to hypothesize. Within African Phalangopsidae, the venation of male FW, and more specifically the high number of harp veins and the structure of the mirror, resembles that of some Paragryllodes species, such as P. annulicornis Kaltenbach, 1982. Homoeogryllus Guérin-Méneville, 1844 also shows many harp veins, but its FWs are well-developed, most often covering the whole body, and the mirror is wide and crossed by several parallel veins. Socotracris n. gen. clearly differs from these two genera by the structure of male genitalia (Desutter 1985, Desutter-Grandcolas 1998, 1999, Kaltenbach 1982): the pseudepiphallic sclerite is longer than wide (transverse in both Paragryllodes and Homoeogryllus), with small, indistinct lophi (large in both genera) and pseudepiphallic parameres have the shape of a horizontal plate (different in both genera). Socotracris n. gen. resembles however Homoeogryllus by the lack of ectophallic dorsal valves (well-developed in Paragryllodes) and the shape of the long endophallic sclerite, with a 3-prong distal margin (endophallic sclerite modified in Paragryllodes because of the presence of ectophallic dorsal valves): these two characters may also be present in the Indian genera Arachnomimus Saussure, 1897 and Kempiola Uvarov, 1940, which have a different endophallic apodeme (longitudinal crest running on the sclerite, instead of an apical lamella). Of the other phalangopsid crickets present in the Indian Ocean, only Seychellesia Bolivar, 1912 (Gorochov 2006) and Phalangacris, Bolivar, 1895 could resemble Socotracris n. gen. by their pseudepiphallic sclerite and lophi (although their sclerite is shorter than in Socotracris n. gen.), and by the shape of their rami; the other parts of their genitalia and their general morphology are however different. A molecular analysis of phalangopsid relationships at the scale of the Indian Ocean is currently under way.
description: Published as part of Desutter-Grandcolas, Laure & Felix, Rob P. W. H., 2012, Socotracris kleukersi n. gen. n. sp., a new troglobitic cricket from Socotra (Yemen) (Orthoptera: Grylloidea, Phalangopsidae), pp. 57-65 in Zootaxa 3252 on pages 58-59, DOI: 10.5281/zenodo.213251