Phantasca valgius ( Westwood, 1859 )

Hennemann, Frank H., Conle, Oskar V., Bellanger, Yannick, Lelong, Philippe & Jourdan, Toni, 2018, Studies on neotropical Phasmatodea XVII: Revision of Phantasca Redtenbacher, 1906, with the descriptions of six new species (Phasmatodea: Diapheromeridae: Diapheromerinae), European Journal of Taxonomy 435, pp. 1-62 : 56-59

Phantasca valgius ( Westwood, 1859)

Figs 120–124

Phasma valgius Westwood, 1859: 126 , pl. 10, fig. 3 (♂).

Cladoxerus valgius – Kirby 1904: 358.

Phantasca valgia – Redtenbacher 1906: 111. — Zompro 2001: 223. — Otte & Brock 2005: 264. — Brock, Marshall, Beccaloni & Harman 2016: 201.

Material examined

Holotype

BRAZIL: ♂, “Type; valgius Westw. ; Phasma valgius Westw. ; BMNH(E) #844548 ” (NHMUK).

Diagnosis

Males (the only sex known) of this species are well characterised and readily distinguished from all other species by the distinctively dark longitudinal veins of the tegmina and costal region of the alae. Since the unique holotype of P. valgius ( Westwood, 1859) is badly mutilated, discoloured and has most of the abdomen distorted and shrunken due to former preservation in spirits, any further distinguishing and characterizing features are impossible to define. The straight cerci, which clearly project beyond the apex of the abdomen, resemble those of P. nigrolineata sp. nov. and P. puppeia ( Westwood, 1859) , while the shape of the very small poculum resembles those of P. quadrilobata ( Chopard, 1911) .

Description

Male ( Fig. 120 )

BODY. Small for the genus (body length ca 50.0 mm, Table 13); form moderately slender.

COLOUR. Pale buff. Tegmina and costal region of alae pale greyish buff, with all longitudinal veins dark brown; tegmina, with a small elongate-oval, sub-basal brown spot near anterior margin. Anal region of alae subhyaline, with a slight orange wash. Antennae of same colour as body but tending to become darker brown towards the apex and with some broad but faint darker annulations.

HEAD. Flattened ( Fig. 121 ), some 1.3× as long as wide and broadest at the eyes; vertex slightly raised posteriorly and with a transverse row of minute blunt tubercles near posterior margin ( Fig. 122 ). Eyes oval on outline, strongly projecting and their length contained only about 1.1× in that of cheeks.Antennae less filiform than in other members of the genus and at least reaching to abdominal segment IV (apices broken in the unique holotype). Scapus rectangular and about 1.2× as long as wide. Antennomere III slender and about 1.3× as long as pedicellus.

THORAX. Pronotum slightly narrower than head, rectangular and some 1.2× as long as wide, with both the longitudinal median and transverse sulcus weakly defined. Mesothorax elongate, some 2.4× as long as head and prothorax combined. Mesonotum finely and sparsely granulose,, with a fine longitudinal median carina. Tegmina elongate-oval, constricted at the base and projecting slightly beyond posterior margin of metanotum; fully covering base of alae. Alae reaching ⅓ along abdominal segment V.

ABDOMEN. Median segment fairly short for the genus and only about 1.3× as long as metanotum. Abdominal segments II–VI very elongate and on average about 6× as long as wide; VII shorter than all preceding. VIII gradually thickened and fully separated from sternum VIII. IX longer than VIII, constricted medially, with the lateral margins roundly deflexed in posterior half and almost touching each other ventrally. Anal segment considerably longer than wide, slightly gradually narrowed towards the posterior and gently tectiform ( Fig. 123 ); the posterior margin, with a deep and narrow, roundly triangular notch, the outer angles projecting and obtusely triangular, with several minute denticles ventrally ( Fig. 124 ). Cerci straight, obtuse, compressed basally, about ⅔ the length of anal segment and decidedly projecting beyond its extremity. Vomer distinct, elongate, with a longitudinal median furrow and a single moderately pointed apical hook ( Fig. 124 ). Poculum small, cup-shaped, with the posterior portion gradually flattened and the posterior margin obtusely angulate; reaching about halfway along tergum IX ( Fig. 123 ).

LEGS. Moderately long and slender, mesofemora longer than mesothorax and hind legs distinctly projecting beyond apex of abdomen. Unicoloured except for a slightly darker apex of the femora. Meso- and metabasitarsus moderately elongate and sub-equal to combined length of remaining tarsomeres.

Remarks

The unique male holotype is badly damaged and incomplete ( Fig. 120 ). It lacks both front and mid legs, the right hind leg, all tarsi as well as parts of the antennae and most of the anal fan of the alae. The specimen is also much deformed and discoloured due to a former preservation in spirits, the abdomen being strongly bent. This makes exact measuring of the specimen impossible. Female and egg unknown.

Distribution

Not known. Possibly from northeast Brazil.

Figures

Figs 120–124. Phantasca valgius (Westwood, 1859). Holotype, ♂. 120. Habitus, dorsal view. 121. Head and pronotum, lateral view. 122. Head and pronotum, dorsal view. 123. Apex of abdomen, lateral view. 124. Anal segment, ventral view.