Updating the taxonomy and distribution of Liparoscelis pallidispina Stål , 1873 ( Orthoptera : Tettigoniidae : Pseudophyllinae )

A detailed complement to the description of the Mexican endemic Pseudophyllinae Liparoscelis pallidispina Stål, 1873 is herein presented, based on several old museum specimens plus recently collected adults. As results, the species diagnosis is updated according to the current taxonomical standards for the order. Moreover, its geographical distribution is clarified and the first precise records of this monotypic genus are given for Michoacán, México and Guerrero States, all of them located at moderately high altitudes on the southern slopes of the Transverse Neovolcanic Belt, above the northeastern reaches of the Balsas Basin. A thorough illustrative complement, which includes a precise map and color photographs of habitus, main morphologically diagnostic structures, habitat and microhabitat.


Introduction
Liparoscelis Stål, 1873 is currently a monotypic genus, with the single species Liparoscelis pallidispina Stål, 1873.It is endemic to Mexico and apparently very rare, to the point that there is only one precise locality recorded: Cuernavaca in Morelos State, by Brunner von Wattenwyl (1895).
Very recently, the present author was fortunate to obtain three adult specimens of L. pallidispina: two males and one female, all in perfect state of preservation.These specimens were accompanied by complete collecting data and high-resolution photographs of their live habitus, habitat and microhabitat.This drove the present author to prepare the present paper, focused on updating the taxonomy and distribution of this seldom found, poorly known and almost neglected member of Pseudophyllinae.

Material and Methods
The present complementary description is based on the freshly preserved specimens, but all available data from supplementary sources was retrieved to prepare the distribution map and the photographic plates.
The specimens were studied, measured and photographed under a Zeiss Stemi 2000-C stereomicroscope, equipped with line scale and grid ocular micrometers, and a Canon PowerShot A620 digital camera.The digital images were processed with Adobe Photoshop CS3 only slightly, i.e., optimization of brightness and contrast parameters, background removal and plate composition.
Specimen labels were laser-printed in Spanish, but transcribed into English here for text coherence.Additional collecting data not included in the labels were directly taken from the field notes of the collector (Rolando Teruel, pers. comm.).Precise coordinates and altitude of each locality were taken in situ with a portable GPS device (Datum WGS84), and later used to construct the distribution map (fig.17) in Mapinfo Professional ver.10.
General terminology follows Aguirre-Segura & Barranco Vega (2015).Taxonomic arrangements were verified using the Orthoptera Species File Online (OSF), version 5.0/5.0 (Cigliano et al., 2018).All meristic counts were given as fractions for left/right sides.Measurements were taken following the standard method for Orthoptera, as modified by Yong (2018), e.g., for structures hidden under others (such as tergites of a shrunk abdomen, a case present in one freshly collected male), the total length corresponds to the sum of all tergites individually measured across translucent tegument in dorsal view.
Abdomen (fig. 7, 12).Long and robust, subcylindrical, tegument coriaceous.Penultimate abdominal tergite much wider than long (ratio = 2.7), with posterior margin widely W-shaped and sloping backwards.Supra-anal plate (fig.12a) wider than long (ratio = 1.8), widely paraboloid and shallowly concave; tegument feebly punctate and with minute setae scattered all over, especially on posterior margin; median-longitudinal sulcus short and shallow.Cerci relatively short (not reaching posterior margin of subgenital plate in dorsal view), cylindrical and digitiform, densely covered by short and rigid setae.Subgenital plate (fig.12c) large, symmetrical and longer than wide (ratio = 1.1); tegument coriaceous to glossy and feebly punctate, with a pair of lateral keels which are slightly convergent backwards; anterior margin straight, lateral margins angulose, posterior margin deeply V-notched, all margins covered by minute setae.Styli relatively long and densely covered all over by minute setae.
Adult female (figs. 8-13, table I).Very similar to male, except as follows.Body larger (48 mm) and more robust.Coloration only with minor differences: pronotum of the same base color as head and with the black stripes interrupted as six separate, symmetrically aligned blotches; legs with infuscate pattern darker and denser; ovipositor yellowish, with basal portion irregularly infuscate and distal half blackish.Tegmina (fig.10a) slightly surpassing the anterior margin of metanotum and widely separate, lanceolate, with coarsely reticulate vein pattern.Head wider than long (ratio = 1.6).Pronotum as wide as long (ratio = 1.0).Legs markedly longer.
Mesotibia with 5:5 / 4:4 spines.Metafemur as long as metatibiae (ratio = 1.0), with 7:0 / 0:6 ventral spines.Metatibia with subapical spines as follows: left leg with 1:5 and 5:3 in its dorsal and ventral surfaces, respectively; right leg with 6:1 and 3:5 in its dorsal and ventral surfaces, respectively.Supra-anal plate (fig.12a) basically paraboloid, wider than long (ratio = 1.6), basal portion with a rounded depression; tegument coriaceous, with minute setae scattered on lateral and posterior margins.Subgenital plate (fig.12c) sub-triangular, wider than long (ratio = 1.5) and tectiform; tegument glossy and feebly, very sparsely punctate; anterior margin shallowly concave, posterior margin paraboloid, basal portion with a triangular deep depression.Ovipositor (fig.11) almost as long as abdomen, broadly knife-shaped and slightly undulate basally; upper edge almost straight and with its apical half minutely serrate; lower edge curved upwards and entirely smooth.Variation.The second male from Queretanillo is actually larger (see table I), but was preserved with its abdomen somewhat shrunk and looks slightly smaller to unaided eye.It also has some minor differences in the leg spination: mesofemur with 3:0 ventral spines.Metafemur with 7:0 ventral spines.Right metatibia with 6:1 and 5:5 subapical spines in dorsal and ventral surfaces, respectively.Distribution (fig.17).From the scarce available data, this species (and the genus Liparoscelis, by extension), is endemic to south-central Mexico.It has been collected only from four moderately high altitude localities (1,200-2,277 m above sea level), all in the southern slopes of the Transverse Volcanic Belt, above the northeastern reaches of the Balsas Basin.Ecological notes.The three specimens from Queretanillo were found together under the loose bark of a single fence post, 1.6 m above the ground, in a moderately cold and humid creek with disturbed oak forest (fig.15).The single specimen from Coatepec-Harinas (a teneral adult female, see fig.14), was found justmolted inside a rotten pine log in the ground, in a very cold and humid, steep slope with mixed pine-oak forest (fig.16).As a curious detail, in both cases the katydids were found resting peacefully along with some individuals of similarly-sized but much less robust scorpions: Centruroides limpidus (Karsch, 1879) at Queretanillo and Vaejovis mexicanus (C.L. Koch, 1836) at Coatepec-Harinas.
No more specimens of L. pallidispina were found in both localities, despite 4-6 hours of intensive daytime search in each.This seems to indicate that the species is almost certainly nocturnal and much easier to find at night, as usual for pseudopyllines.
According the label data of the adult male from El Gavilán, it was captured in mixed oak-pine scrub; the microhabitat was not specified.

General remarks
As stated above, the complementary description of L. pallidispina was based on the fresh specimens from Queretanillo, because these are the best preserved and thus, most reliable for taxonomic purposes.The holotype and the second NHRS female have been dry-pinned for more than 145 years, thus, both have some body proportions altered (especially on abdomen) and the former lost its left foreleg.Nevertheless, it is worth to mention here that these two specimens are otherwise well preserved, thus, are herein depicted too for a best taxonomic comparison.
The few available specimens exhibit some minor differences in coloration, tegument sculpture and morphometric ratios.Nevertheless, all fall well within the range of intraspecific variation (both individual and inter-populations) typical of other Pseudophyllinae (S.Yong, pers. obs.).Moreover, some of these minor discrepancies are clearly attributable to differences in time and method of preservation.

Figure 2 .
Figure 2. Liparoscelis pallidispina, old adult female from NHRS, full-body views: a) dorsal; b) lateral; c) labels.Scale bar in centimeters, with millimeter subdivisions.Modified from photos property of NHRS, available at OSF.

Figure 3 .
Figure 3. Liparoscelis pallidispina, adult male holotype (left) and old adult female from NHRS (right), close-up views of head: a) dorsal; b) lateral; c) frontal.Modified from photos property of NHRS, available at OSF.

Figures
Figures 4-5. 4 Liparoscelis pallidispina, adult male holotype (left) and old adult female from NHRS (right), close-up views of thorax: a) dorsal; b) lateral.Modified from photos property of NHRS, available at OSF. 5 Liparoscelis pallidispina, old adult female from NHRS, close-up view of ovipositor in lateral view.Modified from photos property of NHRS, available at OSF.

Figure 6 .
Figure 6.Liparoscelis pallidispina, adult male holotype (left) and old adult female from NHRS (right), close-up views of abdomen tip: a) dorsal; b) lateral; c) ventral.Modified from photos property of NHRS, available at OSF.

Figure 15 .
Figure 15.Two views of the exact site where Liparoscelis pallidispina was found at Queretanillo: a) habitat in disturbed oak forest; b) microhabitat in fence posts.Photos courtesy Rolando Teruel.

Figure 16 .
Figure 16.Two views of the exact site where Liparoscelis pallidispina was found at Coatepec-Harinas: a) habitat in mixed pine-oak forest; b) microhabitat in rotten pine log.Photos courtesy Rolando Teruel.

Figure 17 .
Figure 17.Geographical distribution of the genus Liparoscelis and its single species L. pallidispina: previous record (red symbol) and new records (yellow symbols, from left to right: Queretanillo, Coatepec-Harinas, El Gavilán and Cuernavaca).Image frame = 900 x 400 km, the three main biogeographical units of this region are represented and the small inset in bottom left shows its location in Mexico.
, granulose, coarsely and sparsely punctate.Fastigium small, conical with tip bilobed.Pronotum densely granulose, with median, anterior and typical sulci deep.Male brachypterous, female micropterous: tegmina coarsely reticulate, in male sub-quadrate, in female spatulate.Hind wings absent.Supra-anal plate paraboloid and with a median depression, longitudinal in male, circular in female.Subgenital plate in male large and widely arrowhead-shaped, with tip deeply emarginate medially and with a pair of lateral keels which are slightly convergent backwards, in female sub-triangular, with tip rounded, without keels and with basal portion with a deep triangular depression.Ovipositor broadly knife-shaped, dorsal edge minutely serrate on distal half.
). Coloration predominantly light to medium brown, usually darker on pronotum and abdomen; head with eyes, fastigium, antennal scapus + pedicel black; pronotum with two black dorsolateral stripes (variably from solid to interrupted); legs irregularly infuscate, with knees deeply infuscate to black; tegmina dark brown to blackish with veins yellow; abdominal tergites with posterior margin conspicuously paler; ovipositor with distal half black.Frons flat, rugose

Table I .
Measurements of three adults of Liparoscelis pallidispina from Queretanillo, Michoacán.Abbreviations: length (L), width (W), depth (H), not applicable (NA).Size large for the tribe (total length 45 mm).General coloration: basically light to medium brown, darker on abdomen.Head with eyes, fastigium and antennal sockets black, clypeus whitish and labrum pale yellowish; antennae with dorsal half of scapus and entire pedicel black.Pronotum medium brown, with two wide, irregular, black dorsolateral stripes, angulose-convergent in dorsal view.Legs with femur and tibia irregularly infuscate, with knees and tip of spines black.Tegmina blackish, with reticulate venation sharply contrasted in vivid yellow.Abdomen medium to moderately dark brown, tergites with posterior margin conspicuously paler.See figures 7, 13a and table I.