Grylloblatta rothi Gurney 1953

Marshall, Christopher J. & Lytle, David A., 2015, Two new species of Grylloblatta Walker, 1914 (Grylloblattodea: Grylloblattidae) from western North America, and a neotype designation for G. rothi Gurney 1953, Zootaxa 3949 (3), pp. 408-418 : 410-412

Grylloblatta rothi Gurney 1953

( Figs. 1 A–F)

Material examined. Neotype male, OSAC #0000583177, “ OR: Deschutes Co., Cultus Mtn. on/near summit 6720’ 10T590843, 4852390; Lytle & Marshall, 21 June 2011 ” with code number “7048” written in pencil on label margin; right metathoracic leg detached, left metathoracic leg missing (removed for sequencing). The UTM coordinates on the label correspond to 43.8190°N, - 121.8703°W. Specimen in ethanol, to be deposited at USNM. Extracted genomic DNA deposited at Oregon State Arthropod Collection, Corvallis, OR, OSAC #00000583177: DNA:01. Thirteen specimens (3 males, 7 females, 3 juveniles), same collection data as neotype, deposited in OSAC ( OSAC _AC_ 2012-12-12 -001). All specimens were collected on snow fields at night near the summit, except a single juvenile found beneath a rock. Numerous carabid beetles and spiders were active on the snowfields as well.

Description: Neotype body length 12.2 mm (measurements taken on ethanol-preserved specimen). Antenna with 24 segments on left and 25 on right [ Gurney (1953): 29 on left, 16 on broken right antenna]. Abdominal sternites finely pubescent, with relatively few larger porect setae distributed across the surface. Abdominal tergites finely pubescent, with several erect setae along posterior margins. Cerci with 9 articulated segments, right cercus length 2.2 mm; first two basal segments appear to be comprised of two fused segments (indicated by two rings of trichobothria, which generally occur at the apex of an articulated segment, and faint vestiges of articulation); cerci shorter than the abdomen proper. Head width 2.4 mm, length 2.2 mm. Pronotum length 2.5 mm, width 2.1 mm. Interocular distance 1.8 mm, eye width 0.5 mm. Left hind femur length 3.3 mm, width 0.8 mm. Left hind tibia length 3.3 mm.

Male supranal plate strongly asymmetrical; left finger-like lobe approaching the longitudinal midline of the abdomen; right finger-like posterior lobe less developed, at an approximate 60° angle. Male gonocoxae ( Fig 1 B,C; gcx-l, gcx-r) asymmetrical, covered in fine setae with a few larger ones basomedially. Gonostyli ( Fig 1 B,C gst-l, gst-r) articulate medially (not basally), appearing ‘hammerhead-like’ when viewed laterally. Right gonocoxa more elongate than left; bearing a distinct dorsal finger that projects medially and opposes the beak-like apex of the primary copulatory sclerite.

Primary copulatory sclerite (main phallic sclerite in Gurney 1953) with dorsolateral lobe about half as long as lateral margin below the dorsal cap ( Fig 1 E, pcs). Secondary accessory sclerite (apical lobe of accessory sclerite of right phallomere in Gurney 1953) ( Fig 1 D,E, sas) rounded and lobe-like. Apex (terminus) of primary male copulatory sclerite expanded along apico-dorsal edge into noticeable flange ( Fig. 1 F, pcs —arrow).

Distribution. Kamp (1973) placed G. ro t h i within an assemblage of species inhabiting the high Cascades of Central Oregon, specifically Broken Top and Belknap Crater. Cultus Mountain is within this area, a region largely defined by the peaks of the Three Sisters. In the original description, Gurney also described an allotype, a single female specimen known from Crater Lake. He united these two specimens (the only specimens in the rothi assemblage known to Gurney) based on their relatively short cerci. Later researchers, including the present authors, expressed doubt that these two specimens were actually conspecific. Kamp, who was likely the last person to view the original type material, and who had in his possession specimens from throughout Oregon, believed the population at Crater Lake to be a distinct species ( Kamp 1973). Our own research into populations in the vicinity of Crater Lake confirm his suspicions and we do not believe Grylloblatta rothi to be distributed this far south of the central Cascades.

Remarks. Gurney (1953) described the holotype male as generally pale ‘antimony yellow’ with a ‘dark yellow ochre’ dorsum. The neotype and other specimens in our possession are consistent with this general yellowishbrown description and to our eyes their overall color approximates yellow ochre. As in Gurney’s original description, G. ro t h i we have examined are generally small for the genus, with alcohol-preserved male specimens ranging from 11.9 to 12.5 mm and females from 14.3 to 15.0 mm in length. The number of antennal segments in adult Grylloblatta is commonly used in identification keys to species, despite that it is a notoriously variable character between, and even within, individuals in a single population. The neotype differs in its antennal segment count from that reported for the left antenna in Gurney’s holotype. However it must be noted that specimens from the same population as the neotype show a range in antennal counts, ranging from 19 to 29 antennal segments and even display intra-individual discrepancies between right and left antenna as great as 10 segments. Thus, we do not feel that the precise number of antennal segments (in either the holotype or neotype) is of great importance for understanding the species.

The male copulatory sclerites were not described in great detail by Gurney (1953) but he does note that the male dorsolateral lobe of the primary copulatory sclerite is about ‘about half as long as lateral margin below the dorsal cap’—a description that is consistent with the dorsolateral lobe of seen in male Grylloblatta from the Cultus Mountain population (dll, Fig. 1 E). Gurney did not mention that the primary male copulatory sclerite is expanded apicodorsally into a flange, a trait that is shared with G. newberryensis . However, this flange is only visible when viewed from a specific angle (notably an anterior facing view, as shown in the illustrations herein ( Fig. 1 F), which was not depicted in Guney’s illustrations of the holotype. Gurney did describe and illustrate the secondary accessory sclerite (referred to as the ‘apical lobe of the accessory sclerite of the right phallomere’) as being rounded and lobe like, consistent with the males from Cultus Mountain ( Fig 1 D,E, sas).

Lastly, the cerci of this species are noticeable short in comparison to many other Grylloblatta species, a trait noted by Gurney in 1953, “The shortness of the cercal segments separates rothi from all other species except possibly barberi , and the character is so distinctive that the association of sexes [holotype and allotype] is believed correct.” However, both species described below share this trait as well as several other traits found in G. rothi and a more detailed, comparative study of the species allied to G. ro t h i, is currently being conducted by the authors. Female cerci are only slightly longer than the ovipositor. The ovipositor is ventrally covered in short setae, which is denser at the base and apex than they are medially. The dorsal valvula is slightly longer than the ventral valvula ( Fig 1 A).

Paratypes (including the allotype) of a species have no special significance in the determination of a neotype. Still, they may provide information to help clarify the species concept being employed by the original author. Unfortunately, in this particular case, the species concept was based on only two specimens (the holotype and allotype) that Gurney treated as conspecific based solely on the short cerci. We searched for the allotype along with the holotype unsuccessfully and we presume they were lost at the same time.

Figures

FIGURE 1. Grylloblatta rothi. A, female, lateral view of ovipositor and cercus showing the dorsal valvula (dv); B, male, lateral view of right gonocoxa (gcx-r) and right gonostylus (gst-r); C, male, lateral view of left gonocoxa (gcx-l) and left gonostylus (gst-l); D, male, anterodorsal view showing details of secondary accessory sclerite (sas); E, male, anterodorsal view of primary copulatory sclerite (pcs) and secondary accessory sclerite, with dorsolateral lobe of main phallic sclerite visible (dll); F, male, anterior view of primary copulatory sclerite, showing expanded apical-dorsal flange (arrow).