Errastunus sobrinus (DeLong & Sleesman)

Kits, Joel H., 2023, The genus Errastunus in the Nearctic region (Hemiptera, Cicadellidae, Deltocephalinae), ZooKeys 1178, pp. 143-164 : 143

Errastunus sobrinus (DeLong & Sleesman)

Figs 1G, H ; 3 , 5

Latalus ocellaris var. sobrinus DeLong & Sleesman, 1929: 100. Type locality: Slave Lake, AB, Canada.

Deltocephalus sobrinus (DeLong & Sleesman) - Walley 1932 (revised status, comb. nov.).

Errastunus sobrinus (DeLong & Sleesman) - Oman 1949 (comb. nov.).

Errastunus ocellaris = Errastunus ocellaris ( Fallén) - Beirne 1956 (syn. nov.).

Latalus sobrinus (DeLong & Sleesman) - Hamilton 1983 (restored status and comb.).

Latalus (Adarrus) sobrinus (DeLong & Sleesman) - Hamilton 1997 (comb. nov.).

Type material.

This species was described from six syntypes from Alberta and an unknown number of syntypes from New York, all females. I was only able to locate two of these, one (labelled as “holotype”) in OSUC and one (labelled as “paratype”) in INHS. There are three specimens in the USNM collected between 1904-1908 in New York; DeLong and Sleesman cite other specimens from USNM in their paper which suggests they could have seen these, but they did not label the specimens or cite specific details so it is not clear if these are syntypes or not.

In order to clarify the application of the name, the specimen in OSUC (OSUC 169881) is here designated lectotype. The labels on this specimen (individual labels separated by /) read: "Slave L., Alta., Aug. 15, 1924, O. Bryant / Grizzly Mt., 3000 ft. / Holotype [red label, handwritten] / Latalus ocellaris var Latalus ocellaris sobrinus DeL+S / HOLOTYPE, Errastunus sobrinus [red label] / D.M.DeLong Collection / Errastunus sobrinus (DeL.+S.)".

The specimen in INHS (INHS Insect Collection 679931), collected at Slave Lake on Aug 14, and any other former syntypes thus become paralectotypes.

Other material examined.

283 specimens (see Supplementary material)

Distribution.

Endemic to the Nearctic region, where it has a boreo-montane distribution. Occurs across most of Canada, from Labrador and Nova Scotia in the east to Alaska and British Columbia in the west, and south in the Rocky Mountains to Colorado. Although this species was recorded from Yukon by Hamilton (1997), and likely occurs there based on occurrence in Alaska and British Columbia, all examined Errastunus from that territory were E. ocellaris . In the east, the southernmost occurrences appear to be associated with higher elevations, with records from the Laurentian, Chic-Choc, Adirondack and White Mountains and the Cape Breton highlands.

Host plants.

None of the examined specimens had specific host plants recorded. Unpublished collecting notes from K.G.A. Hamilton suggest this species is associated with grasses in wooded habitats.

Remarks.

The combination of morphological, molecular, and distribution data strongly supports the validity of E. sobrinus as a distinct species. Morphological differentiation is moderate, but comparable in degree to that found between species in other genera of Paralimnini . The consistent difference in pygofer shape, along with weaker differences in other male genitalic characters, female characters, and external colour all support this interpretation, while the degree of divergence observed between the two clusters of COI sequences is higher than that seen in many morphologically distinct leafhopper species (unpublished data). The generally distinct distributions, with some overlap, also support this variation as specific rather than random variation within a species or geographic differentiation.

The occurrence of some specimens that morphologically appear to belong to E. sobrinus but have COI sequences falling in the E. ocellaris cluster suggests there has been historic introgression between these species. There is no indication that these specimens are first generation hybrids, as morphologically they appear typical of E. sobrinus . All of these specimens were collected within the range of E. sobrinus , and outside the known current range of E. ocellaris . The sequences of these apparent introgressed individuals fall within the cluster of sequences that includes northwestern North American specimens, suggesting this population is the source of these introgressed haplotypes. The most likely scenario appears to be historic introgression between these northwestern E. ocellaris and E. sobrinus in an area of overlap, with some haplotypes being retained within populations of E. sobrinus .

Figures

Figure 1. Errastunus dorsal habitus A-F Errastunus ocellaris A CNC 1317086 (Chatterton, ON) B CNC 1317151 (Igls, Austria, 900 m) C CNC 1317160 (Oxford, England) D CNC 1317521 (Obergurgl, Austria, 1950 m) E CNC 1317524 (Obergurgl, Austria, 1950 m) F CNC 1615789 (Richardson Mtns, YT, note the extended abdomen is an artifact of preservation) G, H Errastunus sobrinus G CNC # HEM 403281 (Parc de la Gaspesie, QC) H CNC 1317427 (Elkwater Park, AB).

Figure 3. Errastunus sobrinus, male genitalia A-C pygofer, lateral D-F aedeagus, lateral G-I connective and styles, dorsal A, D, G CNC 1317444 (Atlin, BC) B, E, H CNC 1317472 (Waskaganish, QC) C, F, I CNC 1317518 (Waterton Lakes, AB).

Figure 5. Errastunus sobrinus, female genitalia A genital capsule, ventral B first valvula C second valvula D, E sternite 7, ventral A-D CNC 1317465 (Waskaganish, QC) E CNC 1317360 (La Plata Co., CO) F CNC 1317260 (Whitefox, SK) G CNC 1317270 (Rycroft, AB).