Boreolimnus incisurus (DeLong) Kits, 2024

Kits, Joel H., 2024, Boreolimnus, a new leafhopper genus from northern North America, with a review of Cribrus Oman (Hemiptera, Cicadellidae, Deltocephalinae), ZooKeys 1217, pp. 273-290 : 273-290

Boreolimnus incisurus (DeLong) comb. nov.

Figs 2–14 , 15–24

Deltocephalus (Laevicephalus) concinnus var. incisurus DeLong, 1926: 77

Laevicephalus concinnus var. incisurus (DeLong) . Comb. DeLong and Caldwell 1937.

Laevicephalus incisurus ( DeLong, 1926) . Rev. stat. Beamer 1938.

= Latalus hultus Beirne, 1954: 123 . Syn. Ross and Hamilton 1972.

= Cribrus micmac Hamilton in Hamilton and Langor 1987: 669. New synonym.

Description.

Males 3.1–3.4 mm. Females 3.2–3.6 mm.

Colour mostly pale straw to light yellow, with two longitudinal stripes on crown and four longitudinal stripes on pronotum in a deeper yellow colour usually apparent. Palest specimens with dark colour restricted to basal tergites and spots at bases of leg macrosetae. Darker specimens may have light to dark brown markings medially on frontoclypeus (interrupted laterally by pale horizontal lines), in antennal pits, on anepisternum, medially on abdominal tergites, on base of sternite II and laterally on all sternites, and on pygofer. Fore wing milky white with brown infuscation around border of some cells.

Male pygofer process short, originating on postero-ventral margin and extending slightly dorsally. Process typically with two small teeth on ventral margin. Subgenital plates bearing a single row of approximately eight macrosetae laterally. Style with lateral lobe of apophysis quadrately rounded, medial lobe of apophysis sickle-shaped, with four or five widely spaced, rounded teeth ventrally. Aedeagus in lateral view dorsoventrally flattened, strongly curved anterodorsally, extending slightly dorsally of atrium. Atrium in posterior view with deep and broad dorsal excavation; shaft in posterior view broad, narrowing preapically, with a single pair of lateral processes just before apex, terminating in a round plate above gonopore.

Female sternite VII rectangular, posterior margin with slight, rounded projections medially and laterally and gently convex in between, medial projection with a small emargination surrounded by a dark area (Fig. 12 ). Gonoplac mostly dark. Base of first valvula in ventral view truncate (Fig. 11 ).

Material examined.

Holotype of Deltocephalus incisurus DeLong. USA • ♀; Wisconsin, Ladysmith ; 9 Aug. 1916; D. M. DeLong leg.; OSUC, OSUC 870278 .

Holotype of Latalus hultus Beirne. Canada • ♂; Manitoba, Birch River ; 13 Aug. 1930; R. H. Handford leg.; CNC, CNC 1197446 .

Holotype of Cribrus micmac Hamilton. Canada • ♀; Nova Scotia, Cape Breton Highlands National Park, Paquet’s Lake ; 27 Aug. 1983; M. Sharkey leg.; CNC, CNC # HEM 403381 .

Other material.

Canada – Alberta • 1 ♂; Beaverlodge ; 1 Aug. 1961; A. R. Brooks leg.; CNC • 1 ♀; Grande Prairie ; 25 Jul. 1961; A. R. Brooks leg.; CNC • 1 ♂; High Prairie ; 16 Jul. 1961; A. R. Brooks leg.; CNC • 20 ♂, 12 ♀, 1 (no abdomen); same collection data as previous; 17 Jul. 1961; CNC • 18 ♂, 16 ♀, 2 (intersex); same collection data as previous; 22 Jul. 1961; CNC • 1 ♂; same collection data as previous; 25 Jul. 1961; CNC • 1 ♀; same collection data as previous; 26 Jul. 1961; CNC • 3 ♂, 1 ♀; Peace River ; 12 Jul. 1961; A. R. Brooks leg.; CNC • 1 ♂, 7 ♀, 1 (intersex); Valleyview ; 10 Aug. 1961; A. R. Brooks leg; CNC . – New Brunswick • 1; Kouchibouguac National Park ; 16 Aug. 1977; S. J. Miller leg.; CNC . – Ontario • 1 ♀; 10 mi E Nipigon ; 12 Aug. 1975; K. G. A. Hamilton leg.; CNC • 1 ♀; 4 mi S Beardmore ; 12 Aug. 1975; K. G. A. Hamilton leg.; from Calamagrostis canadensis ; CNC • 28 (unmounted specimens in a capsule); Sault Sainte Marie ; 10 Aug. 1975; K. G. A. Hamilton leg.; from Carex sp. ; CNC . – Saskatchewan • 4 ♀; Candle Lake ; 19 Aug. 1959; A. & J. Brooks leg.; CNC . – Manitoba • 1 ♀; The Pas ; 30 Aug. 1959; A. & J. Brooks leg.; CNC .

Remarks.

The holotype of Deltocephalus incisurus (Figs 15–18 ) was not previously labelled as such in the OSUC collection. The red “ paratype ” label and blue “ incisurus ” label were both probably added by later workers. However, it seems clear this is the holotype, as it matches the locality data, description, and illustrations in DeLong (1926). This specimen is also presumably one of the two syntypes of Deltocephalus concinnus Sanders & DeLong , based on the labels which match the data in the original description and the fact that no other potential syntypes could be located in DeLong’s collection (L. Musetti pers. comm. 2022). As I am designating the other syntype as lectotype of D. concinnus (see below), this specimen becomes a paralectotype of the latter species.

The holotype of Latalus hultus (Figs 19–21 ) has been dissected, and matches other males of this species. The original description ( Beirne 1954 a) did not include collection details for the holotype; these were provided in an erratum ( Beirne 1954 b). The latter also mentions a paratype which could not be located in the CNC; its whereabouts are unknown.

The holotype of Cribrus micmac (Figs 22–24 ) has the fore wings reaching about the middle of the genital segment. The hind wing length is difficult to determine precisely as the wings are greasy and stuck together, but they appear to be about as long as the fore wings. In all other examined females, both wings exceed the apex of the genital segment although there is some variation in how far they exceed the apex. The holotype appears to have been parasitized, with a dark mass resembling a dryinid larval sac projecting between the first and second thoracic segments; this could have caused abnormal development of the wings. The seventh sternite also has a shallower medial emargination compared to other females, but again this may represent abnormal development due to parasitization. Otherwise, the holotype matches other examined females in structure and colour, and the small COI fragment available for the specimen (GenBank accession PP 719690, 137 bp) is 100 % identical to the sequence from B. incisurus included in the phylogenetic analysis.

Females of this species can be separated from Cribrus and other Nearctic Paralimnini with longitudinal stripes on the head and pronotum based on the distinctly infuscated cell borders of the fore wing, reduction of the outer anteapical cell, sternite VII with slightly projecting posterior corners and a small darkened emargination medially, and dark gonoplacs.

Distribution.

Recorded from Alberta to Nova Scotia, south to Wisconsin (Fig. 25 ). Locations largely fall within the southern boreal forest or transition zones.

Host plants.

Associated with graminoids in northern wetlands, although the specific host is unclear. The type specimen was collected from “ grasses on the margin of a tamarack bog ” ( DeLong 1926). Beamer’s collection from Cowan, MB was probably collected from grasses along the margin of a lake (based on Beamer’s collection notes for this locality, as quoted by Whitcomb and Hicks 1988: 323). One specimen from near Beardmore, ON was collected from Calamagrostis canadensis , while a large series from Sault Ste. Marie, ON was collected from Carex sp. All three Ontario localities were wetlands with Calamagrostis canadensis as a dominant species (K. G. A. Hamilton field notes, unpublished) and this common wetland grass is a potential candidate for the host plant, but further fieldwork is needed.

Figures

Figure 25. Map of localities for Boreolimnus incisurus (black dots) and Cribrus concinnus (white dots). The half-filled dot is Ladysmith, Wisconsin, type locality for both species and the only known co-occurrence.

Figures 2–14. Boreolimnus incisurus 2 dorsal habitus 3 lateral habitus 4 abdomen ventral, female 5 face 6 male pygofer, dorsal 7 male pygofer, lateral 8 male subgenital plate, styles, connective, dorsal 9 aedeagus, caudal 10 aedeagus, lateral 11 female genital capsule, ventral 12 female sternite VII, ventral 13 first valvifer, lateral, with enlargement 14 second valvifers, lateral, with enlargement.

Figures 15–24. Boreolimnus incisurus and synonyms, primary types 15–18 Deltocephalus concinnus var. incisurus DeLong, holotype 15 dorsal habitus 16 lateral habitus 17 abdomen, ventral 18 labels 19–21 Latalus hultus Beirne, holotype 19 lateral habitus 20 labels 21 dorsal habitus 22–24 Cribrus micmac Hamilton, holotype 22 lateral habitus 23 labels 24 dorsal habitus.