Filicicoris, Anna Namyatova & Gerasimos Cassis, 2016

Anna Namyatova & Gerasimos Cassis, 2016, A remarkable new genus and six new species of fern-inhabiting plant bugs endemic to the Society Islands (Insecta: Heteroptera: Miridae: Mirinae: Filicicoris gen. nov.), Insect Systematics & Evolution 47, pp. 285-312 : 287-293

Filicicoris gen. nov.

Etymology

The genus is named for its affiliation with ferns, from the Latin, ‘ filix ’, and the suffix ‘ coris ’, from the Latin, meaning bug. The gender is masculine.

Type species

Filicicoris meyeri Namyatova and Cassis , by original designation.

Diagnosis

Filicicoris is recognized by the following characters: macropterous; body straight, not declivous, smooth, impunctate; body length 3–5 mm; body covered with simple short pale and sometimes dark setae, head transverse ( Fig. 2 A, D); wings translucent; posterior margin of head carinate; eye not pedunculate or protruding laterally, contiguous with pronotum ( Fig. 2 A, D); in lateral view head shorter than high, distance from eye to inferior margin of head subequal to half of eye height ( Fig. 2 B); antennal segment I cylindrical ( Fig. 1 ), not widened, longer than half of head width, usually subequal to or longer than head width; antennal segment II narrow and cylindrical; collar narrow; labium slightly surpassing posterior margin of metasternum; pronotum not constrict- ed behind calli ( Fig. 2 A, D); lateral margin of pronotum rounded, not angulate or carinate; calli shallow, scutellum flat, shorter than claval commissure; R+M reaching cuneus; cuneus twice as long as wide; femora slender, not modified; tarsal segment I shorter than segment II, segments II and III subequal in length ( Fig. 2 J); right paramere digitiform with small apical hook ( Figs. 3 B, E, I, L, O, 4C); left paramere L-shaped ( Figs. 3 C, F, J, M, P, 4D); vesica bearing 3–6 lobes, with small sclerotized spicules, but without long spicules ( Figs. 3 G, 4A); female posterior wall with interramal lobes, without dorsal or lateral lobes or sigmoid process ( Fig. 5 B, D, F, H, J).

Species Length Width Body Cun-Clyp Pronotum AntSeg AntSeg Head Pronotum InterOcDi F. huahine ♂ (N = 5) Mean 3.28 2.38 0.58 0.66 1.75 0.72 1.01 0.36 SD 0.07 0.04 0.03 0.03 0.11 0.00 0.04 0.01 Range 0.17 0.11 0.07 0.06 0.24 0.01 0.10 0.02 Min 3.22 2.33 0.53 0.63 1.67 0.72 0.95 0.35 Max 3.39 2.44 0.60 0.69 1.91 0.73 1.05 0.37 ♀ (N = 5) Mean 3.71 2.69 0.64 0.57 1.61 0.76 1.14 0.36 SD 0.08 0.08 0.03 0.04 0.10 0.01 0.02 0.03 Range 0.19 0.23 0.06 0.10 0.25 0.03 0.04 0.07 Min 3.63 2.56 0.60 0.52 1.54 0.74 1.12 0.33 Max 3.82 2.79 0.67 0.62 1.79 0.77 1.16 0.40 F. mayeri ♂ (N = 5) Mean 3.31 2.34 0.64 0.39 1.26 0.67 1.03 0.34 SD 0.12 0.09 0.05 0.24 0.10 0.02 0.03 0.01 Range 0.34 0.25 0.15 0.57 0.25 0.04 0.09 0.03 Min 3.14 2.19 0.57 0.00 1.14 0.65 0.99 0.33 Max 3.48 2.44 0.72 0.57 1.39 0.69 1.08 0.36 ♀ (N = 5) Mean 3.58 2.50 0.69 0.53 1.18 0.71 1.10 0.36 SD 0.09 0.05 0.01 0.04 0.08 0.01 0.02 0.02 Range 0.24 0.14 0.01 0.11 0.20 0.03 0.05 0.05 Min 3.48 2.44 0.68 0.46 1.10 0.69 1.08 0.35 Max 3.72 2.58 0.69 0.57 1.30 0.72 1.13 0.41 F. rubramaculus ♂ (N = 5) Mean 3.90 2.79 0.55 0.73 1.88 0.77 1.05 0.35 SD 0.09 0.07 0.02 0.06 0.11 0.01 0.04 0.02 Range 0.25 0.18 0.06 0.17 0.29 0.03 0.10 0.04 Min 3.77 2.72 0.52 0.64 1.73 0.76 1.02 0.33 Max 4.02 2.90 0.57 0.81 2.02 0.79 1.11 0.37 ♀ (N = 2) N = 1 4.27 3.07 0.30 0.78 1.86 0.81 1.17 0.37 N = 2 4.24 3.21 0.29 0.77 1.94 0.81 1.27 0.36 F. tatarnici ♂ (N = 1) N = 1 4.18 2.90 0.70 0.85 2.15 0.79 1.17 0.37 F. viridis ♂ (N = 5) Mean 4.58 3.27 0.72 0.91 2.11 0.81 1.23 0.40 SD 0.33 0.22 0.05 0.07 0.09 0.03 0.15 0.03 Range 0.77 0.49 0.12 0.17 0.23 0.07 0.34 0.07 Min 4.25 3.04 0.65 0.82 2.04 0.76 1.09 0.37 Max 5.02 3.53 0.77 0.99 2.27 0.84 1.43 0.43 ♀ (N = 5) Mean 4.73 3.34 0.76 0.86 1.99 0.86 1.27 0.42 SD 0.34 0.24 0.04 0.06 0.10 0.09 0.11 0.02 Range 0.76 0.57 0.11 0.15 0.25 0.22 0.29 0.05 Min 4.26 2.98 0.68 0.80 1.82 0.79 1.14 0.40 Max 5.02 3.55 0.79 0.95 2.07 1.01 1.43 0.45

1 2

Description

Male. Macropterous. Coloration ( Fig. 1 ): Body usually pale, either yellow or green, sometimes with dark brown or red markings, with one species having dorsum mostly dark brown to black, wings translucent. Surface and vestiture: Mostly smooth and shiny, impunctate, pronotum weakly rugose; hemelytron translucent, covered with pale short simple setae, sometimes with dark setae on head and pronotum; tibiae with pale brown spine-likesetae.Structureandmeasurements:Head:Indorsalviewheadshort,transverse, with rounded frons ( Fig. 2 D) or slightly elongated and acute ( Fig. 2 A), vertex carinate; eye round, not pedunculate or protruding, contiguous with pronotum ( Fig. 2 A, D); in anterior view head triangular, only slightly elongated, clypeus length somewhat shorter than eye height, not delimited basally, antennal fossa placed slightly above inferior margin of eye, tubercles around antennal fossae slightly upraised, inferior margins of antennal fossa and eyes placed at the same level; eye higher than wide, its inner margin concave ( Fig. 2 C); in lateral view head shorter than high; distance between eye and inferior margin of head subequal to half of eye height, antennal fossa placed above suture between mandibular and maxillary plates, buccula nearly twice as short as labial segment I, distance between buccula and pronotum distinct, but shorter than buccula length ( Fig. 2 B). Labium ( Fig. 2 E): Slightly surpassing posterior margin of metasternum; segment I reaching forecoxa, approximately twice wider than other segments; segment II subequal to or slightly longer than segment I, segment III ca. 0.6–0.7× as long as segment II, segment IV slightly longer than segment III ( Fig. 2 B). Antenna ( Fig. 1 ): Subequal to body length; segment I cylindrical, longer than vertex width, subequal to or shorter than head width, not widened; segment II narrow and cylindrical, 2–3× as long as segment I and slightly thinner than segment I, segment III slightly longer than half of segment II and as wide as segment II; segment IV half length of segment III and slightly thinner than segment III. Pronotum ( Fig. 2 A, D): Trapeziform, with lateral margins rounded, not angulate or carinate and posterior margin almost straight; collar distinctly delimited, narrow; calli shallow. Scutellum and mesoscutum: Scutellum flat, almost as long as wide, shorter than calval somissure; mesoscutum not exposed or slightly exposed. Scent gland evaporative area ( Fig. 2 F): Triangular, with anterior margin slightly shorter than posterior margin. Hemelytron: Costal margin rounded; clavus wide, subequal to eye width basally, indistinctly divided into inner and outer parts with upraising; claval commissure slightly longer than scutellum length; embolium wide, thinner basally; R+M reaching cuneus; cuneus triangular, twice as long as width at base, longer than scutellum, its inner margin straight; cuneal fracture directed anteriorly, slightly notched; membrane cell slightly longer than distance from apex of cell to apex of membrane ( Fig. 1 ). Legs: Femora not modified, not widened; hind tarsal segment I short, tarsal segments II and III subequal in length, each of them ca. 1.5× longer than segment I ( Fig. 2 J); pulvilli present, short ( Fig. 2 G), parempodia wide, longer than claw ( Fig. 2 G–I). Male genitalia: Genital capsule. Not rotated relatively to other segments ( Fig. 2 K), trapeziform, longer than width, its ventral wall longer than dorsal wall, acute posteriorly ( Fig. 4 E, F). Right paramere ( Figs. 3 B, E, I, L, O, 4C): Digitiform, often folded dorsally ( Figs. 3 B, E, I, L), with apical process more or less hook-shaped, directed right or posteriorly. Left paramere ( Figs. 3 C, F, G, M, P, 4D). Twice longer than right paramere, distinctly shorter than aedeagus, L-shaped, widened basally, with apical process narrow. Aedeagus ( Figs. 3 A, D, G, H, K, N, 4A, B). Theca moderately sclerotized, transparent; endosoma subdivided into vesica and conjunctiva, vesica with 3–5 lobes ( Figs. 3 G, 4A); vesica without long spicules, only with weekly sclerotized areas, sometimes lobes with small tubercles or small dense sclerotized spicules apically; conjunctiva entirely membranous; secondary gonopore large, oval; basal part of ductus seminis sclerotized, medial part short, coiled apical part of ductus seminis sclerotized, bowlshaped, secondary gonopore surrounded with loop bearing distinct sculpture.

Female. Coloration ( Fig. 1 ): As in male. Surface and vestiture: As in male. Structure and measurements: As in male, larger than males. Female genitalia ( Fig. 5 ): Dorsal labiate plate ( Fig. 5 A, C, E, G, I) transverse, with anterior margin sclerotized ( Fig. 5 C, G, I) or membranous ( Fig. 5 A, E), sclerotized rings often indistinct, their diameter varying from very small ( Fig. 5 A, E) to relatively large ( Fig. 5 C, G, I); posterior wall of bursa copulatrix with pocketlike interramal lobes, distance between them varies from very small, 3× as short as interramal lobe, to as long as interramal lobe ( Fig. 5 B, D, F, H, J).

Distribution

The genus is known only from Society Islands.

Plant associations

Plant records exist for three Filicicoris species. Adults and nymphs of F. meyeri are known from the fern Nephroplepis hirsulata (Lomariopsidaceae) . Filicicoris viridis specimens were collected from the ferns Angiopteris evecta and Marattia sp., (Mariattiaceae), and a few specimens were collected from the angiosperm Metrosideros collina (Myrtaceae) , with the latter likely sitting records. All material of F. rubromaculus was collected from Piper latifolia (Piperaceae) .

Very few groups of insects are known to live on ferns, including the Heteroptera ( Konstantinov and Knyshov 2015) . Within the Heteroptera , there are a handful of clades belonging to the subfamily Bryocorinae ( Namyatova et al. 2016) that are closely associated with ferns, in particular the tribes Bryocorini ( Konstantinov and Knyshov 2015) and Felisacini ( Namyatova et al. 2016). Additionally, a few species of the brocorine tribe Dicyphini are also associated with ferns ( Knight 1938; Wheeler et al. 1979).

Here we provide the first record of the subfamily Mirinae with ferns. Filicicoris species are known from two phylogenetically distantly fern families, the Lomariopsidaceae and Mariattiaceae ( Christenhusz and Chase 2014), which supports the contention of Konstantinov and Knyshov (2015) that mirids can be associated with distantly related fern clades.

Discussion

Based on the divergent, flattened parempodia and ring-like sclerotization of the secondary gonopore, Filicicoris belongs to the subfamily Mirini ( Schwartz 2008; Cassis and Schuh 2012). According to the descriptions and keys provided in Carvalho (1955), Schwartz (2008) and Cassis and Schuh (2012), Filicicoris belongs to the nominotypical tribe Mirini . Although Filicicoris has a glassy appearance, akin to that found amongst most members of the tribe Hyalopeplini , it does not have the facies of members of this latter tribe. Various authors have reported on the inadequacy of glassy wings in defining hyalopeplines exclusively, with variation within the tribe, and presence in other mirine tribes ( Schwartz 1987, 2008; Chérot 2001). The Hyalopeplini comprises 17 genera, and all are readily separated from Filicicoris by the ecarinate vertex and/or punctate pronotum ( Carvalho and Gross 1979).

There are 298 genera of Mirini known worldwide (Schuh 2002–2013; Carpintero and Chérot 2008; Cho and Kwon 2008; Gapon 2014). We made an extensive survey of mirini diagnoses, and consider Filicicoris to be distinctive, based on the characters given in the diagnosis. Filicicoris is likely related to Lygocoris Reuter, 1875 and allied genera, as they also have a vertical head, carinate pronotum, impunctate or faintly punctate body and green coloration. Filicicoris is similar to Lygocoris as it also has a translucent hemelytron, but it differs in the posterior carina on the vertex being often indistinct medially, and the theca having an apical process ventrally and the vesica has distinct sclerites ( Yasunaga, 1991a). Other similar genera include Neolygus Knight, 1917 , Lygocorias Yasunaga, 1992 and Ryukulygus Yasunaga, 1996. Neolygus differs by having the body covered with golden pubescence, the pronotum is irregularly punctate, the right parameres are L-shaped in most species and the left paramere has a well-developed sensory lobe ( Yasunaga 1991b). Lygocorias differs by the body being uniformly clothed with silky hairs, the right paramere is L-shaped, with an elongate hypophysis and the sensory lobe has a protuberance ( Yasunaga 1992). Ryukulygus differs by having the hemelytra strongly declivous at the cuneal fracture, and the vesica possesses an elongate spicule ( Yasunaga 1996).

Compared to genera from Australian biogeographic region, Filicicoris is similar to Chinamiris in external characters and male genitalia. However, Chinamiris Woodward, 1959 differs in the eye in lateral view being slightly shorter than the head height, the carinate lateral margins of the pronotum, and the hemelytron is opaque, and neither glassy nor translucent ( Eyles and Carvalho 1991). Filicicoris shares some similarities with Tinginotum Kirkaldy, 1902 in structure, but the latter genus has an opaque hemelytron, elongate setae and the vesica has distinct spicules ( Eyles 2000). Diomocoris Eyles, 1999 shares some characteristics with Filicicoris in having green coloration and translucent hemelytron, but differs in the body being clothed with the dense silvery setae, the antennal segment I subequals to the vertex width, the right paramere is L-shaped, and the vesica has a large spicule. Filicicoris may also be related to the New Guinean genus Prolygus Carvalho, 1987 , as the latter has similar genitalia, but differs in the finely puncutate body and the cuneus length being subequal to or slightly longer than the cuneus width at base ( Carvalho, 1987).

Amongst genera inhabiting the Western Hemisphere, we found only three taxa that are similar to Filicicoris , based on their original descriptions. Based on the works of Carvalho (1984) and Carvalho and Costa (1992a), Ganocapsinus Carvalho, 1984 and Ganocapsisca Carvalho and Costa, 1992 are similar to Filicicoris in many diagnostic characters and the parameres of Ganocapsisca bear resemblance to those of Filicicoris . Ganocapsinus differs in having a protruding scutellum, the cuneal fracture is notched, the left paramere has an enlarged sensory lobe and the vesica has a large spicule. Ganocapsisca differs in having large eyes, reaching the gula in lateral view, the antenna are inserted near the upper third of the eye, and the apical part of right paramere is straight. Filicicoris is also similar to Xavantinisca Carvalho and Costa, 1992 in the structure and the shape of parameres, but Xavantinisca differs in the presence of small punctures on the pronotum and hemelytron, the left paramere has dentate outgrowth, and the aedeagus has a spicule ( Carvalho and Costa 1992b).

Key to species

1. Mostly yellow to green, uniform in coloration.................................................. 2

- Mostly glassy to green, with red or black areas on dorsum................................ 5

2. Body pale green or yellow ................................................................................ 3

- Body dark green.................................................................... F. tatarnici sp. nov.

3. Body length 4.3–5.0 in males and females; dorsal labiate plate with sclerotized anterior margin ( Fig. 5 I); posterior wall with distance between interramal lobes subequal to interramal lobe width ( Fig. 5 J); antennal segment I usually longer than head width........................................................................ F. viridis sp. nov.

- Body length in males 3.2–3.4 and in females 3.6–3.9; dorsal labiate plate with membranous anterior margin ( Figs. 5 A, E); posterior wall with distance between interramal lobes ca. 0.3× as long as interramal lobe width ( Figs. 5 B, F); antennal segment I usually shorter than head width......................................................... 4

4. Vesica with six membranous lobes, one of them with small dense pointed spicules apically and another one with small tubercles apically ( Fig. 3 A)........................... ................................................................................................ F. huahine sp. nov.

- Vesica with four distinct lobes lacking small sclerotized spicules, one of the lobes with tubercles apically ( Fig. 3 D)................................................ F. raiatea sp. nov.

5. Body with head, pronotum, scutellum, clavus and marking on corium black; vesica with three lobes ( Fig. 3 H) ..................................................... F. meyeri sp. nov.

- Body with head, anterior part of pronotum and marking covering posterior part of clavus and inner part of corium red; vesica with four lobes ( Fig. 3 K)............... ........................................................................................ F. rubramaculus sp. nov.

Figures

Fig. 1. Habitus of Filicicoris huahine (male and female), F. meyeri (male and female), F. raiatea (male and female), F. tatarnici (male), F. rubramaculus (male and female) and F. viridis (male and female). This figure is published in colour in the online edition of this journal, which can be accessed via http: // booksandjournals. brillonline. com / content / journals / 1876312 x.

Fig. 2. SEM images. Filicicoris meyeri: (A) head and pronotum, dorsal view; (B) head, lateral view; (C) head, anterior view; (E) labium; (F) scent gland evaporating area; (G) pretarsus, lateral view; (H) pretarsus, dorsal view; (I) pretarsus, ventral view; (K) abdomen, lateral view. F. viridis: (D) head and pronotum, dorsal view. F. huahine: (J) tarsus.

Fig. 3. Male genitalia. Filicicoris huahine: (A) vesica in repose, lateral view; (B) right paramere, dorsal view; (C) left paramere, dorsal view. F. raiatea: (D) vesica in repose, lateral view; (E) right paramere, dorsal view; (F) left paramere, dorsal view. F. meyeri: (G) aedeagus in repose, lateral view; (H) vesica in repose, lateral view; (I) right paramere, dorsal view; (J) left paramere, dorsal view. F. rubramaculus: (K) vesica in repose, lateral view; (L) right paramere, dorsal view; (M) left paramere, dorsal view. F. tatarnici: (N) vesica in repose, lateral view; (O) right paramere, dorsal view; (P) left paramere, dorsal view.

Fig. 4. Male genitalia. Filicicoris viridis: (A) aedeagus partly inflated, lateral view; (B) vesica in repose, lateral view; (C) right paramere, dorsal view; (D) left paramere, dorsal view. Genital capsule of F. meyeri: (E) dorsal view; (F) posterior view.

Fig. 5. Dorsal labiate plate, dorsal view. (A) F. huahine; (C) F. meyeri; (E) F. raiatea; (G) F. rubramaculus; (I) F. viridis. Posterior wall of bursa copulatrix, dorsal view: (B) F. huahine; (D) F. meyeri; (F) F. Raiatea; (H) F. rubramaculus; (J) F. viridis.