Chionomus dissipatus Weglarz & Bartlett 2020, new combination
Creators: name: Weglarz, Kathryn M.
name: Bartlett, Charles R
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Delphacidae
Chionomus
Chionomus dissipatus

description: Chionomus dissipatus (Muir, 1926), new combination   
(Figures 8, 22)  
 Delphacodes dissipata Muir, 1926: 33.   
 Syndelphax dissipatus (Muir), comb. by Fennah, 1967: 76.   
 Delphacodes dentis Beamer, 1948b: 102, new synonymy.   
 Delphacodes vaccina Caldwell & Martorell, 1951: 186, new synonymy.   
 Type Locality. Ecuador, Tungurahua Province, Banos.   
 Diagnosis. Body dark brown with white markings. Vertex quadrate; foveae of frons and vertex dark, posterior compartments of vertex light with fuscous markings. Carinae distinct, off-white in color; antennae light brown. Pronotum dark anteriorly with white band along posterior edge, paranota white with dark marks just below eyes. Carinae distinctly white or ivory. Armature of diaphragm quadrate, lined with small teeth on vertical edges; inner and outer angles of parameres diverging, basal angle produced, rounded. Aedeagus tubular, tapering apically, with linear row of teeth on either side. Segment X armed with 4 distinct processes.   
 Description. Color. Macropter. Body dark, brunneous, with white or ivory markings. Carinae of head (including genal carinae) distinct, stramineous to off-white in color, usually with a small amount brown at apex of carinae; stem of Y-shaped carina less evident. Antennae light brown, fuscous at joint of the two segments. Pronotum dark brown, posterior edge (including ventral edge of paranota) white to ivory, carinae distinctly white to ivory. Mesonotum dark, median and lateral carinae light brown in some specimens, frequently females. Legs light brown to stramineous, proximal half of femora infuscate. Forewings hyaline, dark spot just before apex of clavus. Abdomen dark brown, lateral projections of sternites light brown; pygofer and segment X brown. Structure. Body. Length (in mm) macropter ♂ 1.70±0.16 (n=11); female (♀) macropter 1.95±0.13 (n=3); brachypter ♂ 1.66 (n=1); width ♂ 0.70±0.08 (n=19); ♀ 0.78±0.01 (n=3). Head. Vertex length 0.13±0.02 (n=25); vertex width 0.16±0.03 (n=25); frons length 0.31±0.05 (n=32); frons width 0.14±0.03 (n=32). Macropter. Carinae of vertex distinct, stem of Y-shaped carina faint. In lateral view (Figure 8c, d), fastigium rounded; projecting in front of the eye about 1/5th eye length. Carinae of frons and clypeus distinct (Figure 8f), frons subparallel, widest at ventral edge of compound eyes.Antennal segments subequal in length, segment II wider than segment I; 2nd segment sparsely setaceous, bearing sensory pits arranged 3, 3, 2, 2, evenly spaced around segment. Sensory pits surrounded by small black setae. Brachypter. Same as above.   
 Thorax. Macropter. Carinae of mesonotum obscure, median carina ending anterior to scutellum, lateral carinae faint, reaching hind margin. Legs mostly bare; calcar bearing 18–20 small teeth. Brachypter. Same as above; tegmina rounded at apex.   
 Abdomen. Macropter. Compressed dorsoventrally, tapering caudad to truncate apex. Brachypter. Same as above.   
 Genitalia. Pygofer in lateral view (Figure 8h) nearly half as long dorsally as ventrad, ventral margin sinuate. In caudal view (Figures 8g, 23a), 3/4ths as tall as wide, rounded; margins raised, dorsolateral margins produced, carinate. Opening to inner chamber trapezoidal, pointed ventrad. Armature of diaphragm quadrate, toothed on vertical edges, distinctly projecting caudad. Parameres, widest in basal third, basal angle strong, projecting, rounded, mirrored on exterior edge; dorsolaterally diverging, apices nearly flat, lateral margins concave, inner and outer angles approximately equally produced. Aedeagus oval in cross-section, slightly curved dorsad, widest near base, slightly tapering for most of length; aedeagus bearing row of equally spaced teeth on both sides, along ventral edge, sometimes with 2–4 extra teeth just proximal to gonopore; gonopore dorsal, subapical. Segment X quadrate, taller than wide; with 4 processes, first pair short broadly approximated, second pair long, closely approximated. Segment XI produced, about half length of segment X.   
 Plant associations. None reported.   
 Distribution. USA: TX, LA; FL; Puerto Rico; Bahamas, Cayman Islands, Jamaica, St. Thomas; Mexico (Puebla, Veracruz); Guatemala; Honduras; Panama; Brazil (Santa Catarina), Venezuela; Also reported: Ecuador (Muir 1926); Can: NT (Wilson 1992, 1997); Galapagos Islands (Santa Cruz, San Cristóbal) (Fennah 1967, Sinclair 2011).   
 GenBank accession number. Molecular sequence was unable to be generated at the time of this study.   
 Remarks. Chionomus dissipatus is identical to D. vaccina and D. dentis and has priority over these names. The type of D. dissipata was examined and an array of at least 10 paratypes (including topotypes) were examined for D. vaccina and D. dentis. Chionomus dissipatus is closely allied with C. gluciophilus and may be easily misidentified. It can be distinguished by white or ivory carinae of the pronotum, the non-bifurcating armature of the diaphragm, and the pattern of the teeth on the aedeagus. Chionomus dissipatus shares the toothing along the armature of the diaphragm but bears a notch along the dorsal margin, is similar in the shape of the aedeagus but scattered rows of teeth as opposed to parallel evenly spaced rows, and lacks the expansion mirroring the basal angle found in C. dissipatus.   
 This species is also closely allied with C. quadrispinosus which both share 4 processes on segment X. Chionomus quadrispinosus has a similar tooth pattern on the aedeagus but has a quadrate expanded base and is more distinctly upwardly directed.   
 The single specimen reported as D. dentis from Northwest Territories, CAN, is likely mislabed as indicated in Wilson (1992).   
 Type material examined. Holotype Delphacodes dissipata [BPBM]: Brachypterous ♂, “Banos, Or. / Ecuador / XII-28-1922 [Date handwritten] // F.X. Williams / Collector // ♂ // Holotype [Red paper, vertically oriented, affixed to following label] // Delphacodes / dissipata / ♂ Muir/ Type No 1149. [Handwritten, label with black border]”.   
 Paratypes Delphacodes dentis [all SEMC]: Texas: Cameron Co.: Brownsville, 29 Dec 1945, R. H. Beamer, in palm forest (1m ♀); Hidalgo Co., McAllen, 30 Dec 1945, R. H. Beamer (2m ♂, 3m ♀). San Patricio Co., Sinton, 25 Dec 1945, R. H. Beamer (1m ♂).   
 Holotype Delphacodes vaccina [USNM]: Macropterous ♂, “P. R. Acc. No / Isabela, P. R. / 8-29-47 [Date Hand- written]// Delphacid [handwritten]/ HOLOTYPE / vaccina [Handwritten, Pink paper] // [Microvial containing genitalia] // JS Caldwell / Collection / 1959 // Delphacodes ♂ [Handwritten]/ vaccina [handwritten]/ det 49 Holotype [4 is handwritten crossed out 1, Holotype is handwritten]/ JS Caldwell”.
description: Published as part of Weglarz, Kathryn M. & Bartlett, Charles R, 2020, A revision of the planthopper genus Chionomus Fennah (Hemiptera: Fulgoroidea: Delphacidae), pp. 1-63 in Zootaxa 4811 (1) on pages 19-21, DOI: 10.11646/zootaxa.4811.1.1, http://zenodo.org/record/3944031