Xenohelea Kieffer
Creators: name: Borkent, Art
Publisher: name: Zenodo
Year: 2014
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Ceratopogonidae
Xenohelea

description: Xenohelea Kieffer
(Figs. 28C, 31D, 40F, 46F, 53C, 69B, 77D)
DIAGNOSIS: Only pupa of Ceratopogonidae with abdominal tergite sensilla D-8-IV and D-9-IV on the apex of a single lobed, flattened tubercle (Fig. 69B).
DESCRIPTION: Total length = 5.59 mm. Without larval exuviae retained on abdomen. Exuviae with flagellum appressed against lateral margin of midleg, wing (as in Figs. 16B, 33B). Ecdysial tear around base of antenna, along lateral margin of face to palpus (as in Figs. 17C, 79H). Head: Dorsal apotome missing; dorsolateral cephalic sclerite (as in Fig. 13H) fused to scutum, each side separated medially by dorsal apotome in whole pupa; mouthparts (Fig. 28C) with mandible well-developed, lacinia absent; palpus extending just posterior to posterolateral margin of labium; labium entire (not divided medially); apex of antenna (Fig. 40F) anterior to posterior extent of midlength portion of midleg (portion lateral to mesosternum), narrowed posteriorly; sensilla: dorsal apotomals—uncertain; dorsolateral cephalic sclerite sensilla—1 seta, 1 campaniform sensillum; clypeallabrals (Fig. 28C)—2 slender setae; oculars (Fig. 28C)—2 setae, 1 campaniform sensillum. Thorax: Prothoracic extension (Fig. 28C) wide, well-developed but narrow dorsolaterally, not extending to antenna; mesonotum without tubercles, not extending posteromedially, not dividing metathorax medially (Fig. 53C); respiratory organ (Fig. 46F) length/width = 4.83, elongate, moderately slender, somewhat flattened apically, with pores closely abutting at apex of respiratory organ, arranged in single curved row, outer surface with some wrinkles, with short, wide pedicel, base with moderate elongate posteromedial apodeme, membranous base of respiratory organ short, tracheal tube straight to slightly curved along length, with spirals restricted to base, wrinkles to half length; wing (Fig. 40F) without apical tubercle or angle, separated medially by fore-, midlegs; halter apex and hind leg (similar to Fig. 33J) broadly abutting; halter apex extending posteriorly to 1/4 length of tergite 2; legs (Fig. 40F) with lateral margin of foreleg near midlength of wing evenly curved; hind leg visible at lateral margin of wing (as in Fig. 33I); female with apex of foreleg ventral to apex of midleg; apex of hind leg abutting apex of midleg laterally; sensilla: anteromedials—2 elongate setae (as in Figs. 31L–M); anterolaterals—1 moderately long seta; dorsal setae (Fig. 31D)—D-1-T, D-2-T, D-4-T, D-5-T setae, D-3-T campaniform sensillum, D-4-T uncertain, broken along length, D-3-T lateral to D-4-T; supraalar 2—campaniform sensillum; metathoracics (Fig. 53C)—1 campaniform sensillum; M-3-T distant from margin of metathorax (at least 1/3 length of metathorax). Abdomen: with tergites 1–7 with medial area with stripe, 2 spots, sternites 3–7 with medial stripe, anterolateral spot, segment 2 as wide or slightly wider than segment 3, segments with undivided, thin to thick setae, with rounded to pointed, short to moderately elongate tubercles, tergites or sternites entire, each without membranous disc; segment 9 (Fig. 77D) not strongly modified, terminal processes closely approximated basally, each projecting posterodorsolaterally, tapering to pointed apex; sensilla: tergite 1 (Fig. 53C) with 7 setae, 3 campaniform sensilla (1 broken seta?), including 3 lateral sensilla, D-2-I, D-3-I closely approximated, D-7-I situated anteriorly near D-3-I; segment 4 (Fig. 69B)—D- 2-IV, D-3-IV moderately elongate setae, D-2-IV on short tubercle; D-5-IV, D-8-IV, D-9-IV short to moderately elongate setae; D-5-IV on single tubercle, D-8-IV, D-9-IV on single flattened tubercle, posterior dorsal sensilla in transverse row, arranged medially to laterally: D-5-IV, D-4-IV, D-8-IV, D-9-IV; D-7-IV near D-3-IV; L-1-IV short seta on short tubercle, just anterior of base of tubercle with L-2-IV, L-3-IV; L-2-IV, L-3-IV, L-4-IV short setae on rounded, flattened tubercles, L-2-IV, L-3-IV on single tubercle, V-5-IV, V-6-IV, V-7-IV short setae on short tubercles, all closely approximated; segment 8 without D-3-VIII, without L-1-VIII; with V-5-VIII, V-6-VIII on single tubercle, V-5-VIII tiny, V-6-VIII elongate; segment 9 (Fig. 77D)—with D-5-IX campaniform sensillum, D- 6-IX possibly absent (not discernable).
DISTRIBUTION AND HABITAT: The genus Xenohelea is known from 14 species in the Afrotropical and Oriental Regions (Borkent 2014). The only known pupa was collected in mud from "aus einem klaren Gewässer" (a clear body of water) (Mayer 1957).
TAXONOMIC DISCUSSION: Only one species of Xenohelea is known as a pupa (Tables 2–3). Male and female pupae of Homohelea and Sphaeromias, two genera closely related to Xenohelea, are sexually dimorphic in the arrangement of their forelegs. In males, the foreleg is relatively short (Figs. 40A, D) while in females the foreleg overlaps the midleg entirely (Figs. 40B, E). Only one female Xenohelea is known (Fig. 40F) and it is likely that the male, once discovered, will share this dimorphism (see character 44).
Mayer (1957) described the same specimen as I studied here, the only one known for the genus. He shows D- 8-IV and D-9-IV on separate, abutting tubercles but they are clearly located together on a single rounded tubercle. In addition, he showed V-5-IV and V-6-IV on a single tubercle, which was indeed present on one side but slightly separated on the other (that drawn here). The dorsal apotome of the single available specimen was missing and cannot, therefore, be characterized.
The female holotype was remounted in Canada Balsam from drying and damaged Hoyer's, perhaps accounting for some slight differences between the description here and that by Mayer (1957) (e.g. body length).
MATERIAL EXAMINED: X. galatea: 1 pupal exuviae (of holotype), Nametil Quelimane, Mozambique, 7-I- 1940 (SAIM).
description: Published as part of Borkent, Art, 2014, The Pupae of the Biting Midges of the World (Diptera: Ceratopogonidae), With a Generic Key and Analysis of the Phylogenetic Relationships Between Genera, pp. 1-327 in Zootaxa 3879 (1) on pages 99-100, DOI: 10.11646/zootaxa.3879.1.1, http://zenodo.org/record/4949051