Holoneurus occidentalis Felt, 1911

Jaschhof, Mathias, 2014, A revision of the types of Neotropical Porricondylinae (Diptera: Cecidomyiidae), Zootaxa 3779 (4), pp. 463-469 : 467-469

Holoneurus occidentalis Felt, 1911

( Figs 7–9, 11 )

Felt 1911: 190.

Type material. Lectotype (designated here). Male, Panama, Canal Zone, Paraíso, reared from larva May 1911, E.P. Felt, from rotting wild fig branch collected by E.A. Schwarz ( NMNH). One wing of this specimen is mounted dry on a separate slide. Paralectotypes. One female and one larva, on separate slides, from locus typicus.

Remarks. The lectotype male is in generally good condition; the genitalia are mounted with the dorsal side facing up. The paralectotype female, mounted with the ventral side facing up, is compressed. The wings of both the male and female are either distorted or extremely pale, which makes it impossible to assess the condition of the hind veins.

Adult description. Male. Head. Eye bridge dorsally 10–11 ommatidia long. Of 14 flagellomeres ( Felt 1911) 12 retained; circumfila ring-shaped, appressed, without extensions; neck of fourth flagellomere 1.1 × node ( Fig. 9 ). Palpus 4-segmented, as long as height of head. Thorax. Both anepisternum and anepimeron setose. Wing. R5 joining C at apex of wing. Rs strongly oblique, in line with R5. R-m+m-cu slightly curved. Both M and CuA1 apparently absent, an observation supported by Felt’s description. Legs. Basitarsi with narrow microtrichose projection apicoventrally. Claws slightly curved, 1 large tooth basally. Empodia rudimentary. Preabdomen. Segment I asetose, terga II–III with rather few setae, terga IV–V with 1 seta, terga VI–VIII asetose, sterna II–VII with 2 transverse bands of setae, sternum VIII evenly setose, setae more numerous on posterior sterna. Terminalia. Tergite IX subtrapezoid, setose. Gonocoxites ( Fig. 7 ): ventral emargination unusually small, U-shaped; antGA as long as distance separating them. Gonostylus parallel-sided, slightly curved, apically rounded, apicodorsally a small brush (no comb) of spines ( Figs 7–8 ). Ejaculatory apodeme and parameres forming complex structure including lateral connections to gonocoxal apodemes; rod-like portion of ejaculatory apodeme as long as parameres, ducts of accessory glands unusually distinct, their ends broadened and somewhat sclerotized, a large sclerotized cap shaped like an inverted U posteriorly of gland ducts, parameres tusk-shaped, apical portion curved ventrad ( Fig. 11 ). Female. Head. Antenna with 14 flagellomeres; circumfila consisting of two rings interconnected by two longitudinal threads; fourth flagellomere with short neck, node almost twice as long as wide. Terminalia. Ovipositor, beginning with segment VI, one third as long as abdomen, slightly protrusible. Tergite IX presumably not enlarged. Basicercus slightly longer than disticercus.

Classification. This species is not a Holoneurus in the current sense (see Jaschhof & Jaschhof 2013) and even its tribal assignment—either to Dicerurini or Porricondylini—is somewhat problematic. The male shows porricondyline characters, such as the circumfila lacking posterior extensions and the parameres being tusk-shaped and discrete, whereas the female is dicerurine-like in that it has 14 flagellomeres and the ninth tergite not enlarged. The latter two female characters are regarded as synapomorphies of Porricondylini by Jaschhof and Jaschhof (2013). There is no reason to doubt that the male and female specimens in question are conspecific, so the character states found are in conflict with each other. All evidence considered, I assume that H. occidentalis is a Porricondylini and that the synapomorphies referred to above should be rated as underlying synapomorphies. As regards the generic assignment, I retain H. occidentalis in Holoneurus for the time being, as there is no other genus available that could absorb this species for any good reason; formally, this species is a Porricondylini incertae sedis. All indications are that H. occidentalis should be classified in a separate genus, which will become clear when its relatives are found and Porricondylini in the Neotropics are generally better known.

Figures

FIGURES 7 – 11. Morphology of male Holoneurus occidentalis (7 – 9, 11) and female Feltomyina polymera (10). 7: genitalia, ventral. 8: gonostylus, dorsal. 9: fourth flagellomere, lateral. 10: ditto. 11: parameres and copulatory organ, ventral. Scale 0.05 mm. agd = accessory gland duct, p = paramere.