Marshallicona Cerretti & Pape, 2020

Cerretti, Pierfilippo, Badano, Davide, Gisondi, Silvia, Giudice, Giuseppe Lo & Pape, Thomas, 2020, The world woodlouse flies (Diptera, Rhinophoridae), ZooKeys 903, pp. 1-130 : 1

Marshallicona Cerretti & Pape gen. nov. Figs 1C , 15

Unambiguous character state changes

(Table 1 , Fig. 20 ). Global apomorphies: none; local apomorphies: 2:1, 9:1, 43:1, 51:1, 52:1, 56:1, 66:0, 68:1.

Diagnosis.

Head: head higher than long in lateral view. Facial ridge 0.4 times as long as frons. Ocellar setae virtually absent. Frons approx. 0.8 times as wide as compound eye in dorsal view. Median vertical setae strong, subparallel. Six to eight medially crossed frontal setae, slightly reclinate, descending to level of upper margin of scape. Fronto-orbital plate with few short setulae confined to upper half. Four or five proclinate orbital setae (posterior two slightly lateroclinate). One weak upper lateroclinate orbital seta (usually not distinguishable from uppermost frontal setae). Parafacial bare, at its narrowest point approx. as wide as width of postpedicel. Vibrissal angle receding. Vibrissa well developed, arising at level of lower facial margin. Lower facial margin not sunken though not visible in lateral view. Facial ridge concave with decumbent setulae on lower 1/3-2/5. Face slightly concave, antennae not hidden from view in profile. Antenna approx. as long as height of gena. Postpedicel sub-ovoid, approx. 1.5 times as long as pedicel. Arista bottlebrush-like, trichia longer that maximum diameter of arista. Arista thickened in proximal 1/5 or less; second aristomere at most as long as wide. Lunule hidden by inner anterior margins of fronto-orbital plate. Gena, in profile, approx. 1/2 as high as compound eye. Palpus stout, clavate, with a few thin setulae on apical 1/4.

Thorax: prosternum bare. Postpronotum with two setae. One postsutural supra-alar seta (i.e., first and third post sutural supra-alar setae absent). Scutellum with one pair of well-developed basal setae and one pair of strong, horizontal and crossed apical setae; basal setae placed dorsally with respect to apical setae. Anatergite bare. Subscutellum moderately swollen, not fully sclerotised. Metathoracic spiracular lappets virtually absent. Lower calypter distinctly tongue-shaped (ground-plan trait of Rhinophoridae ) (Fig. 2E ). Costal sector cs2 setose ventrally. Costal spine not differentiated from general costal setae. Costal sector cs5 longer than costal sector cs2 (Fig. 15E ). Vein R1 dorsally setose on distal 1/4. Base of R4+5 entirely bare. Bend of vein M1 shallow, well removed from wing margin. Crossvein dm-m forming an acute angle with proximal section of M4. Vein CuA+CuP not reaching wing margin. Preapical anterodorsal seta of fore tibia approx. as long as preapical dorsal seta. Fore tarsus not compressed. Tibiae of mid and hind leg normally developed. Mid tibia with one anterodorsal seta. Hind tibia with 3 dorsal preapical setae.

Abdomen: slightly elongated, virtually without microtomentum and without distinct marginal and discal setae.

Male terminalia (Fig. 15F-H ): posterior margin of sternite 5 with a deep median notch; lateral lobe rounded posteriorly. Tergite 6 bare, medially divided into two hemitergites; tergite 6 divided from syntergosternite 7+8 by a wide membrane. Connection between sternite 6 and syntergosternite 7+8 on right side membranous. Cerci well developed, not fused medially. Basal 1/3 of cerci convex and covered with short setae; distal 2/3 straight and narrowly digitiform (branches symmetrically diverging and well separated). Surstylus well developed, lobe-like in lateral view; lateral side of surstylus broadly convex at approx. mid length. Surstylus not fused to epandrium. Bacilliform sclerite firmly fused to laterobasal margin of surstylus. Hypandrial arms not fused medially. Connection between phallic guide and pregonite sclerotised. Postgonite without anterior seta. Epiphallus well developed and attached dorsomedially to basiphallus. Extension of dorsal sclerite of distiphallus entirely fused medially into a single sclerite and proximally fused to dorsal sclerite of distiphallus. Median process of ventral sclerotisation of distiphallus present, divided medially into two hemisclerites, which are both proximally fused to ventral plate of distiphallus. Acrophallus simple and scale-like spinules present lateroventrally.

Distribution.

Neotropical - Ecuador.

Type species.

Marshallicona quitu Cerretti & Pape, sp. nov., by present designation.

Etymology.

The generic name is a composite word formed from the name of our colleague and friend Steve Marshall, who collected the type series and took the photo of a living specimen (Fig. 1C ), and from the Latin noun ' icona ', meaning image, in honour of Steve’s remarkable skills in natural history photography. The name should be treated as a feminine noun.

Figures

Figure 1. Rhinophoridae photographed in nature. A Bezzimyia sp. (Ecuador) B Bixinia winkleri (Australia) C Marshallicona quitu (Ecuador) D Paykullia maculata (Finland) E Stevenia sp. (Italy) F Tricogena rubricosa (Finland) G Phyto sp. (Italy). Photographs by Steve Marshall (A, C), P. C. (B, E, G), Hakon Haraldseide (D, F).

Figure 2. Morphological terminology of Rhinophoridae, head, thorax and abdomen. A Chaetotaxy of head, thorax and abdomen in dorsal view B, C arrangement of setae of postpronotum: B three setae arranged in shallow triangle C three setae standing in a nearly right-angled triangle D thorax, sclerites and chaetotaxy, in lateral view E wing veins and cells. Drawings by Giulia Bellanti.

Figure 15. Marshallicona quitu gen. et sp. nov. (Ecuador) ♂. A Habitus in lateral view B abdomen in dorsal view C head in lateral view D head in frontal view E wing in dorsal view F, G epandrial complex in posterior view (F) and lateral view (G) H hypandrial complex in lateral view [A-D holotype, E-H paratype].

Figure 20. Phylogeny of Rhinophoridae based on morphological evidence. Single tree obtained under IW (total fit: 62.33), enforcing a k-value of 4, with unambiguous character state changes mapped above branches [black squares: global apomorphies (i. e., uncontradicted and unreversed apomorphic character states; white squares: local apomorphies (i. e., homoplasious character state due to convergence or reversal)] and new taxa highlighted in bold.