Revision of Nearctic Phthinia Winnertz (Diptera: Mycetophilidae) Author Fitzgerald, Scott J. Author Kerr, Peter H. text Zootaxa 2014 3856 3 301 325 journal article 10.11646/zootaxa.3856.3.1 b3ac0e11-ba5f-4b93-bc19-90fa32b14888 1175-5326 251697 1596BF3D-5F7C-4AD8-A533-A4E3910E1B20 Phthinia Winnertz, 1863 : 779 Description. Coloration . Vertex brown; face and clypeus light brown to beige; labella beige; four palpomeres beige. Scape and pedicel beige; flagellomeres brown to dark brown. Thorax beige to brown (sometimes ruddybrown dorsally); scutum sometimes with a hint of dorsocentral stripes. Wing hyaline and unmarked. Halter beige basally, brown distally. Legs beige-brown to brown, generally more pale basally becoming darker distally. Abdomen brown to dark brown; terminalia not significantly contrasting color of abdomen or paler (sometimes bright beige-yellow) and noticeably contrasting color of abdomen. Head . Vertex setose; two or three ocelli, aligned; lateral ocelli larger than mid-ocellus. Eyes setose. Scape and pedicel setose particularly in apical half; 12–14 elongate flagellomeres with dense pale trichia; flagellomeres in contact with each other (with no distal neck); length of first flagellomere varies slightly among species (may be subequal or longer than second flagellomere). Face and clypeus setose; four visible palpomeres. Thorax ( Figs. 2 , 31). Pronotum with strong setae. Scutum shining, short, strongly arched, covered with scattered small setae and rows of stronger dorsocentrals and laterals; scutellum setose, typically with 2–4 stronger bristles (although when 4 sometimes only 2–3 apparent and sometimes all setae are shorn off); the apical pair strongest. Mediotergite with several setae laterally; laterotergite with or without setae; remaining thoracic sclerites bare. Legs. Legs very long and slender ( Fig. 1 ); first tarsomere of foreleg much longer than foretibia (approx. 1.5 to 2.5 times as long). Tibial spurs 1:2:2, short, approx. as long as tibial width at apex. All legs with dense, minute, irregularly arranged trichia. Anteroapical depressed area of foretibia present. Mid- and hind tibia with a row of minute anterior and dorsal setae; hind tibia sometimes with minute posterior setae; foretibia without rows of setae. Basal half of midtibia with slender, elongate, less-sclerotized, slit-like, sensory organ in both sexes. Wings ( Figs. 3 , 32 ). Membrane moderately to densely covered with macrotrichia (though an undescribed Oriental species apparently lacks macrotrichia (Ševčík 2008)) ; microtrichia present and irregularly arranged (not in distinct longitudinal rows); microtrichia sometimes unevenly dispersed (e.g. P. fasciata Freeman has microtrichia only close to the veins). C extending variable distance beyond apex of R5; Sc complete, bare dorsally, reaching C before base of Rs and sometimes before base of r-m; sc-r present, at approximately the halfway point of Sc; R1 long, reaching C near wing tip; R4 absent; Rs oblique, shorter than to subequal to r-m; r-m longer, shorter, or subequal to stem of M; medial fork complete, but base of M1 sometimes faint ( Fig. 32 ); stem of medial fork shorter than fork; origin of medial fork before origin of cubital fork; cubital fork complete, forking distal to fork of M; CuA2 sinuous; A1 ending far from wing margin, fading out before level of Cu fork, diverging slightly ( Fig. 3 ) to greatly ( Fig. 32 ) from stem of CuA. Abdomen setose, long and slender. Male terminalia rather variable. Cerci short, lobate, apically rounded with small setae ( Fig. 11 ) to elongate, apically acute, and each with a very strong apical seta ( Fig. 35 ). Hypoproct forming a pair of rounded setose lobes ventral to cerci ( Fig. 35 ); may be much smaller than cerci ( Fig. 35 ) or developed into a pair of lobes longer and broader than cerci ( Figs. 4, 6 ). Parameres forming medially fused dorsal plate; thin and lightly sclerotized to heavily sclerotized and strongly developed ( Fig. 36 ). Homology of components of the sperm pump require further investigation, but several sclerotized structures including at least an ejaculatory apodeme are present. Tergite 9 ranging from a very narrow sclerotized strip just anterior to cerci ( Fig. 27 ) to welldeveloped ( Fig. 35 ) and either simple in shape or with lateral lobes (as in P. parafurcata Oliveira & Amorim ). Gonocoxites ventromedially fused ( Figs. 24 , 29 ) or not fused ( Fig. 7 ); sometimes with variously developed lobes posteriorly ( Figs. 39, 40 ), posterodorsally ( Figs. 4, 5 ), posteroventrally ( Figs. 22, 24 ), or on inner ventromedial surface of gonocoxite as a hypandrial lobe ( Fig. 19 ). Gonostylus articulating on dorsomedial surface ( Fig. 23 , 36 ) or at posterior apex of gonocoxites ( Figs. 9 , 28 ); gonostylus variously developed, but often with multiple lobes. Female terminalia with two-segmented cerci ( Figs. 8 , 38); apical segment fleshy ovate. Gonapophysis 9 apically acute or digitate; shape useful in distinguishing species.