Litocladius Mendes, Andersen et Saether

Mendes, Humberto Fonseca & Andersen, Trond, 2008, A review of Antillocladius Saether and Litocladius Mendes, Andersen et Saether, with the description of two new Neotropical genera (Diptera, Chironomidae, Orthocladiinae), Zootaxa 1887 (1), pp. 1-75 : 56-57

Litocladius Mendes, Andersen et Saether

Litocladius Mendes, Andersen and Saether, 2004: 72 .

Type species: Litocladius mateusi Mendes, Andersen et Saether, 2004 , by original designation.

Other included species: L. confusus sp. n., Litocladius floripa sp. n.

Diagnostic characters: The males can be separated from other orthoclad genera by the combination of the following characters: acrostichals divided into anterior decumbent, middle simple, and posterior scalpellate; virga long with lateral lamellae; costal extension short (<length of RM); setae on wing membrane and squama; supraalars present; and anal point with several lateral setae. The female genitalia cannot be separated from those of Antillocladius . However, the acrostichals are presumably of the same type as in the males. The pupa can be separated from Gymnometriocnemus by the absence of frontal setae and by having all thoracic setae reduced. The larva is unknown.

Generic diagnosis:

Imago. Small to medium sized species, wing length about 1.4 mm.

Antenna. Female antenna with 5 flagellomeres. Male antenna with 13 flagellomeres, groove beginning at flagellomere 3, sensilla chaetica on flagellomeres 2, 3 and 13. Male antennal ratio about 1.5.

Head. Eye naked, without dorsomedian extension. Temporal setae divided into weak inner verticals, stronger outer verticals, postorbitals absent or few. Third palpomere with about 3 sensilla clavata subapically, longest about 20 µm long; with or without strong apical spines.

Thorax. Antepronotum well developed lobes meeting medially along short suture. Acrostichals beginning close to antepronotum, composed of few anterior strong decumbent, weak simple, and posterior scalpellate; dorsocentrals uniserial; prealars uniserial; supraalar 0–1; scutellars uniserial, occasionally biserial.

Wing. Anal lobe developed. Costa at most moderately extended. R 2+3 running and ending midway between R 1 and R 4+5; R 4+5 ending slightly distal to M 3+4; FCu far distal to RM; Cu 1 straight; PCu ending distal to FCu; An ending proximal to FCu. Veins bare or setose. Membrane with apical setae in female; male without or with setae apically in cells r 4+5, m 1+2 and m 3+4. Anal lobe well developed. Squama setose.

Legs. Pseudospurs, sensilla chaetica and pulvilli lacking. Comb and tibial spurs normal; spurs with small denticles.

Abdomen. Tergites with irregularly arranged setae.

Male hypopygium. Anal point long, pointed, with few lateral setae, without microtrichia near apex. Phallapodeme and aedeagal lobe well developed. Anterior margin of sternapodeme weakly arcuate, oral projections moderately developed. Virga consisting of two long, strong spines with lateral lamellae. Inferior volsella with anterior dorsal triangular part and a more rounded ventral, posterior part or adpressed to gonocoxite. Gonostylus without heel, crista dorsalis rounded and well developed. Megaseta normal.

Female genitalia. Gonocoxapodemes curved and meeting anterior of vagina. Gonocoxite well developed, with few long and some short setae. Tergite IX divided. Gonapophysis IX apparently with large ventrolateral lobe covering apodeme lobe, and narrow, line-like dorsomesal lobe. Labia relatively large, pointed. Cerci small. Seminal capsules small to medium-sized, circular, with triangular neck. Spermathecal ducts not observable in available specimen.

Pupa. Small, total length 2.3 mm.

Cephalothorax. Frontal setae absent. Frontal apotome smooth. Antennal sheath with basal pearl row. Ocular field with 2 reduced postorbitals. Thoracic horn absent. Three weak precorneals situated in narrow triangle. Two weak antepronotals. Dorsocentrals very small, in two groups of two. Thorax and wing sheath smooth.

Abdomen. Tergite I–VIII covered with coarse shagreen except along anterior margin, tergite IX with strong shagreen except along posterior margin. Sternites I–IV bare, sternite V with median shagreen, sternites VI–VII with slightly more extensive median and lateral shagreen, sternite VIII with extensive shagreen, sternite IX with anterolateral shagreen. Tergite II without posterior hooklets. Tergites without posterior row of weak spines. Conjunctives bare. Pedes spurii A and B absent. Apophyses weak, nearly straight. Segment II– VIII with 2 weak, hair-like L setae . Anal lobe without macrosetae, male genital sac overreaching anal lobe.

Larva. Unknown.