Allocladius quadrus Andersen, Saether & Mendes

Mauad, Melina, Siri, Augusto & Donato, Mariano, 2013, New species of Pseudosmittia Edwards, 1932 and new records of Allocladius Kieffer, 1913 (Diptera: Chironomidae, Orthocladiinae) from South America, Zootaxa 3694 (5), pp. 445-460 : 456-457

Allocladius quadrus Andersen, Saether & Mendes

Allocladius quadrus Andersen, Saether and Mendes, 2010: 17 ; Ferrington & Saether (2011: 96).

Material examined. ARGENTINA: 2 males, Salta, Quebrada del Agua, 24º 30' 33.0'' S, 68º 10' 52.6'' W, 3678 m a.s.l., 11.i.2005, sweep net, M. Donato; 1 male, Río Negro, P.N. Nahuel Huapi, laguna Los Juncos, 41º 03' 37.9'' S, 71º 00' 34.3'' W, 906 m a.s.l., 12.xii.2007, sweep net, A. Garre and F. Montes de Oca (MLP).

Male (n = 3, except when otherwise stated). The following measurements are different from the original description. Total length 2.3–2.4 mm. Wing length 1.35–1.55 mm. Total length/wing length extended to 1.7. Wing length/length of profemur 2.70–3.04.

Head. AR 1.2–1.2. Minimum length of ultimate flagellomere 390. Tentorium 115–124 long, 22–34 wide. Stipes 115–120 long, 7–10 wide. Palpomere lengths (2–5) 39–46, 71–83, 88–103, 120–127. Third palpomere with 2 lanceolate sensilla clavata, 19–21 long.

Thorax. Dorsocentrals 7–10, acrostichals 3–5, scutellum with 6–7 setae.

Wing. Minimum value for VR 1.25.

Legs. Width at apex of fore tibia 25–29, mid tibia 24–30, of hind tibia 37–42. Comb of 13–16 setae. Length and proportions of legs as in Table 6 .

Hypopygium. Anal point 40–41, including 26 long basal sclerotized part with 8 setae and 14–15 long bare, hyaline distal part. Tergite IX with 6–8 setae in addition to those on anal point. Phallapodeme 44–46 long. Transverse sternapodeme 61–76 long. Virga 5 long, 10–14 wide. Pars ventralis (Fig. 44) single, subquadrangular, 75–93 (2) long, 80–103 (2) wide. Gonocoxite 166–181 long. Inferior volsella reaching to 0.43–0.46 gonocoxite length. Gonostylus 71–73; megaseta 7–10.

Remarks. The specimens from Quebrada del agua in Salta province were collected at a Punean spring and the specimen collected at laguna Los Juncos in Rio Negro province at a small temporal lagoon ( Fig. 13 ). This lagoon is located in the Patagonian steppe. These new records define the distributional pattern of A. quadrus as Andean Patagonian.

The analyses of the data matrix using only male characters as defined by Ferrington & Saether (2011) under concavities K=2 to K=20 showed the best group support under K=5. In this concavity the analysis yielded 7 trees (Fit= 63.62, CI= 0.17, RI= 0.56) and the resulting strict consensus tree is shown in Figure 14 . The species P. larga and P. saetheri conform a clade supported by the characters Cu1 straight [21 (0)]; superior volsella with strong orally curved microtrichia [57 (1)] and inferior volsella without accessory lobe [63 (1)]. This clade is located in a major clade in the angusta group of species.

The species P. trapezoidea is the sister group of the clade (( P. propetropis ( P. tropis – P. lamellata )) sharing the characters inner verticals of temporal setae absent [5 (1)] and virga 35–57 long [46 (1)]. This species is part of a major clade constituted by all the species of the brevifurcata group except P. brevifurcata that is located in a clade with several species of the xanthostola group.

In the strict consensus tree Allocladius fortispinatus is place at the base of the Allocladius clade as the sister species of the rest of the species of the genus except A. wirthi sharing the synapomorphies postorbitals present [7 (0)], anal point at least extreme apex without microtrichia or anal point absent [34 (0)], and oral projections of transverse sternapodeme well developed [41 (0)].

Figures

FIGURE 13. Map showing the new records of Allocladius globosus and A. quadrus. A. globosus: square, known records; triangle, new records. A. quadrus: star, known records; circle, new records.

FIGURE 14. Strict consensus tree obtained from the 7 trees yielded under K = 5 (Fit = 63.62, CI = 0.17, RI = 0.56). Number above branches indicates absolute Bremer support and number below branches indicates relative Bremer support.

Tables

TABLE 6. Lengths (in µm) and proportions of legs of Allocladius quadrus (male) (n = 3, except when otherwise stated). For abbreviation explanations see Table 1.

fe	ti	ta1	ta2	ta3
P1 470–510	570–620	260–270 (2)	160–180 (2)	110 (1)
P2 550–600	570–610	220–250	130–140	110 (2)
P3 570–610	600–630	350–350 (1)	180–180 (1)	150 (1)
ta4	ta5	LR	BV	SV
P1 70 (1)	70 (1)	0.43–0.44 (2)	3.32–3.32 (1)	4.19–4.23 (2)
P2 60–80 (2)	60–70 (2)	0.39–0.41	3.65–3.83 (2)	4.84–5.09
P3 80 (1)	70 (1)	0.56–0.56 (1)	3.31–3.31 (1)	3.54–3.54 (1)
Cladistic analysis