Cryptochironomus mantiqueira, Silva, Fabio Laurindo Da, Strixino, Susana Trivinho & Oliveira, Heliana Rosely Neves, 2010

Silva, Fabio Laurindo Da, Strixino, Susana Trivinho & Oliveira, Heliana Rosely Neves, 2010, New species of Cryptochironomus Kieffer, 1918 (Diptera: Chironomidae: Chironominae) from Brazil, Zootaxa 2614, pp. 18-32 : 23-26

Cryptochironomus mantiqueira sp. n.

(Figs. 13–24)

Type material. Holotype male, BRAZIL: São Paulo State, Campos de Jordão, Galharada stream, 08/xi/1999, M. T. Suriano. Paratypes: 1 pupa as previous except for 13/xi/1999. 1 pupa as previous except for 14/xi/1999. 2 larvae as previous except for 12/xi/1999.

Etymology. " Mantiqueira " is a Tupi indigenous name, here used as a noun in apposition. Serra da Mantiqueira is the name for the Brazilian mountain range where the new species was collected. Its meaning is "home of the rain" (amanty = rain; querd = home or a place for stopping overnight).

Diagnostic characters. Cryptochironomus mantiqueira differs from other Cryptochironomus species by combination of the following characters. Adult male: hypopygium with superior volsella with narrower apex compared to base, with 3 long setae apically; inferior volsella roughly bean shaped, partially covered by superior volsella, with 4 long setae. Pupa: cephalic tubercles long, robust, apically pointed; anal lobe with 120 filaments. Larva: head capsule length of about 288–300 μm, AR 0.96–1.38.

Description. Male (n = 1)

Dimensions. Total length 4.53 mm. Wing length 2.35 mm. Total length/wing length 1.93. Wing length/ length of profemur [2.50] 2.07–2.50, 2.23.

Coloration. Head yellowish brown, flagellum and maxillary palp pale brown. Thorax yellowish brown with brown mesonotal stripes and posteromedian region darkened. Scutellum pale brown. Wing membrane transparent and veins pale brown, without spots. Abdomen including hypopygium brown.

Head. Eyes ratio 1.83. Flagellum 1075 μm long; AR 1.73. Palpomere 1–5 lengths (in μm): 38; 52; 186; 141; 223. Frontal tubercles 22 μm long, 9 μm wide. Temporal setae 16, irregularly biserial. Clypeus with 12 setae.

Thorax. Acrostichals 24, biserial, beginning near antepronotum; dorsocentrals 12, uniserial; prealars 4; supraalar 3. Scutellum with 20 biserial setae. Scutal tubercle present.

FIGURES 13–18. Cryptochironomus mantiqueira sp. n., pupa. 13. Cephalic tubercles. 14. Thorax. 15. Basal ring. 16. Abdomen. 17. Sternite I. 18. Armature on abdominal segments: a. hook on 2nd segment, b. spines on 4th segment, c. spines on 7th segment.

Wing 0.68 mm wide. Membrane without setae. Brachiolum with 2 setae; R with 20 setae; R1 with 12 setae; R4+5 with 16 setae. Squama fringed. R2+3 ending close to, but distinctly separate from R1. VR = 1.06. Legs. Mid leg with two pseudospurs on Ta1–4. Tarsal claws on fore leg slender and hook-like, pulvilli well developed. Lengths and proportions of legs as in Table 3.

fe ti ta1 ta2 ta3 ta4 ta5 LR BV SV p1 1046 1108 – – – – – – – – p2 1123 1138 769 369 307 169 123 0.68 3.13 2.94 p3 923 831 – – – – – – – – Hypopygium ( Figs. 19–20 ). Tergite IX with 12 strong setae. Anal point slender, short, 52 μm long. Superior volsella with narrower apex compared to base, with 3 long setae apically. Inferior volsella roughly bean shaped, partially covered by superior volsella, with 4 long setae ( Fig. 20 ). Gonostylus short about 1.55 times as long as wide. HR 1.03.

Pupa (n = 2 unless otherwise stated, tentatively associated and not reared)

Dimension. Abdomen 5.3–6.2 mm long.

Coloration. Exuviae pale brown.

Cephalothorax (Figs. 13–15). Cephalic tubercles 330–430 μm long, elongated, robust, apically pointed; frontal setae 35–60 μm long, placed subapically (Fig. 13). Wing sheath 1.72–1.77 mm long. Thorax extensively granulose (Fig. 14); scutal tubercle present; prealar tubercle absent; antepronotals 2, precorneals 2, dorsocentrals 4. Basal ring rounded (Fig. 15).

Abdomen (Figs. 16–18). Shagreenation on T I–VI covering most of tergite, with fine reticulations; T VII and anal lobe finely reticulate and with small spines; T VIII with small spines. Posterior row of recurved hooks, interrupted medially, extending nearly on 1/3 the width of tergite II (Figs. 16, 18a); spines on 4th and 7th segments as in figures 18b and 18c, respectively. T II–VIII and S I–V with posterior row of spines; S VI–VIII with few spines (Fig. 15). S I with anterolateral shagreen patches (Fig. 17). Pedes spurii B present on segment II. Pedes spurii A present in segment IV, reduced to few spinules. Abdominal chaetotaxy as in Table II. Anal lobe with complete fringe of 120 taeniae.

4th instar larva (n = 2 unless otherwise stated, tentatively associated and not reared)

Coloration. Body reddish; head yellowish, postmentum and frontoclypeus without dark areas. Procercus and anal setae pale brown. Posterior parapod claws all pale yellowish.

Head 288–300 μm long, 231–244 μm wide.

Antenna ( Fig. 21 ) 106–154 μm long, with 5 segments, basal antennal segment 62–75 μm long, with ring organ 40–43 μm from base. AR 0.96–1.38. Antennal blade 55 (1) μm long, arising in distal 1/3 of segment 2, reaching almost antennal apex. Style present on segment 2.

Maxilla. Basal palp segment 29–43 μm long, 11–15 μm wide, with ring organ 20 μm from base.

Labrum ( Fig. 22 ). SI short, blade-like; SII shorter, more robust blade-like, 28 (1) μm long; SIII very short, seta-like; SIVa elongated, 3 segmented. Pecten epipharyngis divided in 3 lobes. Premandible with 4 teeth, progressively decreasing in size towards base; brush present.

Mandible ( Fig. 23 ) 86–92 μm long with apical tooth and 2 inner triangular teeth dark brown. Seta subdentalis slender, base wider than apex.

Mentum ( Fig. 24 ). With a large middle white tooth and 5 dark lateral teeth. Ventromental plate about 1.11– 1.26 times as long as width of mentum, course striated.

Abdomen. Procercus 0.89 (1) times as long as wide, with 7–8 anal setae. Posterior parapod with simple claws.

Remarks. The male of C. mantiqueira can be separated from other Cryptochironomus species based on shape of superior and inferior volsellae. The shape of the cephalic tubercles is sufficient to distinguish the pupa of C. mantiqueira from other Neotropical species. The larva of C. mantiqueira is similar to C. brasiliensis , but differs by the length of labral setae II, those are longer in C. mantiqueira . The larvae of C. mantiqueira were collected in sandy bottom of streams in Campos de Jordão Park; the adult was collected with light trap in the same locality. The larva, pupa and adult were associated considering that in this locality only one Cryptochironomus morphotype was collected in all life stages.

Figures

FIGURES 19 – 24. Cryptochironomus mantiqueira sp. n., male (19 – 20) and larva (21 – 24). 19. Hypopygium. 20. Superior and inferior volsellae. 21. Antenna. 22. Labrum, epipharynx and premandible. 23. Mandible. 24. Mentum.