Colonization of leaf litter of two aquatic macrophytes, Mayaca fluviatilis Aublet and Salvinia auriculata Aublet by aquatic macroinvertebrates in a tropical reservoir

Decomposition and colonization of S. auriculata and M. fluviatilis by macroinvertebrates were analyzed during 40 days to determine whether differences existed on colonization by aquatic macroinvertebrates of two macrophytes with distinct habits (submerged versus fluctuant). Leaf litter of S. auriculata and M. fluviatilis were incubated in 24 litter bags (12 of each species), in a small reservoir surrounded by a cerrado fragment with low level of anthropic impact. After 10, 20, 30 and 40 days, the litter bags were removed and aquatic macroinvertebrates community was analyzed. Two hundred twenty macroinvertebrates were associated with S. auriculata and 261 were associated with M. fluviatilis, identified in 24 taxa. Both macrophyte species were colonized mainly by macroinvertebrate predators. Ablabesmyia with predator and collector food mechanisms was present in all sampling. The data showed an expressive increase of abundance during the process of decomposition and a decrease at the end of the experiment, in both macrophytes. Cluster analysis permitted inference that the colonization of the leaf liter by macroinvertebrates was determinated by incubation time of leaf litter not by the habit of macrophytes (submerged or fluctuant)

Macroinvertebrados bentônicos dos sistemas aquáticos da estação de piscicultura do CEPTA/IBAMA, Pirassununga, SP.

With the objective to verify the distribution and the taxonomic structure of the benthic macroinvertebrates fauna of water systems (reservoir, fisheries and channels) of the CEPTA/IBAMA (Pirassununga, SP), a study with two types of methodologies was carried out. The samples of the sediment in the reservoir had been carried out with the Ekman-Birge grab, and in the fisheries and the channels with artificial substrate. The assemblages of benthic macroinvertebrates had been analyzed taxonomic and structurally. The larvae of Chironomidae (Diptera) were the main organisms in all the environments. The predominance of Procladius sp. and Djalmabatista pulcher was observed in the two reservoirs. The spatial analysis of the taxa distribution in the depths, pointed out with to major variety of taxa in the less depth regions (< 2m) in the Represa Velha, in contrast of the Represa Nova. At the same time, the average densities of the organisms had been opposing in the two reservoirs, presenting respectively major and lesser values in the intermediate depths (>2<3m). Temporaly, major abundance of macroinvertebrates at the dry season was observed, where major number of individuals occurred, represented mainly for the Procladius sp. and D. pulcher. In the faunistic analysis with artificial substrate, Goeldichironomus maculatus was dominant. There was taxonomic similarity between the assemblages in the artificial substrates in the reservoirs, fisheries and channels. The cluster analysis between the sampling methods, clustering the fauna of the baskets with the artificial substrate in the two reservoirs, and the fauna collected with the Ekman-Birge grab. This result points out with respect to the problematic use of artificial substrate use as a tool to characterize the fauna of a system.Com o objetivo de verificar a distribuição e a estrutura taxonômica da fauna de macroinvertebrados bentônicos dos corpos d água (represas, viveiros e canais) do CEPTA/IBAMA (Pirassununga, SP.) foi realizado um estudo com dois tipos de metodologias. As amostras do sedimento nas represas foram obtidas com o auxílio de draga tipo-Ekman-Birge e as dos viveiros e canais, com utilização de substrato artificial tipo cestos. A fauna de macroinvertebrados bentônicos foi analisada taxonômica e estruturalmente. As larvas de Chironomidae (Diptera) foram os principais componentes em todos os ambientes, entre elas, observou-se o predomínio de Procladius sp. e Djalmabatista pulcher nas represas A análise espacial da distribuição dos táxons por faixas de profundidades apontou para maior variedade de táxons nas regiões menos profundas (x < 2m) na Represa Velha, ao contrário da Represa Nova. Da mesma forma, as densidades numéricas médias foram opostas nas duas represas, apresentando respectivamente valores maiores e menores nas profundidades intermediárias (2 > x < 3m). Temporalmente, foi observado maior abundância de macroinvertebrados nas épocas de estiagem onde ocorreu maior número de indivíduos, representados principalmente pelos dois táxons dominantes Procladius sp. e D. pulcher. Na análise faunística com substrato artificial Goeldichironomus maculatus foi dominante em todos os substratos artificiais. Houve elevada similaridade taxonômica entre as faunas presentes nos substratos artificiais introduzidos nas represas, viveiros e canais. A análise de agrupamento comparativa entre os métodos de amostragem reuniu a fauna dos cestos com substratos artificiais nas duas represas em um grupo e a fauna coletada com draga em um outro grupo. A fauna de macroinvertebrados dos diversos locais estudados não apresentou arranjos estruturais diferenciados segundo os diferentes usos dos sistemas

Cryptochironomus brasiliensis Silva, Strixino & Oliveira, 2010, sp. n.

Cryptochironomus brasiliensis sp. n. (Figs. 1–12) Type material. Holotype male with larval and pupal exuviae, BRAZIL: São Paulo State, São Carlos, Monjolinho stream, 29 /vii/ 2009, F. L. Silva & S. Trivinho-Strixino. Paratypes: 1 female with pupal and larval exuviae, as holotype. 2 males with pupal exuviae, as holotype except for Mayaca pond, 2 /xii/ 2000, S. Trivinho-Strixino. 1 male with pupal exuviae, as previous except for 9 /xii/ 2000. Etymology. This species is named after the country from which it was collected using the Latin spelling of Brazil. Diagnostic characters. Cryptochironomus brasiliensis differs from other Cryptochironomus species by combination of the following characters. Adult male: hypopygium with broader superior volsella, with 3 long setae apically; inferior volsella stout, completely covered by superior volsella, with 3 long setae. Pupa: abdomen distinctly reticulate on T I–VI; faint reticulation on T VII–VIII; anal lobe with 117–146 filaments. Larva: head capsule length of about 492–531 μm, AR 0.80–1.05. Description. Male (n = 4 unless otherwise stated) Dimensions. Total length [6.3] 4.61–6.29, 5.25 mm (3). Wing length [2.45] 2.27–2.45, 2.36 mm. Total length/wing length [2.57] 1.96–2.57, 2.22 (3). 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. Legs dark brown with medium third of femur, tibia and half proximal of Ta 1 pale brown. Abdomen including hypopygium brown. Head. Eyes ratio [0.82] 0.77–1.06, 0.88 (3). Flagellum [1172] 1172 –1328, 1287 μm long; AR [2.06] 2.06– 2.78, 2.50. Palpomeres 1–5 lengths (in μm): [49] 49–51 (2); [84] 75–84 (2); [253] 231–253 (2); [190] 153– 190 (2); [271] 202–271 (2). Frontal tubercles [31] 20 –31, 27 (3) μm long, [16] 8 –16, 12 (3) μm wide. Temporal setae 27–30 (2), irregularly biserial. Clypeus with [21] 18–21, (3) setae. Thorax. Antepronotum with [14] 14 (1) setae. Acrostichals [22] 22 (1), biserial, beginning near antepronotum; dorsocentrals [14] 14 (1), partly biserial; prealars [5] 5 (1); supraalar [1] 1 (1). Scutellum with [21] 21 (1) biserial setae. Scutal tubercle present. Wing [0.71] 0.65–0.71, 0.68 mm wide. Membrane without setae. Brachiolum with [2] 2 setae; R with [23] 22–24 setae; R 1 with [18] 18–22 setae; R 4 + 5 with [25] 25–33 setae. Squama fringed. R 2 + 3 ending close to, but distinctly separate from R 1. VR = [1.09] 1.02–1.10, 1.08. Legs. Mid leg with two pseudospurs on Ta 1–4. Tarsal claws on all legs slender and hook-like, pulvilli well developed. Lengths and proportions of legs as in Table 1. Hypopygium (Figs. 7–8). Tergite IX with [13] 13–16 (2) strong setae. Anal point slender, apex wider than base, [108] 108–137, 118 μm long. Superior volsella broad, with [3] 3 (1) long setae apically. Inferior volsella stout, completely covered by superior volsella, with [3] 3 (1) long setae (Fig. 8). Gonostylus short about [2.17] 1.87–2.90, 2.40 times as long as wide. HR [0.78] 0.75–1.03, 0.88. Pupa (n = 4 unless otherwise stated) Dimension. Abdomen [5.6] 4.5–5.6, 4.9 mm long. Coloration. Exuviae pale brown. Cephalothorax (Figs. 1–3). Cephalic tubercles [114] 86–134, 106 μm long, conical, apically pointed; frontal setae [45] 24 –45, 36 μm long, placed subapically (Fig. 1). Wing sheath [1.41] 1.37–1.41, 1.38 mm long. Thorax extensively granulose (Fig. 2); scutal tubercle present; prealar tubercle absent; antepronotals 2 (3), precorneals 2, dorsocentrals 4. Basal ring constricted medially (Fig. 3). Abdomen (Figs. 4–6). Shagreenation on T I–VI covering most of tergite, with fine reticulations; T VII and anal lobe finely reticulate (Fig. 6 d) 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. 4, 6a); spines on 4 th and 8 th segments as figures 6 b and 6 c, respectively. T II–VIII and S I–V with posterior row of spines; S VI–VIII with few spines (Fig. 4). S I with anterolateral shagreen patches (Fig. 5). Pedes spurii B present on segment II. Pedes spurii A present in segment IV, reduced to few spinules. Abdominal chaetotaxy as in Table 2. Anal lobe with complete fringe of about [134] 117–146 taeniae. 4 th instar larva (n = 2 unless otherwise stated) Coloration. Body reddish; head yellowish, postmentum and frontoclypeus without dark areas. Procercus and anal setae pale brown. Posterior parapod claws all pale yellowish. Head [531] 492–531 μm long, [453] 422–453 μm wide. Antenna (Fig. 9) [145] 145–176 μm long, with 5 segments, basal antennal segment [65] 65–80 μm long, with ring organ [41] 41–50 μm from base. AR [0.80] 0.80–1.05. Antennal blade [39] 39–45, arising in distal 1 / 3 of segment 2, reaching almost antennal apex. Style present on segment 2. Maxilla. Basal palp segment [47] 47–59 μm long, [14] 14–18 μm wide, with ring organ [6] 6– 12 μm from base. Labrum (Fig. 10). SI short, blade-like; SII longer, more robust blade-like, [57] 51–57 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 11) [110] 108–110 μm long with apical tooth and 2 inner triangular teeth dark brown. Seta subdentalis slender, base wider than apex. Mentum (Fig 12). With a large middle white tooth and 5 dark lateral teeth; outermost notched. Ventromental plate about [1.25] 1.23–1.25 times as wide as width mentum, course striated. Abdomen. Procercus [0.84] 0.74–0.84 times as long as width, with 7 anal setae. Posterior parapod with simple claws. FIGURES 1–6. Cryptochironomus brasiliensis sp. n., pupa. 1. Cephalic tubercles. 2. Thorax. 3. Basal ring. 4. Abdomen. 5. Sternite I. 6. Armature and reticulation on abdominal segments: a. hook on 2 nd segment, b. spines on 4 th segment, c. spines on 8 th segment, d. reticulation on 4 th segment. Remarks. The male of C. brasiliensis can separated from C. imitans Saether based on shape of inferior volsella, broader with 3 setae in C. brasiliensis, instead of 1–2 setae as in C. imitans. The pupae of C. digitatus Malloch, C. sorex Townes and C. imitans Saether are the most similar to pupa of C. brasiliensis apart from abdomen and cephalic tubercle lengths and the number of anal lobe filaments. The larvae of C. brasiliensis seem to be closely related to C. conus Mason and C. imitans Saether except for the length of the second antennal segment. The larvae of C. brasiliensis are relatively common on aquatic system from southeast Brazil and were collected on sandy in bottom of streams and ponds.Published as part of Silva, Fabio Laurindo Da, Strixino, Susana Trivinho & Oliveira, Heliana Rosely Neves, 2010, New species of Cryptochironomus Kieffer, 1918 (Diptera: Chironomidae: Chironominae) from Brazil, pp. 18-32 in Zootaxa 2614 on pages 19-23, DOI: 10.5281/zenodo.19787

Cryptochironomus Kieffer

Cryptochironomus Kieffer Cryptochironomus Kieffer, 1918: 46. Type species. Chironomus supplicans Meigen, 1830 (= chlorolobus Kieffer, 1918). Generic diagnosis (emended). Based on the Brazilian species, the generic description of Cryptochironomus to male (Cranston et al. 1989), pupa (Pinder & Reiss 1986) and larva (Pinder & Reiss 1983) can be emended as follows: male with inferior volsella partially (C. mantiqueira sp. n.) or completely (C. brasiliensis sp. n. and C. reshchikovi sp. n.) covered by superior volsella. Pupa with scutal tubercle and prealar tubercle present or absent; tergites II–IV with 2–3 fine L setae. Larva with antenna with 5 or 6 segments.Published as part of Silva, Fabio Laurindo Da, Strixino, Susana Trivinho & Oliveira, Heliana Rosely Neves, 2010, New species of Cryptochironomus Kieffer, 1918 (Diptera: Chironomidae: Chironominae) from Brazil, pp. 18-32 in Zootaxa 2614 on page 19, DOI: 10.5281/zenodo.19787

Cryptochironomus mantiqueira Silva, Strixino & Oliveira, 2010, sp. n.

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 2 nd segment, b. spines on 4 th segment, c. spines on 7 th segment. Wing 0.68 mm wide. Membrane without setae. Brachiolum with 2 setae; R with 20 setae; R 1 with 12 setae; R 4 + 5 with 16 setae. Squama fringed. R 2 + 3 ending close to, but distinctly separate from R 1. VR = 1.06. Legs. Mid leg with two pseudospurs on Ta 1–4. Tarsal claws on fore leg slender and hook-like, pulvilli well developed. Lengths and proportions of legs as in Table 3. fe ti ta 1 ta 2 ta 3 ta 4 ta 5 LR BV SV p 1 1046 1108 – – – – – – – – p 2 1123 1138 769 369 307 169 123 0.68 3.13 2.94 p 3 923 831 – – – – – – – – 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 4 th and 7 th segments as in figures 18 b and 18 c, 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. 4 th 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.Published as part of Silva, Fabio Laurindo Da, Strixino, Susana Trivinho & Oliveira, Heliana Rosely Neves, 2010, New species of Cryptochironomus Kieffer, 1918 (Diptera: Chironomidae: Chironominae) from Brazil, pp. 18-32 in Zootaxa 2614 on pages 23-26, DOI: 10.5281/zenodo.19787