Sturmius panamaensis Castaño-Meneses & Palacios-Vargas, 2011, sp. nov.
Creators: name: Castaño-Meneses, Gabriela
name: Palacios-Vargas, José G.
Publisher: name: Zenodo
Year: 2011
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Entognatha
Collembola
Sturmiidae
Sturmius
Sturmius panamaensis

description: Sturmius panamaensis sp. nov.
(Figs. 1–12)
Type locality. Panamá, Colón, San Lorenzo Forest.
Type material. HOLOTYPE: female, deposited at Ecología y Sistemática de Microatrópodos Collection (LESM) at Sciences Faculty, Universidad Nacional Autónoma de México. PARATYPES: 4 female paratypes, 2 preadult female paratypes, 5 male paratypes. All type material on slides. One female and one male deposited at Senckenberg Museum für Naturkunde, Görlitz, Germany; one female and one male deposited at Museo de Invertebrados G.B. Fairchild, Universidad de Panamá (MIUP); two females, two preadult females and three males deposited at Ecología y Sistemática de Microatrópodos Collection (LESM) at Sciences Faculty, Universidad Nacional Autónoma de México. All type material from: Panamá, Colón, San Lorenzo Forest (9o 17’N, 79o 58’W) canopy debris in tropical rainforest at 130 m asl, 8-X-2003. N. Winchester & K. Jordan leg. Additional material, more than 300 specimens are kept in alcohol at Ecología y Sistemática de Microatrópodos Collection (LESM) at Sciences Faculty, Universidad Nacional Autónoma de México.
The following description of Sturmius panamaensis sp. nov. applies to both sexes if not otherwise stated.
Measurements. Total female length up to 0.60 mm (N=7), male length 0.45 mm (N=5), juvenile 0.39 mm (N=10); female head diameter 0.21 mm (0.18–0.21), male 0.16 mm (0.15–0.16), juvenile 0.15 mm (0.11–0.25); female mucro 66 Μm (50–82), male 57 Μm (50–58), juvenile 41 Μm (27.5–42); female appendices anales 82 Μm (62.5–100).
Proportions. Whole antenna: head length ratio = 1.73 (1.58–1.90) in females, 1.53 (1.59–1.90) in males, and 1.48 in juveniles (1.17–1.67). Ant. I: II; III; IV ratio = 1: 1.68 (1.0–2.5); 2.75 (1.75–4.5); 6.85 (4.38–11.0) in females, 1: 1.31 (1.0–1.8); 2.09 (1.71–3.0); 4.94 (3.28–7.0) in males, and 1: 1.39 (1.0–1.75); 2.06 (1.5–2.75); 4.87 (1.96–6.75) in juveniles. Ant. IV distal part: proximal part ratio = 2.6 (2.3–3.4). Mucro: dens; manubrium ratio = 1: 1.52 (1.25–1.8); 1.37 (1.2–1.6) in females, 1: 1.48 (1.28–1.77); 1.27 (0.91–1.51) in males, and 1: 1.49 (0.81–1.8); 1.42 (0.75–1.8) in juveniles. Appendices anales: unguis III inner edge ratio = 2.7 (2.5–3.09). Mucro: unguis III inner edge ratio = 2.5 (1.78–3.25) in females; 2.64 (2.25–3.05) in males, and 2.51 (1.56–3.75) in juveniles. Mucro: appendices anales ratio = 0.89 (0.71–1.07).
Pigmentation. Eye-patches deep black. General colour of the females and males dark blue-purple. Cuticle forming hexagonal patterns of primary granules and secondary granules with triangular tip, similar to Actaletes or Sphaeridia (Bretfeld, 1994).
Head. Eye-patches protruding with 8 + 8 ommatidia (Fig. 2). Smallest ommatidium is E. Ant. I with 7 setae, Ant. II with 12 setae, and Ant. III with 17 setae and a simple papilla (Fig. 4); Ant. III sensory organ with two sensilla concealed in one cavity, separated by a short cuticular fold. Ant. IV with 8 whorls of setae but poorly defined subsegments (Fig. 5).
Legs. Precoxa 1on leg I lacking seta. Legs II and III with one seta on precoxa 1; precoxa 2 on legs I–III with 1 seta each. Coxa I–III with 4 setae; trochanter I–III with 4 setae each, femur I, II, III with proximal/medial/distal setae as 2/3/7, 3/3/7, 3/3/6 respectively. Tibiotarsi (Figs. 10, 11, 12) with distal whorls and longitudinal rows of setae. Ungues without pseudonychium. Ungues I–III with small inner tooth; ungues II with thickened setae distally. Only empodial appendage I with a long filament exceeding claw (Figs. 1 A, 10a); empodial appendage II strong, with thick tip but without filament (Figs. 1 B, 11a), empodial appendage III slender without filament (Fig. 12 b). Tibiotarsi with some setae p slightly barbulate as S. truncivivus; oval organs small, obscure.
Abdomen. Form as for genus (Fig. 3). Trichobotrium B shortest. Row 1, 1 + 1 seta; row 2, 3 + 3 setae (rows are indicated with dashed lines in Fig. 3). Most setae fine and straight, 2 + 2 flame-shaped fairly short spines dorsal to trichobothrium A on each side. Ventral trunk setae absent. Furcula base with 10 + 10 setae, seta 3 being a relatively long and thin neosminthuroid seta (Fig. 6). Small abdomen with Abd. V short, protruding into the great abdomen. Abdomen VI as in Figure 6. Trichobothrium D similar to A. Setae sa2 and sa3 similar to the type species. Anal appendices (a5) similar to the type species. Males with 15 setae on the genital plate (Fig. 7).
Ventral tube. As characteristic for the genus with 1 + 1 anterior distal setae. Retinaculum with one seta on corpus, each rami with one basal appendix and 3 + 3 apical teeth, posterior lobe small (Fig. 9). Manubrium (Fig. 8) with 5 + 5 setae, seta 1 longer than others. Dens with 8 setae in distal whorl, row J: 1 distal seta, row PE no seta, formula of anterior setae 3 … 1 from distal to basal. Ventral setae on Fig. 8 marked with *. Mucrones relatively long, thin, with both edges serrated (Fig. 8).
Derivatio nominis. From Panama, the country locality of the new species.
Discussion. Sturmius panamaensis sp. nov. is similar to the two other known species of Sturmius, but it has a shorter mucro, the spines dorsal to trichobothrium A are not so short as in the other species and are flame shaped, trichobothrium B in the new species is smaller than A and C. Also only empodial appendix I has a long filament (similar to the other two species), but the ungues II and III lack filaments, which are present in the two other species of the genus. The anal appendices of the female are longer than in other species, which affects the ratio ungues/ mucro as it is the smallest (see Table 1). Setae ai and i of tibiotarsus III of the new species are barbed, and not smooth as in the type species. The anal appendices (a5) are more similar in shape to the type species S. epiphytus. In the new species the neosminthuroid seta is long and thin, while in S. epiphytus it is short and thick. S. panamaensis sp. nov. lacks a pseudonychium on all the ungues, unlike the type species and S. truncivivus.
anales Ant: I:II;III;IV
Total (mm) Head (mm) Mucro (µm)
f m f m f m f m f m Ratios
Manubrium: Dens: mucro Anal spines: Ungues III Mucro: Append. Anales: Mucro
Ungues III
f m f f f
S. epiphytus 1:1.4; 1.5 1:1.5; 1.5 1.4 2.8 0.5
S. truncivivus 1:1.6; 1.6 1:1.7; 1.7 1.6 3.3 0.5
S. panamaensis 1:1.5; 1.3 1:1.4; 1.2 2.7 2.5 0.9
Ecological notes. The new species was collected during September and October (rainy season) of 2003, in the canopy of several species of trees: Brosimum utile (Kunth) Oken, Luehea seemannii Planch. & Triana, Vochysia ferruginea Mart., Ficus tonduzii Standl., Calophyllum longifolium Willd., Anacardium excelsum Skeels, Pourouma bicolor Mart., Trichilia tuberculata C. D.C. and Terminalia amazonia (Gmel.) Exell. A total of 405 specimens were collected, all of them were found by extracting suspended debris from the canopy in Berlese funnels at eight sites in the San Lorenzo forest in the Atlantic coast of Panama. The height of the sampling sites were 10 to 29 m from the base of the trees. The average (±SD) of fresh weight of the samples was 59.96 ±23.5 gm (N=8), and the dry weight average was 20.76 ±7.75 gm. The mean humidity content in the samples was 65%. The canopy was, on average, 6.88% open.
The genus Sturmius was previously only known from South America (Colombia and Brazil), and this is the first record for Central America. Canopy sampling in Mexico (Chiapas, Hidalgo and Jalisco States), has not collected this genus (Palacios-Vargas & Castaño-Meneses 2003). Forest canopies in Costa Rica, El Salvador and Nicaragua need to be sampled in order to establish the northern limits for the genus.
Although there are important faunal differences in springtails assemblages, according to vegetation type, the species richness of canopy Collembola is low compared with that of soil and litter of the same area (Palacios-Vargas & Castaño-Meneses 2003; Palacios-Vargas & Gómez-Anaya 1993). Nevertheless some species can be abundant and make this group of canopy arthropods among the most abundant. The relevant families are Paronellidae, Entomobyridae and Bourletiellidae (Greenslade & Sutrisno 1994; Guilbert 1997; Guilbert et al. 1995; Palacios- Vargas & González 1995; Palacios-Vargas et al. 1998; Rodgers & Kitching 2011). All the members of the family Sturmiidae are have been found only in epiphytic environments. Some genera such as Deuterosminthurus, Willowsia, Salina and even Americanura, have representatives in soil, litter and the canopy, but not Sturmius, which has never been found in soil or litter.
description: Published as part of Castaño-Meneses, Gabriela & Palacios-Vargas, José G., 2011, A new species of the family Sturmiidae (Collembola: Symphypleona) from Panama, pp. 59-66 in Zootaxa 2923 on pages 60-65, DOI: 10.5281/zenodo.205556