Gumilla adspersus, Navas, 1912, Navas, 1912

Rosa Lara, Rogéria Inês, Perioto, Nelson Wanderley & Martins, Caleb Califre, 2024, Osmylidae (Insecta: Neuroptera) from Atlantic rainforest in southeastern Brazil and new records for Gumilla adspersus Navás, 1912, Revista Chilena de Entomología (Rev. Chil. Entomol.) 50 (1), pp. 41-50 : 43-47

Results and Discussion

A total of 76 adults of lance lacewings were obtained in this study ( Tab. 1 ), among which 73 specimens of I. pulverulentus (Gerstaecker, 1894) (96.1% of the total collected) ( Fig. 1A ), one of Isostenosmylus sp. (1.3%) which is probably a new species, and two of G. adspersus Navás, 1912 (2.6%) ( Fig. 1B ).

The osmylids were more frequently observed in the PESM/NSV (59.2% of the total collected), PEI (30.3%), and PEMD (7.9%), inland collection sites in the state of São Paulo, with altitudes of 1,030 m, 880 m and 350 m above sea level (asl), respectively. Only 2.6% of the Osmylidae obtained were sampled at EEJI ( 16 m asl) and no specimens were collected at PESM/NP ( 215 m asl), areas located near the marine coast ( Tab. 1 , Fig. 2 ).

Isostenosmylus pulverulentus , the most abundant species captured, was recorded at PESM/ NSV, PEMD and PEI, with highest abundances recorded in late summer and early autumn (57.5% of the total collected) and mid-spring (20.6% of the total collected). In this study, the presence of I. pulverulentus was restricted to environments with altitudes between 350 and 1,030 m asl. The geographical distribution of I. pulverulentus is limited to higher areas in the South and Southeast of Brazil and Paraguay ( Martins et al. 2019; Machado and Martins 2022). In Brazil, this species has been recorded in Atlantic rainforest areas in the states of Minas Gerais, EspÍrito Santo, Rio de Janeiro, São Paulo, Paraná, Santa Catarina and Rio Grande do Sul, at altitudes ranging from 867 to 2,172 m asl. ( Martins et al. 2016, 2018, 2019; Schuster and Machado 2021; Machado and Martins 2023). The results of this study are in accordance with those of the authors mentioned before, as the highest incidence of I. pulverulentus was observed in areas with an altitude range between 880 to 1,030 m asl. The data obtained allowed to expand the knowledge about the temporal variation of this species, which was captured mainly between November and May, the hottest and wettest months of the year.

A single specimen of Isostenosmylus sp. was captured at PESM/NSV ( 1,030 m asl), in July, winter in the Southern hemisphere.

The two specimens of G. adspersus studied were caught in areas of Atlantic rainforest located close to the marine coast: a specimen at the EEJI ( 16 m asl) in mid-winter and another from the register of Rogério Dias on the iNaturalist website ( Fig. 3A ) for Rio de Janeiro (~ 550 m asl) in late autumn. Up to date, the geographical distribution of this species was limited to its type locality, the municipality of Blumenau ( 21 m asl), in the state of Santa Catarina, Brazil. About 110 years after its description by Navás (1912), these new records extend the geographical distribution of G. adspersus to the municipality of Iguape (state of São Paulo) and Rio de Janeiro (state of Rio de Janeiro), about 300 and 720 km to the northeast of the type locality, respectively ( Fig. 3B ). Based on the two records from São Paulo and Rio de Janeiro states, it can be inferred that this species is probably distributed in low altitude areas of the Atlantic rainforest.

This is the second long-term study in Brazil that investigates the fauna of Osmylidae in Atlantic rainforest areas. Schuster and Machado (2021), in their study on Neuroptera fauna in Atlantic rainforest areas in the state of Paraná, found only four specimens of I. pulverulentus . The use of different capture methods, such as Malaise traps in this study and light traps in Schuster and Machado (2021), was one of the factors that certainly contributed to the large difference in the amount of Osmylidae captured in the two studies. Different authors ( Szentkirályi 1992, 1997; Ábrahám et al. 2003; Lara et al. 2008; Oliveira et al. 2013; Martins et al. 2019; Sarmiento-Cordero et al. 2021) studied Neuroptera sampling and concluded that, for certain groups, it is necessary to combine greater and longer sampling efforts with the use of different types of traps. Despite the difficulty in quantifying its importance, the climate of the studied locations should also be taken into account when dealing with the difference in the amount of osmylids captured in these two studies. In the localities studied by Schuster and Machado (2021) in the state of Paraná predominate the climatic types Cfa (temperate climate, no dry season and hot summer) and Cfb (temperate climate, no dry season and cold summer) while in the localities sampled in the present study predominate the types Af (tropical equatorial), Am (tropical Monsoon) and Cfa, especially in the São Paulo state (Climate-Data.Org. 2023). Thus, the results obtained here are hardly compared due to methodological differences.

Gaps in knowledge about the bioecology of osmylids can be attributed to the lack of studies on their diversity, abundance and seasonality. Long-term investigations, using different types of traps in different biomes can contribute to a better understanding of their bioecology and distribution. The new record of G. adspersus to Rio de Janeiro state based on iNaturalist, is yet another example of the importance of citizen science for understanding Brazilian biodiversity, even rare species as in this case.

Figures

Figure 2. Population fluctuation of Osmylidae (Neuroptera) collected with Malaise traps in five areas of Atlantic rainforest of São Paulo state, Brazil, between October 2009 and December 2011. / Figura 2. Fluctuación poblacional de Osmylidae (Neuroptera) recolectada con trampas Malaise en cinco áreas de la selva atlántica del estado de São Paulo, Brasil, entre octubre de 2009 y diciembre de 2011. EEJI = Estação Ecológica Juréia-Itatins, PEI = Parque Estadual Intervales, PEMD = Parque Estadual Morro do Diabo and PESM/NSV = Parque Estadual da Serra do Mar - Núcleo Santa VirgÍnia.

Figure 3. A. Gumilla adspersus Navás, 1912 (Neuroptera, Osmylidae), habitus dorsal (photo by Rogério Dias on the iNaturalist website). B. Distribution map of Isostenosmylus pulverulentus (Gerstaecker, 1894) and Gumilla adspersus Navás, 1912. (Neuroptera: Osmylidae) and their occurrence records to South America. /Figura 3. A. Gumilla adspersus Navás, 1912 (Neuroptera, Osmylidae), habitus dorsal (foto de Rogério Días en el sitio iNaturalist). B. Mapa de distribución de Isostenosmylus pulverulentus (Gerstaecker, 1894) y Gumilla adspersus Navás, 1912 (Neuroptera: Osmylidae) y sus registros de presencia en Sudamérica.

Figure1.Dorsal habitus of the studied Osmylidae(Neuroptera) species.A. Isostenosmylus pulverulentus (Gerstaecker, 1894). B. Gumilla adspersus Navás, 1912. / Figura 1. Habito dorsal de las especies de Osmylidae (Neuroptera) estudiadas. A. Isostenosmylus pulverulentus (Gerstaecker, 1894). B. Gumilla adspersus Navás, 1912.

Tables

Table 1. Monthly abundance of the Osmylidae (Neuroptera) collected with Malaise traps in five areas of Atlantic rainforest at São Paulo State, Brazil, between October 2009 and December 2011. / Table 1. Abundancia mensual de Osmylidae (Neuroptera) recolectada con trampas Malaise en cinco áreas de la selva atlántica en el estado de São Paulo, Brasil, entre octubre de 2009 y diciembre de 2011.

Month-year	PESM/NSV	PEI	PEMD	EEJI	PESM/NP	Total
	I. pulverulentus Isostenosmylus sp.	I. pulverulentus	I. pulverulentus	G. adspersus	Osmylidae
Oct-09	- -	2	-	0	-	2
Nov-09	14 0	0	0	0	0	14
Dec-09	1 0	0	0	0	0	1
Jan-10	4 0	0	0	0	0	4
Feb-10	2 0	0	0	0	0	2
Mar-10	9 0	5	0	0	0	14
Apr-10	6 0	8	2	0	0	16
May-10	0 0	5	4	0	0	9
Jun-10	0 0	0	0	0	0	0
Jul-10	0 1	0	0	0	0	1
Aug-10	1 0	0	0	2	0	3
Sep-10	0 0	0	0	0	0	0
Oct-10	0 0	1	0	0	0	1
Nov-10	1 0	0	0	0	0	1
Dec-10	0 0	0	0	0	0	0
Jan-11	0 0	1	0	0	-	1
Feb-11	0 0	0	0	0	-	0
Mar-11	0 0	1	-	0	-	1
Apr-11	2 0	-	-	-	-	2
May-11	0 0	-	-	-	-	0
Jun-11	0 0	-	-	-	-	0
Jul-11	0 0	-	-	-	-	0
Aug-11	0 0	-	-	-	-	0
Sep-11	0 0	-	-	-	-	0
Oct-11	2 0	-	-	-	-	2
Nov-11	0 0	-	-	-	-	0
Dec-11	2 0	-	-	-	-	2
Total	44 1	23	6	2	0	76
%	57.9 1.3	30.3	7.9	2.6	0	100.0