Research Article |
Corresponding author: Lucia M. Almeida ( lalmeida51@gmail.com ) Academic editor: Janakiraman Poorani
© 2020 Alexandra Magro, Julissa Churata-Salcedo, Emilie Lecompte, Jean-Louis Hemptinne, Lucia M. Almeida.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Magro A, Churata-Salcedo J, Lecompte E, Hemptinne J-L, Almeida LM (2020) A new species of Nephus (Nephus) (Coleoptera, Coccinellidae) described from Reunion Island. ZooKeys 962: 123-137. https://doi.org/10.3897/zookeys.962.51520
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We report here a new species belonging to Nephus (Nephus) Mulsant. Nephus (Nephus) apolonia sp. nov. was collected in the Reunion Island (Mascarene Archipelago, Indian Ocean). We describe this new species and redescribe and illustrate three other Nephus species already known from Reunion: Nephus (Nephus) oblongosignatus Mulsant, 1850, Nephus (Geminosipho) reunioni (Fürsch, 1974) and Nephus (Nephus) voeltzkowi Weise, 1910. Furthermore, we present a phylogenetic tree for these four species and calculate the genetic distances between them, using high-throughput DNA sequencing of the mitochondrial genome. The similar external morphology of N. apolonia sp. nov. and N. voeltzkowi very probably explains why individuals from the first species have been mistakenly identified as the latter and were not recognized as different until now. Other than external and genitalia traits, the present study provides molecular evidence confirming these are indeed two different species.
Coccinelloidea, ladybird beetle, molecular data, predator, Scymnus, systematics
The Coccinellidae is a diversified family composed of some 6000 species, and the largest of the superfamily Coccinelloidea (
The following characters distinguish Nephus: antennae with nine or pseudo-11 antenomeres; prosternal process sub-quadrangular, as wide as long, with a shallow lateral depression, without carina; legs with tarsi trimerous; abdomen with six ventrites, with incomplete postcoxal line, recurved and not reaching posterior margin of first ventrite.
According to
In this contribution, we describe a fourth Nephus (Nephus) species for Reunion Island, and redescribe the three already known species based on the study of a number of specimens of each species and using molecular data.
The specimens examined here were provided by the first author from a laboratory rearing (Laboratoire Evolution & Diversité Biologique, Université Toulouse III) initiated from field collected material: Nephus oblongosignatus and N. voeltzkowi were collected in Reunion Island in 2011, N. apolonia sp. nov. was collected in Reunion Island in 2013, and N. reunioni was collected in 2007 in Portugal, where the species had been introduced for biological control in the 1980’s (
Photographs of the external morphology as well as male and female genitalia were taken using a Leica DMC 2900 Digital Camera attached to Leica M205C stereomicroscope using Leica Application Suite. Furthermore, specimens were examined with a JEOL JSM-6360LV scanning electron microscope in the Electronic Microscopy Center of Universidade Federal do Paraná. The length and width measurements of the species represent the average of the examined specimens.
The terminology used in the descriptions follows
Examined material is deposited in the following collections: Coleção Entomológica Pe. J.S. Moure, Universidade Federal do Paraná, Curitiba, Paraná, Brazil (
We used the mitochondrial genome of Nephus species previously sequenced by
Molecular characterization and distance analyses were conducted on the cytochrome c oxidase I (COI) gene using MEGA v.7 (
Genbank accession numbers for the mitogenome sequences used in the analysis.
The species of Nephus present the following characteristics: antennae with nine or pseudo-11 antenomeres (Fig.
1 | Each elytron black with one spot | 2 |
1’ | Each elytron black with two spots (Fig. |
Nephus (Geminosipho) reunioni (Fürsch, 1974) |
2 | Body rounded, oblong; each elytron with one yellowish oblong spot (Fig. |
Nephus (Nephus) oblongosignatus Mulsant, 1850 |
2’ | Body elongated, each elytron with one yellowish elongated spot | 3 |
3 | Each elytron black with one big oval yellowish elongated spot, reaching middle of elytron; spermatheca with sharp base and truncated apex (Fig. |
Nephus (Nephus) voeltzkowi Weise, 1910 |
3’ | Each elytron black with one small irregular yellowish spot, not reaching middle of elytron; spermatheca with sharp base and truncated apex (Fig. |
Nephus (Nephus) apolonia Magro & Almeida, sp. nov. |
Scymnus oblongosignatus Mulsant, 1850: 960 (original description).
Nephus oblongosignatus:
Nephus grinerae
Sicard, 1909: 145 (original description);
Scymnus (Nephus) oblongosignatus:
Nephus (Nephus) oblongosignatus:
Nephus oblongosignatus is similar to N. voeltzkowi and N. apolonia sp. nov. but differs in the body shape, size and shape of the spots and the pattern of genitalia.
Male. Length 1.77 mm, width 1.28 mm. Body oval, oblong, with short fine whitish pubescence. Integument of pronotum, scutellar shield and elytra black (Fig.
Scanning electron microscopy A–D antennae E–H prosternal process I–L tarsi M–P abdominal postcoxal line A, E, I, M Nephus (Nephus) oblongosignatus Mulsant, 1850 B, F, J, N Nephus (Geminosipho) reunioni (Fürsch, 1974) C, G, K, O Nephus (Nephus) voeltzkowi Weise, 1910 D, H, L, P Nephus apolonia Magro & Almeida, sp. nov.
Genitalia with tegmen, penis guide, phallobase and parameres symmetrical. Spicule long (Fig.
Female. Length 1.79 mm, width 1.34 mm. Similar to male. Genitalia with coxites longer than wide, subtriangular, 3.0× longer than wide; stylus mamiliform with long bristles (Fig.
Reunion Island: First generation from a laboratory rearing (Laboratoire Evolution & Diversité Biologique, Université Toulouse III) initiated from field material collected in November 2011 in Manapany-les-Bains, 19 specimens [
Scymnus (Nephus) reunioni Fürsch, 1974: 275 (original description).
Nephus (Sidis) reunioni
Nephus (Geminosipho) reunioni:
Nephus reunioni differs from the other species in the number, shape and size of the spots and the pattern of genitalia.
Male. Length 1.7 mm, width 1.28 mm. Body oval, with short fine whitish pubescence. Integument of pronotum, scutellar shield and elytra black (Fig.
Genitalia with tegmen, penis guide, phallobase and parameres symmetrical. Penis guide narrow, longer than parameres, sharp at apex. Parameres articulated with phallobase, distant from each other, strongly widened at apex, with long bristles along parameres (Fig.
Female. Length 1.75 mm, width 1.30 mm. Similar to male. Genitalia with coxites longer than wide, subtriangular, 3.0× longer than wide; stylus mamiliform with short bristles (Fig.
Portugal: Specimens from a laboratory rearing (Laboratoire Evolution & Diversité Biologique, Université Toulouse III) initiated from field material collected in 2007 in Cascais, 10 specimens [
It should be noted that
Nephus (Nephus) voeltzkowi
Weise, 1910: 512 (original description);
Nephus seychellensis
Sicard, 1912: 362 (original description);
Scymnus (Nephus) voeltzkowi:
Nephus (Nephus) voeltzkowi:
Nephus voeltzkowi resembles N. oblongosignatus and N. apolonia in the color of the integument and spots but differs in the shape and size of the spots and the female genitalia.
Female. Length 1.65 mm, width 1.10 mm. Body oval, with short fine whitish pubescence. Integument of pronotum, scutellar shield and elytra black. Elytra with one yellowish big oval spot on each elytron; elytra apex yellowish (Fig.
Genitalia. Coxites longer than wide, subtriangular, 3.0 x longer than wide; stylus mamiliform with long bristles (Fig.
Male genitalia according to
Reunion Island: Specimens from a laboratory rearing (Laboratoire Evolution & Diversité Biologique, Université Toulouse III) initiated from field material collected in November 2011 in Manapany-les-Bains, 14 specimens [
It should be noted that only female specimens of N. voeltzkowi were observed here. Furthermore, although
Nephus apolonia sp. nov. is similar to N. voeltzkowi and N. oblongosignatus but differs by the size and shape of the spots and the pattern of genitalia.
Male. Length 1.69 mm, width 1.2 mm. Body oval, oblong, with short fine whitish pubescence. Integument of pronotum, scutellar shield and elytra black. Elytra with one yellowish longitudinal spot on each elytron (Fig.
Genitalia with tegmen, penis guide, phallobase and parameres symmetrical. Penis guide shorter than parameres, sharp at apex (Fig.
Female. Length 1.88 mm, width 1.30 mm. Similar to male. Genitalia with coxites longer than wide, subtriangular, 3.0× longer than wide; stylus mamiliform with long bristles (Fig.
This species is named after an early name of Reunion Island, mentioned as “Santa Apolonia” on the Portolan charts (nautical charts) from the XVIth century (GENUNG, 2017).
Reunion Island: from a laboratory rearing (Laboratoire Evolution & Diversité Biologique, Université Toulouse III) initiated from field material collected in December 2013 in Manapany-les-Bains and Étang-Salé.
Holotype
male, pinned, with genitalia in a separate microvial. Original label: “Reunion Island, 1 specimen [MNHN]”; “HOLOTYPE/ Nephus apolonia Magro and Almeida” [red label]. Paratypes. The following specimens are designated as paratypes with labels: “same data as for holotype”. “PARATYPE/ Nephus apolonia Magro and Almeida” [yellow label]: “Reunion Island, 2 specimens [MNHN,
Reunion Island: L’Étang-Salé, Le Trou d’eau (21°16'54.2"S, 55°21'39.7"E); Saint-Denis, Saint-Bernard (20°52'58.36"S, 55°23'50.19"E); Saint-Louis, Etang du Gol (21°17'20.9"S, 55°23'16.1"E); La Possession, Ravine à Malheur (20°54'03.5"S, 55°22'32.1"E); Saint-Pierre, CIRAD (21°19'13.8"S, 55°29'6"E); L’Étang-Salé, ARDA (21°17'05.6"S, 55°22'38.1"E) and Saint-Joseph, Langevin (21°22'53.4"S, 55°38'48.4"E).
Nephus apolonia sp. nov. has apparently been misidentified as N. voeltzkowi until now. We verified that this was the case for specimens captured by the Insectarium de La Réunion.
The mitochondrial genome of one specimen of Nephus apolonia is deposited in Genbank under accession number MN164644. Genetic distances based on the COI sequences between N. apolonia and other Nephus species confirm that N. apolonia is different from the other species, as all distances are within the same range (i.e., 0.13–0.17) (Table
Pairwise Kimura-2-parameter distances for the mitochondrial COI gene for the Nephus species.
1 | 2 | 3 | 4 | ||
1 | Nephus apolonia | ||||
2 | N. reunioni | 0.131 | |||
3 | N. includens | 0.133 | 0.126 | ||
4 | N. voeltzkowi | 0.174 | 0.170 | 0.160 | |
5 | N. oblongosignatus | 0.155 | 0.150 | 0.142 | 0.172 |
Maximum likelihood phylogeny of Nephus (Nephus) apolonia Magro & Almeida, sp. nov. and four related species based on the mitochondrial genome (without the control region) reconstructed through 1000 non-parametric bootstrap replicates. The scale bar indicates 0.04 substitutions per site. Numbers on major nodes represent Maximum Likelihood bootstrap support.
We are extremely grateful to our late colleague and friend, Serge Quilici (CIRAD, St Pierre) for his logistic support during AM visits to Reunion and more than everything for his kindness. We also would like to thank J. Rochat for access to samples from the Insectarium de La Réunion, and the Electronic Microscopy Center (UFPR) for the pictures. This study was supported by the CAPES Program “Sciences without borders” (401366/2014-6), PhD fellowship to JMCS (1578651/2016) and CNPq for the research fellowship to LMA (308992/2017-2) Brazil. Furthermore, AM, EL, and JLH were supported by the “Laboratoires d’Excellence” LabEx TULIP (ANR-10-LABX-41) and CEBA (ANR-10-LABX-25-01).