Cerrorchestia taboukeli sp. nov., a new terrestrial amphipod (Amphipoda, Talitridae) from Martinique Island

International audienceDuring recent investigations on the terrestrial invertebrates of the tropical rainforest on Martinique Island (Pitons du Carbet), specimens of a new species of the terrestrial amphipod genus Cerrorchestia Lindeman, 1990, C. taboukeli sp. nov., were collected by means of different quantitative and non-quantitative methods (hand collection and Tullgren extraction) in the forest floor. The new species can be easily distinguished from the only other species of the genus, C. hyloraina Lindeman, 1990, by gnathopod 2 (carpus short, palm longer than wide), pereopod 4 dactylus with a denticulate patch, pereopod 5 basis ovate with a deep posterodistal lobe reaching the distal end of the ischium, pleopod 3 ramus with more than six articles. Cerrorchestia tabouleki sp. nov. is the first forest-hopper discovered in the Lesser Antilles, raising the question of island colonization by terrestrial amphipods. Ecological data and a key to terrestrial Talitridae of Central America and the Caribbean islands are provided

A New Species of Freshwater Amphipods Echinogammarus (Amphipoda, Gammaridae) from Algeria

International audienceSeveral samples of amphipods were obtained from six stations in the upper reach of the Youkous Stream, near Hammamet. This study describes a new species, Echinogammarus monodi n.sp., differing from other Echinogammarus species in the length of the first antenna, the setation of the third article of the mandibular palp (bearing three rows of A-setae and two rows of B-setae), the merus and carpus of pereopods 5 with long setae only, and the exopodite of uropod 3 with numerous groups of long simple setae. A full description of the new species and information about its distribution is given in this paper

Cerrorchestia taboukeli Piscart & Ayati & Coulis 2019, sp. nov.

Cerrorchestia taboukeli sp. nov. urn:lsid:zoobank.org:act: 2C82118B-19F6-49F9-90F9-F8D2708943FC Figs 1–5, Table 1 Diagnosis Male Left lacinia mobilis 4-dentate; gnathopods 1 and 2 sexually dimorphic; palm of gnathopod 2 much larger than on gnathopod 1; pellucid lobes on merus, carpus and propodus of gnathopod 1 only. Pereopods 3–7 cuspidactylate. Pereopods 3–4 and telson sexually dimorphic. Female Gnathopod palms equal in size; pellucid lobes on merus, carpus and propodus of gnathopod 2 only. Gnathopod 1 palm subchelate, dactylus long and curved, overreaching the palmar angle. Etymology The epithet taboukeli refers to ‘Taboukéli oüébo’ in the Kalinago language, the pre-Columbian inhabitants of Martinique Island. This term means ‘summit of the mountain’ and refers to the extremely narrow distribution area of the species that is currently known to be restricted to peaks and high plateaus of Pitons du Carbet Mountain Range. Material examined Holotype MARTINIQUE ISLAND • ♂; Fonds St Denis, summit of Piton Boucher, cloud forest; 14°41′56.6″ N, 61°06′08.0″ W; 1059 m a.s.l.; 21 Jul. 2017; collected from leaf litter by hand and using a Tullgren extractor; MNHN-IU- 2019-2276. Paratypes MARTINIQUE ISLAND • 5 ♂♂; same collection data as for holotype; MNHN-IU- 2019-2277 • 5 ♀♀; same collection data as for preceding; MNHN IU- 2019-2278 • 2 ♂♂, 5 ♀♀; same collection data as for preceding; Aug. 2018; collected from leaf litter by hand and using Tullgren extractior; CIRAD-361- 302-P. Other material examined MARTINIQUE ISLAND • ca 25 adult specimens; 2 stations, 14°41′56.6″ N, 61°06′08.0″ W and 14°42′52.6″ N, 61°06′18.0″ W; Jun. 2017 and Aug. 2018; collected on forest floor by hand in the leaf litter of the Carpet Mountain. Description Male Description based on holotype male 11.3 mm. BODY (Fig. 1A). Medium and smooth. HEAD. Eye medium (⅓ head length), round, black. Antenna 1 (Fig. 1B) short, slightly longer than article 4 of antenna 2, flagellum with up to 5 short articles, sparsely setose with robust setae. Antenna 2 (Fig. 1C) less than half body length; peduncular articles slender, article 5 1.3 × longer than article 4; flagellum longer than peduncles with up to 20 articles with robust setae. Upper lip (Fig. 2A) wide, apex rounded and setose. Lower lip (Fig. 2C) without inner lobe; outer lobe very setose with sub-rectangular apical margin. Left mandible (Fig. 2E) incisor 6-dentate, lacinia mobilis 4-dentate, molar triturative, strong. Maxilla 1 (Fig. 2F): inner plate rod-shaped with two terminal robust pappose setae; outer plate with eight terminal serrate setae, palp absent. Maxilla 2 (Fig. 2D): inner plate sub-equal to outer plate in length with 1 large and 1 medium secondary subapical pappose setae; outer plate with 2 setae on outer margin and a row of terminal robust setae. Maxilliped (Fig. 2B): inner plate well developed, 4 × longer than wide, with apical pappose setae and 3 spatule-like spine teeth, inner lateral margin bordered by 4 robust pappose setae; outer plate long, exceeding palp article 1 with apical pappose setae; palp article 2 about as long as wide, inner lobe wide; palp article 3 slightly longer than wide, shorter than palp article 2; palp article 4 minute, dome-shaped, masked by distal setae and setae of palp article 3. PEREON. Gnathopod 1 (Fig. 3A) sexually dimorphic, subchelate; basis slightly expanded posterodistally, 2 proximal facial setae, 3 setae on posterior margin; pellucid lobes on merus, carpus and propodus; carpus longer than propodus, triangular, well developed with posterior carpal lobe posterior margin with long setae; propodus of ‘hammer’ type, expanding distally, inner face with many seta of various length, anterior margin with 3 groups of 1–3 setae and 4 fine setae distally, palm transverse fringed with 6–8 long setae and 5–6 tiny facial setae proximally; dactyl posterior margin with setae only. Gnathopod 2 (Fig. 3B) much larger than gnathopod 1, subchelate, sexually dimorphic; coxa subrectangular slightly longer than wide with a rounded ventral margin; basis expanded posterodistally without setae on anterior margin and 4 small setae on posterior margin; ischium and merus unarmed; carpus triangular, very small and unarmed; propodus ovate, two times as long as wide, inner face with 6–7 small setae, palm transverse fringed with many apical setae of various length; dactylus very long, overreaching the palmar angle. Pereopod 3–7 cuspidactylate. Pereopods 3–4 (Fig. 4 A–B) alike; subequal in length; coxae subquadrate with posterior lobes; merus not expanded, 1.5 × larger and longer than carpus; pereopod 4 propodus longer than carpus, dactylus short with anterodistal denticular patch. Pereopod 5 (Fig. 4E) coxa bilobed; basis ovate with deep posterodistal lobe reaching distal end of ischium, anterior and posterior margin fringed with setae; merus expanded and equal in length to carpus; propodus longer than merus and carpus; dactylus short. Pereopods 6–7 (Fig. 4 F–G) alike, subequal in length, meri and carpi similar in length and propodi longer; dactylus very thin and relatively long. Pereopod 6 coxa bilobed; basis ovate. Pereopod 7 coxa ovate; basis almost round. PLEON. Epimeron 1 widely subtriangular, lacking posterior tooth, without spine on posterior margin. Epimera 2 and 3 subquadrates, posterior distal angles somewhat produced but lacking distinct tooth and without setae of posterior margin (Fig. 5G). Pleopods 1–3 (Fig. 5 H–J) well developed, pleopods 1 and 2 longer than pleopod 3, peduncles well developed 5–6 × longer than wide, 1~3 coupling spines; flagellum biramous, subequal in length; pleopod 1 inner and outer rami with 8 and 10 articles, respectively; pleopod 2 inner ramus with 7 articles, outer with 10 articles; pleopod 3 inner and outer rami very short with 8 articles. Uropod 1 (Fig. 5A) longest; peduncle slender 5 × as long as wide with one row of 5 setae and a strong interramal seta; inner ramus with 4 dorsal marginal setae and few apical robust setae; outer ramus without marginal setae. Uropod 2 wider; peduncle 2 × as long as wide with 3 dorsal marginal setae, 4 marginal or sub-marginal ventral setae smaller, and one apical robust setae; inner ramus with 3 dorsal marginal setae; outer ramus with 5 marginal setae. Uropod 3 peduncle with 2 apical setae dorsally and several very small facial setae, uniramus, ramus slightly arcuate subequal to peduncle in length, not fused to peduncle with 1 dorsal marginal seta and 4 apical setae. Telson (Fig. 5E) weakly longer than wide, weakly cleft, each lobe with 2–3 marginal and 2–3 apical setae. Female Description based on paratype female 9.6 mm. HEAD. Antenna 1 and 2 similar to those of male. PEREON. Gnathopod 1 (Fig. 3C) equal in size to gnathopod 2 (Fig. 3D), subchelate; coxa triangular, slightly longer than wide, posterior margin excavated; basis not expanded; merus trapezoid; carpus slender, well developed, longer than merus and propodus; propodus slender, palm with long setae along posterior margin and a line of three setae on outer face; dactylus long and curved, overreaching the palmar angle. Gnathopod 2 (Fig. 3D) weakly chelate; coxa subrectangular, slightly longer than wide with a rounded ventral margin; basis expanded posteriorly with 4 small setae on posterior margin; pellucid lobes on merus, carpus and propodus; merus trapezoid with 2 setae near the pellucid lobe, carpus triangular, enlarged at it distal end and armed with setae of various length; propodus triangular, 2 × as long as wide, inner face with many setae of various length, pellucid lobe well developed, extending beyond palm, palm transverse fringed with many apical setae of various length; dactylus short, reaching to half of palm. Pereopod 3–4 (Fig. 4 C–D) not modified, sexually dimorphic. Pereopod 3 ischium modified; carpus short, shorter than merus and propodus, merus, carpus and propodus longer on pereopod 3 than on pereopod 4; pereopod 4 merus as wide as carpus and propodus. Pereopod 5 basis subrectangular without posterodistal lobe. PLEON. Uropod 3 (Fig. 5D) peduncle without facial setae; ramus without marginal setae. Telson (Fig. 5F) weakly cleft with one group of 3 marginal setae on each lobe and 2–3 apical setae. Differential diagnosis The genus Cerrorchestia currently contains only one species: C. hyloraina Lindeman, 1990. Cerrorchestia taboukeli sp. nov. differs from C. hyloraina in several characteristics: maxilliped inner plate bordered by 4 robust pappose setae; number of setae on posterior margin of basis of gnathopod 1; gnathopod 2 carpus triangular, very small, palm longer than wide; pereopods 3–4 sexually dimorphic; pereopod 4 with a denticulate patch; pereopod 5 base ovate with deep posterodistal lobe reaching distal end of ischium; pereopod 6 coxa bilobed without carina; pleopod 3 peduncle with 8 articles; uropod 1 peduncle with 1 row of 5 setae; uropod 3 ramus with 1 dorsal marginal seta; telson sexually dimorphic, telson of males wider than long, cleft until half of length, each lobe with 2 or 3 marginal and 2 apical setae, telson of female weakly cleft with one group of 3 marginal setae on each lobe and 2–3 apical setae. Identification key to known species of terrestrial amphipods from Central America and Caribbean Islands (updated from Lindeman 1990) 1. Gnathopod 2 sexually dimorphic, gnathopod 2 longer than gnathopod 1........................................ 2 – Gnathopod 2 not sexually dimorphic, gnathopods 1 and 2 similar in size....................................... 4 2. Pleopods 1–3 vestigial; uropod 1 without an interramal seta.... Cariborchestia xerophila Smith, 1998 – Pleopods 1–3 multi-articulated, normally developed; uropod 1 with an interramal seta................. 3 3. Gnathopod 2 carpus longer than wide, palm almost round, pereopod 3 dactylus without denticulate patch, pereopod 5 basis ovate without posterodistal lobe, pleopod 3 with up to 6 articles............................................................................... Cerrorchestia hyloraina Lindeman, 1990 – Gnathopod 2 carpus short, palm longer than wide, pereopod 4 dactylus with a denticulate patch, pereopod 5 basis ovate with a deep posterodistal lobe reaching the distal end of the ischium, pleopod 3 ramus with more than 6 articles...................................... Cerrorchestia taboukeli sp. nov. 4. Pleopod 3 ramus vestigial; uropod 1 interramal seta with hooked spade-like tip, uropod 2 outer ramus lacking dorsal setae................................................................................................................ 5 – Pleopod 3 ramus multi-articulated; uropod 1 interramal seta simple, uropod 2 outer ramus with dorsal setae........................................................................................................................................ 6 5. Uropod 1 peduncle with simple setae, pleopod 3 peduncle 0.4 × as long as uropod 2 peduncle, antenna 2 flagellum as long as or smaller than the peduncle, maximum size of adults 7 mm...................................................................................... Talitroides alluaudi (Chevreux, 1896) – Uropod 1 peduncle with bifid setae, pleopod 3 peduncle>0.6 × as long as uropod 2 peduncle, antenna 2 flagellum as long as or smaller than the peduncle, maximum size of adults 13 mm.......................................................................................... Talitroides topitotum (Burt, 1934) 6. Uropod 1 outer ramus without setae; pleopod rami equal in length or shorter than the peduncle... 7 – Uropod 1 outer ramus with setae; pleopod rami longer than the peduncle..................................... 10 7. Pleopod rami ⅓ of peduncle, telson quadrangular without dorsal setae uropod 3 base of peduncle narrow........................................................................... Caribitroides genaroi Ortiz & Lalana, 2009 – Pleopod rami equal in length to peduncle, telson triangular with dorsal setae, uropod 3 base of peduncle wide................................................................................................................................... 8 8. Pleopod 3 comparable in length to pleopod 2, rami of each pleopod approximately equal in length; maxilliped inner plate sparsely setose, with apical spine teeth distinct................................................................................... Caribitroides newtoni Lindeman, 1990 – Pleopod 3 comparable in length to pleopod 2, rami of each pleopod unequal in length; maxilliped inner plate setose, with apical spine teeth distinct............................................................................ 9 9. Pleopod rami distinctly unequal, outer shorter; telson lobes with 1 apical seta..................................................................................... Caribitroides tuxtlensis Lindeman, 1990 – Pleopod 1–2 rami distinctly unequal, inner rami shorter, pleopod 3 rami subequal; telson lobes with 2–3 apical setae............................................................... Caribitroides jamaicensis Bousfield, 1984 10. Epimeron 3 quadrate; coxal plate 6 without tiny spines anterior to carina; maxilliped palp article 2 wide (medially much wider than article 3)...................... Mexitroides chiapensis (Lindeman, 1990) – Epimeron 3 with distinctive curved ventral margin; coxal plate 6 with tiny spines anterior and posterior to carina; maxilliped palp article 2 narrow (medially little wider than article 3)................................................................................... Mexitroides pecki (Lindeman, 1990) Ecology and distribution Cerrorchestia taboukeli sp. nov. was found in very wet conditions of the Pitons du Carbet Mountain Range (annual precipitation higher than 6000 mm per year) always at an altitude higher than 1000 m. At this altitude, the cloud forest is sparse, alternating with mountain grassland (Fig. 6A). It is worth noting that C. taboukeli sp. nov. was found only under tree patches in a shaded environment where leaves of Clusia mangle and Schefflera attenuate create a thick litter layer on the soil. During daylight, the animals rest almost motionless under the leaf litter unless disturbed, in which cases they actively jump in search for shelter. Live C. taboukeli sp. nov. are very dark brownish red (Fig. 6A). Using a quadrat of 25 × 25 cm, the population density was estimated to be, on average, 196 ± 112 ind/m 2 (n = 9). The sex ratio of adults was biased toward females, and juveniles represented more than 75% of the population during the sampling period. The other species of the genus, C. hyloraina, is known from Panama to Costa Rica in similar environmental conditions (Lindeman 1990). The species live in leaf litter of cloud forest with an andosol developed on volcanic rocks (andesite). The main soil characteristics are given in Table 1. To date, the distribution of C. taboukeli sp. nov. is restricted to only two localities in the Pitons du Carbet Mountain Range (Martinique Island). Prospecting the three other islands of Lesser Antilles having large mountain ranges covered by tropical rainforest (i.e., Guadeloupe, Dominica and St Lucia) could elucidate whether other species of forest-hopper talitrids inhabit the Lesser Antilles and also whether C. taboukeli sp. nov. is strictly endemic to Martinique.Published as part of Piscart, Christophe, Ayati, Khaoula & Coulis, Mathieu, 2019, Cerrorchestia taboukeli sp. nov., a new terrestrial amphipod (Amphipoda, Talitridae) from Martinique Island, pp. 1-14 in European Journal of Taxonomy 588 on pages 3-11, DOI: 10.5852/ejt.2019.588, http://zenodo.org/record/365995

Diversity and distribution of freshwater amphipods from Tunisia

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TWO NEW SPECIES OF GAMMARID AMPHIPODS FROM TUNISIAN FRESH WATERS (AMPHIPODA, GAMMARIDAE)

International audienceThis study describes two new species of the genus Echinogammarus from springs and rivers located in northern Tunisia. These two species are related to the Echinogammarus sitnoni-group, but differ from those species in terms of several characteristics, such as a 3-articulated accessory flagellum of the first antennae, the lack of a dense setation on the second antennae, the presence of lateral setae on the telson and the lack of plumose setae on uropod 3. The first species, Echinogammarus carthaginiensis n. sp., is easily distinguishable from the second, Echinogammarus tunetanus n. sp., by the setation on the mandibular palp and gnathopods and the relative length of uropods 1 and 3. A full description of the two new species and information about their distribution is given in this paper

Diversity and distribution of freshwater amphipods from Tunisia

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Origin, diversity and distribution of freshwater epigean amphipods in Maghreb

Northern Africa, although one of the world hotpots of biodiversity, is poorly studied and the freshwater fauna living in this part of the world remains partly unknown. This study focused on the diversity and distribution of the poorly known epigean freshwater amphipods. We performed an exhaustive analysis of the literature on this group of crustaceans and sampled 106 additional localities from the eastern part of Algeria and in Tunisia. Our results showed an important diversity with 25 species (including the presence of at least three new undescribed species) and a very high rate of endemism with 52% of species occurring at on only 1 or 2 sites. We also highlighted a very low diversity on each site with only 4.4% of sites harboring more than 1 species. The comparative distribution of certain species between Europe and Maghreb and also between the western and eastern part of Northern Africa allow us to discuss some hypotheses about the factors underlying this endemism and the biogeographical origin of species. However, our study revealed a general lack of knowledge in the region, especially in the South of Morocco and Algeria. Hence, more information would be needed to propose adapted conservation strategies of freshwater fauna in Maghreb.Our results showed theimportant diversity of Maghreb despite the scarcity of fresh waters and the weak knowledge on this area. We highlighted a very high rate of endemism with 52% of species occurring at on only 1 or 2 sites. We found enough data to discuss some hypotheses about the factors underlying this endemism and the biogeographical origin of species

Origin, diversity and distribution of freshwater epigean amphipods in Maghreb

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Conservation of freshwater biodiversity in Tunisia in a climate change context: combining amphipod distribution data and molecular analyses to improve priorities

International audienceThe exceptional diversity of freshwater fauna of the Mediterranean Basin currently faces a crisis in which climate change combined with overexploitation of freshwaters heavily threatens the local fauna. In this context, it is urgent to define conservation priorities on how to best protect freshwater biodiversity. One of the main limits to define such actions remains the lack of knowledge in many countries. In this study, we test the usefulness of molecular data (COI gene) combined with morphological identification to better predict the pattern of biological diversity and threats of climate change on freshwater biodiversity. We focused our study on the freshwater amphipods as model organisms in order to define conservation strategies in Tunisia, one of the most threatened countries. Our results confirmed that amphipods diversity is largely underestimated with nine species identified by their morphology and 33-39 species assigned depending on delimited with the most parsimonious molecular delimitation method. The distribution of amphipods is mainly restricted to the northern part of Tunisia and seems to be positively correlated with precipitation and negatively correlated with thermal amplitudes and precipitation fluctuations. These environmental factors are sensitive to climate change and confirm that conservation strategies need to be redefined and adjusted in the face of future climate predictions. Moreover, the total diversity and spatial distribution patterns provided by molecular methods seem to be more detailed and accurate than results based on morphology alone and nicely complement traditional species assignment