Would you like to propose yourself a quiz for fun ? Then, please simply drop us a mail (mailbox of editor at the end of this page).

Here are the answers to the various quiz scattered throughout this website (including the old quizzes that have been removed by new ones, for your information and pleasure).

Quizzes are separated by a large blank space: you can then look at them individually… or if you are curious and not patient, in a row!

If you succeed to all, you are a most knowledgeable expert!

Quiz33 :

Can you name major differences in terms of morphology, behavior, biology that separate all oviparous and all viviparous groups ?

The most obvious difference are of course the breeding strategy, egg-laying vs. livebearing and the presence of a gonopodium in male in place of standard Anal fin, but that is not so simple, because some sp. are oviparous and show a pseudo-gonopodium (Tomeurus gracilis, all Campellolebias, Cynopoecilus sp.) in South America, and reversally there is the mythic, never confirmed by modern methods, case of normally oviparous Epiplatys sp. that is viviparous in Sudan, temporarily assigned to bifasciatus and-or to spilargyreius-marnoi ; other major differences are the capacity of some (not all) oviparous groups to have their embryonic development time extended in some peculiar conditions, up to diapauses states and annualism (some diving deeply into substratum) ; other major differences are the capacity of some (not all) viviparous groups to readily hybridize in nature (for oviparous groups it is not evidenced, yet). Back

Quiz32 :

Several oviparous and viviparous species show very large or huge distributions over coastal fringes, with or without molecular speciation, with or without ubiquity in hypersaline-marine-brackish-fresh waters… can you name at least three ?

Over 15 species fits the definition : Aplocheilichthys spilauchen in western Africa, Kryptolebias marmoratus-ocellatus {or hermaphroditus}, in eastern northern and southern eastern America, through Caribbean arch, Poecilia vivipara, similarly but only from Trinidad southerly, Aphanius fasciatus and dispar all along Mediterranean sea and nearby Red Sea and northern Indian Ocean, Pandanodon stuhlmanni, in Eastern Africa, Fundulus heteroclitus-macrolepidotus, Fundulus grandis-grandissimus, Fundulus majalis-similis-persimilis, Cyprinodon variegatus and its clinal (sub)species in eastern North America and nearby Caribbean Arch, Poeciliopsis elongata-paucimaculata-retropinna, in western Pacific central America. Back

Quiz31 :

A species of viviparous Cyprinodontiformes is historically named as a killifish and it has a very small size in male… can you name it ?

Heterandria formosa, commonly named 'Least Killifish' with a huge range, in Atlantic and Gulf Coast drainages, southeastern and southern USA, in freshwater, brackish water, from Berkeley county, South Carolina state, south through eastern and southern Georgia state and peninsular Florida state, westerly near Gulf coast to New Orleans, Louisiana state, and even eastern Texas state, as a recent invader after floods. Back

Quiz30 :

There are some cases of perpetual cases of all-female hybrid species in viviparous Cyprinodontiformes producing clones from sperm of distinct species… could you name at least one case ?

In genus Poecilia, there is one case, Poecilia formosa : among 3 stable species considered to have originated (independently) through natural hybridization and have ranges that coincide the ranges of their assumed parent species, (1) formosa (mexicana limantouri x latipinna), a gynogenetic species, producing clones, (2) kykesis (mexicana? x petenensis), a standard bisexual species, and (3) latipunctata (mexicana x latipinna), a standard bisexual species ; in genus Poeciliopsis, several cases of hybridization produce unisexual clones, but they do not become isolated with speciation and they rather form complexes, such as lucida-monacha or monacha-occidentalis or monacha-viriosa or even triploid unisexuals. Back

Quiz29 :

The so-called sword is well known in male of some (not all) species of genus Xiphophorus, what large species is having the longest sword in percentage of S.L. ?

Xiphophorus hellerii, reaching 22 cm in male, with sword up to 2 thirds of body size. Back

Quiz28 :

Surprisingly, the most frequently used root (with more than 3 letters) for Killifish names is "mann" which means Man in German. Is it for 9, 11, 15, or 19 taxa ?

19 taxa (including synonyms) : Aphyolebias wischmanni, Aphyosemion fellmanni, Aphyosemion heinemanni, Aphyosemion hofmanni, Aphyosemion tessmanni, Epiplatys neumanni, Epiplatys chaperi spillmanni, Gambusia manni, Jenynsia eigenmanni, Leptolucania mannii, Nothobranchius neumanni, Pantanodon stuhlmanni, Phalloptychus eigenmanni, Poropanchax manni, Pterolebias bokermanni, Rivulus kuelpmanni, Rivulus wassmanni, Simpsonichthys bokermanni, Xiphophorus birchmanni. Back

Quiz27 :

Which city of the world holds the largest number of species with their type locality there ?

New York ! Surprising, but not too much. Many of them are synonyms because US immigrants did collect there without knowing previous collections. The list is long with 11 names : Fundulus heteroclitus macrolepidotus, fasciatus Bloch & Schneider, flavidus, pisciculus, viridescens, zebra DeKay, pisculentus, fasciatus DeKay, flavulus, zonatus Mitchill, and Cyprinodon ovinus, plus, a bit away from the Big Apple, Fundulus diaphanus diaphanus and Fundulus majalis described from Long island. Back

Quiz26 :

Only 1 species name of Cyprinodontiformes native of Amazon basin starts with the letter "q". What is it?

The species name, quiii (for Moema quiii), is a noun in apposition and is proposed by the discoverer Lance R. Peck, a biologist, animal photographer and exporter, based in Puerto Maldonado, as a dedication to his wife Belinda who was given the name "Qui i i" by an Ese eja shaman friend years ago. According to him, «the name is derived from the Ese eja word "Qua' i i" which means hummingbird (picaflor). However, "Qui i i" (with a twist of sound) is the name for the "hummingbird of the water"». Back

Quiz25 :

A unique case in Cyprinodontiformes : for the same fish, two monotypic genera, one being a synonym, and two species names, one being also a synonym obviously. What is it?

Lamprichthys tanganicanus. Also assigned to another new genus Mohanga, a few months later. The female, dimorphic, has been described as Lamprichthys curtianalis (curtianalis means short Anal fin !) and obviously it is a synonym. Back

Quiz24 :

Scale reduction on Aphanius or Orestias species are common. But, could you name at least one species of each genus completely naked (there are 4 in total)?

Aphanius asquamatus, Aphanius furcatus, Orestias minutus, Orestias minimus. Back

Quiz23 :

Branchiostegal appendages are occasionally seen in dominant males of 3 African lampeyes genera. Which ones?

Procatopus, Plataplochilus, Hylopanchax. Back

Quiz22 :

Sexual differences in the number of Anal fin rays are well known for oviparous species of Cynolebias and allied genera and for all ovoviviparous species (because male gonopodium, with much reduced ray counts, is replacing Anal fin). But, is a similar dimorphism reported among African killifishes ?

Yes, for Lamprichthys tanganicanus (and for that reason, 2 taxa were described, the other for the female, curtianalis, a junior synonym). Back

Quiz21 :

What are the most northern and the most southern two species of Epiplatys?

Epiplatys spilargyreius in the North (in an oasis of the Sahara desert) and Epiplatys atratus in the South (in Kasaï province of Zaïre or Democratic Republic of Congo, at about 6° South latitude). Back

Quiz20 :

Is there a deep-bodied Killifish in Borneo (Kalimantan, Indonesia)? What is the native killifish of that Asian island?

It is Jordanella floridae artificially planted after having escaped from fish farms. The native killifish species, Aplocheilus panchax s.l., is very slender. Back

Quiz19 :

Could you name at least 3 Cyprinodontiformes species that hold no Ventral fins?

There are many, many, all oviparous, such as Cyprinodon diabolis, Megupsilon aporus, Aphanius apodus, Simpsonichthys boitonei, Simpsonichthys chlolopteryx, Simpsonichthys parallelus, Simpsonichthys nigromaculatus, Rivulus nudiventris, Rivulus nelsoni, Tomeurus gracilis, Empetrichthys latos and Empetrichthys merriami, all known Orestias and Crenichthys species (and some others only vestigial Ventral fins, e.g. Rivulus planaltinus. Back

Quiz18 :

Xanthic variants have been reported among oviparous and viviârous Cyprinodontiformes from aquarium breeding and have even been erroneously described, such as Aphyosemion australe hjerressensii or Rivulus urophthalmus auratus. But, have xanthic killifishes been reported from nature ? And, if yes, which species ?

Yes, Cyprinodon salinus salinus occurs at type locality in both forms, normal and xanthic, with a proportion of 4 per thousand for the latter. Back

Quiz17 :

What is the smallest Cyprinodontiformes and could you name at least five species, both in oviparous and viviparous groups, not more than 25 mm (one inch) in male or in female, in total length ?

The smallest currently known sp., max. 2 cm, is Fluviphylax palikur from northeastern Brasil and Guyane (its congeners gouldingi, obscurus, pygmaeus, simplex, wallacei, zonatus are about the same size). Dwarf species, slightly larger (2.5 cm), are Cnesterodon raddai, Congopanchax brichardi and myersi, Gambusia amistadensis, aurata, dominicensis and hurtadoi, Heterandria formosa, Lacustricola jeanneli and usanguensis, Neoheterandria cana, elegans and tridentiger, Plesiolebias glaucopterus and lacerdai, Stenolebias damascenoi and bellus, Poecilia araguaiensis, bifurca, branneri, hasemani, minima, obscura, sarrafae and wingei, Poeciliopsis prolifica, Simpsonichthys semiocellatus and costai, Priapichthys caliensis and nigroventralis, Quintana atrizona. Back

Quiz16 :

At least 10 Cyprinodontiformes species have their type locality in the region of the Niger delta, Nigeria. Only one is unknown live. What is its name?

Fundulopanchax powelli, only known by preserved juveniles, from the eastern part, close to Cameroun border (and unfortunately the situation has not changed since 1994). Back

Quiz15 :

Is there a Cyprinodontiformes that produces offspring of clones from a single individual without any need of a male and without ethical problems, nor lobbying by activists?

Yes the self hermaphrodite Kryptolebias marmoratus and ocellatus (also named hermaphroditus). Back

Quiz14 :

Which marine island of the world has the highest density of Cyprinodontiformes species per square kilometer?

Bermuda, with two Fundulus species in a tiny island, bermudae and relictus. Back

Quiz13 :

One Cyprinodontiformes species has been sent to space, within an Apollo mission, for laboratory experiments. Do you recall its name?

Fundulus heteroclitus. Back

Quiz12 :

The largest and one of the smallest Aphanius species have both a unique vertically angled lower jaw. Can you name them?

Aphanius splendens (5 cm) and Aphanius stiassnyae (10 cm). Back

Quiz11 :

Only one Rivulus-like non-annual species is reported as far South as Argentina. Is it aplocheiloides, luelingi or punctatus?

Rivulus (Melanorivulus) punctatus (water can cool down to 6°C!). Rivulus (Atlantirivulus) luelingi is only reported from Brasil and aplocheiloides, also from Argentina, is Rivulus-like, but it is annual and a Trigonectes species. Back

Quiz10 :

If several annual Cyprinodontiformes are living in the same temporary pool, this means that their eggs must have the same standard incubation period. True or false?

No, it has been demonstrated that fry of small species belonging to the genera Simpsonichthys et al. appears first, followed much later by larger Cynolebias species that grows much faster. Depending on the date of collection, the killifish fauna of a temporary pool may then vary. Back

Quiz9 :

What is the African country, South of the Sahara desert, where no annual Cyprinodontiformes has yet been reported?

Angola (but this is not the last word on the matter : too few collections). Back

Quiz8 :

Could you name at least 2 Cyprinodontiformes species with a long extension in the middle of male Caudal fin (not upper and-or lower streamers)?

Maratecoara lacortei, formosa, splendida, gesmonei, Pseudepiplatys annulatus. Back

Quiz7 :

Water chemistry, and notably pH, has been suggested to influence significantly the sex-ratio in killifish offspring. Is this true and why?

Yes, it is definitely true. The reasons, though, are unknown yet, unlike for human beings. Back

Quiz6 :

Much is known on the famous aquarium species Aphyosemion australe. Would you agree on these 2 provocative assertions : it has been collected in brackish waters; it has been proved to be a semi-annual species with incubation times of up to 8 weeks?

Absolutely true. Aphyosemion australe has been collected with the brackish Poropanchax stigmatopygus and incubation on wet peat is easily achieved for at least 6 weeks. Back

Quiz5 :

Are there any Aphyosemion species with a reversed color pattern, exemplified by blue (not red) spots on a red-brown (not blue) background on male sides?

Yes, all species in Diapteron, such as cyanostictum, georgiae, fulgens, abacinum, seegersi. Back

Quiz4 :

Is there a Cyprinodontiformes species that is known only by a single stable population of less than 500 specimens in total? If yes, then name this Pupfish.

Yes, Cyprinodon diabolis from Devil's Hole, USA, a unique case among fishes in general (but highly threatened of extinction). Back

Quiz3 :

Are you aware of any Cyprinodontiformes species female in Africa with black peppered dots on entire body? If yes, name it.

Adamans or Fenerbahce formosus, but not all in a population (a presumably primitive character)… and if not only Africa is considered, black peppered female are well known in viviparous Cyprinodontiformes… and not only in female, e.g., in male Gambusia holbrooki (also as a proportion of a population). Back

Quiz2 :

Predatory behavior on smaller Cyprinodontiformes species is part of life for components of Cynolebias and Megalebias of South America. Is there a species with the same predatory behavior in Africa or in North-Central America, and if yes, which one(s) ?

Nothobranchius (Paranothobranchius) ocellatus in Africa and Belonesox belizanus in North-Central America (probably also Orestias cuvieri in Andean plateaux, but it is not fully demonstrated). Back

Quiz1 :

Do you think possible to bring back mud from biotope containing annual killifish eggs? If yes, who did perform this for the first time and with which species?

Yes, it was achieved by the Belgian biologist Marc Bellemans in Sudan with Nothobranchius aff. rubroreticulatus and virgatus. The clay mud produced hundreds of fry of the two sympatric species. Back