<![CDATA[WCS - Blog]]>

<![CDATA[WCS - Blog]]>Fri, 07 Feb 2025 22:07:32 -0800Weebly<![CDATA[Planktic Foraminifer Genera, Ranked]]>Fri, 13 Sep 2019 04:02:56 GMThttps://www.utmicropaleo.com/blog/planktic-foraminifer-genera-rankedForaminifera are great, but they are not equally great. While some are miraculous examples of the myriad diversity of life, others are, I’m sorry to say, ugly. It is therefore important to rank them correctly. The Best Foram Tournament is a low-brow, gauche popularity contest where anyone (even geochemists) can vote, but this ranking is based purely on the intrinsic value of each genus of planktic foraminifera. It is objectively correct and – this cannot be stressed enough – inarguable. Genera are ranked primarily on aesthetics (of both morphology and name), biostratigraphic and paleoecological usefulness, and overall ~ vibe ~. Click on the genus name to see its Mikrotax page.

Helvetoglobotruncana – Absolutely perfect. Biostratigraphically important but more importantly, beautiful. Planoconvex with those excellent single keels in the advanced form, H. helvetica, paired with the large, inflated chambers on the top. The little flexure that gives each of the chambers on the final whorl a fun angle is a nice addition, too. *chef’s kiss*
Globotruncanita – If I’m being honest, I’m not the biggest fan of double keels. Yeah, it’s the classic Cretaceous look but they make taxa look chunky. Single keels are more sleek, more elegant. That’s why Globotruncanita is better than Globotruncana. Gt. stuarti, in particular, is one of the prettiest forams of the Cretaceous.
Hantkenina – The quintessential tubulospined planktic foram, and a classic of the Eocene. Its extinction coincides with the E-O boundary, the onset of permanent southern hemisphere ice sheets, and the oceanographic reorganization that accompanied it. RIP.
Acarinina – Acarinina always looks so sharp. (“Spiky” sharp not “well-dressed” sharp.) The muricae contribute to that, and the best ones (topilensis, quetra, wilcoxensis) have that great angular periphery when viewed from above.
Orbulina – Kind of amazing that there’s only one perfectly round species of foram, right*? You’d think this would have come around once or twice before the mid Miocene, especially considering all the iterative evolution in planktic foraminifera (Ok, sort of Orbulinoides, but that’s a skewed version of the idea, like that repainted Christ fresco in Spain). While it’s obviously an easy species to identify it’s often a hard one to pick when you’re at sea and there’s a decent pitch/roll, and they all go rolling off to one side of the tray and then the other. Come back! you say to your microscope, as the other people in the lab pretend not to look at you. Also it’s pretty cool that they have some morphologically distinct genotypes with clear environmental preferences and calcification depths. There’s something for everyone: biostratigraphers AND geochemists can come together to appreciate Orbulina.
*Don’t say there are multiple genotypes; I know
Praeorbulina – Speaking of evolution, the Praeorbulina-Orbulina series is a really nice example of it. Get rid of horse hooves or whatever and put this genus in the text books, in my opinion. They’re great for biostratigraphy, too; you always know right where you are in the mid Miocene with Praeorbulina.
Globorotalia – Good ol’ Globorotalia. There are some real classics in here. menardii, tumida, truncatulinoides. What’s the most under-rated Globorotalia, do you think? For me it’s G. scitula. Just a nice compact little sub-thermocline dweller.
Globotruncana – The platonic ideal of Late Cretaceous foraminifera. Big, double keeled, ornamented, and diverse.
Leupoldina – 5 species of bonkers excursion taxa during OAE1a. A+
Plummerita – A trochospiral genus with tubulospines AND rugosities. A fitting marker (in the form of P. hantkeninoides) for the very last zone of the Cretaceous, by which time things had gotten weird.
Morozovella – The most Extra Paleocene species, with often thick keels and muricae. M. velascoensis is the best one, obviously, but that whole angulata-velascoensis lineage is full of bangers. The muricae around the keels, sutures, and ad-umbilical ridges of many Morozovella looks like hoar-frost, which is maybe a strange comparison when considering these things lived in some of the warmest surface waters of the part 100 million years, but it’s pretty unique among the planktic foraminifera and I love it.
Globigerinatella – Get a load of this weird alien.
Hastigerinella – What’s going on with this thing? One(?) of the only species to live in modern oxygen minimum zones, which, uh, will probably be an evolutionary advantage in the near future.
Guembelitria - OK, it’s boring to look at, but it survived the K-Pg boundary and was a dominant member of open ocean populations well after its fellow survivors given way to their descendants.
Radotruncana – Tubulospines but no rugosities. Still pretty out there, even for the Late Cretaceous.
Astrorotalia – a rehash of Radotruncana in the Eocene.
Racemiguembelina – Unique among the Cretaceous multiserial taxa in that it went nuts in three dimensions.
Planoglobulina – My brother says these look like grape fruit snacks and he’s not wrong.
Gublerina – A weird multiserial taxon AND it’s fun to say.
Eohastigerinella – It only contains E. watersi but E. watersi rules. It’s VERY digitate, plus it’s got a cool name. I know Cushman named it after someone named Waters but it’s fun to imagine that it’s named after the liquid that covers 2/3 of the Earth.
Conoglobigerina – small and boring looking but it was the first species of planktic foraminifera so we’ll let that slide. Thanks for escaping the benthos and inventing planktic forams, little friend.
Parvularugoglobigerina – What’s not to love here? It’s one of the first new genera to evolve in the Paleocene, it’s got a weird-ass name that’s fun to say, it looks distinctive, and it’s biostratigraphically useful.
Eoglobigerina – Notable for being the first genus to evolve spines in the earliest Paleocene. Spines are cool because they let forams eat larger, swimming zooplankton. It’s always been amazing to me that foraminifera, single-celled protists, can capture and eat swimming animals that have limbs and organs and eyes and whatnot.
Lunatriella – This is one of those ones that’s so weird they stuck it in its own genus. Even though it’s from the Cenomanian of the US Western Interior I’ve never seen one, and honestly I’m pretty mad about that.
Asterohedbergella – Look I'm a lumper and even I think they were right to erect a whole new genus just for this. Supposedly they live in the Cenomanian but I have yet to see one.
Rugoglobigerina – I’m a big fan of Rugoglobigerina. Just big chambers and rugosities.
Thalmanninella – Hell yeah, keeping things interesting in the Cenomanian. Always happy to see a greenhornensis.
Abathomphalus – a tongue-twister genus from the Maastrichtian. I like them because they’re all boxy looking.
Rotalipora – Good ol’ Rotalipora. Single keeled, lots of apertures, biostratigraphically significant. You could do a lot worse than Rotalipora.
Fohsella – Globorotalids with mohawks. My PhD advisor has a poster in his office of F. fohsi that says “WANTED, DEAD AND WELL PRESERVED: MOHAWK GUY” and I always think off that with this genus. More importantly though the evolution of this lineage provides some very nice biostratigraphic markers for the cooling of the mid Miocene.
Sphaeroidinella – Looks like it dressed up as a ghost for Halloween.
Planorotalites – Neogene foreshadowing in the middle Paleogene. There’s even one called pseudoscitula (guess what it looks like).
Planomalina – I think this is the only planispiral bug with a keel? Anyway, not bad for the Early Cretaceous.
Planoglobanomalina – Planomalina put a few of their best and brightest into a tiny time machine right as OAE1d was beginning and sent them ahead 50 myr to the early Eocene, where they lived happily for a few million years before going extinct with no descendants.
Pseudoplanomalina – At first I was mad because it’s a single-species genus with “pseudo-“ in front of the genus it should actually be in but then I remembered that P. cheniourensis looks cool as hell; it’s like a tiny ammonite.
Paraticinella – “rohri” sounds like if Scooby Doo tried to say my last name.
Pseudothalmanninella – Finally some keels! That statement doesn’t make any sense if you’re reading this list in order but if you were working your way up through time you’d be very happy to see Pseudothalmanninella after those boring bugs from the Jurassic until this little guy. Things were just starting to get interesting in the Albian.
Dicarinella – A diverse and abundant middle Cretaceous genus with those classic double keels. The best species here are D. concavata and D. asymetrica, with that absolutely flat spiral side and vaulted chambers on the umbilical side.
Parasubbotina – This set the mold for so much of what came after in the Cenozoic. The Dinosaur Jr. of planktic foram genera.
Globoturborotalita – My PhD advisor doodled a cigarette drooping out of the aperture of G. nepenthes in his copy of Kennett and Srinivasan, and that’s the only thing I think of when I picture this genus.
Globoconella – Some good ones in here. I like G. conomiozea.
Igorina/Pearsonites – Part of that middle Paleocene wave of bigger, more interesting taxa with photosymbionts. I like how these are so extra, too. They have lots of chambers, sometimes a keel, can be inflated, and are very biconvex. The important post-K-Pg recovery was the return to cool-looking normal forams, and Igorina, Acarinina, and Morozovella were the ones who did it. I disagree with Soldan, who split out Pearsonites (sorry Paul! nothing personal) from Igorina, taking some of the best ones (broedermanni and anapentes) away from that genus.
Praemurica – the first group to re-evolve photosymbionts in the Cenozoic! Cool.
Globigerinelloides – A solid genus. Easy to find (all the non-weird planispiral things in the Cretaceous) but with a decent amount of morphological variability, within its fairly boring constraints. Pretty lame compared to the other members of GLOBIGERINELLOIDIDAE, though.
Pseudohastigerina – OK this is just more Globigerinelloides but in the Paleogene.
Alicantina – I used to go to a bar in Taos, NM called the Alley Cantina. It was, appropriately, in an alley off the main plaza, and was a required stop, after Walmart, the local outfitter, and the book store (called Moby Dickens) when we used to come into town on days off when I was working in the mountains there. They had a great happy hour and a shuffleboard table in the back and I have fond memories of drinking a margarita with friends while afternoon thunderstorms raged outside. Anyway, maybe this genus is named after that bar. I’m not gonna look it up to check.
Trilobatus – This one’s got sacculifer, which is great, but what I really like about it is the big radiation within this genus at the very start of the Miocene. The Oligocene ended and they were like, ahhhhhhhhh, that sucked, thank god that’s over.
Archaeoglobigerina – Why is it archaeo-Globigerina? It looks nothing like Globigerina. It’s a good genus, though, mostly because I like to say “imperforate peripheral band.”
Whiteinella – Like Hedbergella, but bigger and more stratigraphically limited, and therefore more interesting.
Clavigerinella – A middle tier clavate/digitate genus. We all love a good elongated chamber but there are better examples than this. Still, a pretty middle Eocene species. It’s main contribution is giving rise to Hantkenina.
Morozovelloides – This would be ranked a lot higher if Morozovella didn’t exist.
Hedbergella – Ubiquitous in the Cretaceous. The archetypal Mesozoic trochospiral form. Trochospiral is cooler than biserial, so it ranks just above Heterohelix, but please understand that they have identical vibes.
Heterohelix – Ubiquitous in the Cretaceous. Heterohelix is the archetypal biserial foram, which is both boring but impressive. A solid C.
Muricohedbergella – I understand why they had to split a bunch of genera off of the classic Hedbergella but I do wish they’d gone a bit more creative with the names. Members of thus genus survived the K-Pg and are the ancestors of a ton of interesting Cenozoic taxa. Too bad they weren’t more interesting themselves.
Hastigerina – Just one species here but it’s a good one: pelagicus. Tri-radiate spines! Finally some spine innovation after 58 million years. I wonder what kind of weird spines there will be 50 million years from now?
Globigerinoidesella – G. fistulosa was one of the first forams I thought was really cool when I started learning about forams. The Dave Matthews Band of planktic taxa. I’ve since moved on.
Dipsidripella – Look these are morphologically completely uninteresting but I love the name. It’s named after the Deep Sea Drilling Project (DSDP) if you didn’t know. That’s great! This should’ve set a precedent, but it’s not too late. No more tacking on a pseudo- para- -oides –ella to an old genus name. Have fun with it! And more things should honor scientific ocean drilling! It’s at least as fundamental to our science as the contributions of any one micropaleontologist. Let’s name the next new genus Iodpoides. Ayeohdeepoides?
Praeglobotruncana – A solid middle Cretaceous keeled taxon that’s fun to see in your mid Cenomanian samples. A nice preview of what was to come.
Marginotruncana – Pretty alright. The horseshoe-shaped umbilical sutures are cool, if only that were actually unique to this genus…
Globigerinatheka – You can never have enough apertures, I guess. Fun to say, though.
Clavatorella – A single species genus that probably deserves it. The extreme clavateness of the chambers is pretty cool, but “club shaped chambers” aren’t exactly the picture of elegance.
Catapsydrax – The bulla is cool! It’s cool. It also looks like a diaper on some species. Sorry, I don’t like it any more than you do.
Gubkinella – Boring morphology but fun to say. “Gubkinella.” Nice.
Turborotalia – The late Eocene! Uh, I don’t have any strong feelings about this one.
Laeviheterohelix – Fine. It’s fine
Schackoina – small but distinct.
Hastigerinoides – H. alexanderi is awesome, H. clavatus is pretty cool, but H atlanticus sucks. Garden-gnome-lookin-ass species weighing the rest of the genus down.
Sphaeroidinellopsis – Precursor to Sphaeroidinella, with the same shiny cortex. That’s kind of cool. Could be cooler.
Gansserina – The character generator version of Dicarinella if you moved the “chamber inflation” slider all the way to the right.
Pseudoguembelina – a fun thing about this genus, and Racemiguembelina, and Rectoguembelina, and Chiloguembelina is that we got rid of the actual genus “Guembelina” a while ago.
Beella - [peace sign emoji]
Clavihedbergella – Not the most interesting digitate genus but there are some solid ones in there. C. subcretacea looks like it’s throwing up the peace sign, too, but not as much as Beella.
Candeina – An interesting monospecific genus, with its smooth test, sutural apertures, and maybe a benthic origin.
Favusella – This is the only one with this wall texture, which looks like a waffle, so that’s cool. But it’s a non-phyletic genus because there’s like 5 million years in the middle Aptian where no Favusella exist.
Protentella – The digitate chambers and the apertural lip makes the final chamber look like a hat. P. nicobarensis looks like an opera clown.
Kuglerina – Things were getting weird in the Late Cretaceous and this is a good example, even the inflated globigerine forms were getting a little extra. This one is just BIG.
Biticinella – Pretty cool looking, for an Albian genus.
Contusotruncana – This genus has a high spire, double keels, and lots of ornamentation, but then blows it with the sloppy-looking umbilical chambers of the final whorl in basically every species (shout-out fornicata and morozovae, you guys deserve better than your genus). This is like the Chopped contestant who nails the first two rounds and then makes bread pudding for dessert and somehow completely ruins it.
Globoquadrina – I like how square dehiscens looks, kind of a throwback to the Paleocene/Eocene. Common, biostratigraphically significant, and, importantly, Miocene in age. Cool.
Globigerinella – Some good digitate ones in here, and most of the species in this genus have that nice plump look the best globigerine forms have.
Pulleniatina – Hefty Lads. Chunky Bois. Big tests with a thick cortex.
Quiltyella – Split from Globigerinella for being too digitate. Excommunicated for heretical levels of chamber elongation.
Subbotina – This is basically the same as Globigerinoides and Globigerina but it’s older and therefore cooler. Same basic popcorn-lookin-ass morphology though.
Globoconusa – I like this species for two reasons: 1) it is part of that weird early diversification immediately after the K-Pg, and 2) the most common species is G. daubjergensis and that’s fun to say. Basically, it’s like Parvularugoglobigerina but less so.
Globigerinoides – Imagine if someone asked you your favorite animal, and you looked at the whole grand diversity of the animal world, carefully considered all your options, and then confidently said “squirrels”. That’s what Globigerinoides is. I’m sorry. I don’t make the rules.
Globigerina – The replacement-level foram.
Neogloboquadrina – I’m sorry, this one's ugly. I know it’s geochemically useful, and it’s very cool that coiling direction corresponds to temperature. But they’re just these squat little compact things with no character. Also they look cold, like they’re bundled up. Come on down to the tropics little guy.
Ticinella – honestly the least interesting of the ROTALIPORIDAE.
Globanomalina – Smooth boys of the Paleogene.
Rugotruncana – Too much. If Rugoglobigerina is interesting and understated, Rugotruncana is loud and overdone. A Marvel movie of a genus.
Zeauvigerina – It survived the K-Pg, and that’s pretty cool, but then it didn’t really give rise to anything new, which is kind of disappointing. A missed opportunity. I wonder if it was floating around in the Eocene ocean surrounded by descendants of Muricohedbergella feeling jealous.
Ventilabrella – a solid multiserial group. Not an insane amount of chambers, though.
Sigalia – A multiserial group that also looks like it wants a keel. Just pick one thing guys.
Costellagerina – the poor man’s Rugoglobigerina.
Dentoglobigerina – It’s got a little tooth! Just a lil tooth. This is what passes for interesting in the Oligocene.
Globotruncanella – “Whoa, like Globotruncana??” you might ask, seeing the name and understanding, by this point of the list, how people name genera. NO, it looks NOTHING like Globotruncana, you rube. It’s just kinda flat and petal-shaped. Whatever.
Orbulinoides – Dollar Store Praeorbulina.
Microhedbergella – Like Hedbergella, but smaller. Look: “Microhedbergella differs from Hedbergella primarily by its generally smaller size, particularly in the early species”
Anaticinella – Yeah, it’s fine. Nothing wrong with this one. Ok moving on.
Chiloguembelina – The ocean just wasn’t ready to exist without a bunch biserial planktics after the K-Pg. That’s alright, Chiloguembelina was there to fill that Heterohelix-shaped hole until, uh, the late Oligocene.
Rectoguembelina – a benthic that wanted to be a planktic. Good job little buddy.
Gallitellia – Another benthic origins genus, and this time it’s extant. Pretty cool that they keep doing this, I wouldn’t want to live in the benthos either.
Jenkinsina – What would a Guembelitria be without its pore-mounds? This.
Turborotalita – Turbo Time!
Cribrohantkenina – Too many apertures. This takes the classic Hantkenina look and distorts into a nightmarish ghoul with a frozen scream. You could imagine them moaning slightly, in the oceans, as they floated around. No thank you.
Hendersonites – a single species genus that only lives in the Campanian. This is incredibly boring.
Braunella – it’s just a fat Heterohelix. Lame.
Berggrenia – A monospecific genus only known from the Recent! Neat. Somebody should look into this.
Dentigloborotalia – Exactly as morphometrically boring as Berggrenia but with a fossil record, which somehow makes it more lame.
Planoheterohelix – At some point they decided that regular old Heterohelix wasn’t good enough so they made this new genus. I’m not a fan, tbh.
Paracostellagerina – Another single species genus, split from Costellagerina because there’s a gap between the two genera with no morphometrically similar species. As a lumper, I reluctantly approve of this split. Still, if Costellagerina is the poor man’s Rugoglobigerina, what does that make Paracostellagerina?
Woodringina – Biserial with a twist or triserial to biserial, which is hard to see on those tiny little Paleocene forams under a light microscope. Ranked slightly higher than the other lame biserials for being a post-K-Pg radiation genus.
Huberella – look the problem with biserials is the splitters have gone crazy on them several times in the last couple decades and now there’s just too many genera. No offense to Huberella, which at least sounds like a 60s pulp movie franchise.
Ciperoella – From the Oligocene Atlas: “Ciperoella is a common form in the Oligocene that has been regarded by workers as s species of Globigerina. However, it does not have the wall texture of Globigerina. Hence, the naming of a new species.” OK.
Protoheterohelix – Something else that used to just be Heterohelix.
Falsotruncana – What’s going on here? It’s halfway to the cool Late Cretaceous genera, but all the other late Turonian genera (Marginotruncana, Dicarinella, Helvetoglobotruncana) had already lapped it.
Guembelitrioides – Too high a trochospire, and too loosely coiled. It’s sloppy.
Tenuitella – Sometimes it has a bulla.
Globorotaloides – Would it surprise you to learn this genus is a product of the Oligocene?
Paragloborotalia – Look, I love my old labmates and support everything they do, but I swear to god if I have to hear about this stupid genus again…
Orcadia – Oh hey it’s one of the extant monospecific genera I always forget about.
Pseudoglobigerinella – I’m sorry this one’s just boring.
Mutabella - “Like Tenuitella but larger” great thanks.
Bucherina – How sure are we that this isn’t just a Kuglerina that was squished a bit and has some crap stuck to the test?
Praegublerina – there's one species in there, just leave it in Gublerina! We don’t need a whole genus for PRAE-Gublerina.
Globigerinita – Nope.
Pseudotextularia – Other than being biserial, this genus is NOTHING like Textularia.
Trinitella – Morphologically offensive. What’s the deal with the last chamber? It’s just weirdly proportioned. No thank you.
Cassigerinelloita – “A rotating axis of triserial coiling.” Looks like garbage.
Blefuscuiana – If you don’t work on the Early Cretaceous you’re probably wondering if I just made this name up as a joke. Like everything pre-Aptian it looks like trash.
Spiroplecta – I hate these coiled-to-biserial groups, you can NEVER see the coiled part in moderately preserved samples. Hope it’s not important for paleoecology because it’s getting lumped into Heterohelix.
Candeina – It’s described as “coiled biserial” but it looks way messier than that description implies. Just an unorganized blob, which, ironically, makes it pretty easy to identify.
Pseudoguembelitria – gross.
Globuligerina – the second genus of planktic foraminifera. Ugh they still look like that? COME UP WITH SOMETHING MORE INTERESTING.
Gorbachikella – Look I’m trying not to hate on the Early Cretaceous genera too much because I understand they were inventing a whole new morphospace but on the other hand the K-Pg survivors managed to invent a huge new range of interesting morphologies within 10 million years so, you know, maybe they should try a bit harder.
Streptochilus – Neogene biserials, fine, whatever, but the name is gross. 100% sounds like a mutation of the virus that causes strep throat.
Protentelloides – Hey, you’ve got a thing on your final chamber.
Liuenella – I do not like it. A newly erected genus (well, 11 years ago, but new enough) with no representatives for the entire Turonian and Coniacian, and most of the Santonian. New genera should solve the phylogenetic problems of the Cretaceous, not compound them.
Loeblichella – I’m convinced this genus is just different Whiteinella that have just been squished and slightly broken. I have not yet seen a single image of one that didn’t have that squashed looked. Sorry Alfred Loeblich, next time someone feels the urge to add “prae-“ or “pseudo-“ when splitting up an existing genus maybe they’ll name it after you instead.

*Pseudoticinella not included. It’s listed on mikrotax but contains no species.]]>