Morphometric variations of two patellid limpets between artificial breakwaters and natural reefs

Es ua ine, Coas al and Shel Science 297 (2024) 108617 A ailable online 4 Janua y 2024 0272-7714/© 2024 The Au ho s. Published by Else ie L d. This is an open access a icle unde he CC BY license (h p://c ea i ecommons.o g/licenses/by/4.0/). Mo phome ic a ia ions o wo pa ellid limpe s be ween a i icial b eakwa e s and na u al ee s Juan Sempe e-Val e de a , * , En ique Os al´ e-Val ibe as a , F ee Espinosa a , Fede ico M´ a quez b , c a Labo a o io de Biología Ma ina/Es aci´ on de Biología Ma ina Del Es echo (Ceu a), Depa amen o de Zoología, Facul ad de Biología, Uni e sidad de Se illa, A da. Reina Me cedes s/n, 41012, Se illa, Spain b Ins i u o de Biología de O ganismos Ma inos (IBIOMAR) - CONICET, Boule a d B own 2915, U9120ACF, Pue o Mad yn, Chubu , A gen ina c Uni e sidad Nacional de La Pa agonia San Juan Bosco, Boule a d B own 3051, U9120ACD, Pue o Mad yn, Chubu , A gen ina ARTICLE INFO Keywo ds: Gas opoda Pa ellidae Geome ic mo phome ics Coas al u baniza ion In e idal ABSTRACT A i icial sho elines o en di e om na u al ee s in shape, composi ion, and habi a complexi y. They p omo e highe accumula ion o pollu an s and inc eased physiological s ess, which lead o changes in species dis i- bu ions and ecosys em unc ioning. This can p omo e ophic shi s and educed gene ic di e si y o gas opod popula ions inhabi ing a i icial sho elines and migh p omo e mo phological changes, which may in luence beha iou , ulne abili y o p eda ion, eeding e iciency, sex a ios, ep oduc i e de elopmen , and o e all i ness. This s udy explo es in e - and in aspeci ic shell mo phome ic a ia ions in Pa ella us ica and P. cae ulea be ween b eakwa e s ( ip aps) and na u al ee s in h ee si es o Ceu a (No h A ica, Spain), including a physicochemical assessmen o he s udied loca ions: sho e o ien a ion, inclina ion and wa e exposu e, and subs a um na u e, he e ogenei y and oughness. Limpe s on a i icial subs a a had a sligh ly smalle ex a- isce al ca i y and la ened shell p o ile, which sugges s ha he desicca ion and empe a u e s ess d i en by he li hological composi ion and oughness o he s udied subs a a migh ha e in luenced he egis e ed shell shape a ia ion. Howe e , he high mo phome ic a ia ion egis e ed o bo h species ac oss si es and subs a a sugges s ha limpe s’ mo phology migh be esponding o a complex in e ac ion o en i onmen al and ecological ac o s a he han solely ock ype. The indings o his s udy highligh he complex in e play be ween ock ype and local en i onmen al condi ions in shaping pa ellid limpe s’ shell mo phology and p o ide insigh s in o he adap i e mechanisms ha d i e shell shape a ia ion in limpe popula ions in he ace o coas al sp awl and an h opogenic global change. 1. In oduc ion Coas al sp awl has d ama ically al e ed in e idal ecosys ems wo ldwide, esul ing in changes in species dis ibu ions, communi y s uc u e and ecosys em unc ioning (Connell and Glasby, 1999; Sei z e al., 2006; Bishop e al., 2017; Masucci and Reime , 2019). A i icial s uc u es a e poo su oga es o na u al ecosys ems and o en lack spa ial he e ogenei y a di e se spa ial scales, causing an o e all educ ion in habi a complexi y (Moschella e al., 2005; Fi h e al., 2015; Cacabelos e al., 2018; Os al´ e-Val ibe as e al., 2018). A he in e idal le el, su ace o ien a ion, inclina ion and he e ogenei y de e mine he composi ion o he communi y and can de e mine he a ailabili y o e uge agains desicca ion and empe a u e s ess, as well as g azing and p eda ion p essu e (Mo ei a e al., 2006; Bulle i and Chapman, 2010; Aguile a e al., 2019; Ams u z e al., 2021). Mo eo e , oughness, along wi h o he subs a um cha ac e is ics, such as colou , shape, pH and li hology, could in luence species se lemen and he physical s ess expe ienced by he communi ies inhabi ing ocky su - aces (Ri e a-Ing aham e al., 2013; Hanlon e al., 2018; Sempe - e-Val e de e al., 2023). Fu he mo e, aunal popula ions inhabi ing a i icial ha d subs a a can show highe accumula ion o hea y me als and o he pollu an s, highe s ess le els, shi s in he ophic niche and a educed gene ic di e si y when compa ed o na u al habi a s (Sedano e al., 2020a, 2020c; Sei z e al., 2006; Espinosa e al., 2021). Due o hese cons ain s, many local na i e species ha e ouble colonizing a i icial subs a a, which can lead o al e ed popula ion s uc u e and educed geno ypic and pheno ypic di e si y o ma ine o ganisms, p o- mo ing he agmen a ion o na i e species popula ions and con ibu ing * Co esponding au ho . E-mail add ess: [email p o ec ed] (J. Sempe e-Val e de). Con en s lis s a ailable a ScienceDi ec Es ua ine, Coas al and Shel Science jou nal homepage: www.else ie .com/loca e/ecss h ps://doi.o g/10.1016/j.ecss.2024.108617 Recei ed 3 June 2023; Recei ed in e ised o m 26 Decembe 2023; Accep ed 3 Janua y 2024 Es ua ine, Coas al and Shel Science 297 (2024) 108617 2 o he loss o coas al biodi e si y (Fau elo e al., 2009, 2012; Fi h e al., 2013, 2016; Bishop e al., 2017; Al e e al., 2020). Limpe s a e common inhabi an s o in e idal habi a s and play impo an ecological oles in ocky in e idal communi ies as p ima y consume s and ecosys em enginee s, in luencing ecosys em dynamics (Bu gos-Rubio e al., 2015). Due o hei ecological impo ance and abili y o espond o changes in habi a s uc u e, limpe s ha e been widely s udied in he con ex o coas al u baniza ion and a i icial subs a a (e.g., Espinosa e al., 2009, 2011, 2021; Fau elo e al., 2009; Chapman and Unde wood, 2011). Al hough coas al s uc u es always ha e a nega i e ecological impac because hey eplace na u al habi a s, he in oduc ion o seawalls, b eakwa e s and je ies can ha e bo h posi i e and nega i e e ec s on limpe popula ions (e.g., Mo ei a e al., 2006; Ri e a-Ing aham e al., 2011a; Bonnici e al., 2013; Cacabelos e al., 2016). A i icial subs a a p o ide colonizable su aces ha migh sus ain high densi y o limpe s, leading o inc eased popula ion numbe s o ce ain limpe species (Ri e a-Ing aham e al., 2011a; Bonnici e al., 2013; Os al´ e-Val ibe as e al., 2023). Howe e , a i icial sho elines can also p o ide low-quali y habi a s, lacking e ugia, causing ophic shi s and a ou ing non-indigenous species, which can nega i ely impac na i e limpe s ep oduc i e po en ial o he ex en o no being able o sus ain iable limpe s’ popula ions (Bu gos-Rubio e al., 2015; Sedano e al., 2020a; Espinosa e al., 2021; B anch e al., 2023; Ea p e al., 2023). Mo eo e , a i icial subs a a can lead o educed gene ic di- e si y wi hin limpe s’ popula ions and an inc eased gene ic di e en- ia ion om popula ions in na u al a eas, which sugges s ha a i icial habi a s may selec o dis inc and na owe ange o geno ypic ai s han na u al a eas (Fau elo e al., 2009, 2012). This would ha e conse a ional implica ions, as hese limpe s could be less esis an o en i onmen al s esso s and ecological impac s. None heless, his educed gene ic di e si y and inc eased di e en ia ion could also be due o a ounde e ec , as he popula ions migh be s ill se ling on he ecen ly deployed a i icial habi a (Bishop e al., 2017 and e e ences he ein). In any case, he e ec s o subs a um ype and shape on limpe popula ions a e complex and con ex -dependen , and u he esea ch is needed o be e unde s and hese e ec s and o de elop e ec i e managemen s a egies o conse ing limpe popula ions in u banized coas al en i onmen s (Lima e al., 2016; Sedano e al., 2020a, 2020b; Espinosa e al., 2011, 2021; Fau elo e al., 2012; Os al´ e-Val ibe as e al., 2022). Gas opod shells a e widely used as indica o s o en i onmen al changes in ma ine ecosys ems, and limpe s’ shell pa ame e s, such as heigh , hickness, and leng h, can be nega i ely a ec ed by pollu ion s ess (Nakhle, 2003; M´ a quez e al., 2011, 2017; Gha ed e al., 2019; Ha ayashiki e al., 2020; Land o e al., 2021). The e o e, he analysis o shell shape can p o ide aluable insigh s in o he o e all heal h o ma ine ecosys ems and he impac o abio ic and bio ic s esso s, such as u ban p oximi y (Doyle e al., 2022; Mal se a e al., 2022). O e all, limpe s’ shell shape is de e mined by an in e play o gene ic and en i- onmen al ac o s (Ba elli, 2016; Nu˜ nez e al., 2018; Nu˜ nez and Fe n´ andez I ia e, 2022), and limpe s’ shells a e cha ac e ized by high pheno ypical plas ici y in shape, which has been linked o habi a adap a ion (Puig, 2016; Bouzaza and Mezali, 2018, 2019; Eche e y e al., 2020; Vasconcelos e al., 2021; Belmokh a e al., 2022). Fo example, limpe s in highe idal le els and wa me la i udes end o ha e a alle shell p o ile, which educes desicca ion and empe a u e s ess by educing hea ans e om sunligh adia ion and conduc ion wi h he subs a e (Ve meij, 1973; P usina, 2013). Simila ly, a mo e cen ed shell apex and ci cula base inc ease adhesion s eng h o he subs a e and could be an adap a ion o a eas wi h high wa e ac ion (Denny and Blanche e, 2000; Paulo Cab al, 2007; Bouzaza and Mezali, 2019). Va ying u baniza ion p essu e can also impac limpe s shell shape (Gha ed e al., 2019; Land o e al., 2021). Fo example, Tablado and Gappa (2001) desc ibed bigge panpulmona e limpe s wi h highe shell p o iles inside a ha bou han nea by habi a s exposed o wa e ac ion. I was hypo hesized ha he di e ences in size could be due o he a ailabili y o longe o aging pe iods due o he absence o wa e dis u bance inside he po . Simila ly, Land o e al. (2021) and Nu˜ nez e al. (2012) ound his ological al e a ions, shells wi h globula mal- o ma ions, dec eased shell hickness and ha dness, and a alle shell p o ile in a eas unde an h opogenic impac . In addi ion, he alle shell p o iles de ec ed inside ha bou s in hese s udies migh be a esponse o lowe wa e ac ion o o di e ences in subs a um o ien a ion and o he en i onmen al pa ame e s o ele ance o limpe s ha could ha e di e ed be ween he s udied loca ions (Tablado and Gappa, 2001; Seab a e al., 2011; Nu˜ nez e al., 2012; Land o e al., 2021). Howe e , mo e esea ch is needed o unde s and he adap a ion o limpe s o di e en habi a s and how subs a um ype can in luence limpe s’ mo phology. Geome ic mo phome ics can p o ide mo e insigh in o complex shape a ia ion han classical echniques (Zeldi ch e al., 2012). Geo- me ic mo phome ics uses mul i a ia e me hods o iden i y sub le shape a ia ions be ween popula ions and species by he analysis o in ica e de ails, like cu a u e and sculp u e pa e ns, which could help seg ega e species o unde s and ecological adap a ions (Fa ia e al., 2017; Ma os e al., 2020; Mame e al., 2021). Using geome ic mo - phome ics, his s udy aims o explo e mo phome ic a ia ions in limpe shell shape be ween a i icial and na u al subs a a in di e en si es o Ceu a (N A ica, Spain) and he possible in luence o a se ies o physicochemical a iables in he obse ed shell shape pa e ns. To his end, he ollowing al e na i e hypo heses ha e been es ed. H1: he shell shape o P. us ica and P. cae ulea a y be ween a i icial b eakwa e s ( ip aps) and na u al ocky ee s; H2: his shell a ia ion has he same change di ec ion in di e en si es wi hin he a ea o s udy; and H3: he shell o m (shape +size) a ia ion egis e ed among si es and be ween subs a a is coinciden wi h di e ences in physicochemical pa ame e s ela ed o subs a um ype, wa e exposu e and spa ial con igu a ion o he s udied si es and subs a a. 2. Me hods 2.1. S udy a ea and species selec ion The S ai o Gib al a is a egion o high biodi e si y and ecological impo ance due o i s loca ion be ween biogeog aphical egions, making i key a ea o connec i i y o popula ions ha a e ulne able o impac s, and a p io i y a ea o conse a ion (Ri e a-Ing aham e al., 2013; Os al´ e-Val ibe as e al., 2022). Pa ella us ica and P. cae ulea a e wo common in e idal limpe species ha a e widely dis ibu ed h oughou he Medi e anean Sea and he NE A lan ic Ocean. In Ceu a (S ai o Gib al a ), limpe species ha e been ound in g ea e densi ies on a i- icial han na u al subs a a (see Os al´ e-Val ibe as e al., 2018, 2022). This is due o a educed human collec ion p essu e ( enced o ha dly accessible), and highe sho eline he e ogenei y on a i icial han na u al sho elines (Espinosa e al., 2009; Ri e a-Ing aham e al., 2013; Os al´ e-Val ibe as e al., 2022, 2023). Su eys we e made in h ee Ceu a si es, each wi h dolomi ic lime- s one ip aps and na u al ocky sho es (less han 650 m apa ) (Fig. 1. A). The ip aps s udied in No h Bay, Cho illo, and Fuen ecaballos we e olde han 16 yea s and we e cons uc ed in 1935, 1988, and 2006, espec i ely (Os al´ e-Val ibe as e al., 2018). The e o e, a i icial sub- s a a a e expec ed o hos climax ben hic communi ies in e ms o species composi ion and ichness (Hawkins e al., 1983; Coombes, 2011; Dong e al., 2016). Addi ionally, hese subs a a a e an icipa ed o suppo ma u e limpe popula ions, as he a e age li espan o he s ud- ied species is less han 10 yea s (Espinosa e al., 2008; Hen iques e al., 2012; P usina e al., 2015). 2.2. En i onmen al s udy The physicochemical desc ip ion o he s udied a eas was ca ied ou in July 2022 by haphaza dly deploying wo ho izon al 10 m ansec s a J. Sempe e-Val e de e al. Es ua ine, Coas al and Shel Science 297 (2024) 108617 3 he uppe midli o al le el in each o he s udied si es and subs a a (Fig. 1. A). Subs a um inclina ion, he e ogenei y and oughness we e measu ed a each ansec . He e ogenei y was calcula ed by ho izon ally deploying a lexible measu ing ape along he uppe midli o al, ollowing he ock con ou (p o ile) along he whole leng h o he ansec (10 m linea dis ance). Roughness and inclina ion we e measu ed a he beginning, in he middle, and a he end o each an- sec . Roughness was measu ed ollowing he same me hod as he e o- genei y bu along h ee ho izon al 25 cm linea dis ance ansec s and using a p o ile gauge wi h 0.5 mm pins o ob ain he ock p o ile (F os e al., 2005). Bo h he e ogenei y and oughness indexes we e calcula ed by di iding he ob ained p o iles by he linea dis ance o he sampled ansec (see Ri e a-Ing aham e al., 2011b; Sedano e al., 2020b). Inclina ion was measu ed placing a 3 m s ick on he ocky sho e, pe pendicula o he sho eline and spanning om he in ali o al o he sup ali o al le el, o measu e he inclina ion angle o he s ick wi h a digi al clinome e . The chemical and li hological composi ion o each ansec ock was s udied by collec ing wo ock chips pe si e and subs a um. These we e used o con i m he dolomi ic na u e o he a i icial b eakwa e in he s udied a eas (see Os al´ e-Val ibe as e al., 2023) and he in o ma ion p o ided by he Geological and Mining Ins i u e o Spain, which iden- i ies he na u al ock in he a ea as mainly me amo phic, wi h as gneisses (bio i e schis s), migma i es and po phy i ic g ani oids a No h Bay, gneisses and migma i ic gneisses a Cho illo, and phylli es and de o med conglome a es a Fuen ecaballos (Pineda e al., 2013). Rock chips we e milled and used o calcula e he ock elemen al composi ion by X- ay luo escence (XRF) using an AXIOS spec ome e . Rock mine alogical composi ion was es ima ed by X- ay di ac ion (XRD) using a powde di ac ome e (B uke D8 Ad ance) equipped wi h a high empe a u e chambe (An on Paa XRK 900) and a as esponse/high sensi i i y de ec o (B uke Van ec 1) wi h adial Solle sli s (Val e de e al., 2015). Wa e exposu e and sho e aspec (o ien a ion) we e ob ained a each si e and subs a um wi h Google Ea h. Wa e exposu e was quan i ied using he Fe ch index, which has been success ully employed o p edic in e idal communi y pa e ns (e.g., Bu ows e al., 2008), and de i es om an a e age be ween he maximum and e ec i e e ch indices (Howes e al., 1994). E ec i e e ch (Fe) is calcula ed using he equa ion Fe =[∑(cos Өi) ×Fi]/∑cos Өi, wi h Өi ep esen ing angles be ween sho e-no mal and di ec ions 0◦, 45◦le , and 45◦ igh , and Fi as he dis ance in Km along he ele an ec o , wi h a limi alue o 1000 km con en ionally used o open ocean. Maximum e ch is he maximum Fi eco ded when calcula ing Fe. Finally, he wa e exposu e class o each coas line sec ion is de e mined based on i e ca ego ies: e y p o ec ed (Fe ch <1), P o ec ed (1–10), semi-p o ec ed (10–50), semi-exposed (50–500), and exposed (>500) (Howes e al., 1994; Te ´ on-Sigle e al., 2016). 2.3. Mo phome ic s udy Adul indi iduals o Pa ella us ica and P. cae ulea, wi h sizes anging om 1.5 o 4.0 cm (F enkiel, 1975; P usina, 2013), we e andomly collec ed in May 2022 om wo subs a a: a i icial limes one b eak- wa e s and na u al ock la s a h ee si es in Ceu a, S ai o Gib al a , Spain (Fig. 1. A). A each si e and subs a um, a o al o 25 indi iduals o each species we e collec ed om he uppe midli o al (P. cae ulea) and lowe sup ali o al (P. us ica) wi hin a 25 m ansec pa allel o he sho eline (50 indi iduals pe species and si e). Limpe s we e collec ed ensu ing ha hei shells we e no excessi ely e oded o he ex en o losing hei o iginal shape. A e collec ion, shells we e cleaned and pho og aphed om en al Fig. 1. A: S udy si es, indica ing he loca ion o he sampled a i icial and na u al subs a a in Ceu a (No h A ica, Spain). B: Landma ks (LM) and semi-landma ks (S-LM) con igu a ion o he la e al and en al iews depic ing he consensus shape o all sampled indi iduals. The la e al iew is a non-symme ic shape wi h LM1 loca ed a he on end, LM8 on he apex and LM15 a he back end o he shell. These LM a e espec i ely coinciden wi h he LM16, LM 4 and LM23 o he en al iew. The en al iew is a symme ical con igu a ion wi h he axis o symme y c ossing LM16 ( on o he shell), LM1 ( on o he head), LM4 (apex), LM10 (pos e io end o he hepa opanc ea ic ca i y) and LM23 (back end o he shell). This LM and S-LM con igu a ion was selec ed o e lec he shape con ou o he bo de o he shell and he bo de o he hepa opanc ea ic ca i y. J. Sempe e-Val e de e al. Es ua ine, Coas al and Shel Science 297 (2024) 108617 4 and la e al pe spec i es. The analysis o shell shape was pe o med using landma k-based (2D) geome ic mo phome ic echniques. The apex, shell ou line and hepa opanc ea ic ou lines we e cap u ed om he la e al iew using a non-symme ic con igu a ion wi h 3 landma ks and 22 semi-landma ks (Fig. 1B), and om he en al iew using a sym- me ic con igu a ion wi h 9 landma ks and 20 semi-landma ks (Fig. 1C). All specimens we e digi ized by he same obse e (JS-V) using TpsDig2 .2.17. The semi-landma ks used o cap u e con ou s we e laye ed e enly along con ou cu es be ween landma ks and we e homologa ed ma hema ically in an i e a i e p ocess (sliding) using TpsRelw .1.53. In his me hod, he S-LM coo dina es a e slid along he con ou o minimize he bending ene gy o he landma k con igu a ion (Slice, 2005). Then, a gene alized P oc us es analysis was applied in which landma k con ig- u a ions we e o a ed, ansla ed o a common o igin, and scaled o a uni a y cen oid size o ob ain he P oc us es aligned coo dina es, used as shape da a (Rohl and Slice, 1990). 2.4. S a is ical analyses Possible di e ences in shell size among si es and subs a a o P. us ica and P. cae ulea we e es ed using ANOVAs on cen oid size da a, a e explo ing he da a o no mali y wi h a Kolmogo o -Smi no es , and homoscedas ici y wi h a Le ene’s es . These analyses we e ca ied ou using IBM SPSS S a is ics 22. To accoun o allome y, mul i a ia e eg essions we e pe o med in Mo phoJ 1.06 b (Klingen- be g, 2011) o bo h species and each species sepa a ely (Zeldi ch e al., 2012). The e m “allome y,” was used as de ined by Mosimann (1970): he pa e n o co a ia ion among mo phological ai s o he ela ion- ship be ween shape and size componen s. Mo phoJ eg essions a e compu ed and plo ed a e D ake and Klingenbe g (2008), and o igi- na e om he eg ession equa ion y =xb +e, whe e y is he andom ec o o dependen a iables, which in ou case a e he shape a iables ep esen ed by he P oc us es coo dina es (la e al iew) and he sym- me ic componen ( en al iew), x is he andom ec o o independen a iables, which in ou case is he cen oid size (shell size), b is he ma ix o eg ession coe icien s, and e is he andom ec o o e o e ec s. The mul i a ia e eg ession sco es a e hen accoun ed wi h he a iable si =ybi T (bi T bi) −0.5 , o ob ain he shape sco e s, which is he shape a iable ha is mos s ongly associa ed wi h he i- h independen a iable (x i ) (see Klingenbe g, 2011). The s a is ical signi icance o he eg ession was es ed wi h a pe mu a ion es (10,000 ounds) agains he null hypo hesis o independence. The p esence o allome y was conside ed i he eg ession was signi ican (p- alue <0.05) and he eg ession coe icien highe han 5 %. In hese cases, he ec o o eg ession sco es compu ed by Mo phoJ o all he obse a ions in he sample was isualized along wi h he shape a ia ions ep esen ed by he mul iple eg ession, which we e plo ed by econs uc ing hypo- he ical o ms o a wi e ame connec ing landma ks (wi e ame plo ). Whene e p esen , allome y componen was elimina ed du ing u he analyses by wo king wi h he eg ession’s esiduals (Klingenbe g, 2016; Ou omu o and Johansson, 2017). Shape da a (PCsco es) was used o pe o m conglome a e o dina- ions on Mahalanobis dis ances among species, si es and subs a a using In oS a (Di Rienzo e al., 2020). Subsequen o dina ions and es s we e made wi h Mo phoJ so wa e, using Disc iminan Func ion Analyses wi h c oss alida ion o explo e a ia ion be ween wo g oups o ob- se a ions (species and subs a a) and Canonical Va ia e Analyses as a gene al analysis o ind he shape ea u es ha bes dis inguish among mul iple g oups o specimens ( a ia ion among si es) (Klingenbe g, 2011 and e e ences he ein). Disc iminan Func ion and Canonical Va ia e Analyses a e classical echniques o mul i a ia e s a is ics, and de ails can be ound in mos ex books o mul i a ia e s a is ics and mo phome ics (e.g., Rohl and Books ein, 1990; Timm, 2002). In mul i a ia e mo phome ics, hese a e used o iden i y shape compo- nen s ha maximize he di e ences in shape be ween and among g oup o obse a ions ha a e known a p io i (Viscosi and Ca dini, 2011). Fo he esul ing o dina ions, shape di e ences be ween g oup means and along canonical axes we e plo ed using wi e ame plo s. Following hese ou ines, di e ences be ween g oups we e analysed using pe - mu a ion es s (10,000 pe mu a ions) on P oc us es dis ances (Mahala- nobis dis ances) o calcula e he Ho elling T-squa e s a is ic o he null hypo hesis o equal g oup means. 3. Resul s 3.1. En i onmen al s udy The physicochemical cha ac e iza ion o he sampling a eas high- ligh ed a highe mac oscale he e ogenei y and su ace oughness o a i icial subs a a wi hin all si es, excep o oughness in Fuen eca- ballos (Table 1). O e all, sho e aspec was simila o he a i icial and na u al a eas o each si e. A No h Bay and Fuen ecaballos, na u al sho es we e sligh ly s eepe han a i icial sho es; in con as a Cho illo he a i icial sho e was much s eepe . Fu he mo e, all si es and sub- s a a we e semi-exposed acco ding o Fe ch index classi ica ion, al hough he si es acing sou h, pa icula ly Cho illo, we e he mos wa e exposed si e while No h Bay si e was he leas exposed one. Finally, subs a a had di e en elemen s and li hological composi ion, wi h a i icial subs a a being dolomi ic ip ap ocks, and na u al ocks showing he p o ile o g aphi e, qua z and musco i e- ich me amo phic ocks (Supplemen a y Table 1). 3.2. Mo phome ic s udy No indi iduals o Pa ella cae ulea we e ound on he na u al sub- s a um in No h Bay, so he mo phome ic s udy was ca ied ou wi h a o al o 275 indi iduals. The cen oid sizes o P. us ica and P. cae ulea ollowed a no mal dis ibu ion o all si es and subs a a (Kolmogo o - Smi no : P >0.05 in all es ou pu s) and we e homoscedas ic (Le ene: P. us ica: F 5,269 =0.57; P =0.722; P. cae ulea: F 4,269 =1.75; P =0.143). No di e ences in cen oid size we e ound be ween subs a a o P. us ica (ANOVA: MS =0.85; F 1,269 =2.31; P =0.131) and P. cae ulea (MS =0.16; F 1,269 =0.40; P =0.527) and among si es o P. cae ulea (MS =1.01; F 2,269 =2.55; P =0.082). Howe e , cen oid size was highe in No h Bay han Fuen ecaballos and Cho illo o P. us ica (MS =6.88; F 2,269 =18.65; P <0.001) (see means and s anda d de ia ions a Sup- plemen a y Table 2). Allome ic changes in shell shape p edic ed less han 5 % o he o e all shape a ia ion when conside ing bo h species (Table 2). How- e e , when conside ing species sepa a ely, allome ic shell g ow h occu ed in P. us ica la e al iew, wi h shell heigh inc easing mo e apidly han leng h as size inc eased, and he en al con ou o P. cae ulea, in which he inne con ou g ew mo e apidly a ound he body han he head (Table 2; Supplemen a y Fig. 1). The e o e, allom- e y was conside ed p esen o P. us ica la e al iew and P. cae ulea en al iew and subsequen analyses we e ca ied ou wi h he e- siduals o hese eg essions, conside ed as new size-un ela ed shell shape a iables. O e all, di e ences in shape be ween species we e highe han hei in aspeci ic a ia ion o bo h la e al and en al iews, and highe o he la e al han he en al iew (see Fig. 2). On he la e al iew, he mean shell shape o P. us ica is mo e conical, wi h he shell less p o- jec ed on an e io -pos e io axis, and mo e p ojec ed apex along he do sal- en al axis, han P. cae ulea (Disc iminan Func ion Analysis: N =275; Mahalanobis dis ance =4.28; T-squa e =1248.5; P (pe m) < 0.001; see Supplemen a y Table 3; Supplemen a y Fig. 2). On he en al iew, he shell con ou o P. us ica was gene ally ounde , while P. cae ulea had a mo e pen agonal shell con ou shape, and he inne hepa opanc ea ic con ou was sligh ly ounde , and he apex mo e displacemen o he pos e io pa in P. us ica han P. cae ulea (N =275; Mahalanobis dis ance =2.98; T-squa e =757.7; P (pe m) <0.001; see Supplemen a y Table 3; Supplemen a y Fig. 2). J. Sempe e-Val e de e al. Es ua ine, Coas al and Shel Science 297 (2024) 108617 5 Table 1 Resul s o he en i onmen al a iables measu ed in each sampled loca ion. * Rock ype was in e ed om he li hological esul s included a Supplemen a y Table 1. Cell shading in he able is indica i e o cell alues, wi h da ke shading applied o highe alues. Si e No h Bay Cho illo Fuen ecaballos Subs a um A i icial Na u al A i icial Na u al A i icial Na u al He e ogenei y 1.53 1.17 1.59 1.25 1.28 1.23 Roughness 32.80 29.60 32.41 31.17 31.37 31.78 Inclina ion 17.41ᵒ 21.11ᵒ 21.14ᵒ 13.44ᵒ 16.36ᵒ 18.79ᵒ Fe ch index 71.46 54.49 203.13 213.42 99.11 176.29 Sho e aspec N NW S S SE S Rock ype* Dolomi e G aphi e Dolomi e Qua z-musco i e Dolomi e Musco i e Table 2 Reg essions esul s be ween cen oid size as shell size (p edic o a iable), and he P oc us es coo dina es (la e al iew) and symme ic componen ( en al iew) as shape a iables ( esponse a iables) o accoun o allome y, o all specimens (N =275) and o each species sepa a ely: Pa ella us ica (n =150) and P. cae ulea (n = 125). SS =To al squa e sum; Residual =Residual squa e sum; % p ed = eg ession coe icien . Bold alues indica e he cases in which allome y is accep ed (signi ican P- alue and a eg ession coe icien highe han 5 %). La e al iew Ven al iew SS Residual % p ed P- alue SS Residual % p ed P- alue All specimens 0.970 0.945 2.53 <0.001 0.536 0.511 4.79 <0.001 P. us ica 0.477 0.427 10.52 <0.001 0.243 0.235 3.43 <0.001 P. cae ulea 0.357 0.346 3.17 0.010 0.233 0.220 5.76 <0.001 Fig. 2. Conglome a e o dina ions depic ing he Mahalanobis a e age dis ances among he sampling loca ions o all indi iduals (P. us ica and P. cae ulea) using he la e al and en al iews shape da a. The wi e ames o he consensus shapes a e included o P. us ica and P. cae ulea along wi h hei espec i e sample g oups. J. Sempe e-Val e de e al. Es ua ine, Coas al and Shel Science 297 (2024) 108617 6 Table 3 Canonical Va ia e Analysis (CVA) on P oc us es coo dina es, showing Mahalanobis dis ances (Md) and P- alues om pe mu a ion es s (P (pe m)) be ween pai s o si es o he la e al and en al iews o P. us ica and P. cae ulea. NB =No h Bay; Ch =Cho illo; Fc =Fuen ecaballos. La e al iew Ven al iew Pa ella us ica Pa ella cae ulea Pa ella us ica Pa ella cae ulea Md P (pe m) Md P (pe m) Md P (pe m) Md P (pe m) NB s. Ch 2.01 <0.001 2.68 <0.001 1.84 <0.001 2.22 <0.001 NB s. Fc 1.88 <0.001 3.63 <0.001 2.08 <0.001 2.79 <0.001 Ch s. Fc 2.01 <0.001 1.80 <0.001 2.12 <0.001 1.95 <0.001 Table 4 Disc iminan analyses on P oc us es coo dina es be ween subs a a (a i icial s. na u al) o he la e al and en al iews o Pa ella us ica and P. cae ulea. M-dis ance =Mahalanobis dis ance; T-squa e =Ho elling’s -s a is ic; P (pe m) =P- alues om pe mu a ion es s. La e al iew Ven al iew Mahalanobis dis ance Ho elling’s -s a is ic P (pe m) Mahalanobis dis ance Ho elling’s -s a is ic P (pe m) P. us ica 2.05 158.22 <0.001 1.44 77.54 0.001 P. cae ulea 2.03 123.35 0.012 1.48 65.29 0.011 Fig. 3. Canonical Va ia e Analyses (CVAs) on P oc us es coo dina es among si es o he la e al iew o P. us ica (A) and P. cae ulea (B) and he en al iew o P. us ica (C) and P. cae ulea (D). The colou ed ci cum e ences in he CVAs ep esen 95 % con idence ellipses o he a e age o each si e. The wi e ame diag ams show he a ia ion ob ained in each CVA axis, showing bo h he posi i e and nega i e di ec ion o he de o ma ion, wi h a scale ac o o ±4. Ligh blue indica es he consensus shape, while da k blue indica es he ±shape ex eme a ia ions. (Fo in e p e a ion o he e e ences o colou in his igu e legend, he eade is e e ed o he Web e sion o his a icle.) J. Sempe e-Val e de e al. Es ua ine, Coas al and Shel Science 297 (2024) 108617 7 Mahalanobis dis ances among indi iduals e ealed in aspeci ic di e ences among si es and subs a a o bo h s udied species (Table 3; Table 4). O e all, indi iduals had a speci ic shell shape a each si e. These di e ences occu ed o he la e al iew in he posi ion o he apex, which was close o he cen e o he shell a he si es in Sou h Bay: Cho illo and Fuen ecaballos, and mo e displaced o he on o he animal in No h Bay o bo h P. us ica (Fig. 3. A) and P. cae ulea (Fig. 3. B). F om he en al iew, he ela i e size o he hepa opanc ea ic con ou a ound he head was smalle in Fuen ecaballos and bigge in Cho illo o bo h species (Fig. 3. C and D). In P. cae ulea, he en al shape a ied om a ounde shell pe ime e and elonga ed hep- a opanc ea ic con ou in No h Bay o a mo e pen agonal ou e shell pe ime e and mo e globula inne con ou in Fuen ecaballos (Fig. 3. D). Shell shape a ied be ween a i icial and na u al subs a a o P. us ica and P. cae ulea (Table 4), al hough his a ia ion was gene ally small and only P. us ica en al iew showed a clea dis inc ion be ween subs a a (Table 5). None heless, bo h species showed a simila shell shape a ia ion be ween subs a a (Fig. 4). Fo he en al iew, P. us ica had a wide hepa opanc ea ic con ou (inne con ou ) a ound he head and na owe a ound he body, which leaded o a wide space be ween he oo and he con ou o he shell in na u al han a i icial subs a a (Fig. 4). Fo he la e al iew, P. us ica showed a highe shell in na u al han a i icial subs a a. Seemingly, he ela ion be ween he hepa opanc ea ic con ou a ound he body and he ou e shell p o ile (ou e con ou ) was also smalle and he la e al shell p o ile was sligh ly highe in na u al han a i icial subs a a o P. cae ulea (Fig. 4), which also leaded o a wide gap be ween he oo and he ou e shell con ou in na u al han a i icial subs a a. 4. Discussion A consis en mo phological di e ences be ween a i icial and na u al subs a a o bo h s udied species and ac oss si es (hypo heses H1 and H2) sugges s ha he e is a common ac o in luencing shell mo phology ha seg ega es popula ions om na u al e sus a i icial subs a a. In he p esen s udy, ock li hology, he e ogenei y and oughness we e he en i onmen al pa ame e s ha mo e clea ly seg ega ed na u al and a i icial subs a a and could ha e in luenced he obse ed di e ences in shell mo phology (H3). These ac o s can in luence he abundance and popula ion s uc u e o pa ellid limpe s, pa icula ly when compa ing a i icial and na u al subs a a (Espinosa e al., 2011; Ri e a-Ing aham e al., 2011a; Ba elli, 2016; Cacabelos e al., 2016; Os al´ e-Val ibe as e al., 2023). Ne e heless, ock ype has a seconda y ole in s uc u ing ben hic communi ies (Cacabelos e al., 2016, 2019; Sempe e-Val e de e al., 2023). I s e ec s on limpe s’ mo phology a e s ill poo ly unde - s ood, and some au ho s ound no di e ences in shell leng h and heigh when compa ing di e en subs a a (Ba elli, 2016; Ame e al., 2018). In his s udy, he a i icial subs a a (limes one boulde s) could be p omo ing a lowe desicca ion s ess han he na u al me amo phic ocks. Fi s , because he highe he e ogenei y o a i icial subs a a (10 m scale) sugges s ha ip aps could ha e mo e nooks and c annies, shadowed a eas ha limpe s migh be using o amelio a e desicca ion and empe a u e s ess du ing low ide (P usina, 2013; Fi h e al., 2015). Second, because a highe he e ogenei y o he subs a um su ace a small scales (e.g., oughness) allows less hea ing and mo e wa e e en ion du ing low ide, e en hough he e ogenei y in he ield exis s on many scales besides hose es ed in he p esen s udy (Aguile a e al., 2019; Sempe e-Val e de e al., 2023; Amb ose e al., 2021). Thi d, because he di e ences in ock li hology de e mine hei wea he ing a es, oughness, shape, ex u e, we abili y and albedo, and can in u n in luence desicca ion s ess du ing low ide (Sempe e-Val e de e al., 2023 and e e ences he ein). Roughness di e ences a e due in pa o ock mine ology and e osional his o y, o which in e ene biological wea he ing coupled wi h bioe osion by endoli hic algae bo e in o calca eous subs a a h ough chemical p ocesses (Sch¨ onbe g and Wis- shak, 2014; Sempe e-Val e de e al., 2018; Amb ose e al., 2021). This migh ha e con ibu ed o an inc eased oughness o he s udied calca eous ock in a mic oscopic scale and migh p o ide an addi ional eeding esou ce o g azing o ganisms, in addi ion o mic obial ilms on he su ace (Hills and Hawkins, 1991), mac o-algae (Della San ina e al., 1993) and mac o-algal de i us (No man e al., 2016). Mo eo e , calca eous ock ypes gene ally ha e a highe su ace ee ene gy han silica- ich ones, which esul s in a highe we ing (Callow and Fle che , 1994; Amb ose e al., 2021). Finally, he calca eous a i icial dolomi e was ligh e (highe albedo) han he na u al ocks in he s udied a eas (JS-V pe s. Obs.), which would imply lowe he mal abso p ion by he o me om sunligh . In conclusion, all hese ac o s could ha e con ibu ed o educe he he mal and desicca ion s ess expe ienced on a i icial subs a a, in luencing limpe s’ pheno ype. I is in e es ing o no e ha ea lie s udies ha e sugges ed ha a i icial subs a a could c ea e ho e and d ie condi ions compa ed o na u al subs a a (Aguile a e al., 2019). This migh be linked o he unique ea u es o he su aces examined in his s udy, as o he a i icial subs a a, such as conc e e, would no be as he e ogeneous as he s udied ip aps. Mo e- o e , na u al ock exhibi s signi ican geog aphical he e ogenei y, leading o a ange o en i onmen al condi ions, while a i icial sub- s a es end o show mo e uni o mi y ac oss loca ions when compa ed o na u al ock. The e o e, mo e esea ch on di e en subs a a and hei e ec s ac oss geog aphical scales would be needed be o e d awing conclusions abou he ecological e ec s o subs a um ype. Rega dless o he high spa ial and esidual a iabili y in Pa ella us- ica and P. cae ulea, which e lec s he high pheno ypical a iabili y o bo h s udied species (Belkhodja and Romdhane, 2012; P usina, 2013; Bouzaza and Mezali, 2018), he e was a common end by bo h species owa ds a sligh ly inc eased shell heigh and a na owe hep- a opanc ea ic con ou on na u al subs a a. These a e s a egies adop ed by limpe s agains he mal and desicca ion s ess (Ve meij, 1973; Ha ley e al., 2009). A alle shell has a smalle basal su ace a ea pe olume uni , which educes empe a u e ans e by conduc ion wi h he sub- s a um, educes he a ea exposed o sunligh adia ion, and migh in- c ease hea loss by con ec ion (Ha ley e al., 2009). I also educes he basal pe ime e o he shell, which in u n minimizes wa e loss h ough Table 5 Classi ica ion/misclassi ica ion ables o c oss alida ion o disc iminan unc ions be ween a i icial and na u al subs a a o Pa ella us ica (n =150) and P. cae ulea (n =125) la e al and en al iews. O igin Pa ella us ica La e al iew Pa ella us ica Ven al iew Alloca ed o Alloca ion accu acy Alloca ed o Alloca ion accu acy A i icial Na u al A i icial Na u al A i icial 52 23 69.3 % 56 19 74.7 % Na u al 31 44 58.7 % 18 57 76.0 % Pa ella cae ulea La e al iew Pa ella cae ulea Ven al iew A i icial 52 23 69.3 % 52 23 69.3 % Na u al 22 28 56.0 % 23 27 54.0 % J. Sempe e-Val e de e al. Es ua ine, Coas al and Shel Science 297 (2024) 108617 8 he bo de o he shell du ing low ide (Ve meij, 1973). Mo eo e , a highe shell implies a highe la e al a ea in ela ion o basal a ea, which in u ns inc eases he capaci y o he ex a- isce al ca i y (Ve meij, 1973). This ca i y is u he inc eased by a na owe hepa opanc ea ic con ou ha inc eases he gap be ween he oo and shell pe ime e and de e mines he amoun o wa e ha can be e ained a ound he oo du ing low ide (Ve meij, 1973; P usina, 2013). All his would help limpe s be e su i e empe a u e and desicca ion s ess in he in e - idal en i onmen (Ve meij, 1973; Paulo Cab al, 2007; Ha ley e al., 2009), indica ing ha a i icial subs a a ha e lowe empe a u es and hence desicca ion s ess han hose na u al subs a a in ou s udy. Ne e heless, subs a um ype had a clea seconda y ole in in luencing shell mo phology, since shell shape a ia ion is mos likely de e mined by adap a ion o he local en i onmen . In ield, en i onmen al condi ions a e de e mined by a complex in e ac ion o ac o s ha a y ac oss si es and loca ions, such as sho e aspec , inclina ion, local hy- d odynamics, wa e ac ion, limi ed esou ces a ailabili y (e.g., ood and e ugia), as well as pollu ion, collec ion, compe i ion and p eda ion p essu e (Denny and Blanche e, 2000; Tablado and Gappa, 2001; Ri - e a-Ing aham e al., 2011a; Ame e al., 2018; Bouzaza and Mezali, 2019; Vasconcelos e al., 2020; Espinosa e al., 2021; Os al´ e-Val ibe as e al., 2022, 2023). The e o e, u he s udies inco po a ing expe i- men al manipula ions would be necessa y o u he elucida e he un- de lying mechanisms d i ing pa e ns o shell a ia ion in limpe species. This s udy eco ded he mo pho ypes ha cha ac e ize P. us ica and P. cae ulea, he high in aspeci ic a iabili y in shell shape o hese species, and hei allome ic g ow h pa e ns (Belkhodja and Romdhane, Fig. 4. Disc iminan analyses on shell shape di e ences (P oc us es coo dina es) o he la e al and en al iews o P. us ica and P. cae ulea be ween na u al and a i icial subs a a. The wi e ame diag ams show he a ia ion ob ained along he disc iminan sco es, showing bo h he posi i e and nega i e di ec ion o he de o ma ion, wi h a scale ac o o ±3.0. The e o e, he da k blue wi e ame indica es a h ee- imes exagge a ed a e age shape on na u al subs a a, while he ligh blue indica es he same o a i icial subs a a. (Fo in e p e a ion o he e e ences o colou in his igu e legend, he eade is e e ed o he Web e sion o his a icle.) J. Sempe e-Val e de e al. Es ua ine, Coas al and Shel Science 297 (2024) 108617 9 2012; P usina, 2013; Puig, 2016; Bouzaza and Mezali, 2018). Among in e idal limpe s, he e is a well-known in e - and in aspeci ic inc ease in shell heigh /basal a ea a io wi h inc easing sho e le el (Ve meij, 1973; Paulo Cab al, 2007; Ri e a-Ing aham e al., 2011b). Howe e , hese changes can also occu h oughou he on ogene ic de elopmen o hese o ganisms. In he Medi e anean Sea, P. us ica shells exhibi allome ic shell g ow h, wi h heigh inc easing mo e apidly han leng h, o educe e apo a i e wa e loss (Paulo Cab al, 2007; P usina, 2013; Ame e al., 2018), and wi h he shell base becoming mo e ci cula and he apex becoming mo e cen ed (Bensaˆ ad-Bendjedid e al., 2022), which has been ela ed o a as e and s onge adhesion o he sub- s a um and migh be an adap a ion o a high hyd odynamic s ess en i onmen (Denny and Blanche e, 2000; Paulo Cab al, 2007; Bouzaza and Mezali, 2019). The same allome ic g ow h, wi h he shell base becoming mo e ci cula and he apex becoming mo e cen ed, was ound o P. cae ulea in his s udy. In P. cae ulea, Boukhicha e al. (2010) desc ibed an allome ic inc ease in shell heigh , which along wi h a ounde basis would help o igh desicca ion s ess (Paulo Cab al, 2007). Finally, Boukhicha e al. (2010) desc ibed an allome ic inc ease in adula leng h in P. cae ulea, which has also been p oposed as an adap a ion o g azing highe sho e le els, whe e algae a e less abundan and mo e equen ly enc us ing (Paulo Cab al, 2007; Boukhicha e al., 2010). Finally, his allome ic g ow h migh as well be accompanied by a displacemen o he home-sca o uppe li o al le els, which a e o en inhabi ed by g ea e indi iduals o P. Rus ica in he s udy a ea, while he small indi iduals a e usually in lowe idal le els (JS-V Pe s. Obs.). This shi in sho e le el be ween ju eniles and adul s occu s in o he species, and i is equen o ind ju eniles o limpe s occupying di e en niches, such as idepools and lowe sho e le els, han hose inhabi ed by adul s (Ri e a-Ing aham e al., 2011b; Espinosa and Ri e a-Ing aham, 2017; Li o e e al., 2018; Seab a e al., 2020, 2023). None heless, isome ic g ow h and a nega i e allome ic adula g ow h has also been eco ded o P. us ica in he colde clima e o NE A lan ic Po ugal (Paulo Cab al, 2007), whe e he he mal and desicca ion s ess migh be a less de e - minan ac o o su i al. 5. Conclusion Ou s udy highligh s he complex in e play be ween ock ype and local en i onmen al condi ions in shaping he mo phology o pa ellid limpe s and p o ide insigh s in o he adap i e mechanisms ha d i e shell shape a ia ion in limpe popula ions on subs a a di e ing in he e ogenei y, oughness and li hology. Coas al sp awl migh ha e b oad ecological and e olu iona y implica ions on in e idal g aze s, and i is impo an o unde s and he ecological impac s o coas al de elopmen on coas al ecosys ems and in he abili y o limpe s o espond and adap o changing en i onmen al condi ions (Espinosa and Ri e a-Ing aham, 2017). The e o e, u he esea ch inco po a ing expe imen al manipula ions, such as Vasconcelos e al. (2021), is needed o be e unde s and he complex na u e o limpe s’ mo pho- logical esponses o en i onmen al condi ions. Gi en ha a i icial subs a a migh p omo e popula ion isola ion and igge selec i e p essu es in he long e m, wi h di e en popula ions adap ing o spe- ci ic subs a um cha ac e is ics (Nakano and Ozawa, 2005; Fau elo e al., 2009; Ri e a-Ing aham e al., 2011b; Sedano e al., 2020b; Espi- nosa e al., 2021), his s udy unde sco es he need o unde s anding he mechanisms ha d i e and main ain pheno ypical and geno ypical di- e si y as a basis o conse ing such popula ions. Finally, he posi i e impac o a i icial s uc u es on limpe popula ions in his case s udy and o he s in he s udied a ea, such as Ri e a-Ing aham e al. (2011b), Ga cía-G´ omez e al. (2014), and Os al´ e-Val ibe as e al. (2022, 2023), a e geog aphically and s uc u e- ype (dolomi ic b eakwa e ) con ex speci ic, and hey mus no be used o ad oca e deploymen o a i icial subs a a (Fi h e al., 2020). Ac ually, coas al sp awl can ha e an o e all nega i e impac on na i e biodi e si y and may esul in uni o m selec ion p essu es ha nega i ely impac he limpe popula ions inhabi ing hem (Mo ei a, 2006; Mo ei a e al., 2006; Fau elo e al., 2009, 2012; Bulle i and Chapman, 2010; Bu gos-Rubio e al., 2015; Bishop e al., 2017; Sedano e al., 2020a; Al e e al., 2020; Espinosa e al., 2021). In he S ai o Gib al a he e a e some bene i s o a i icial s uc u es o limpe popula ions and conse a ion o a e and endan- ge ed species (REF), bu his is unlikely o always be he case. CRediT au ho ship con ibu ion s a emen Juan Sempe e-Val e de: W i ing – o iginal d a , Visualiza ion, Fo mal analysis, Da a cu a ion. En ique Os al´ e-Val ibe as: W i ing – e iew & edi ing, Resou ces, Me hodology, In es iga ion, Funding acquisi ion. F ee Espinosa: W i ing – e iew & edi ing, Valida ion, Supe ision, P ojec adminis a ion, In es iga ion, Funding acquisi ion, Concep ualiza ion. Fede ico M´ a quez: W i ing – e iew & edi ing, Valida ion, Supe ision, So wa e, P ojec adminis a ion, Me hodology, In es iga ion, Funding acquisi ion, Fo mal analysis, Da a cu a ion, Concep ualiza ion. Decla a ion o compe ing in e es The au ho s decla e ha hey ha e no known compe ing inancial in e es s o pe sonal ela ionships ha could ha e appea ed o in luence he wo k epo ed in his pape . Da a a ailabili y Da a will be a ailable a he Uni e siy o Se ille deposi o y (h ps://idus.us.es/) Acknowledgemen s We a e e y g a e ul o Ma kos Digenis o helping wi h he ield wo k and o he anonymous e iewe s o hei aluable commen s o- wa ds he imp o emen o he manusc ip . JSV was suppo ed by a FPI G an (PRE 2018-086266) om Minis e io de Ciencia, Inno aci´ on y Uni e sidades (P ojec CGL 2017-82739-P) co- inanced by ERDF Eu o- pean Union and Agencia Es a al de In es igaci´ on, Gobie no de Espa˜ na. Appendix A. Supplemen a y da a Supplemen a y da a o his a icle can be ound online a h ps://doi. o g/10.1016/j.ecss.2024.108617. Re e ences Aguile a, M.A., A ias, R.M., Manzu , T., 2019. Mapping mic ohabi a he mal pa e ns in a i icial b eakwa e s: al e a ion o in e idal biodi e si y by highe ock empe a u e. Ecol. E ol. 9 (22), 12915–12927. h ps://doi.o g/10.1002/ece3.5776. Al e , S.E., Ta iq, L., C eed, J.K., Mega u, E., 2020. E olu iona y esponses o ma ine o ganisms o u banized seascapes. E olu iona y Appl. 14, 210–232. h ps://doi.o g/ 10.1111/e a.13048. Amb ose J ., W.G., Renaud, P.E., Adle , D.C., Vadas, R.L., 2021. Na u ally occu ing ock ype in luences he se lemen o ucus spi alis L. Zygo es. J. Ma . Sci. Eng. 9 (9), 927. h ps://doi.o g/10.3390/jmse9090927. Ame , L.A.M., Benali, I., De meche, S., Boude bala, M., 2018. Seasonal a ia ions o he biome ic indices o Pa ella us ica Linnaeus, 1758 (Gas opoda Pa ellidae) om con as ed si es o he wes e n Alge ian coas . Biodi e si y J. 9 (3), 205–212. h ps://doi.o g/10.31396/Biodi .Jou .2018.9.3.205.212. Ams u z, A., Fi h, L.B., Spice , J.I., Hanley, M.E., 2021. Facing up o clima e change: communi y composi ion a ies wi h aspec and su ace empe a u e in he ocky in e idal. Ma . En i on. Res. 172, 105482 h ps://doi.o g/10.1016/j. ma en es.2021.105482. Ba elli, C., 2016. Mo phome ic cha ac e is ics, e ical dis ibu ion and densi y o he limpe Pa ella cae ulea L. In ela ion o di e en subs a a o he Bay o Kope (Gul o T ies e, No he n Ad ia ic). Annals o Is ian and Medi e anean S ud. 26 (2), 145–156. h ps://doi.o g/10.19233/ASHN.2016.13. Belkhodja, H., Romdhane, M.S., 2012. E ude mo phome ique du Mollusque gas e opode Pa ella cae ulea linnaeus, 1758 des co es no d de la Tunisie. Bull. de l’Ins i u Na l. des Sci. e Technol. Me de Salammbˆ o 39, 15–23. Belmokh a , F., Belmokh a , R., Ke ou , A., Hamed, M.B.B., 2022. Mo phome ic analysis o h ee medi e anean limpe s Pa ella cae ulea linnaeus, 1758, P. us ica J. Sempe e-Val e de e al.