Komparativna analiza morfometrijskih značajki vrsta riječni rak (Astacus astacus) i uskoškari rak (Astacus leptodactylus)

master's thesis

• Title (english): Comparative analysis of morphometric characteristics of noble crayfish (Astacus astacus)) and narrow-clawed crayfish (Astacus leptodactylus)
• Author: Ivan Špelić
• Mentor: Ivana Maguire (mentor)
• Committee member: Ivana Maguire (predsjednik povjerenstva)
• Committee member: Domagoj Đikić (član povjerenstva)
• Committee member: Sandra Radić Brkanac (član povjerenstva)
• Committee member: Jasna Lajtner (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2013-02-05, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

Riječni rak, Astacus astacus, i uskoškari rak, Astacus leptodactylus, su autohtone europske vrste desetoronoţnih rakova iz porodice Astacidae. U rijeci Mrežnici su rasprostranjene obje vrste, s tim da vrsta A. astacus nastanjuje gornji, uzvodni dio toka, a vrsta A. leptodactylus obitava u donjem dijelu toka te pokazuje tendenciju uzvodnog širenja. U središnjem dijelu toka Mrežnice dolazi do kontakta između ove dvije vrste. Cilj istraživanja je pronaći značajke koje najbolje odvajaju istraživane populacije i utvrditi moguće postojanje hibrida između istraživanih vrsta. Morfometrijska istraživanja su provedena na 198 ulovljenih jedinki obje vrste sa tri lokacije u rijeci Mrežnici. Multivarijantnom diskriminantnom analizom dobivenih podataka su utvrđene značajke koje najbolje odvajaju populacije. Rezultati multivarijantne diskriminantne analize morfometrijskih podataka su uspoređeni s otprije dobivenim rezultatima s drugih lokacija. Oni pokazuju da se riječni rakovi iz Mrežnice statistički značajno razlikuju od geografski bliskih populacija riječnih rakova pa je moguće da se radi o hibridima riječnih i uskoškarih rakova.

Abstract (english)

Noble crayfish, Astacus astacus, and narrow-clawed crayfish, Astacus leptodactylus, are native european species of freshwater crayfish from family Astacidae. Both species live in the Mrežnica River, A. astacus in upstream parts of the river, while A. leptodactylus occupies downstream area with tendencies of upstream spreading. Contact between these two species is observed in the middle section of the Mrežnica River. Aim of this research is to find characteristics which distinguish investigated populations with most reliability and to determine the possibility of hybrids between researched species. The analysis of morphometric characteristics was performed on 198 crayfish of both species caught in three locations in the Mrežnica River. Characteristics which distinguish populations with most reliability were found with multivariate discriminant analysis. Results of multivariate discriminant analysis of morphometric data were compared to the results obtained previously, from other locations. They show that noble crayfish from the Mrežnica River statistically differ from noble crayfish of geographically close populations, so there is a possibility that they are, in fact, hybrids between noble crayfish and narrow-clawed crayfish.

• Keywords: slatkovodni deseteronožni rakovi; morfologija; diskriminacija; hibridizacija
• Keywords (english): freshwater crayfish; morphology; discrimination; hybridization
• Language: croatian
• URN:NBN: urn:nbn:hr:217:908747
• Study programme: Title: Ecology; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra ekologije i zaštite prirode (magistar/magistra ekologije i zaštite prirode)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2017-04-28 08:37:28