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==Udseende==
Timeglasdelfinen er umiskendelig i sit udbredelsesområde med den kraftige [[rygfinne]] og de skarpt markerede sorte og hvide tegninger, der fra siden ligner et liggende [[timeglas]] og fra rygsiden minder om et [[malteserkors]] (heraf navnet korshvidskæving og det latinske [[artsnavn]] ''cruciger''. Kun den [[sydlig rehvalsdelfin|sydlige rethvalsdelfin]] kan forveksles med timeglasdelfinen, men da rethvalsdelfinen mangler en [[rygfinne]] er de to arter nemme at adskille.
The hourglass dolphin is colored black and white and for this reason was colloquially known by whalers as a "sea [[cow]]". Each flank has a white patch at the front, above the beak, eye and flipper, and a second patch at the rear. These two patches are connected by a thin white strip, creating, loosely speaking, an [[hourglass shape]] and hence the common name of the dolphin. The scientific name ''cruciger'' is [[Latin]] for "cross-carrier". This refers to the area of black coloration, which, viewed from above, vaguely resembles a [[Maltese cross]] or [[cross pattée]].
Fuldt udvoksede individer er omkring 1.8 m lange og vejer 90-120 kg. På grund af det lave antal timeglasdelfiner man har undersøgt er det vanskeligt at afgøre om der er kønsforskelle i størrelse, men det formodes at hannerne er lidt mindre og lettere end hunnerne.
In its usual range the dolphin is easily identifiable. Only the [[southern right whale dolphin]] is of comparable size and lives as far south. The right whale dolphin does not have a [[dorsal fin]], so the two species are easily distinguished. The fin considerably varies across individuals. It is generally tall and curved, and the curve may be particularly pronounced in older animals.
A fully grown adult is about {{m to ft|1.8}} length and weighs {{convert|90|-|120|kg}}. Males are thought to be slightly smaller and lighter than females, although the small number of specimens does not permit a firm conclusion.
==Bestand og udbredelse==
TheUdbredelsen range iser [[circumpolar]] fromfra closeden to[[antarktis|| theantarktiske]] Antarctic[[pakis]] icetil pack to aboutomkring 45°S., hvor arten Thetræffes på det åbne hav. mostDe northerlynordligste confirmedsikre sightingsobservationer wereer 36°S in the Southi [[Atlantic OceanSydatlanten]] andog 33°S neari østlige [[ValparaísoStillehav]], nær [[ChileValparaíso]], in the [[PacificChile]]. SightingsTimeglasdelfiner haveses beenhyppigst madesyd most commonly from the south offor [[New Zealand]], around theomkring [[South Shetland Islandsøerne]] andog offi [[TierraDrake del FuegoStrædet]], [[Argentina]]. The species is unlikely to be particularly densely populated close to these lands.
One survey estimated the population size at more than 140,000 individuals.{{Citation needed|date=October 2010}}
==Adfærd==
Timeglasdelfiner træffes oftest i små grupper på 5-10 individer. Største rapporterede gruppe var på 60 dyr.
Hourglass dolphins tend to move in groups of about 5 to 10. One [[International Whaling Commission]] study recorded a group of 60.
Timeglasdelfiner ses ofte søge føde sammen med andre hvaler, især [[finhvale]]er, men også [[sejhval]], [[vågehval]], [[sydlig døgling]], [[langfinnet grind]] og [[sydlig rethvalsdelfin]]. Timeglasdelfiner kommer gerne til skibe for at ride på [[bovbølge]]n.
They share feeding grounds with other cetaceans such as [[sei whale|sei]], [[pilot whale|pilot]], [[bottlenose whale|bottlenose]] and [[minke whale]]s and [[southern right whale dolphin]]s. They are regularly seen with [[fin whale]]s. Whalers who were hunting these much larger animals used hourglass dolphins as "look-outs" to aid them in their hunt. Hourglass dolphins are keen bow-wave riders.
De sparsomme undersøgelser af maveindhold angiver at timeglasdelfiner lever af forskellige [[blæksprutter]] og småfisk.
Examinations of the stomach contents of the few specimens indicate they eat various (unrecorded) types of [[squid]] and small fish.
==Referencer==
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