Mission Valley Formation

{{Infobox rockunit

| name = Mission Valley Formation

| image =

| caption =

| type = Geologic formation

| age = Paleogene

| period = Paleogene

| prilithology =sandstone

| otherlithology =

| namedfor =Mission Valley, San Diego

| namedby =

| region = San Diego County, California

| country = United States

| coordinates =

| unitof =

| subunits =

| underlies =Pomerado Conglomerate

| overlies =Stadium Conglomerate

| thickness ={{convert|0|-|60|m|ft}}

| extent =

| area =

| map =

| map_caption =

}}

The Mission Valley Formation is a marine sandstone geologic formation in the Mission Valley region of southwestern San Diego County, California.{{cite book |last=Kennedy |first=Michael P. |date=1975 |title=Geology of the San Diego metropolitan area, California |url=https://archive.org/details/geologyofsandieg00kennrich |publisher=California Division of Mines and Geology }}[http://www.geiconsultants.com/stuff/contentmgr/files/0/3aaf5188d802ff649166ba80c318e433/download/geologic_formations_of_western_san_diego.pdf Geiconsultants.com: Geologic Formations of Western San Diego County]{{Dead link|date=April 2020 |bot=InternetArchiveBot |fix-attempted=yes }}, by Jeffrey D. Brown, R.G., C.E.G. − circa 1996.

Geology

The formation's sandstone characteristics are: soft and friable, light olive gray, fine to medium grained, and composed mostly of quartz and potassium feldspar. The Mission Valley Formation thins from the west to the east, with a maximum thickness of {{convert|0|-|60|m|ft}}.

It overlies the Stadium Conglomerate formation and underlies the Pomerado Conglomerate formation.

Fossil content

It preserves fossils dating back to the Paleogene period of the Cenozoic Era.{{cite web|title= Fossilworks: Gateway to the Paleobiology Database|author= ((Various Contributors to the Paleobiology Database))|url= https://www.fossilworks.org|access-date= 17 December 2021}} The formation's rocks can contain a molluscan fauna in the western and central exposures and a land-mammal fauna in the eastern exposures.

=Mammals=

==Eulipotyphlans==

class="wikitable" align="center"
colspan="6" align="center" \| Eulipotyphlans reported from the Mission Valley Formation
Genus	Species	Presence !Material	Notes	Images
Proterixoides \|P. davisi \| \|Several calcaneums, astragali and a navicular.{{Cite journal \|last1=PENKROT \|first1=TONYA A. \|last2=ZACK \|first2=SHAWN P. \|date=2016 \|title=Tarsals of Sespedectinae (?Lipotyphla) from the Middle Eocene of Southern California, and the Affinities of Eocene 'Erinaceomorphs' \|url=https://www.jstor.org/stable/44865966 \|journal=Journal of Vertebrate Paleontology \|volume=36 \|issue=6 \|pages=e1212059 \|doi=10.1080/02724634.2016.1212059 \|jstor=44865966 \|bibcode=2016JVPal..36E2059P \|issn=0272-4634}} \| \|

class="wikitable" align="center"

colspan="6" align="center" | Eulipotyphlans reported from the Mission Valley Formation

Genus

Species

Presence

!Material

Notes

Images

Proterixoides

|P. davisi

|

|Several calcaneums, astragali and a navicular.{{Cite journal |last1=PENKROT |first1=TONYA A. |last2=ZACK |first2=SHAWN P. |date=2016 |title=Tarsals of Sespedectinae (?Lipotyphla) from the Middle Eocene of Southern California, and the Affinities of Eocene 'Erinaceomorphs' |url=https://www.jstor.org/stable/44865966 |journal=Journal of Vertebrate Paleontology |volume=36 |issue=6 |pages=e1212059 |doi=10.1080/02724634.2016.1212059 |jstor=44865966 |bibcode=2016JVPal..36E2059P |issn=0272-4634}}

|

==Ferae==

colspan="6" align="center" \| Ferae reported from the Mission Valley Formation
class="wikitable" align="center"
Genus	Species	Presence !Material	Notes	Images
Ceruttia \|C. sandiegoensis \| "SDSNH locality 4888, State Road 125 North (Unit II, Mid Brown Siltstone)".{{Cite journal \|last=Tomiya \|first=Susumu \|date=2013-05-20 \|title=New carnivoraforms (Mammalia) from the middle Eocene of California, USA, and comments on the taxonomic status of 'Miacis' gracilis \|url=https://palaeo-electronica.org/content/2013/435-eocene-carnivoraforms \|journal=Palaeontologia Electronica \|language=English \|volume=16 \|issue=2 \|pages=1–14 \|doi=10.26879/364 \|issn=1094-8074\|doi-access=free }} \|SDSNH 92504 and SDSNH 92503. \| A carnivoraform. \|
cf. 'Miacis' \|cf. 'M.' hookwayi \|SDSNH locality 4715, State Route 125 Grossmont. \|SDSNH 84969 "right dentary fragment with p2, m1, and m2". \|A miacid. \|
Procynodictis \|P. progressus \|SDSNH locality 3870, Scripps Ranch North Site 70. \|"SDSNH 54413 (left dentary fragment with p2-m2); SDSNH 54414 (right dentary fragment with m1-2); SDSNH 54416 (left maxillary fragment with P4-M1)". \|A miacid. \|

==Primatomorphs==

class="wikitable" align="center"
colspan="6" align="center" \| Primatomorphs reported from the Mission Valley Formation
Genus	Species	Presence !Material	Notes	Images
Hemiacodon \|H. sp. \|V-72157.{{Cite journal \|last=Lillegraven \|first=Jason A. \|date=1980 \|title=Primates from Later Eocene Rocks of Southern California \|url=https://www.jstor.org/stable/1380040 \|journal=Journal of Mammalogy \|volume=61 \|issue=2 \|pages=181–204 \|doi=10.2307/1380040 \|jstor=1380040 \|issn=0022-2372}} \|Isolated fragmentary teeth. \|An omomyid, most similar to H. gracilis. \|
?Macrotarsius \|?M. sp. \|V-72150 & V-73138. \|Isolated molars. \|An omomyid also known from the Friars Formation, closely similar to M. jepseni. \|
Microsyops \|M. sp. cf. M. annectens \|V-72158. \|Isolated & fragmentary molar (UCMP 101619). \|A microsyopid. \|
Notharctus \|N. sp. \|V-72157. \|Damaged isolated molar (UCMP 113256). \|A notharctine similar to N. robustior. \|
Omomys \|O. powayensis \|V-71180, V-72157 & V-72158. \|Teeth. \|An omomyid also known from the Friars Formation. \|
Pelycodus \|P. sp. \| V-73138. \|Maxillary fragment (UCMP 113210). \| A notharctine. \|
Uintasorex \|U. montezumicus \|V-71180, V-71211, V-72157, V-72158, V-72176, V-72177, V-72179, V-73138 & V-73139. \|Isolated teeth. \|A microsyopid also known from the Friars Formation. \|
Walshina \|W. esmaraldensis \|SDSNH localities 3426 and 4020.{{Cite journal \|last1=López-Torres \|first1=Sergi \|last2=Silcox \|first2=Mary T. \|last3=Holroyd \|first3=Patricia A. \|date=2018-09-22 \|title=New omomyoids (Euprimates, Mammalia) from the late Uintan of southern California, USA, and the question of the extinction of the Paromomyidae (Plesiadapiformes, Primates) \|url=https://palaeo-electronica.org/content/2018/2309-new-primate-from-california \|journal=Palaeontologia Electronica \|language=English \|volume=21 \|issue=3 \|pages=1–28 \|doi=10.26879/756 \|issn=1094-8074\|doi-access=free }} \|Teeth. \|An omomyid also known from the Sespe & Santiago formations. \|
Washakius \|W. woodringi \|V-71211, V-72157, V-72158, V-72176, V-72179 & V-73138. \|Teeth & jaw elements. \|An omomyid also known from the Friars Formation. \|

class="wikitable" align="center"

colspan="6" align="center" | Primatomorphs reported from the Mission Valley Formation

Genus

Species

Presence

!Material

Notes

Images

Hemiacodon

|H. sp.

|V-72157.{{Cite journal |last=Lillegraven |first=Jason A. |date=1980 |title=Primates from Later Eocene Rocks of Southern California |url=https://www.jstor.org/stable/1380040 |journal=Journal of Mammalogy |volume=61 |issue=2 |pages=181–204 |doi=10.2307/1380040 |jstor=1380040 |issn=0022-2372}}

|Isolated fragmentary teeth.

|An omomyid, most similar to H. gracilis.

|

?Macrotarsius

|?M. sp.

|V-72150 & V-73138.

|Isolated molars.

|An omomyid also known from the Friars Formation, closely similar to M. jepseni.

|

Microsyops

|M. sp. cf. M. annectens

|V-72158.

|Isolated & fragmentary molar (UCMP 101619).

|A microsyopid.

|

Notharctus

|N. sp.

|V-72157.

|Damaged isolated molar (UCMP 113256).

|A notharctine similar to N. robustior.

|

Omomys

|O. powayensis

|V-71180, V-72157 & V-72158.

|Teeth.

|An omomyid also known from the Friars Formation.

|

Pelycodus

|P. sp.

| V-73138.

|Maxillary fragment (UCMP 113210).

| A notharctine.

|

Uintasorex

|U. montezumicus

|V-71180, V-71211, V-72157, V-72158, V-72176, V-72177, V-72179, V-73138 & V-73139.

|Isolated teeth.

|A microsyopid also known from the Friars Formation.

|

Walshina

|W. esmaraldensis

|SDSNH localities 3426 and 4020.{{Cite journal |last1=López-Torres |first1=Sergi |last2=Silcox |first2=Mary T. |last3=Holroyd |first3=Patricia A. |date=2018-09-22 |title=New omomyoids (Euprimates, Mammalia) from the late Uintan of southern California, USA, and the question of the extinction of the Paromomyidae (Plesiadapiformes, Primates) |url=https://palaeo-electronica.org/content/2018/2309-new-primate-from-california |journal=Palaeontologia Electronica |language=English |volume=21 |issue=3 |pages=1–28 |doi=10.26879/756 |issn=1094-8074|doi-access=free }}

|Teeth.

|An omomyid also known from the Sespe & Santiago formations.

|

Washakius

|W. woodringi

|V-71211, V-72157, V-72158, V-72176, V-72179 & V-73138.

|Teeth & jaw elements.