Galeus

Galeus Temporal range: Early Miocene–Present[1] PreꞒ Ꞓ O S D C P T J K Pg N
Blackmouth catshark (Galeus melastomus)
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Chondrichthyes
Subclass:	Elasmobranchii
Subdivision:	Selachimorpha
Order:	Carcharhiniformes
Family:	Scyliorhinidae
Genus:	Galeus Cuvier, 1816
Type species
Galeus melastomus Rafinesque 1810[2]
Synonyms
Pristiurus (subgenus of Scyllium) Bonaparte, 1834

Galeus is a

Galeus, derived from the

• Galeus antillensis S. Springer, 1979 (Antilles catshark)
• Galeus arae Nichols, 1927 (roughtail catshark)
• Vaillant
  , 1888 (Atlantic sawtail catshark)
• Galeus cadenati S. Springer, 1966 (longfin sawtail catshark)
• Galeus eastmani D. S. Jordan & Snyder, 1904 (gecko catshark)
• Galeus friedrichi Ebert & Jang, 2022 (Philippines sawtail catshark)
• Compagno & Stevens
  , 1993 (slender sawtail catshark)
• Galeus longirostris Tachikawa & Taniuchi, 1987 (longnose sawtail catshark)
• Galeus melastomus Rafinesque, 1810 (blackmouth catshark)
• Galeus mincaronei Soto, 2001 (southern sawtail catshark)
• Galeus murinus Collett, 1904 (mouse catshark)
• Galeus nipponensis Nakaya, 1975 (broadfin sawtail catshark)
• Galeus piperatus S. Springer & M. H. Wagner, 1966 (peppered catshark)
• Galeus polli Cadenat, 1959 (African sawtail catshark)
• Galeus priapus Séret & Last, 2008 (phallic catshark)
• Galeus sauteri D. S. Jordan & R. E. Richardson, 1909 (blacktip sawtail catshark)
• Galeus schultzi S. Springer, 1979 (dwarf sawtail catshark)
• Galeus springeri Konstantinou & Cozzi, 1998 (Springer's sawtail catshark)

Phylogeny and evolution

Most taxonomic studies have concluded the closest relatives of Galeus to be

Ma) and Langhian (15.97–13.65 Ma) stages of the early Miocene, have been recovered from France.^[1]

Distribution and habitat

The centers of

slopes.^[10][12]

Description

Sawtail catsharks reach maximum lengths of between 25 and 90 cm (9.8 and 35.4 in). They have slender, firm bodies and narrow, slightly flattened heads with short to long, pointed snouts. The nostrils are divided into incurrent and excurrent openings by triangular flaps of skin on their anterior rims. The horizontally oval eyes are placed mostly on the sides of the head and equipped with rudimentary nictitating membranes (protective third eyelids); below each eye is a subtle ridge, and behind is a small spiracle (auxiliary respiratory opening). The mouth is rather large and wide, and when closed the upper teeth are exposed. There are short to long furrows around the corners of the jaws. The teeth are small and number 47–78 rows in the upper jaw and 48–82 rows in the lower jaw; each tooth has a narrow central cusp flanked by one or more smaller cusplets on either side. There are five pairs of gill slits.^[3][12]

The two

caudal peduncle can be nearly cylindrical to laterally compressed, depending on species. The caudal fin comprises more or less a quarter of the total length, and is low with a small lower lobe and a ventral notch near the tip of the upper lobe.^[3][12][13]

The skin is thick and densely covered by small, overlapping, well-

G. springeri also have a similar crest along the ventral margin of the caudal fin. Galeus species are typically grayish or brownish above and lighter below, and most have a pattern of darker saddles and/or blotches along the back and tail. The interior of the mouth may be light or dark.^[3][12][14]

Biology and ecology

Natural history data is scant for most Galeus species. They feed on various types of

derived.^[16]

Human interactions

Sawtail catsharks pose no danger to humans and have little economic value, though varying numbers are

Near Threatened and Vulnerable respectively.^[17][18]

References

1. ^ ^{a b} Marsili, S. (2007). "A new bathyal shark fauna from the Pleistocene sediments of Fiumefreddo (Sicily, Italy)" (PDF). Geodiversitas. 29 (2): 229–247. Archived from the original (PDF) on 2011-06-12.
2. ^ Rafinesque, C.S. (1810). Caratteri di alcuni nuovi generi e nuove specie di animali e piante della Sicilia, con varie osservazioni sopra i medisimi. (Part 1 involves fishes, pp. [i-iv] 3-69, Part 2 with slightly different title, pp. ia-iva + 71-105). Pls. 1-20.
3. ^
   ISBN 1-930665-76-8
   .
4. ^ "Characters of various new genera and species of animals (mostly fishes) and plants, with various observations about them"
5. ^ Fowler, H.W. (1908). "Notes on sharks". Proceedings of the Academy of Natural Sciences of Philadelphia. 60: 52–70.
6. ^ Bigelow, H.W.; W.C. Schroeder. "Sharks". Memoirs of the Sears Foundation of Marine Research. 1: 53–576.
7. doi:10.1080/00222935208654389
   .
8. ^
   PMID 15683930
   .
9. ^
   PMID 16293425
   .
10. ^
    ISBN 978-0-691-12072-0
    .
11. doi:10.11646/zootaxa.1813.1.2
    .
12. ^
    ISBN 92-5-101384-5
    .
13. ^ Nakaya, K. (1975). "Taxonomy, comparative anatomy and phylogeny of Japanese catsharks, Scyliorhinidae". Memoirs of the Faculty of Fisheries, Hokkaido University. 23: 1–94.
14. JSTOR 1447711
    .
15. doi:10.1046/j.1444-2906.2000.00133.x
    .
16. ^ Iglésias, S.P.; M.H. du Buit & K. Nakaya (2002). "Egg capsules of deep-sea catsharks from eastern North Atlantic, with first descriptions of the capsule of Galeus murinus and Apristurus aphyodes (Chondrichthyes: Scyliorhinidae)". Cybium. 26 (1): 59–63.
17. doi:10.2305/IUCN.UK.2007.RLTS.T63149A12623555.en
    . Retrieved 14 January 2018.
18. doi:10.2305/IUCN.UK.2004.RLTS.T44578A10921845.en
    . Retrieved 14 January 2018.

• Froese, Rainer and Pauly, Daniel, eds. (2011). Species of Galeus in FishBase. February 2011 version.