Ελασμοβράγχιοι (καρχαρίες και σαλάχια) (sharks and rays) >
Pristiophoriformes (Saw sharks) >
Pristiophoridae (Saw sharks)
Etymology: Pliotrema: pleion (Gr.), more; trema (Gr.), hole, referring to six gill slits compared with five in Pristiophorus (See ETYFish); annae: In honor of Anna Weigmann Huerta, the senior author’s niece, “to express its relationship” to P. kajae, named after the senior author’s daughter (See ETYFish).
Eponymy: Anna Weigmann Huerta (d: 2017) is the niece of the first author. The species was named in her honour “…to express its relationship to Pliotrema kajae, named after the first author’s daughter Kaja Magdalena Weigmann.” (Ref. 128868), visit book page.
Περιβάλλον: περιβάλλον / κλιματική ζώνη / εύρος βάθους / εύρος διανομής
Οικολογία
Θαλασσινό(ά) βενθικό(ς); εύρος βάθους 20 - 35 m (Ref. 122027). Tropical
Western Indian Ocean: Zanzibar and probably off Kenya and Somalia.
Μέγεθος / Βάρος / Ηλικία
Γεννητική Ωρίμανση: Lm ? range ? - ? cm
Max length : 98.0 cm TL (female)
Σύντομη περιγραφή
Κλείδες προσδιορισμού | Μορφολογία | Μορφομετρία
This medium-sized six-gilled sawshark is distinguished by the following characters: barbel origin to anterior nostrils 1.9-2.0 times anterior nostrils to symphysis upper jaw; prenarial length 1.6-1.7 times prebarbel length; preoral length 1.5-1.7 times interdorsal space; pectoral-fin anterior margin 1.4-1.5 times dorsal-caudal space; mouth width 2.7-3.2 times spiracle length; the first dorsal fin originates about opposite pectoral-fin free rear tips; lateral trunk dermal denticles tricuspidate, rather flat and imbricated; monospondylous centra 53-54; precaudal diplospondylous centra 46-49; total vertebral centra 154; generally with a shorter snout, head length 34.2-34.5% TL, preorbital length 21.7-22.0% TL, preoral length 24.6-25.1% TL, prebarbel length 12.6-12.7% TL, and barbel origin to symphysis upper jaw 12.1-12.3% TL; with lower total large lateral rostral tooth and ventral rostral spine counts, and a rostrum that is slightly constricted between barbel origin and nostrils. Similar to P. kajae, with barbels situated about half way from rostral tip to mouth, with prebarbel length about equidistant from barbel origin to symphysis of upper jaw, while in P. warreni, the barbels are situated about two thirds way from rostral tip to mouth, with prebarbel length about twice distance from barbel origin to symphysis of upper jaw. Colouration: uniform medium to dark brown dorsally without longitudinal stripes; white ventrally but with few indistinct dark blotches on belly; fins with pronounced white posterior fin margins, especially the caudal and pectoral fins; dorsal rostrum surface with two distinct longitudinal dark stripes, lateral rostral teeth dark-edged (Ref. 122027).
Cross section: angular.
Probably occurs in deeper waters during the day but enters shallow water during the night. The specimens were caught directly adjacent to a dropoff along the southern tip of Unguja Island where the water depth descends rapidly from ca.20 m to >200 m (Ref. 122027).
Κύκλος ζωής και συμπεριφορά ζευγαρώματος
Γεννητική Ωρίμανση | Αναπαραγωγή | Γεννοβολία | Αβγά | Γονιμότητα | Προνύμφες
Weigmann, S., O. Gon, R.H. Leeney, E. Barrowclift, P. Berggren, N. Jiddawi and A.J. Temple, 2020. Revision of the sixgill sawsharks, genus Pliotrema (Chondrichthyes, Pristiophoriformes), with descriptions of two new species and a redescription of P. warreni Regan. PLoS ONE, 15 (3)[0228791]:1-56. (Ref. 122027)
Κατάσταση Κόκκινου Καταλόγου IUCN (Ref. 130435: Version 2025-2 (Global))
Απειλή για τον άνθρωπο
Harmless
Ανθρώπινες χρήσεις
Εργαλεία
Ειδικές εκθέσεις
Λήψη XML
Διαδικτυακές πηγές
Εκτιμήσεις βάσει μοντέλων
Δείκτης φυλογενετικής ποικιλότητας (Αναφ.
82804): PD
50 = 0.6270 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00389 (0.00180 - 0.00842), b=3.12 (2.94 - 3.30), in cm total length, based on all LWR estimates for this body shape (Ref.
93245).
Τροφικό Επίπεδο (Αναφ.
69278): 4.0 ±0.6 se; based on size and trophs of closest relatives
Ευπάθεια στην αλιεία (Ref.
59153): High vulnerability (59 of 100).
🛈
![Image of Pliotrema annae (Anna\](/images/thumbnails/jpg/tn_Plann_f0.jpg "Image of Pliotrema annae (Anna\")
