Leptarma jamelense ( Rathbun, 1914 )

Lagare, Nickel Jean S., Mapi-Ot, Emmarie F., Molina, Ziljih S., Neri, Jemateo B., Nuñeza, Olga M. & Mendoza, Jose Christopher E., 2020, On a collection of freshwater and estuarine crabs (Crustacea: Brachyura) from Mindanao Island, the Philippines, Zootaxa 4868 (3), pp. 301-330 : 307-308

Leptarma jamelense ( Rathbun, 1914)

Figs. 3E , 6 E–H

Sesarma (Parasesarma) moluccensis jamelensis Rathbun 1914: 81 .

Sesarma (Parasesarma) molucense jamelense, Estampador 1937: 536 ; 1959: 93.

Sesarma (Parasesarma) jamelensis, Tesch 1917: 178 ; Serène 1968: 108.

Parasesarma jamelense, Ng et al. 2008: 222 ; Rahayu & Li 2013: 633 , figs. 1–3.— Shahdadi & Schubart 2017: 536 (list).

Material examined. 1 male, 10.6 by 9.7 mm, ( ZRC; NJL161013 ) Tagoloan River, Brgy. Poblacion, Tagoloan town , Misamis Oriental prov., coll. N. J Lagare, 24-25 Sep. 2016 .

Remarks. This species was described as Sesarma (Parasesarma) moluccensis jamelensis by Rathbun (1914) based on a few specimens collected from Point Jamelo (= Hamilo Point), Batangas Province, Luzon Island. Estampador (1937, 1959) subsequently reported this species from Taytay, Palawan Island, further to the southwest. The types remained un-illustrated until Rahayu & Li (2013) provided photographs and line drawings of the male holotype deposited in the Natural Museum of Natural History, Washington, D.C. (USNM). The last author (JCEM) has also examined the types at the USNM (catalog no. USNM 45917). The present male specimen from Tagoloan River resembles the holotype in the general shape of the carapace, pleon, and the leg proportions, as well as in having 10 tubercles on the dorsal surface of the chelar dactylus. It differs from the holotype, however, in having 9 and 15 teeth on the proximal and distal pectinated crests, respectively, (versus 10–11 and 16–18, respectively, in the holotype viz. Rahayu & Li (2013)), and in having a relatively longer chitinous distal tip on the G1 ( Figs. 6G, H ). Shahdadi et al. (2020) recently revised the genus Parasesarma , wherein their molecular analyses revealed a distinct clade, which they called the Parasesarma leptosoma species-group (17 species including P. jamelense ). They established a new genus, Leptarma (type species: Sesarma leptosoma Hilgendorf ), for this group using both molecular and morphological characters (e.g., tuberculation pattern on the chelar dactyli). For the moment, we consider the Tagoloan specimen as conspecific with Leptarma jamelense , but recommend a comprehensive examination of all the Philippine material and comparisons with material of morphologically similar species such as P. liho Koller, Liu & Schubart, 2010 , originally described from Taiwan (see also Shahdadi et al. 2020, discussion on Leptarma ). The latter species has specimens recorded from Cebu Island in the Philippines ( Shih et al. 2019), which is about 200 km north of Tagoloan, across the Bohol Sea, as well.

New Mindanao record.

Figures

FIGURE 3. Colour photos of recently preserved crabs (dorsal habitus). A, Neosarmatium asiaticum Ragionieri, Fratini & Schubart, 2012, male, 37.0 by 30.0 mm (ZRC), Sindangan, Zamboanga del Norte; B, Neosarmatium fourmanoiri Serène, 1973, male, 40.6 by 33.8mm (ZRC), Sindangan, Zamboanga del Norte; C, Neosarmatium indicum (A. Milne-Edwards, 1868), male, 14.4 by 12.1 mm (ZRC), Basilisa, Dinagat Island; D, Parasesarma anambas Yeo, Rahayu & Ng, 2004, male, 8.6 by 7.0 mm (ZRC), Lianga, Surigao del Sur; E, Leptarma jamelense (Rathbun, 1914), male, 10.6 by 9.3 mm (ZRC), Tagoloan, Misamis Oriental; F, Parasesarma kuekenthali (De Man, 1902), male, 15.4 by 13.0 mm (ZRC), Basilisa, Dinagat I. Scale bars: 10 mm.

FIGURE 6. A–D, Parasesarma anambas Yeo, Rahayu & Ng, 2004, male, 8.6 by 7.0 mm (ZRC), Lianga, Surigao del Sur; E–H, Leptarma jamelense (Rathbun, 1914), male, 10.6 by 9.3 mm (ZRC), Tagoloan, Misamis Oriental.A, E, left chela, external view; B, F, left chela, dorsal view; C, G, right G1, pleonal view; D, H, right G1, sternal view. Scales: A, B, E, F = 2.0 mm; C, D, G, H = 1.0 mm.