Maritisma, Smith & Mitchell, 2019

Smith, Graeme B. & Mitchell, Andrew, 2019, Species of Heterolepismatinae (Zygentoma: Lepismatidae) Found on some Remote Eastern Australian Islands, Records of the Australian Museum 71 (4), pp. 139-181 : 170-171

Maritisma gen. nov.

http://zoobank.org/NomenclaturalActs/ 56115144-6890-4115-88A2-9716C9C5EF95

Type species. Maritisma coralinium sp. nov.

Diagnosis. Medium-sized silverfish. Body shape as in Fig. 169 . Pigment apparently absent or very limited e.g., around eyes. Macrochaetae smooth with apical bifurcations. Scales multiradiate, rounded with ribs not very close together; lanceolate or triangular scales apparently absent.Antennae possibly with rod-like basiconic sensilla. Chaetotaxy of frons consisting of a row of macrochaetae along anterior margin joining laterally with rows along the sides of the head which run back along the margin and up over the eyes, peri-antennal groups weak. Clypeus with longer macrochaetae laterally and across the face proximally, with small setae medially. Labrum with many macrochaetae distributed across the proximal half and some smaller setae in the anterior half. Eyes of about 12 ommatidia. Apical article of labial palp broad with 3+2 papillae of the aufgelöst type (individual subunits of each papilla not packed closely together), those more distal very long.

Pronotum with narrow setal collar which is largely interrupted medially. Thoracic nota with marginal setae and a few submarginal combs each of just a single or two macrochaetae; each lateral margin with two open trichobothrial areas, each anterior trichobothrial area of the pronotum with a macrochaeta laterad of the trichobothrium; posterior margin with 1+1 combs each of a single macrochaeta.

Thoracic sternites free, sub-parabolic with submarginal macrochaetae along the more distal lateral regions. Legs typical for the Heterolepismatinae ; tarsi with four articles, pretarsi with two claws and a medial empodial claw. Urotergites I–VII with 3+3 small combs, urotergite VIII with 2+2 combs, urotergite IX with 1+1 sublateral setulae. Urotergite X very short, rounded with a few macrochaetae along each lateral margin. Urosternite I with medial comb, urosternites II–VIII with 1+1 long combs, each macrochaeta of all combs distinctly spaced apart from adjacent macrochaetae. Coxites IX of both sexes typical for the Heterolepismatinae , with large, prominent parameres. One pair of styli only (IX). Ovipositor of female simple.

Etymology. The genus name derives from the Latin word “maritimus” referring the proximity of known collection sites to the ocean combined with the suffix -isma, used for many silverfish. It is treated as grammatically neuter.

Remarks. When initially examined by the first author, the specimen did not immediately appear to belong to the Heterolepismatinae , however with due consideration, most characters were generally in agreement with those associated with the Heterolepismatinae . Molecular data could not be obtained for this species due to the length of time the specimens had been in 70% ethanol. The character analysis places M. coralinium sp. nov. closest to the H. stilivarians group predominantly because both share the presence of macrochaetae rather than setae on the labrum, however the species share little else in common. The stilivarians group is currently under revision and the available molecular data places it quite distant from the remaining Australian species of Heterolepisma for which molecular data is available.

The new genus can easily be distinguished from all described Heterolepismatinae (except H. dispar – see below) by the following combination of characters: the presence of chaetotaxy on the anterior margin of the frons, the absence of branched papillae on the ultimate article of the maxillary palp, the presence of 3+3 combs on urotergite I, the presence of a medial comb on urosternite I, the very long 1+1 combs of eight or more spaced macrochaetae on urosternites II–VI, the number of pairs of styli (one pair in both sexes), the wide ultimate article of the labial palp and the much shorter urotergite X.

Figures

Figures 169–180. Maritisma coralinium gen. nov., sp. nov. holotype ♂ K.261124 K.261125 (169) habitus (terminal filaments lost); (170) smooth, apically bifurcate seta of setal collar; (171) scale from pronotum; (172) head, frons drawn separate from rest as it was folded back under the clypeus in the mounted material; (173) antenna, scape, pedicel and basal intervals of flagellum; (174) idem, most distal surviving interval showing possible basiconic sensillum (bsB?); (175) mandible; (176) idem, incisor and molar regions; (177) maxilla; (178) idem, lacinia and galea; (179) idem, apex of ultimate article of palp showing basiconic sensillum type C (bs); (180) labium. Scale bars = 0.1 mm unless otherwise indicated.