Hesperoboreus notoperates  (Cooper, 1972)


Diagnosis:  The species of Hesperoboreus have a relatively short maxilla-labial complex of the rostrum; lack of spines on the male forewing (except apical spine); male ninth tergum lacking medial hood; male ninth sternite deeply notched; forewing of female without apical bristles; female ovipositor short, ninth sternite less than twice height of eighth segment. 


Distribution – Geographical:  This species is only known from Coldwater and Black Canyons, near Mountain Center, at 1219 m elevation on Mount San Jacinto in southern California.


Distribution – Temporal: Adult emergence is from mid-November until mid-March.


Ecology:  Larvae and pupae live in the mosses on dioritic boulders of northwest faces of steep canyons.  During the drier parts of the year, larvae form small cells around themselves, cemented with salivary secretions, but not silk.  Temperatures on these rocks can reach 30°C, and mosses become dry and brittle during dry seasons.  The mean precipitation in this area is 59.6 cm (23 inches) per year, with most of that rainfall coming between November and March.  Larvae feed on the mosses: Grimmia apocarpa Hedw., Grimmia montana B.S.G., Rhacomitrium sudeticum (Funck.) B.S.G., and Orthotrichum rupestre Schleich. ex. Schwaeger.


Biology:  Males and females mate repeatedly with various partners.  Eggs are laid individually in a vertical orientation near the surface of the moss rhizoids and females lay a minimum of 1.16 eggs per day with a total fecundity of at least 32 eggs per female.  Hatching occurs in 8 to 10 days after temperatures begin to warm up, usually in early spring.  Moulting to 2nd instar larvae takes place in about 16 to 17 days.  Development appears to take two years.  Metamorphosis to the pupal stage usually takes place from mid-August to September (Cooper, 1974).


Notes:  H. notoperates can be separated from the only other known species of Hesperoboreus by the notched ninth sternite of males and the lack of apical forewing bristles of females.


This species has a diploid number of 20 in the female and 19 in the XO male (Cooper, 1974).


This is the furthest south that any boreid has been recorded and the special cell constructed for the dry season is probably an adaptation for this extreme climate.


The name is derived from the Greek notos = south and perates = wanderer and refers to the extremely southern distribution of this species.




Cooper, K.W. 1972. A Southern California Boreus, Boreus notoperates n.sp. I. Comparative Morphology and Systematics. (Mecoptera: Boreidae). Psyche, 79:269-283.


-----. 1974. Sexual Biology, Chromosomes, Development, Life Histories and Parasites of Boreus, especially of B. notoperates. A Southern California Boreus. II. (Mecoptera: Boreidae). Psyche, 81:84-120.






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