Friday, September 18, 2015

Spiders Cannot Be Identified By Color And Pattern Alone


Atypical Araneus diadematus
female photographed in
Seattle, Washington, USA
Typical appearance of
Araneus diadematus female.
Photo by Friedrich Böhringer
My neighborhood is absolutely festooned with the introduced orb-weaver Araneus diadematus (Araneidae).  By late summer, hardly a shrub or a structure is devoid of one of these orange and brown spiders with the striking white pattern on the dorsum (left).  So I got excited when I spotted a large orange orb-weaver (right) on my balcony that lacked the color and patterning of A. diadematus.  Could a native species of orb-weaver actually be thriving in Seattle, at my house?!

Answer: No, not in this case.

Genitalia of an atypically colored and patterned
Araneus diadematus female from
Seattle, Washington USA.
The spider in question is fairly large (over 0.5 inch long) with distinctive external genitalia, so I was able to identify her with reasonable certainty from a photo (right) as an A. diadematus. (Most species are much too small and/or have genitalia too complex to be identified via photos.)  Despite this spider's exotic appearance, she was just "more of same", albeit atypically colored and patterned.

So, as nice as it would be to identify spiders in the field from easily observable traits like color and pattern, such features aren't necessarily diagnostic and in fact can be misleading.  The only way to identify spiders with certainty is by examining the shape of their genitalia and other tiny, immutable features under a microscope.

Saturday, September 12, 2015

In Search Of Leslie Maurice Cockerell (1872-1943), Collector of Euryopis formosa (Theridiidae) Holotype

Nathan Banks (1908) cited L. M. Cockerell as the
collector of the E. formosa holotype
"By himself, a collector has no sort of scientific value, but he often secures material which may be turned to good account in other hands." ~~ T. D. A. Cockerell

When I was assembling the data presented in How widespread is Euryopis formosa's relationship with pines?, I noticed that Nathan Banks (1908) named L. M. Cockerell as the collector of the E. formosa holotype.  I became curious about the person who collected the first described specimen of a species that has enthralled me for several years.  Who was L. M. Cockerell?  How did this person come to be collecting spiders in Bear, Idaho over 115 years ago, and how did the specimen come to be in the hands of Banks, a prominent entomologist?

My research* revealed that L. M. Cockerell was Leslie Maurice Cockerell, born in Beckenham, County Kent, England in 1872 to Sydney John and Alice Elizabeth (née Bennett) Cockerell.  His siblings included the naturalist and bee expert Theodore Dru Alison "T.D.A." Cockerell (1866–1948), director of the Fitzwilliam Museum Sydney Carlyle Cockerell (1867-1962), book illustrator Olive Juliet Cockerell (1869-1910), book binder Douglas Bennett Cockerell (1870-1945), and actress Una Agnes Cockerell (about 1875-about 1944).

After spending his late teens and early adulthood years in Madeira, eastern Canada and the western United States, Leslie would eventually become a "mining engineer who is representing large English mining interests" in Mexico and then later serve as captain in the British Army "in charge of Mineral Resources Development Department, Ministry of Munitions".  Leslie married Gladys Marguerite [unknown maiden name] (1880-1969) at some date unknown to me, but presumably before the couple set sail together from an American port in 1907.  He died in London, England on 24 April 1943.

Location of Bear, Idaho (click to enlarge)
Unfortunately, the date that Leslie collected the E. formosa holotype in Bear, Idaho went unrecorded by Banks (1908) or by Harvard University's Museum of Comparative Zoology, which currently houses it.  I suspect that Leslie collected the specimen sometime between 1890 and 1894, for the following reasons.

First, letters written between 1887 and 1890 by Leslie's brother T.D.A. Cockerell during his convalescence from tuberculosis in Colorado indicate that Leslie was in Madeira 1887-1888 and eastern Canada 1888-1890, but never traveled to the western United States while T.D.A. was there (Weber, 2004).  In June of 1890, shortly before T.D.A. returned to England, T.D.A. wrote that "Mother's postcard (received today) makes me rather anxious.  It seems Leslie will probably have to come to Colorado.  I must see about this on my return." (p. 550).  Thus, the earliest that Leslie could have been in the western United States was the latter half of 1890.  Second, Leslie was in Colorado by 1892 according to the "May 1891 to April 1892" issue of the journal Nautilus, which published a note from "Leslie M. Cockerell, writing from Norwood, San Miguel Co., Colorado" (p. 83).  Third, in 1894 Nathan Banks described a harvestman that Leslie had also collected in Bear, Idaho.  Assuming that he collected the harvestman and the E. formosa on the same visit to Bear, the 1894 publication provides the closing bracket. Record of Leslie sailing on the ship Anchoria from New York City to Glasgow, Scotland in June, 1895 seems to confirm the end of that particular trip to the United States.

Update (Oct 30, 2015): Leslie Cockerell returned again to Idaho by the latter half of 1898, according to two sources.  A notice in the Sunday, July 31, 1898 issue of Idaho Statesman (Boise) stated: "HOTEL ARRIVALS. Capitol. ... Leslie M. Cockerell, Payette".  Additionally, the University of Colorado Boulder Library archives holds a letter dated December 7, 1898 that Leslie sent from Payette, Idaho to his brother T.D.A. Cockerell.  Payette is located about 50 miles south of Bear.  Thus it is possible that Leslie again visited Bear on this subsequent trip to the American West.

As for why Leslie traveled to the American west, what he experienced there, what impressions it left on him, or even why he collected spiders and how his arachnid specimens ended up in Nathan Banks's collection, those questions remain unanswered.  If Leslie Cockerell left a diary or memoir, I have found no mention of it.  Perhaps letters by Leslie or about him await reading in the archived papers of Nathan Banks (Cambridge, Massachusetts), T.D.A. Cockerell (Boulder, Colorado) or Sydney Carlyle Cockerell (Boston, Massachusetts; London, England; etc.).  Alas, I'm unlikely to visit any of those places anytime soon.  I hope others who are more conveniently located will bring any remaining information to light.  T.D.A. took great delight in young Leslie's "first rate" letters to him (Weber, 2004), so if any survive in archives, they're probably a good read.

As T.D.A.'s quote at the top of the post recognizes, people like Leslie who aren't career scientists but rather "just" science hobbyists, volunteers or assistants play important roles in the advancement of science.  Scientific institutions everywhere are enhanced by their contributions, but they themselves are not memorialized in academic archives or biographies.  Their stories are lost to the history of science.  We should make an effort to remedy that.

Literature Cited

Banks, Nathan. 1894. Washington Phalangida, with description of a new southern Liobunum. The Canadian Entomologist, 26(6):160-164.

Banks, Nathan. 1908. New species of Theridiidae. The Canadian Entomologist 40:205-208.

Weber, William A. (Ed.) 2004.  The Valley of the Second Sons: Letters of Theodore Dru Alison Cockerell, a Young English Naturalist, Writing to His Sweetheart and Her Brother about his life in West Cliff, Wet Mountain Valley, Colorado 1887-1890. Pilgrims Process, Inc., Santa Fe, New Mexico. 592 pages.

*To piece together this story I conducted online Google and Ancestry.com searches, read Trevor Kincaid's correspondence with Nathan Banks and T.D.A. Cockerell, and read The Valley of the Second Sons (Weber, 2004).