Hilburn L R, Gunn S J, Castillo C
J Med Entomol. 1989 Jan;26(1):23-9. doi: 10.1093/jmedent/26.1.23.
A survey of Amblyomma Koch tick populations in southern Texas revealed that A. imitator Kohls was restricted to the two most southern counties, but that A. cajennense (Fabricius) ranged at least as far north as Kingsville, Tex. Females of the two species could be distinguished by the presence of chitinous tubercles on the festoons of A. cajennense and the presence of projections over both sides of the apron of the genital aperture in A. imitator. Males were distinguished by size, ornamentation, and the elongate ventral scutes of A. imitator. In addition, six enzymes, AATA, ACONA, IDH2, LDH, MPI, and PEP, were diagnostic for the two species and two others, aGPD and ACONC, had high diagnostic values. Resulting interspecific divergence was significant, I = 0.582. Genetic variability was higher in A. imitator (h = 0.092) than in A. cajennense (h = 0.057), but neither species exhibited marked interpopulation divergence (I = 0.991 in A. imitator, I = 0.994 in A. cajennense).
对得克萨斯州南部的科赫硬蜱种群进行的一项调查显示，模仿硬蜱局限于最南部的两个县，但卡延硬蜱（Fabricius）的分布范围至少向北延伸至得克萨斯州的金斯维尔。这两个物种的雌性可以通过卡延硬蜱尾突上存在几丁质瘤以及模仿硬蜱生殖孔围裙两侧存在突起加以区分。雄性则通过体型、纹饰以及模仿硬蜱细长的腹盾来区分。此外，六种酶，即天冬氨酸转氨酶（AATA）、乌头酸酶（ACONA）、异柠檬酸脱氢酶2（IDH2）、乳酸脱氢酶（LDH）、磷酸葡萄糖异构酶（MPI）和磷酸烯醇丙酮酸羧激酶（PEP），可用于鉴别这两个物种，另外两种酶，即α -甘油磷酸脱氢酶（aGPD）和乌头酸酶同工酶（ACONC），具有较高的鉴别价值。由此产生的种间差异显著，I = 0.582。模仿硬蜱的遗传变异性（h = 0.092）高于卡延硬蜱（h = 0.057），但两个物种均未表现出明显的种群间差异（模仿硬蜱的I = 0.991，卡延硬蜱的I = 0.994）。
