SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '5a67901034d745118e00a83009fc4c57273e03b6854140b071f6e1f9f1b6f47e' 
  AND token = 'k5Ss9HV8JzFcLMsMpX5bfRWYDPqTBEzZAtCzItu/a+4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}