SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4a85a0eb692ea53937fcdbe8dc60f823516cf55b7325043ae798d4a52efdd0ac' 
  AND token = 'ICJlhjkh76nd8EwIBH3ROmUdvqYVmg8mixoPIv7ZhS0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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