SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5fa50e361cb99af9a1abcf013d55dda1e26fe11225a2a0765d441ac34702fd27' 
  AND token = 'zx99sM0RcoIA3dcy/CbR7dLsiZSriItE7UvJCf1hmVo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00060

JSON explain

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