SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6eac18686709b90eac14ed3e8ad02c7aaf26ae99c2121404c226fc95b7684055' 
  AND token = 'cQpRoHFW/peiqnDXSXPCaJr3Y33e4ub2NKnawM+Q/6U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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