SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7b065ed7a0deeabbb1a84b6b806c69d2476344ea4c6534a99646e386c2cdd966' 
  AND token = '6uI8gRx39aLGvLK/kZY/wkiplX7mr5oOSvqFwznJti0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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