SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1e734651a235fc104cb3ca80568cd8627919fa159606604f25a5801e7a3e306d' 
  AND token = 'aJBIxDlswfu0pLL0fTdjdfpl7NNUnvfu8FSxoT6Co7w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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