SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fafcab6ea904ec155e71812c68efc608fbef6e7c3795f9eb12802f647b1bebcd' 
  AND token = 'tpKFYkMXiDVtmfqoFFMpiYSRBe2AFRuohG6CilamYME=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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