SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ffd4573c22ba014e21a1e3656312e4ce9d3548bb788db99a4c0bc174553106bf' 
  AND token = '2BWh7H+uqD0TCZG8ra89eXjBLYXFSzG2anrCAOK5a+E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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