SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1261fb807e131522e3890e4b7f52dbfb3535435f03abf4c1e7fb5ea4d2d2aa89' 
  AND token = 'zuuixmazPagRhQpq+4eNp85CrMFDwSjQXGtHOD6K9rs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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