SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f84285573ea204115e1af88a6a7442e2ba6a555e5ece7f64bf6045bb107bfffb' 
  AND token = 'xSlQsPzgVkCBxaTuCSnctJBf8HBhn7YTEifxRglB2Tg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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