SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3dd5fb10e95eae3fb0d5dbb896541bddbf6548a516c9b72ea1d36c528f4de91e' 
  AND token = 'xiCeowmQQ/aAwzlkEnRc7GybKEygYCn6LKJ6ymr/2WU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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