SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ef7cdd1933bbab9b8e3b6ca3661562fed40123c293df31bea11b29dc114cbbf' 
  AND token = 'jI5mAw7Z9rc/L/VKIbuC2B317fiD4KpFQ2PuGykFgl8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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