SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e9946a04f043542c812e84eaba632ed3197661c7b1054024384cadf258dfcfdc' 
  AND token = 'EnjtkB6rCxV9WNnqy/xQWF2GWIA0wH9e0vzT8UphJJU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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