SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '467acf053a3f8813fba517e0354723abdbb8139e96c9ac86157806f013ecf83b' 
  AND token = 'i8DdA0jNBJebeYHWk/QOqDwCvyeA7uQQalcORm7BGyo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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