SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3bc9abb4310c825f89c1a694ecdf9bac9fdea618d250cf86db74f59558087928' 
  AND token = 'ic9A1JhRsU8aCSLLjXdDKnlxeFwR6dPEkPT/WVLkJf0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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