SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a57a9b9654d4d3a27ad7c294aade6c882587ddc98a07e99acffa69d0d39718b7' 
  AND token = 'bruWQEBzutDp9KvzW/gtRHYGBr0mc3+5jeCRlraNR8w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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