SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89fcc271d415db74c00548ed856faff911c4468cd3cabc775e292b4ac6a3e900' 
  AND token = 'MB/uWnoV/JtzB7o/QbLjizPpqdWMl7QH1WGlEf2uvSw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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