SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc805e9f9da10870b12fde3461617d225e2f53a84529c9893bed1c206f732b3f' 
  AND token = 'M1ZihUvZBAae+pvwkVDYYaQvanxNj58KIFeQ15qjCV0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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