SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e9b1efb67383cfbfac18a84f17425d791c720887d416a28365b9c8aa93622385' 
  AND token = '4G6SW/j7ZwoFhaRgQYEO8M08Ynbimwe4MFBxAqOpAsA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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