SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '91dc99a7ec30b2df97af56aa0da28e9181b2ad8517f7adeed664e38e5dd80ac5' 
  AND token = 'wIlfHZGDAPHGSCxY7xJpudbyCJFetEGShErtxmv8Omk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00065

JSON explain

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