SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '93a1f9be52122f2aa87826bd01e2dbeacf4c15f25f9024f4580ebd8c288170e5' 
  AND token = 'LMsN623wdB1o4tN/50VDdeg8P7bnTG6mwGQrkaRED/0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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