SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '465a48084b4832e08566ef7540ca8ab4cc39bae99900ccf85f3a18f1423d9f4f' 
  AND token = 'SbaXWXPKDfGcMLoUn486Qjs81fP7VHdeiTbNmMQNyoA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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