SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '084c2a56fa03f54696b1048375a45ccd8dbff394c5c4bc0cabc9c6e8810eaea9' 
  AND token = 'edS21KE9kBnMAVULorMufffc+YgQanRG+eJCUBInCFU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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