SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bc7c23026cb7a8be2cfc064b90900182e0c391614163ed359745d9962b17fcb2' 
  AND token = 'GS+YCYqyzukf5eDEUpZqIhiSedZav6Ow482l0OOU57U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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