SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '145591aafb014a6a860c719196c752133a9b41924bb0c8361bb504fc3a2c8564' 
  AND token = 'fmxh6KqjG08L3KRHLOsZBCEJfILL6lUX2jAhPlSMZxU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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