SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59de1942b08ee2ceae40269fb275178b86c2d2a0682fe928b98f5a8d22dd96e8' 
  AND token = 'zRdRrINNxjamuNH//0kweBLUn4ACSlBZrGgX30w8nQM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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