SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5711f0ffebb4d7dd34711e1c9e70db96f056e38aa20d17ce27cadcc37f0d0b6e' 
  AND token = 'DpDRw2Z1CURRgdPb7AiZeIT3D9cRKQsDonK2Km/5E6Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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