SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '469fecbbf19ccb4d4e20c7f640a0bcccfd55fb24a367cde23ac6bd72a3eb7be5' 
  AND token = 'tEmIz1AnO5V/7qR4wlV1PIVwx2BZtilKPCSERU20Prs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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