SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f75c2c0467f9dbb3a1c976dddf1bbea271fb529379e4dc000802b9a8f472579b' 
  AND token = 'Yy0XjiYC1HdmPkJXRtf60xWDU5tc2tmCEyhjneBDYxc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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