SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9b43ea120ad7601e6568440423123fc4e120b4769ec6808a26a484f6253b8752' 
  AND token = 'a1zPwyyWxBEqldtyBdV3NWUuvEux6Zed3r1OvQrSsc4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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