SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fa5d1e4ffd592230c95fa572dbad81b17483ff6e5b2f856642781e2fc2bd61d7' 
  AND token = 'fiJelqPEsPacKtZ59GPe/vI8jDLbuKSHfqbHst/QSYA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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