SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ea7f4592592eac622b05f153afc92044928f4da4a80cb380a6a26b48f478e445' 
  AND token = 'zGwBfHg83SrsZ1mMn8uT+hjshbjJtHWmIVinT1UWOso=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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