SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '99b9505d55799485a7959031c2368bdb823c69fd7edff4787434ff71d70fa3bc' 
  AND token = 'QvtZWpQZunnBBuGSdO4HaC7Mv1qmTf5hmnAJTTC14tM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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