SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '82d56d321ccbd55b75e39cf18e0645f756dfe786b13f227fbd6c03faa3cb5a00' 
  AND token = 'nJIxfp4CP2a4FcZOfIe3EOuWG5D8XxA3txqVATc9WF4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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