SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8e165196993294d982a00f6a17290d59e4ead4dca6a190ce35e8b294b54987e4' 
  AND token = 'NxLdR//WFFBIvblIFcA/tNHfxKYdb2V/ei52DYXD52c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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