SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c8d262aad7b7995cb8dc30192b472dce422e92c9b97c8f2b06f2f6fbdb58d559' 
  AND token = 'NS8mXrw8KxLCRyeIH6k/S9oAGFhLpdezLEga8sXe36U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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