SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '52e46fe74e9b7e88290035850f83b0e15aeb6c7b7f3daf576ddd055fec8d5245' 
  AND token = 'whCNnNfqXgj89hrmFJNGr/yz5WKIIuRxbobB6b87HJU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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