SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2853a2c711d091148831ccc44af0327dbff807983f6b5bb86160f168c634eb18' 
  AND token = 'nBcjHemu6KD6xvwTIYGzoRsKGr/uqpSiH/zw/xJPvw4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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