SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3ca7d894e337933483ac62dfb0886e858bb0c1f7036d83d8356c5bb461b9b97e' 
  AND token = 'NpTSAMqWV0gg1wSqdrLgGy4cqlhUaqGR3DEp6dz+VUI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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