SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '650d724970eefc8d975e6d3e4895940616c74f3e5a139fe20a2db8df128bfeee' 
  AND token = 'NLauyRc1UEVsiURuV/iImNL0EdI4ji4OttgOspa5yL4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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