SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd700ada5ab94e9be9b21fa58ef01e0667a59dfb7489db418d75316ed367fbdf3' 
  AND token = 'sLEwhBc6YupTHeAzvVSP92xJ3IihRxM8ztwitMH86j8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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