SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '63d55f796d1acba65bb36bc828af852fcbffb694d49f19ba233604bdfc2ab6bf' 
  AND token = 'AD6rDngSxylOQCK6bUdGdXAjZUB35kVa5r/2Ospgg3Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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