SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '046803fe64c51d5b6df5a197438b1b2309fc457ba5e368ba0cfb8a8767db97b5' 
  AND token = 'ke6shFjdh370dyIqxVFeYUTWE9cL/yWDBlRSG/AcGBs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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