SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bc7f2c3f4806e6f1680fbc611808e49d2e572ba6010ede26ae3bfdb2dab39a9b' 
  AND token = 'shYKbvqWP2m7gu0ui+C8YlgDcJDkO3DVq/KYi7Ungoo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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