SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ef7f160b75e662cfe40f5b7c61b48bbd97db9e4adef58f80bfb5737ad3a69ec2' 
  AND token = 'HqgcfWmIJbrcnOrR7bL/+1MghQv5zDvEYH4GZyWKJgk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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