SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'efae6c110f06965333632081bf8da4a54f5e763443762cd9b65b8961f14254d6' 
  AND token = 'Is0wZVidckoivm1YBVVYohdRUzInXkgLsWH+X4SGd/0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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