SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e3722b2df466e9b436a5140bd31cc9622a748fdddc9bfc7139eaceed09ab4bbf' 
  AND token = '/weh9/JljLPaSsoLa3rLIka7FcECPuIXkqBi7iH04Cw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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