SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '96fa384e14ff24512971a2e02065599d030e988b1b38b52376ba8cfddedee9b8' 
  AND token = 'tpQIuVGzEUF/Pa2gi1/fvGh3c2dvCdlAuUNwVV+IaVw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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