SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e98d23bc0c25db547d1b492c8b8255c1593552fe81c26e47e78c51ff29e3b7b2' 
  AND token = '8tSdwyC4Ewy0v6u3Ho8FbicKyqM+CQc/sT0UypdudQ8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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