SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '394f0894d8e6d5c81fd04c8858c9e1a74e77cf9b8107ab06c6c620756e27e344' 
  AND token = 'en7W4WC+wo5+ubywz1FzC1YtLxUljDtcsjX3IcjsaDE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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