SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed97ecddc2031f9a52139c92ee3984aebe2943bd9329ce5156bc33ef779c0c42' 
  AND token = 'FXONq+mKVxcDGFrHjLh2IDFW3CUvWiamgSqZxc00CKc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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