SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '221cb2c7596ad7813727e094a905cac062b9e39c0262d70104d689a162d450dc' 
  AND token = 'azEkEnOYWABoUzY2sfLt3m0E2+4ueDEtQZnikp4KM8I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00073

JSON explain

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