Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '270eb51fce3bedcbe0947687d3dd14e065d544e39b137c310cbfd74c120b7e81' 
  AND token = 'SdLdswF2eubPR+E813aeeCBGlpZghEYCzExPnKuWhWI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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