Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '475e63c60554de3650bad873255ea025f1428f78599fda409732544cb8d6f98f' 
  AND token = '4UKOIVVvTkI/jWCijFUxGwOSRNjQ/My8X1y0Dv04QLQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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