SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ccb9f5fd031afdcb7e1689a66f1578a64b89cae04b60c8ac3caf8a2e05796509' 
  AND token = 'RjX5Gzr4oZMS6W/ybTUcE2Iobpx1qS8H/ugxPYOA3Cs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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