SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e77d49dba03c661faa8a4b78e22f92bdf590ab4dd0f1ce121d2638325a1fa572' 
  AND token = '/xgc++zJVfcv3HrdcDOwVdOqeBqVAgODGzHcQcYIrPQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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