SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4bfc1a53d4e5feb10ffa4b172acf999e378bed9c3c504c998a13c1301fb03948' 
  AND token = 'VvLhwBHCnHXFagQOK2OefHkQ0B/h0n34Zs3lD9Hutwc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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