SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fe9fecd004abe54895b4c92194fc9b4688a55472ff5022498478ace575eed9c0' 
  AND token = 'QOPhxFwmZAhXJdqY+vyekGqO6b0KGFxAXDMw8RgW/cE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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