SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bcb1b06ab48c46ae74b525839526c4ae8722de2f0187981bbf53de1c82531c53' 
  AND token = 'q02ay0wOVR1ZoxJN+CNqFS3Gz+sQv+dq4tN+hiHijSk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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