SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '996fe8cb1e98b13d0650230d71e65e9a90c4820afe9dafee91eda0687abcd850' 
  AND token = 'QASHI2m2Q+c+of19MZfHjX6JgMEHBi+WSEJ0gv4HdXk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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