SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8d72d667aead8e91a026e4a095891b3d816e3f60e64ae4effe61e94321ec5be6' 
  AND token = 'OaM2l6QVCSdG2Ud0vspiHrGHWYGtuwjI7/hQKjocl0E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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