SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '77e36322cae0dff741d2d61388ab9df85e7a01899a9216ab3499fbf03c1f8266' 
  AND token = 'YLa+sXIjszhn9LJY1lmG1OpzPAqyF8m13z1oN5mw1yY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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