SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd8e8b5613f9f07e5ce0b813a69c513aa7b7c36bc7c667d9c0a48d8d2b349a43c' 
  AND token = 'MouFGNRr1EjzQsZmupg61DJKHNngvI9Av/t9rkkkJJk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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