SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a2f9d96312b5cc9851b3b48e91a5946a0f4b3ead3e0f751c57b982ae6b6c48ee' 
  AND token = '7hfoONwFB2/D8gsFtMDg9c34J1ozBYZqv4oRiIGh5Oo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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