SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0d305e272b399e3e7932d02863e177ab2be0bc48bf3955a9239120f0446fe2d4' 
  AND token = 'hj+LQ4jCfnQh2ZiYZ6/u7hXJavrwLcjhFhiCVJHcIs4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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