SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '52c48a00448c3210054bbb8503263e9897c97d7a9fc508867a2c376f325dce8f' 
  AND token = 'ATkUwEYs+QQB4YE50rHVtmaIyJMnGi0BXOhV8YhSZIA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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