SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4a8e263259e767b63965e82a7cd173a5f04f4163e5d95ca9e8031c755730096e' 
  AND token = '8bfh8GAa3eLTFMrfAQjheofxA+OlYWpLZkGASPxuhcs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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