SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3d0c3c7b8b279c89e600fd0fe36bc3fbfe83c2591572c653bb2ac7badd3f47f5' 
  AND token = 'B5aQiBdkDCaDuDf4uXL61knE1CEI+2rZs7OStihGwzU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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