SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd2561719ebf29d9b5dcc6cc1301b9ba3d1df9ead648786d8b9922f030f0fa6a8' 
  AND token = 'p7U4uUQbu/UzHxQVH/Y+xkoSKtEJlVfugLOJoqnc8+o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}