SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8c6e811315f85624c0c74c67143fa5ffaa6dc47eede76c51ea1848e0fd96dad8' 
  AND token = 'yfBJRxJhcCIkV3tKqkNILk6ny+bBzoupZZHM75aGbFI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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