SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e4c0c0c12329daa9f12ee1aa2fabb8fdcd71b9358002fa8751c582f8b57430e1' 
  AND token = 'mgbuoFBQBn5bbLvdKgSmn8wItKjN5P1kdElo3GGzVKw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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