SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '08c9930426411d754ba20fe8db79253a5f6d8c92def9cd216eafe02a9b703aaf' 
  AND token = '/fkt+1VS99CC8NHLmqH+OCoi39KKHxq9QeV0xoF7Csk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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