SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e7f15de462ccad692b01ae415427dec65083f0a36a3fcc42f5ad643db3443685' 
  AND token = 'MdzE39G9Z8JfH6Pq4GD5nNibLlcIeFcm49Fu1L+k8eI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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