SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fcacace1044884215173bd4cd465d9f85ef5931956bd29f5623716a7a6f458a8' 
  AND token = 'iBIMrZ7f/ZDKWOINFHHQ23qUIXgfpsvcmIytB0hlUbI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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