SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '97d5d4a324080c6b2971bb73d73f1bd0e67bf94cb9b0156080fc2715804149d5' 
  AND token = 'dxPpgKOgvytST/KNvVXz/sAdKMnv4T1AvRUVaFgp+ew=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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