SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e8269482b63285d1ae2bf7400955a32cce78ca0424d94ed8465374af110bbece' 
  AND token = 'GrxoYSpQkRZ1saSZpUwKrJxLD4sxfiQeaamwJyHKGGQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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