SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1579d295d3671ce531238b3bf79bd9f8e3fa7e1f563b7eb4fff8071c1395393' 
  AND token = 'LVI1KAaC0EgihsLMYgTU2CS2hKhGzF/d2yC7wacdrBM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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