SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd93f9e16527afdcdab96590d72bfa2b1fa81161714ff3587e7e5751df0e375a6' 
  AND token = '8NRHl2eMsOy5BzskfLSW1GEmmalsuJjbiOeTj7xFzLs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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