SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0065136d1251f789ecdd05848af2640167c1965cbb864f8c9f4f25047c6debc9' 
  AND token = 't/zqza2XtSaImVOpppqyCiQdrl/Num4bfiPVSEqK1P8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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