SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a2b8f104016fd9db466a0203cc027c7bf8f7792c49462477a02a72939d9e458' 
  AND token = 'Fb5PWq31DwlzlfTATxoBojGGSUhZl2QZBV51BmDx76M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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