SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d9f5dfb162de2440a4ab2416918105f691a04044e1a5f81540349339071fac0' 
  AND token = 'Pva9PUW4NK41uucMvuVaZZpwpit/oTZycHIPIJcef/I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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