SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '563217caea3a64618a9c9ccfdcabbd24a168439a307dd72f08f8f1247d262889' 
  AND token = 'Y/dhiNfvml0r1S71LVGJsubqFyokXwPAKppTX3TdGsE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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