SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed9a091ac2739ce738256697b51f0fbb42763e6ad0b3ec6754d2f9f3f098162b' 
  AND token = 'jA1OdNDOOsSkads2V4osjILusAvJlyNeuz4T4ZXEH4U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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