SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b80362566ba452716400c789f413b47964e4be345f0c9743bb61ca14bd4e520' 
  AND token = 'kuRsxhfm6hBYqmGF9DtKG4uXM8nNVLZo5sUlc7T6byc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00011

JSON explain

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