SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '86fcdfe1109fc4eab40bde4b7f0dea743ecd1fcf791d659f111d574e2f0789ab' 
  AND token = 'DqVep3sOGEpQBfp6Ml3Jh4fCKmoxWSMNi27me1bJoZA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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