SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b460c23cc21dd6b5e99ec7f002f87c35820a41f85d6aff39b7b5a247ad325d5f' 
  AND token = '1g8H2j9743W3oBcBvtNtHhW6glbQhriAWbWLy9lB/MQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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