SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '722717511b2ff1ebd863b5fc9ee7d62062c816f33632c55bd17bced3c7de83bd' 
  AND token = 'oa6QvOIz0ZAgSgp5CveN6zbK8XAKRNuT1nzAIVzpqn0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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