SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '22fa8b93800b64930a9afd9157be6315cbd121c86f3108810232d7504de3cba1' 
  AND token = '2TQ6zrTrWdZBW6/BpcRsuuFJgLHv4DJr8kc6Ozf83+E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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