SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd4f0a49928e699dfeac0fa1ad7b128b02367cca1f831364b43c9727c8cdb2c62' 
  AND token = 'uU9BtAab3oDa3Z5gkeiq/+QFH7fWaO37aMVrSIZWj6A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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