SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ca7801e6ccae44fef6fd270f88712f9ad3e48e26bd4a54a365897a2f43e0d70c' 
  AND token = 'VzmwZ6XTYXEV0YAKKvbFgKudCgD/lySP52YPoBOzb6A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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