SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf0162427a8e017b5d85ae2ec8a2339649be084e1207be39d3df260e04a369b3' 
  AND token = 'DpKWiGZFTvUwWCkMkoSrYqkLOMXPzf4bpCQb5L2iYJU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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