SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c70a7d679eff53e02c8b63df630712a60ce47fb93a54981a3d6e137efb24a95d' 
  AND token = 'hbpFHYozC1xx9wgOFPF7hn2uwY9ldj0Kg4oz6ELFDBA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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