Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9a7fa3fb43b4dd07f8dfaaf7961e4aa0081c51689b1e11a17d78b18ced9b3f8a' 
  AND token = 'Ydw0ugR7InLu4u+83uP4n8fD8EwFC0x284kxBCE50Xo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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