Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6abe5b18ceaed1f08b42b1f4fe6f7affe8735d2dfdfa708a1ebde3bbbd0722b6' 
  AND token = 'B953Z0v3j6dHy5RVxdP3iXwrtSnTQ1nnethJvtV4idc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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