SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5802a193ce78c35ae50c4871c97850c4ecf94c0697c681f58458c6d824fd5f73' 
  AND token = 'pBHC2trqkJoXSJXdSm2+Bc0jlMtyviU0aeYzOw67cvo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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