SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e7443d3873d476f0b22a41c7464f142454f99f0da83c201cec38b37f0e81bf9f' 
  AND token = 'ljgd7C4gzd2wKR90kJaYKLt5syjGUnSUDQPbJ5ECxc0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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