SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '602921cacd3085f20357bb183fb460dc14a01044a4c82a8cfbbc1d9c57a38f01' 
  AND token = 'DZ/DWvC5EwfbWhJ7NfGIj0Og2VBxzKfTjMD+/yz9ugw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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