SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7dc781c9d3c39c7a4c0f43979f30afa78143ad0d3674d055b07f7e924afe9a18' 
  AND token = 'rpFss5ZkeuhtgpDnxG63/DvX3HEIq1ZwjqssTCbNG6U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}