SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '53b4b3497c6f6452a5ca0657f595866ae0ad85da29ff86b47b35d40ffe4e5006' 
  AND token = 'BzVY+C9wlBgvoAVnx2mhm1JFVYWS3rnEVb0PnySdwAY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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