SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9aa08fbc326340174181d7ecce1793d0d360a8a2d283358ae2e05fb70279c695' 
  AND token = 'qWeNWpIlwmbcrivomZdFO6DE/vOWa40R0icJklt29F4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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