SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1c69c4f7ee300abaf6b94c950e2e525bc9fa5320f1d4436dc7d62dd3d1fd6577' 
  AND token = '7mKh2M4Yadn9H+SvkJaEVlMtEeuU0nmgC9q1Iouyurc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00089

JSON explain

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