SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7edbb06625b315cbd4d20b4154c2e1d6fd139ad5fadf41c015c215320575cf60' 
  AND token = 'm1fuwiF+wxdhlp4W/eMvoZJQwANyxSkiVwS8LUHZiug=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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