SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '67513f04f99bdaec9d30a539e1bb257da74668715bf4d3625ba854b2633eaf36' 
  AND token = 'bbmPhlkKdPvgjjUvi3PvTAakMFKoZYo6Khrti07X5ng=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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