SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '44dcbb913e02fbd4da73ff82488896ccfbeb3613634f3c321115c46645eb6b99' 
  AND token = 'fXzx4i5Qd8j+lKNE5+GalAwHzmDK1tqXueIYWDK6XqY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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