SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '02209d6c271206947c42fee720583c661608e57a96b6c6643f14368484c1571d' 
  AND token = 'MLHWHKq/3bdOyFZyVRCAhuNUCGJwe0ZcexQoH1WsuTA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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