SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ad27dbe8f9be540dd6809570d5d0749d7f084a73695fa296f14a894ebd14a35' 
  AND token = 'Ley7jS63a35z+TNpZyEFDhnZiV92C59Rguwldvf7Sss=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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