SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6388d2649a5b7aed1ec139ae8ecb6ecb55eac595b1a81c18830379515b9a87a7' 
  AND token = 'HpPripfLKG//IcpEOqyRabtA2hvLXirihTxlL0FnqwI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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