SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '97c5b0e0c638ffeb17257b8a6304548be946d83ebcd9eb0d295bbd6de7eb76db' 
  AND token = '5O5on1/6FF1VgT0+qIdr+8i7cS1kYHDDKmYmBBuTDKE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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