SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b5f043d5d291fc872be92b9cdda1b3ed73b2cabd673acb3c67016c9d0d5a1508' 
  AND token = 'g9f6NEsK2N/bkjJB3w60/UHPy0fAGknRLv1uYOD/Jcs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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