SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fcd426e1566aedfd2e473252180fbbba82a3ea746ee744db7545e238fdb15bff' 
  AND token = 'EXd4Y1JBoqV121XOWPiRU99rJdbO9qcbpN0QKw/ei3Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00060

JSON explain

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