SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41ed282603312890f710ebc7ddcd601ef5b90ab4938ac6fd275e4040784e1322' 
  AND token = 'suLQ8fVmmK0HPPy/IrGJBhwzAbsCbPM2aOjWZx1ZyZs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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