SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab5f4a24e3364edc0f4a0f13277a238e8264e291623aa967815fb5fad112d133' 
  AND token = 'GYiiBIwVuunakbEjLaQFw9EP/MHwh4vwZE1YCdPUPl4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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