SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '898410dea85107b7fb609997fdf360fdad84ba150829c291a7b32348618d71c8' 
  AND token = 'fOPBKOOmmXnkR8+2WMbtzyziCpECAHVyUzXeuXkhn58=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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