SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ae18448e71f40915d81bf944cebd3266ed9700958bc9b54e81e46ad36909dd4' 
  AND token = 'vW4ZIBPWPnCkolKVYCip3KeNFoGnQZfPIuWXfU1Bbhc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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