SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '004acbf578e45ea5587fc4d238628eaaab9798df56a747e997600e450d4b9ff5' 
  AND token = 'oLqqlAc/1UBjtxgeLfOhUk6hHjF/SVeqoOHvlvgg+E8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00068

JSON explain

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