SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64ab4193d5fc9b66cd0aea22836df9ef056b72c8e10935a7515614d877f80316' 
  AND token = 'imLIvBE7QWg86FCOnuv7/CM+/296UDAwhDR0b1ocqwU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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