SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80c2e6423010fd15b921f18b587487259f120437377811c09cfbc5bb6941ca4c' 
  AND token = 'M+SvKZ+d+jpGwEzOYUVtAgL+maanQDWxqBbJaXgQxrE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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