SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '34426332f728468ee7282d3d356c23f2a574a1bbab7789bcaf1bdb47cd99716c' 
  AND token = '2FvwsziD2EGXV0fPHBUelO1jNkj/XQjxbB3lps3OeVY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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