SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8fad2f9dcf426f3ff454a52ff72311dbc0992023de1b6ee14320c7e9c9d3be57' 
  AND token = 'xvxhSiCOo8DAovBaKz0tICX01x2UCVjp9LZPgZjoM8Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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