SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '32dbd55d3b56a61b9823e502f743420c7c7af80c064e1c9fddd969db07b842b9' 
  AND token = 'nLtDLyPBzKZy5L6JH2gUjZrDAqI6J9pkMyFt+rLiOgc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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