SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '14bcd7879213ba9688125fcb1c42161594014465ce967dc58315c6af9f8b531c' 
  AND token = 'yKGresP6xTeqAhQ7VvcXdEzAg8fn7Zo1PWhHvVBd6zQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}