SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30ae06c2cfdaef1864ec19af768f2d89ef8065f6cafd8a3b828eaa617364d467' 
  AND token = 'DsM8hL5ZYjWvHbp/sDcYME6BaCQ0iGf1yqgH4zgx7B0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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